Search

Objective: This study aims to assess the accuracy and stability of smartwatches in predicting acute mountain sickness (AMS)., Methods: In locations exceeding an altitude of 2500 m, a cohort of 42 subjects had their Lake Louise AMS self-assessment score, blood oxygen saturation (SpO 2 ), heart rate, and perfusion index measured using smartwatches, with the data seamlessly conveyed to the Huawei Cloud., Results: A significant decrease in SpO 2 was observed in individuals positive for AMS compared to those negative ( p  < 0.05), with the mild AMS group exhibiting significantly lower SpO 2 levels than the non-AMS group ( p  < 0.05). Furthermore, SpO 2 emerged as a significant, independent predictor of AMS [ β =-0.086, p  < 0.01, OR (95% CI) = 0.92 (0.87-0.97)], indicating that each unit increase in SpO 2 decreases the probability of AMS occurrence by 8.6%., Conclusion: The Huawei smartwatches have demonstrated efficacy in diagnosing and foretelling AMS at elevations exceeding 4000 m, showcasing significant reliability and high precision in SpO 2 measurement ., Competing Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Introduction: Perfusion index (PI) is used as assessment of epidural anaesthesia efficacy in human medicine, but its usefulness in dogs is unknown. The aim of this study was to evaluate the usefulness of PI in determining epidural anaesthesia effectiveness., Material and Methods: This is prospective cross-over experimental study. Five healthy adult beagle dogs were anaesthetised and an epidural catheter was inserted in the lumbosacral area and adjusted so that the end of the catheter was placed at the fourth lumbar vertebra. Single-port catheters were used in the control group and multiple-port catheters were used in the treatment group. A PI probe was placed on a hind leg, and the catheter placement was confirmed via computed tomography. The treatment group received a bolus dose of lidocaine, and the control group received saline, via epidural catheter. The PI value was recorded every 5 min until 30 min after lidocaine injection., Results: The PIs of the hind limbs were not significantly different over time, nor were they between the control and lidocaine-injected groups at any point in time., Conclusion: The PI is not useful in determining the efficacy of epidural anaesthesia in dogs under general anaesthesia. In the future, finding a reliable method to evaluate the success of regional anaesthesia, even in patients under general anaesthesia, will be necessary., Competing Interests: Conflict of Interests Statement: The authors declare that there is no conflict of interests regarding the publication of this article., (© 2024 Harumichi Itoh et al., published by Sciendo.)

Background: We investigated the performance of the Perfusion Index (PI) derived from pulse oximetry waveform as a tool for assessment of anesthetic depth in comparison with A-line Autoregression Index (AAI) derived from analysis of Middle-Latency Auditory Evoked Potentials (MLAEP) waveform integrated by aepEXplus monitor in children receiving sevoflurane anesthesia for tonsillectomy., Methods: Forty-one patients (4...12 years old) were included in this study. The PI and AAI were recorded simultaneously every minute during different stages of anesthesia delivery. The statistical tests included descriptive analysis, significance tests, correlation tests, and Receiver Operating Characteristic (ROC) curve. The AAI served as a reference., Results: The PI significantly decreased during light anesthesia and recovery, and significantly increased during deeper planes of anesthesia, with an inverse mirror-image relationship with the AAI. A negative correlation of low to moderate degree was detected between PI and AAI during the study (p.ß>.ß0.05), that reached a statistical significance at the 5th minute during sevoflurane mask induction (r.ß=.ß...0.457, p.ß=.ß0.008). ROC analysis at an AAI < 25 extracted the best cut-off value for PI before intubation as 1.48 (AUC.ß=.ß0.698 [0.537...0.859], 94.4% sensitivity, 44.5% specificity) and at 10-minute intraoperatively as 2.4 (AUC.ß=.ß0.537 [0.354...0.721], 91.7% sensitivity, 31% specificity). During recovery, at an AAI.ß....ß50, the best cutoff was 1.82 (AUC.ß=.ß0.661 [0.46...0.863], 100% sensitivity and 50% specificity) 2 minutes before spontaneous eye opening., Conclusions: Compared with the AAI, the PI can track changes in depth of anesthesia in pediatric patients undergoing tonsillectomy under sevoflurane anesthesia., Trial Registration: Clinical Trials. Gov. Identifier: NCT03412214., (Copyright © 2021 Sociedade Brasileira de Anestesiologia. Published by Elsevier España S.L.U. All rights reserved.)

Post-induction hypotension (PIH) is a common and potentially serious complication of general anesthesia. This meta-analysis (Prospero registration number: CRD42024566321) aimed to evaluate the predictive efficacy of the perfusion index (PI) for PIH in patients undergoing general anesthesia. A comprehensive literature search was performed using multiple electronic databases (Google Scholar, EMBASE, Cochrane Library, and MEDLINE). Studies involving adult patients undergoing general anesthesia, with the PI measured before anesthesia induction and reporting PIH incidence, were included. The primary outcome was the diagnostic accuracy of the PI in predicting the probability of PIH. The secondary outcome was the pooled PIH incidence. Eight studies with 678 patients were included. The pooled incidence of PIH was 44.8% (95% confidence interval [CI]: 29.9%-60.8%). The combined sensitivity and specificity of the PI for predicting PIH were 0.84 (95% CI: 0.65-0.94) and 0.82 (95% CI: 0.70-0.90), respectively. The summary receiver operating characteristic (sROC) analysis revealed an area under curve of 0.89 (95% CI: 0.86-0.92). The Deek's funnel plot asymmetry test indicated no significant publication bias. The PI demonstrates high predictive efficacy for PIH in patients undergoing general anesthesia, indicating that it can be a valuable tool for identifying those at risk of PIH.

Study Objective: Evidence for red blood cell (RBC) transfusion thresholds in the intraoperative setting is limited, and current perioperative recommendations may not correspond with individual intraoperative physiological demands. Hemodynamics relevant for the decision to transfuse may include peripheral perfusion index (PPI). The objective of this prospective study was to assess the associations of PPI and hemoglobin levels with the risk of postoperative morbidity and mortality., Design: Multicenter cohort study., Setting: Bispebjerg and Hvidovre University Hospitals, Copenhagen, Denmark., Patients: We included 741 patients who underwent acute high risk abdominal surgery or hip fracture surgery., Interventions: No interventions were carried out., Measurements: Principal values collected included measurements of peripheral perfusion index and hemoglobin values., Methods: The study was conducted using prospectively obtained data on adults who underwent emergency high-risk surgery. Subjects were categorized into high vs. low subgroups stratified by pre-defined PPI levels (PPI: > 1.5 vs. < 1.5) and Hb levels (Hb: > 9.7 g/dL vs. < 9.7 g/dL). The study assessed mortality and severe postoperative complications within 90 days., Main Results: We included 741 patients. 90-day mortality was 21% (n = 154), frequency of severe postoperative complications was 31% (n = 231). Patients with both low PPI and low Hb had the highest adjusted odds ratio for both 90-day severe postoperative complications (2.95, [1.62-5.45]) and 90-day mortality (3.13, [1.45-7.11]). A comparison of patients with low PPI and low Hb to those with high PPI and low Hb detected significantly higher 90-day mortality risk in the low PPI and low Hb group (OR 8.6, [1.57-162.10])., Conclusion: High PPI in acute surgical patients who also presents with anemia was associated with a significantly better outcome when compared with patients with both low PPI and anemia. PPI should therefore be further investigated as a potential parameter to guide intraoperative RBC transfusion therapy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. CSM has co-founded a start-up company, WARD24/7 ApS, with the aim of pursuing the regulatory and commercial activities of the WARD-project (Wireless Assessment of Respiratory and circulatory Distress, a project developing a clinical support system for continuous wireless monitoring of vital signs). WARD24/7 ApS has obtained license agreement for any WARD-project software and patents. One patent has been filed: “Wireless Assessment of Respiratory and circulatory Distress (WARD), EP 21184712.4 and EP 21205557.8”., (Copyright © 2023. Published by Elsevier Inc.)

Purpose: One of the regional anesthetic procedures, caudal epidural block, is important for lower extremities surgeries in the pediatric patient population. The perfusion index (PI) value, which reflects vasomotor tone, can be used to indicate block success. The aim was to compare the role of perfusion index, heart rate, and mean arterial pressure in detecting the success of caudal epidural block and to investigate whether perfusion index was an earlier indicator in determining the success of the block in pediatric surgery cases., Design: A randomized controlled trial., Methods: The study included 58 patients, American Society of Anesthesiologists'classification 1, between the ages 1 and 6 years. In the left lateral decubitus posture, caudal epidural block was performed using a 23 or 25-gauge caudal needle and a dosage of 0.25% bupivacaine (1 mL/kg). At the 0, 1, 5, 7, 10, 15, and 20th minutes, peripheral oxygen saturation, heart rate, mean arterial pressure, and PI values were obtained using a probe attached to the first toe of the left foot. A successful caudal epidural block indication was defined as an increase of at least 100% in the PI value over the baseline value and a 15% decrease in mean arterial pressure and heart rate FINDINGS: PI represents the ratio of the photoplethysmography signal to pulsatile over nonpulsatile light absorbance. An increase in the PI value indicates that the block is effective. In the 20-minute follow-up period after caudal epidural block, there was at least a 100% increase in PI value in all of the patients at the seventh minute. An expected 15% reduction in mean arterial pressure was observed in 14.5% of the patients and an expected 15% reduction in heart rate was observed in 45.6% of the patients., Conclusions: The results obtained from our study show that the increase in PI values is associated with caudal epidural block success. The PI value is more rapid, sensitive and objective than those produced by other parameters. Benefits include an earlier change in anesthesia management due to block failure and faster initiation to surgery, which reduces exposure to anesthetic chemicals., Competing Interests: Declaration of Competing Interest There were no potential conflicts of interest relevant to this article., (Copyright © 2024 The American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.)

Background: This study aimed to evaluate the effect of ICC (cord clamping within the first 15 s), DCC (delayed cord clamping at 60 s), and cut-UCM (cut-umbilical cord milking, cord clamping within the first 15 s) groups on oxygen saturation (SpO2), heart rate (HR), and perfusion index (PI) up to 10 min after birth in newborn infants., Methods: We conducted this randomized clinical trial in the delivery unit of a University Hospital with 189 infants born between 35 and 42 weeks of gestation. Participants were randomly assigned to one of three groups: ICC, DCC, and cut-UCM. The primary outcomes measured were SpO2, HR, and PI at the 1st, 3rd, 5th, and 10th minutes after birth. We utilized ANOVA and Bayesian calculations in this study., Results: There was no difference between the ICC, DCC, and cut-UCM groups in SpO2, HR, and PI values at the 1st, 3rd, 5th, and 10th minutes of life, which did not significantly alter between the three groups in one-way ANOVA. Bayesian repeated-measure ANOVA calculations showed that SpO2 and heart rate results at the 1st, 3rd, 5th, and 10th minutes did not differ between ICC, DCC, and cut-UCM techniques with strong evidence. At the 3rd minute, PI was slightly higher in the DCC and cut-UCM groups compared to the ICC group, with anecdotal evidence. We found no difference between DCC and cut-UCM regarding the 3rd-minute PI, with moderate evidence., Conclusion: Umbilical clamping procedures (ICC, DCC, and cut-UCM) did not affect SpO2 and HR in the first ten minutes of life, but 3rd-minute PI values were slightly higher in DCC and cut-UCM compared with ICC among late preterm and term neonates., Competing Interests: Declaration of competing interest Authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: The peripheral perfusion index (PI) reflects microcirculatory blood flow perfusion and indicates the severity and prognosis of sepsis. Method: The cohort comprised 208 patients admitted to the intensive care unit (ICU) with infection, among which 117 had sepsis. Demographics, medication history, ICU variables, and laboratory indexes were collected. Primary endpoints were in-hospital mortality and 28-day mortality. Secondary endpoints included organ function variables (coagulation function, liver function, renal function, and myocardial injury), lactate concentration, mechanical ventilation time, and length of ICU stay. Univariate and multivariate analyses were conducted to assess the associations between the PI and clinical outcomes. Sensitivity analyses were performed to explore the associations between the PI and organ functions in the sepsis and nonsepsis groups. Result: The PI was negatively associated with in-hospital mortality (odds ratio [OR] 0.29, 95% confidence interval [CI] 0.15 to 0.55), but was not associated with 28-day mortality. The PI was negatively associated with the coagulation markers prothrombin time (PT) (β -0.36, 95% CI -0.59 to 0.13) and activated partial thromboplastin time (APTT) (β -1.08, 95% CI -1.86 to 0.31), and the myocardial injury marker cardiac troponin I (cTnI) (β -2085.48, 95% CI -3892.35 to 278.61) in univariate analysis, and with the PT (β -0.36, 95% CI -0.60 to 0.13) in multivariate analysis. The PI was negatively associated with the lactate concentration (β -0.57, 95% CI -0.95 to 0.19), mechanical ventilation time (β -23.11, 95% CI -36.54 to 9.69), and length of ICU stay (β -1.28, 95% CI -2.01 to 0.55). Sensitivity analyses showed that the PI was significantly associated with coagulation markers (PT and APTT) and a myocardial injury marker (cTnI) in patients with sepsis, suggesting that the associations between the PI and organ function were stronger in the sepsis group than the nonsepsis group. Conclusion: The PI provides new insights for assessing the disease severity, short-term prognosis, and organ function damage in ICU patients with sepsis, laying a theoretical foundation for future research., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: We aimed to evaluate the ability of the peripheral perfusion index (PPI) to predict reintubation of critically ill surgical patients., Methods: This prospective observational study included mechanically ventilated adults who were extubated after a successful spontaneous breathing trial (SBT). The patients were followed up for the next 48 h for the need for reintubation. The heart rate, systolic blood pressure, respiratory rate, peripheral arterial oxygen saturation (SpO 2 ), and PPI were measured before-, at the end of SBT, 1 and 2 h postextubation. The primary outcome was the ability of PPI 1 h postextubation to predict reintubation using area under the receiver operating characteristic curve (AUC) analysis. Univariate and multivariate analyses were performed to identify predictors for reintubation., Results: Data from 62 patients were analysed. Reintubation occurred in 12/62 (19%) of the patients. Reintubated patients had higher heart rate and respiratory rate; and lower SpO 2 and PPI than successfully weaned patients. The AUC (95%confidence interval) for the ability of PPI at 1 h postextubation to predict reintubation was 0.82 (0.71-0.91) with a negative predictive value of 97%, at a cutoff value of ≤ 2.5. Low PPI and high respiratory rate were the independent predictors for reintubation., Conclusion: PPI early after extubation is a useful tool for prediction of reintubation. Low PPI is an independent risk factor for reintubation. A PPI > 2.5, one hour after extubation can confirm successful extubation., (© 2024. The Author(s).)

Sepsis is associated with hypoperfusion and organ failure. The aims of the study were: 1) to assess the effect of pimobendan on macrocirculation and perfusion and 2) to describe a multimodal approach to the assessment of perfusion in sepsis and compare the evolution of the perfusion parameters. Eighteen anaesthetized female piglets were equipped for macrocirculation monitoring. Sepsis was induced by an infusion of Pseudomonas aeruginosa. After the occurrence of hypotension, animals were resuscitated. Nine pigs received pimobendan at the start of resuscitation maneuvers, the others received saline. Tissue perfusion was assessed using temperature gradients measured with infrared thermography (TG = core temperature - tarsus temperature), urethral perfusion index (uPI) derived from photoplethysmography and sublingual microcirculation (Sidestream dark field imaging device): De Backer score (DBs), proportion of perfused vessels (PPV), microvascular flow index (MFI) and heterogeneity index (HI). Arterial lactate and ScvO 2 were also measured. Pimobendan did not improve tissue perfusion nor macrocirculation. It did not allow a reduction in the amount of noradrenaline and fluids administered. Sepsis was associated with tissue perfusion disorders: there were a significant decrease in uPI, PPV and ScvO 2 and a significant rise in TG. TG could significantly predict an increase in lactate. Resuscitation was associated with a significant increase in uPI, DBs, MFI, lactate and ScvO 2 . There were fair correlations between the different perfusion parameters. In this model, pimobendan did not show any benefit. The multimodal approach allowed the detection of tissue perfusion alteration but only temperature gradients predicted the increase in lactatemia., Competing Interests: Declaration of competing interest Boehringer Ingelheim Animal Health France (Lyon, France) provided the drugs necessary for the study. The authors declare that they have no other competing financial interests or personal relationships that could have influenced the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Peripheral perfusion index (PPI) is useful in a variety of neonatal settings. Currently, available reference values are from small numbers and highly variable., Methods: We sought to generate reference values of PPI by analysing previously collected data from newborns who underwent mandated universal pulse oximetry and PPI screening from 2018 to 2021 using uniform protocol and equipment. Q-Q plots and boxplots were used to visualise distributions. Kernel density estimation for heaped and rounded data was used to estimate percentiles of the distributions., Results: Data from 388 205 newborns who underwent universal pulse oximetry screening in the first week of life were used for this analysis. Pre and postductal values showed a non-normal distribution and skewed to the left, the former had a thicker tail with more extreme values. Minor, but statistically significant differences were seen in the PPI values from day 1 to 7. Median preductal PPI (2.77, IQR:1.83-3.93) was significantly higher than postductal (2.38 IQR: 1.41-3.55) (p<0.01). PPI values increased with weight and boys had higher PPI. Kernel estimates of the percentiles in the overall sample and subgroups for gender and weight have been provided for preductal and post-ductal values., Conclusion: This study, based on the largest available dataset, provides reference values for PPI in newborns. A significant influence of gender and birth weight on PPI values in newborns has been identified. Future research on understanding the influence of age, sex, birth weight, gestational age, ambient temperature and genetic factors on PPI is recommended., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Intraoperative fluid therapy maintains normovolemia, normal tissue perfusion, normal metabolic function, normal electrolytes, and acid-base status. Plethysmographic variability index has been shown to predict fluid responsiveness but its role in guiding intraoperative fluid therapy is still elusive., Aims: The aim of the present study was to compare intraoperative goal-directed fluid therapy based on plethysmographic variability index with liberal fluid therapy in term neonates undergoing abdominal surgeries., Methods: A prospective randomized controlled study was conducted in a tertiary care centre, over a period of 18 months. A total of 30 neonates completed the study out of 132 neonates screened. Neonates with tracheoesophageal fistula, congenital diaphragmatic hernia, congenital heart disease, respiratory disorders, creatinine clearance <90 mL/min and who were hemodynamically unstable were excluded. Neonates were randomized to goal-directed fluid therapy group where the plethysmographic variability index was targeted at <18 or liberal fluid therapy group. Primary outcome was comparison of total amount of fluid infused intraoperatively in both the groups. Secondary outcomes included intraoperative and postoperative arterial blood gas parameters, biochemical parameters, use of vasopressors, number of fluid boluses, complications and duration of hospital stay., Results: There was no significant difference in total intraoperative fluid infused [90 (84-117.5 mL) in goal-directed fluid therapy and 105 (85.5-144.5 mL) in liberal fluid therapy group (p = .406)], median difference (95% CI) -15 (-49.1 to 19.1). There was a decrease in serum lactate levels in both groups from preoperative to postoperative 24 h. The amount of fluid infused before dopamine administration was significantly higher in liberal fluid therapy group (58 [50.25-65 mL]) compared to goal-directed fluid therapy group (36 [22-44 mL], p = .008), median difference (95% CI) -22 (-46 to 2). In postoperative period, the total amount of fluid intake over 24 h was comparable in two groups (222 [204-253 mL] in goal-directed fluid therapy group and 224 [179.5-289.5 mL] in liberal fluid therapy group, p = .917) median difference (95% CI) cutoff -2 (-65.3 to 61.2)., Conclusion: Intraoperative plethysmographic variability index-guided goal-directed fluid therapy was comparable to liberal fluid therapy in terms of total volume of fluid infused in neonates during perioperative period. More randomized controlled trials with higher sample size are required., Trial Registration: Central Trial Registry of India (CTRI/2020/02/023561)., (© 2024 John Wiley & Sons Ltd.)

Objectives: The multifactorial dynamic perfusion index was recently introduced as a predictor of cardiac surgery-associated acute kidney injury. The multifactorial dynamic perfusion index was developed based on retrospective data retrieved from the patient files. The present study aims to prospectively validate this index in an external series of patients, through an on-line measure of its various components., Methods: Inclusion criteria were adult patients undergoing cardiac surgery with cardiopulmonary bypass. Data collection included preoperative factors and cardiopulmonary bypass-related factors. These were collected on-line using a dedicated monitor. Factors composing the multifactorial dynamic perfusion index are the nadir haematocrit, the nadir oxygen delivery, the time of exposure to a low oxygen delivery, the nadir mean arterial pressure, cardiopulmonary bypass duration, the use of red blood cell transfusions and the peak arterial lactates., Results: Two hundred adult patients were investigated. The multifactorial dynamic perfusion index had a good (c-statistics 0.81) discrimination for cardiac surgery-associated acute kidney injury (any stage) and an excellent (c-statistics 0.93) discrimination for severe patterns (stage 2-3). Calibration was modest for cardiac surgery-associated acute kidney injury (any stage) and good for stage 2-3. The use of vasoconstrictors was an additional factor associated with cardiac surgery-associated acute kidney injury., Conclusions: The multifactorial dynamic perfusion index is validated for discrimination of cardiac surgery-associated acute kidney injury risk. It incorporates modifiable risk factors, and may help in reducing the occurrence of cardiac surgery-associated acute kidney injury., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Background: Several noninvasive solutions are available for the assessment of patients at risk of deterioration. Capnography, in the form of end-tidal exhaled CO2 (ETCO2) and perfusion index (PI), could provide relevant information about patient prognosis. The aim of the present project was to determine the association of ETCO2 and PI with mortality of patients admitted to the emergency department (ED)., Methods: Multicenter, prospective, cohort study of adult patients with acute disease who needed continuous monitoring in the ED. The study included two tertiary hospitals in Spain between October 2022 and June 2023. The primary outcome of the study was in-hospital mortality (all-cause). Demographics, vital signs, ETCO2 and PI were collected., Results: A total of 687 patients were included in the study. The in-hospital mortality rate was 6.8%. The median age was 79 years (IQR: 69-86), and 63.3% were males. The median ETCO2 value was 30 mmHg (26-35) in survivors and 23 mmHg (16-30) in nonsurvivors (p = 0.001). For the PI, the medians were 4.7% (2.8-8.1) for survivors and 2.5% (0.98-4-4) for nonsurvivors (p < 0.001). The model that presented the best AUC was age (odds ratio (OR): 1.02 (1.00-1.05)), the respiratory rate (OR: 1.06 (1.02-1.11)), and the PI (OR: 0.83 (0.75-0.91)), with a result of 0.840 (95% CI: 0.795-0.886); the model with the respiratory rate (OR: 1.05 (1.01-1.10)), the PI (OR: 0.84 (0.76-0.93)), and the ETCO2 (no statistically significant OR), with an AUC of 0.838 (95% CI: 0.787-0.889)., Conclusions: The present study showed that the PI and respiratory rate are independently associated with in-hospital mortality. Both the PI and ETCO2 are predictive parameters with improved prognostic performance compared with that of standard vital signs., Competing Interests: Declaration of competing interest The authors have no disclosures to make., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The erector spinae plane block (ESPB) is an interfascial plane block for managing neuropathic thoracic pain. Although the ESPB is applied widely in various clinical situations, no studies have evaluated the association between the analgesic outcomes of the ESPB and the numerical changes in the perfusion index (PI) and PI ratio., Objectives: The purpose of this study is to investigate the association between the clinical response following ESPB and other possible factors, including changes in the PI and PI ratio., Study Design: A prospective, nonrandomized, and open-label study., Setting: The pain clinic of a tertiary university hospital., Methods: This study included 92 patients with neck or arm pain who received T2 ESPB using 20 mL of 0.2% ropivacaine. To aid in the prediction of clinical outcomes, the PI was measured at the blocked side for 30 minutes as soon as the ESPB was finished. Various demographic data were also analyzed to predict the clinical outcomes., Results: Among 92 patients, 59 patients (64%) showed successful treatment outcomes (> 50% reduction in the numerical rating scale score or > 30% reduction in the neck disability index). The baseline PI of the responders was statistically higher than the nonresponders' (P < 0.05). Also, the responders' PI demonstrated statistically higher values than the nonresponders' at the time points of 4, 6, and 8 minutes after the ESPB. Multivariate logistic regression analysis revealed that a higher baseline PI (OR, 1.91; 95% CI, 1.27-2.86; P = 0.002) was an independent factor associated with a successful outcome., Limitations: Only a small number of patients with nonspinal diseases were included, except for those who had cervical radiculopathy. Therefore, it is hard to conclude that thoracic ESPB has any therapeutic benefits to patients with nonspinal diseases such as complex regional pain syndrome, adhesive capsulitis, or post-thoracotomy pain syndrome., Conclusion: A successful outcome at 4 weeks after T2 ESPB was achieved in 64% of patients with cervical radiculopathy. A higher baseline PI value was an independent factor associated with a successful response to T2 ESPB.

Background and Aims: Short-term hypotension after general anaesthesia can negatively impact surgical outcomes. This study compared the predictive potential of the pleth variability index (PVI), pulse pressure variability (PPV), and perfusion index (PI) for anaesthesia-induced hypotension. This study's primary objective was to evaluate the predictive potential of PI, PVI, and PPV for hypotension., Methods: This observational study included 140 adult patients undergoing major abdominal surgery under general anaesthesia. Mean arterial pressure, heart rate, PVI, PPV, and PI were collected at 1-min intervals up to 20 min post anaesthesia induction. Hypotension was assessed at 5-min and 15-min intervals. Receiver operating characteristic (ROC) curves were plotted to determine the diagnostic performance and best cut-off for continuous variables in predicting a dichotomous outcome. Statistical significance was kept at P < 0.05., Results: Hypotension prevalence within 5 and 15 min of anaesthesia induction was 36.4% and 45%, respectively. A PI cut-off of <3.5 had an area under the ROC curve (AUROC) of 0.647 ( P = 0.004) for a 5-min hypotension prediction. The PVI's AUROC was 0.717 ( P = 0.001) at cut-off >11.5, while PPV's AUROC was 0.742 ( P = 0.001) at cut-off >12.5. At 15 min, PVI's AUROC was 0.615 (95% confidence interval 0.521-0.708, P = 0.020), with 54.9% positive predictive value and 65.2% negative predictive value., Conclusion: PVI, PPV, and PI predicted hypotension within 5 min after general anaesthesia induction. PVI had comparatively higher accuracy, sensitivity, specificity, and positive predictive value than PI and PPV when predicting hypotension at 15 min., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Indian Journal of Anaesthesia.)

Background: The peripheral perfusion index is the ratio of pulsatile to nonpulsatile static blood flow obtained by photoplethysmography and reflects peripheral tissue perfusion. We investigated the association between intraoperative perfusion index and postoperative acute kidney injury in patients undergoing major noncardiac surgery and receiving continuous vasopressor infusions., Methods: In this exploratory post hoc analysis of a pragmatic, cluster-randomised, multicentre trial, we obtained areas and cumulative times under various thresholds of perfusion index and investigated their association with acute kidney injury in multivariable logistic regression analyses. In secondary analyses, we investigated the association of time-weighted average perfusion index with acute kidney injury. The 30-day mortality was a secondary outcome., Results: Of 2534 cases included, 8.9% developed postoperative acute kidney injury. Areas and cumulative times under a perfusion index of 3% and 2% were associated with an increased risk of acute kidney injury; the strongest association was observed for area under a perfusion index of 1% (adjusted odds ratio [aOR] 1.32, 95% confidence interval [CI] 1.00-1.74, P=0.050, per 100%∗min increase). Additionally, time-weighted average perfusion index was associated with acute kidney injury (aOR 0.82, 95% CI 0.74-0.91, P<0.001) and 30-day mortality (aOR 0.68, 95% CI 0.49-0.95, P=0.024)., Conclusions: Larger areas and longer cumulative times under thresholds of perfusion index and lower time-weighted average perfusion index were associated with postoperative acute kidney injury in patients undergoing major noncardiac surgery and receiving continuous vasopressor infusions., Clinical Trial Registration: NCT04789330., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Invasive arterial cannulation is a widely used method in intensive care units and operating rooms. However it has potential complications such as thrombosis, peripheral embolism, hematoma formation, and infection. The Masimo Root Radical-7 Pulse CO-Oximeter® (Masimo Corporation, Irvine, CA, USA) is a non-invasive hemodynamic monitoring device that measures perfusion index and pleth variability index, provides guidance to anaesthesiologists in the cases where hemodynamic fluctuations are expected. In this particular case, the perfusion index played a crucial role in the immediate diagnosis of radial artery embolism in a patient undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy procedure., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Introduction: Nerve block success is commonly assessed through a variety of techniques, including testing sensations for temperature over the relevant dermatomes and evaluating pain response (e.g., pin-prick). This meta-analysis aimed to investigate the diagnostic efficacy of Perfusion Index (PI) in identifying failed nerve blocks in patients undergoing upper extremity surgery., Evidence Acquisition: A literature search was conducted using four databases, including Medline (OVID), Google Scholar, EMBASE (OVID), and the Cochrane Database of Systematic Reviews, to identify relevant studies from the inception of the databases until June 2023. The main purpose of this study was to evaluate the diagnostic accuracy of PI values and PI ratios in identifying failed nerve blocks., Evidence Synthesis: Nine studies (published from 2006 to 2022) involving 533 participants (age ranged from 31 to 52 years) were included. The failure rate of nerve blocks ranged from 0% to 18.9%. Pooled results demonstrated promising diagnostic accuracy when using PI values as a predictor of failed nerve block (sensitivity, 77%; specificity, 88.1%; diagnostic odds ratio [DOR], 30.585). Additionally, the analysis of PI ratios as a diagnostic measure showed even higher diagnostic efficacy than using PI values alone, with a sensitivity of 82.9%, specificity of 93.1%, and DOR of 74.543., Conclusions: Our meta-analysis confirmed that the PI values and ratios are promising objective predictors of nerve block failure. The simplicity of these techniques supports their feasibility for routine clinical practice. Further studies focusing on different patient populations, such as pregnant women or the elderly, are needed to validate and expand upon our findings.

Purpose:  Evaluate the SpO 2 -SaO 2 difference between Black and White volunteer subjects having a low perfusion index (Pi) compared to those having a normal Pi., Methods:  The Pi data were abstracted from electronic files collected on 7183 paired SpO 2 -SaO 2 samples (3201 Black and 3982 White) from a recently reported desaturation study of 75 subjects (39 Black and 36 White) where SaO 2 values were sequentially decreased from 100 to 70%. The Pi values from that dataset were divided into two groups (Pi ≤ 1 or Pi > 1) for analysis. A Pi value ≤ 1 was considered "low perfusion" and a Pi value > 1 was considered "normal perfusion". Statistical calculations included values of bias (mean difference of SpO 2 -SaO 2 ), precision (standard deviation of the difference), and accuracy (root-mean-square error [A RMS ]). During conditions of low perfusion (Pi ≤ 1, range [0.1 to 1]), overall bias and precision were + 0.48% ± 1.59%, while bias and precision were + 0.19 ± 1.53%, and + 0.91 ± 1.57%, for Black and White subjects, respectively., Results:  During normal perfusion (Pi > 1, range [1 to 12]), overall bias and precision were + 0.18% ± 1.34%, while bias and precision were -0.26 ± 1.37%, and - 0.12 ± 1.31%, for Black and White subjects, respectively. A RMS was 1.37% in all subjects with normal perfusion and 1.64% in all subjects with low perfusion., Conclusion:  Masimo SET® pulse oximeters with RD SET® sensors are accurate for individuals of both Black and White races when Pi is normal, as well as during conditions when Pi is low. The A RMS for all conditions studied is well within FDA standards. This study was conducted in healthy volunteers during well-controlled laboratory desaturations, and results could vary under certain challenging clinical conditions., (© 2024. The Author(s).)

Background: Effective pain assessment is crucial to tailor the analgesic regimen post-operatively. Perfusion index (PI) has been reported to be a useful objective assessment tool for monitoring pain. This study aimed to explore the utility of PI in assessing postoperative pain in upper limb surgeries under supraclavicular block and its correlation with visual analogue scale (VAS) scores., Methods: This prospective, observational study included 140 patients scheduled for elective upper limb surgeries. PI, VAS scores, heart rate (HR), mean arterial pressure (MAP) and physiological parameters were recorded at baseline and postoperatively. Inj. tramadol was administered when the VAS score exceeded ≥ 4 and the VAS score, PI, HR and MAP were recorded at 5, 10, 15 and 20 minutes after administration. Comparison of normally and non-normally distributed data was done using t-statistics and Mann-Whitney U-test respectively. Pearson correlation was used to establish a correlation between variables and the receiver operating characteristic (ROC) curve was used to calculate the cut-off value of PI to determine the onset of pain., Results: There was a significant and moderate correlation between pre-analgesic and post-analgesic PI and VAS score (r = -0.425 and -0.448 respectively, p<0.001), while PI and MAP or PI and HR showed only a weak correlation. A cut-off value of 14.7 for PI showed 76.3% sensitivity and 100% specificity in predicting rescue analgesia requirements., Conclusion: The study supports the use of PI as an objective measure for postoperative pain assessment, with a notable correlation with VAS scores. The identified cut-off value for PI adds to its clinical utility in predicting the need for rescue analgesia., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Bihani et al.)

Background: Tracking preload dependency non-invasively to maintain adequate tissue perfusion in the perioperative period can be challenging.The effect of phenylephrine on stroke volume is dependent upon preload. Changes in stroke volume induced by phenylephrine administration can be used to predict preload dependency. The change in the peripheral perfusion index derived from photoplethysmography signals reportedly corresponds with changes in stroke volume in situations such as body position changes in the operating room. Thus, the peripheral perfusion index can be used as a non-invasive potential alternative to stroke volume to predict preload dependency. Herein, we aimed to determine whether changes in perfusion index induced by the administration of phenylephrine could be used to predict preload dependency., Methods: We conducted a prospective single-centre observational study. The haemodynamic parameters and perfusion index were recorded before and 1 and 2 min after administering 0.1 mg of phenylephrine during post-induction hypotension in patients scheduled to undergo surgery. Preload dependency was defined as a stroke volume variation of ≥ 12% before phenylephrine administration at a mean arterial pressure of < 65 mmHg. Patients were divided into four groups according to total peripheral resistance and preload dependency., Results: Forty-two patients were included in this study. The stroke volume in patients with preload dependency (n = 23) increased after phenylephrine administration. However, phenylephrine administration did not impact the stroke volume in patients without preload dependency (n = 19). The perfusion index decreased regardless of preload dependency. The changes in the perfusion index after phenylephrine administration exhibited low accuracy for predicting preload dependency. Based on subgroup analysis, patients with high total peripheral resistance tended to exhibit increased stroke volume following phenylephrine administration, which was particularly prominent in patients with high total peripheral resistance and preload dependency., Conclusion: The findings of the current study revealed that changes in the perfusion index induced by administering 0.1 mg of phenylephrine could not predict preload dependency. This may be attributed to the different phenylephrine-induced stroke volume patterns observed in patients according to the degree of total peripheral resistance and preload dependency., Trial Registration: University Hospital Medical Information Network (UMIN000049994 on 9/01/2023)., (© 2024. The Author(s).)

The study aimed to assess the pleth variability index (PVI) in patients undergoing lumbar disc herniation surgery under general and spinal anesthesia, exploring its correlation with fluid responsiveness, position, and hemodynamic parameters. Methods: This prospective study included 88 ASA 1-2 patients, aged 18-65, undergoing 1-3 h elective lumbar disc herniation surgery. Patients in groups GA and SA were observed for demographic, operative, and hemodynamic parameters at specified time points. (3) Results: PVI values were comparable between the GA and SA groups. After 250 mL of fluid loading, both groups showed a significant decrease in basal PVI at T2. Prone positions in GA exhibited higher PI values than in SA. The transition from a prone to supine position maintained PVI, while pulse and MAP decreased.; (4) Conclusions: PVI values were comparable in elective lumbar disc herniation surgery with general and spinal anesthesia. Both groups exhibited significant a PVI decrease at T2 after 250 mL of fluid loading, indicating fluid responsiveness. In general anesthesia, the prone position showed a lower MAP and higher PI values compared to spinal anesthesia. PVI and PI, sensitive to general anesthesia changes, could have beneficial additions to standard hemodynamic monitoring in spinal anesthesia management.

Background: Passive leg raising (PLR) reliably predicts fluid responsiveness but requires a real-time cardiac index (CI) measurement or the presence of an invasive arterial line to achieve this effect. The plethysmographic variability index (PVI), an automatic measurement of the respiratory variation of the perfusion index, is non-invasive and continuously displayed on the pulse oximeter device. We tested whether PLR-induced changes in PVI (ΔPVI PLR ) could accurately predict fluid responsiveness in mechanically ventilated patients with acute circulatory failure., Methods: This was a secondary analysis of an observational prospective study. We included 29 mechanically ventilated patients with acute circulatory failure in this study. We measured PVI (Radical-7 device; Masimo Corp., Irvine, CA) and CI (Echocardiography) before and during a PLR test and before and after volume expansion of 500 mL of crystalloid solution. A volume expansion-induced increase in CI of >15% defined fluid responsiveness. To investigate whether ΔPVI PLR can predict fluid responsiveness, we determined areas under the receiver operating characteristic curves (AUROCs) and gray zones for ΔPVI PLR ., Results: Of the 29 patients, 27 (93.1%) received norepinephrine. The median tidal volume was 7.0 [IQR: 6.6-7.6] mL/kg ideal body weight. Nineteen patients (65.5%) were classified as fluid responders (increase in CI > 15% after volume expansion). Relative ΔPVI PLR accurately predicted fluid responsiveness with an AUROC of 0.89 (95%CI: 0.72-0.98, p < 0.001). A decrease in PVI ≤ -24.1% induced by PLR detected fluid responsiveness with a sensitivity of 95% (95%CI: 74-100%) and a specificity of 80% (95%CI: 44-97%). Gray zone was acceptable, including 13.8% of patients. The correlations between the relative ΔPVI PLR and changes in CI induced by PLR and by volume expansion were significant (r = -0.58, p < 0.001, and r = -0.65, p < 0.001; respectively)., Conclusions: In sedated and mechanically ventilated ICU patients with acute circulatory failure, PLR-induced changes in PVI accurately predict fluid responsiveness with an acceptable gray zone., Trial Registration: ClinicalTrials.govNCT03225378., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Significance: Diffuse correlation spectroscopy (DCS) permits non-invasive assessment of skeletal muscle blood flow but may misestimate changes in muscle perfusion., Aim: We aimed to highlight recent evidence that DCS blood flow index (BFI) misestimates changes in muscle blood flow during physiological perturbation and to introduce a novel approach that adjusts BFI for estimated changes in vasodilation., Approach: We measured changes in muscle BFI during quadriceps and forearm exercises using DCS, the latter of which were adjusted for estimated changes in microvascular flow area and then compared to Doppler ultrasound in the brachial artery. Then, we compared adjusted BFI- and arterial spin labeling (ASL) MRI measures of gastrocnemius blood flow during reactive hyperemia and plantar flexion exercise., Results: We observed little-to-no change in quadriceps BFI during maximal-effort exercise. Similarly, forearm BFI was modestly increased during handgrip exercise, but the magnitude was significantly lower than measured by Doppler ultrasound in the brachial artery. However, this difference was ameliorated after adjusting BFI for estimated changes in microvascular flow area. Similar observations were also observed in the gastrocnemius when directly comparing the adjusted BFI values to ASL-MRI., Conclusions: Adjusting BFI for estimated changes in microvascular flow area may improve DCS estimates of muscle blood flow, but further study is needed to validate these methods moving forward., (© 2024 The Authors.)

Objectives: The IKORUS system (Vygon, Écouen, France) allows continuous monitoring of the urethral perfusion index (uPI) using a photoplethysmographic sensor mounted near the base of the balloon of a dedicated urinary catheter. We aimed to test the hypothesis that the uPI decreases during off-pump coronary artery bypass (OPCAB) surgery and to investigate the relationship between the uPI and macrocirculatory variables., Design: Prospective observational study., Setting: University Medical Center Hamburg-Eppendorf, Hamburg, Germany., Participants: Twenty patients having OPCAB surgery., Interventions: None., Measurements and Main Results: The primary endpoint was changes in the uPI during OPCAB surgery. We additionally investigated associations between the uPI and cardiac output, mean arterial pressure, heart rate, and point-of-care variables. Twenty patients with 24,137 uPI measurements were included. Overall, there was a high interindividual variability in the uPI. Compared with the preparation phase (during which the median [interquartile range] uPI was 7.7 [5.6-12.0]), the uPI decreased by 14% (95% CI 13%-15%) during the bypass grafting phase, by 35% (95% CI 34%-36%) during the cardiac positioning phase, and by 7% (95% CI 6%-9%) during hemostasis. There was no clinically important association between uPI and either cardiac output, mean arterial pressure, or heart rate., Conclusions: The uPI decreases during OPCAB surgery, specifically during the cardiac positioning phase. There was no clinically important association between uPI and either cardiac output, mean arterial pressure, or heart rate. It, therefore, remains to be determined whether intraoperative uPI decreases are clinically important, reflect alterations in intra-abdominal tissue perfusion that are not reflected by systemic macrohemodynamics, and can help clinicians guide therapeutic interventions., Competing Interests: Declaration of Competing Interest M.F. is a consultant for Edwards Lifesciences (Irvine, CA) and has received institutional restricted research grants and honoraria for consulting and giving lectures from CNSystems Medizintechnik GmbH (Graz, Austria). K.K. is a consultant for and has received honoraria for giving lectures from Edwards Lifesciences (Irvine, CA). K.K. is a consultant for Vygon (Aachen, Germany). BS is a consultant for and has received institutional restricted research grants and honoraria for giving lectures from Edwards Lifesciences (Irvine, CA, USA). BS is a consultant for Philips North America (Cambridge, MA, USA) and has received honoraria for giving lectures from Philips Medizin Systeme Böblingen (Böblingen, Germany). BS has received institutional restricted research grants and honoraria for giving lectures from Baxter (Deerfield, IL, USA). BS is a consultant for and has received institutional restricted research grants and honoraria for giving lectures from GE Healthcare (Chicago, IL, USA). BS has received institutional restricted research grants and honoraria for giving lectures from CNSystems Medizintechnik (Graz, Austria). BS is a consultant for Maquet Critical Care (Solna, Sweden). BS has received honoraria for giving lectures from Getinge (Gothenburg, Sweden). BS is a consultant for and has received institutional restricted research grants and honoraria for giving lectures from Pulsion Medical Systems (Feldkirchen, Germany). BS is a consultant for and has received institutional restricted research grants and honoraria for giving lectures from Vygon (Aachen, Germany). BS is a consultant for and has received institutional restricted research grants from Retia Medical (Valhalla, NY, USA). BS has received institutional restricted research grants from Osypka Medical (Berlin, Germany). BS was a consultant for and has received institutional restricted research grants from Tensys Medical (San Diego, CA, USA). BS is an Editor of the British Journal of Anaesthesia., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Perfusion index (PI) and CRIB (Clinical risk index of babies) Score II both are minimally invasive tools for prediction of mortality and morbidity in sick neonates. This study aims to know the predictive values of both PI and CRIB Score II in assessment of severity of illness in preterm neonates of 28 to 32 weeks and their correlation., Methods: PI and CRIB II Score of 125 sick preterm neonates admitted in NICU were assessed within 12 hours of admission. Severity noted in form of outcome. Correlation between PI and CRIB Score II were observed., Results: Receiver operating characteristic (ROC) curve were plotted for PI and CIRB Score II with outcome (discharged vs expired). Area under curve for perfusion index was 0.776 at 95% confidence interval. Optimum cutoff point based on ROC curve was 1.65 with sensitivity of 84%., specificity of 37.2% with positive predictive value of 70% and negative predictive value of 57%. Area under curve for CRIB Score II was 0.622 (p value < 0.028), optimum cut off point based on ROC curve for CRIB II score was 3.5 with sensitivity 79.10% of specificity of 40% positive predictive value is 43.03% and negative predictive value of 76.9%. Spearman's correlation coefficient between PI and CRIB II score was -0.272 and p value is 0.002., Conclusion: This study concluded that perfusion index (p < 0.001) is better for predicting the severity compared to CRIB II score (p < 0.028). A weak negative correlation exists between PI and CRIB II score (r = -0.272).

Background and Objectives: Spinal anesthesia is the technique of choice for elective cesarean section with a prominent side effect of postspinal anesthesia hypotension (PSH). This needs an early prediction to avoid feto-maternal complication. This study aimed to assess the diagnostic accuracy of perfusion index (PI) and inferior vena cava collapsibility index (IVCCI) in the prediction of PSH., Material and Methods: Thirty parturients of American Society of Anesthesiologists Physical Status (ASA-PS) 1 and two undergoing cesarean delivery participated in the study. IVCCI, PI, baseline systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), and heart rate (HR) were noted in the preoperative period. The fall of MBP by 20% from baseline or below 65 mm Hg was considered PSH. After spinal anesthesia, SBP, DBP, MBP, and HR were noted again for diagnosing PSH., Results: It did not show any statistical difference when comparing the PI between the PSH and non-PSH groups in both the PSH definition groups. IVCCI was significantly higher when PSH was considered MBP <65 mm Hg ( P = 0.01). However, IVCCI was found to be statistically insignificant if PSH was considered a 20% reduction in baseline MBP. The correlation matrix between IVCCI and PI showed Pearson's r-value of 0.525, indicating a substantial relationship between the two ( P = 0.003). Multivariate logistic regression analysis had shown that neither IVCCI nor PI was a good predictor of PSH in parturients for both definition groups for PSH., Conclusion: Although there is a modest correlation between PI and IVCCI, both cannot be used to predict postspinal hypotension in parturients undergoing elective lower-segment cesarean section (LSCS)., Competing Interests: There are no conflicts of interest., (Copyright: © 2023 Saudi Journal of Anesthesia.)

Background and Aims: Caudal block is among the most widely administered regional anesthesia in pediatric patients. The clinical signs and objective assessments are not fast and reliable enough to provide a good feedback. Perfusion index (PI) is considered as a sensitive marker to assess the efficacy of caudal block. We aim to assess PI as an indicator for success of caudal block in pediatric patients., Material and Methods: Sixty pediatric patients scheduled for elective surgery of lower abdomen and below were included. Patients were randomly allocated into two groups (n = 30): Group 1 received caudal block after general anesthesia and Group 2 only received general anesthesia. PI, heart rate, mean arterial pressure, and anal sphincter tone (AST) were recorded at 5, 10, 15, and 20 min following induction of anesthesia., Results: A persistent increase in the PI value was observed in Group 1 starting from 5 min till 20 min, as compared to Group 2, at all the time intervals. When mean PI was statistically compared between both the groups, it was found to be highly significant ( P = 0.001). Group 1 patients have progressive laxity of AST which was found to be significantly different from Group 2 ( P < 0.001)., Conclusion: We have found that both PI and AST are good indicators for assessing success of caudal block onset in pediatric patients but AST took slightly longer time (~20 mins). Therefore, we conclude that PI is simple, economical, and noninvasive monitor that predicts the caudal onset much earlier than AST., Competing Interests: There are no conflicts of interest., (Copyright: © 2023 Journal of Anaesthesiology Clinical Pharmacology.)

Background: Monitoring replanted digits remains a challenging task in microsurgical units. Previous studies have indicated the perfusion index (PI), a parameter directly proportional to the blood flow, might be a useful tool., Objective: The PI is evaluated as a monitoring tool in patients with replanted digits., Methods: This prospective, non-interventional study includes 31 patients with revascularized or replanted digits. After successful revascularization or replantation, the PI and peripheral oxygen saturation of the affected finger and its contralateral equivalent were measured simultaneously. The values were detected by the device Radical-97® Pulse CO-Oximeter® (Masimo Corporation, 52 Discovery, Irvine, CA 92618, USA)., Results: The median PI of affected fingers was 3.5±0.56 for revascularized and 2.2±0.8 for replanted fingers. The difference between the PI values of replanted digits and the healthy contralateral side was highly significant (p < 0.0001). The area under the curve in the receiver operating characteristics was 0.92 for a PI difference > 80.49% and predicted a loss of replant with a specificity of 100% and a sensitivity of 75%., Conclusion: The assessment of the PI in patients with reperfusion of a vascular compromised digit is a useful tool to continuously monitor peripheral perfusion. The dynamic behavior of the PI is essential to detect perfusion disturbance.

Background: The erector spinae plane block (ESPB), which was introduced for the management of thoracic pain, is a technically easy and relatively noninvasive ultrasound (ULSD)-guided technique. Although the ESPB is used widely in variable clinical situations, its sympatholytic effect has never been studied., Objectives: The purpose of this study is to demonstrate the sympatholytic effect of the high thoracic ESPB by comparing the blocked and unblocked sides of patients' upper extremities, using the changes in the perfusion index (PI)., Study Design: Prospective, single-group, and open-label study., Setting: The study was carried out in the pain clinic of a tertiary university hospital., Methods: This study included 47 patients with upper extremity pain and various diseases who received T2 or T3 ESPBs using 20 mL of 0.2% ropivacaine. For the evaluation of the sympatholytic effect, measurements were taken on the numeric rating scale (NRS), the neck disability index (NDI), and the PI., Results: The PIs of the blocked sides demonstrated significant increases at 10, 20, and 30 minutes compared to the PIs of the baseline and unblocked sides (P < 0.001). The PI ratio at 10 minutes was 2.74 ± 1.65, which was the highest value during the measurement period. Until 30 minutes after the ESPB, the PI ratio was significantly higher in the blocked side than in the unblocked side. During the study period, significant reductions in NRS and NDI scores were found irrespective of disease entity., Limitation: The period of PI measurement was only 30 minutes, so we could not determine the time point when the PI returned to the baseline value., Conclusion: The high thoracic ESPB was effective in relieving upper extremity pain in diverse disease entities, and the PIs of patients' blocked sides demonstrated significant increases over the baseline value and contralateral unblocked sides.

Background: Prediction of fluid responsiveness in hypotensive patients is a challenge. The correlation between a novel noninvasive dynamic indicator, Pleth Variability Index (PVI ®), and a gold-standard Systolic Pressure Variation (SPV) as a measure of fluid responsiveness was assessed in the Intensive Care Unit (ICU) or Operation Theatre (OT) in a tertiary care hospital., Methods: A prospective experimental study was conducted over a span of one year on 100 mechanically ventilated patients with hypotension. Vital parameters along with SPV and PVI ® were recorded before and after a standard volume expansion protocol. A 10% SPV threshold was used to define fluid responders and nonresponders., Results: Pearson's correlation graph at baseline showed positive correlation between PVI ® and SPV (r = 0.59, p-value = 0.001). Strength of correlation was comparatively less but still showed positive correlation at 15 (r = 0.39, p-value = 0.009) and 30 (r = 0.404, p-value = 0.004) minutes of fluid bolus. The Bland Altman analysis of baseline values of PVI ® and SPV showed good agreement with a mean bias of 9.05. Percentage change of PVI ® and SPV over 30 min showed a statistically significant positive correlation in the responder group (r = 0.53, p < 0.05). A threshold value of PVI ® more than 18% before volume expansion differentiated fluid responders and nonresponders with a sensitivity of 75% and specificity of 67%, with an area under Receiver Operating Characteristic (ROC) of 0.78., Conclusion: A positive correlation exists between SPV and PVI ®, justifying the use of noninvasive PVI ® in a clinical setting of hypotension., Competing Interests: The authors have none to declare., (© 2021 Director General, Armed Forces Medical Services. Published by Elsevier, a division of RELX India Pvt. Ltd.)

Background: The erector spinae plane block (ESPB), which was introduced to manage the thoracic pain, is a technical easy and less invasive ultrasound-guided technique. Although the ESPB is used widely in various clinical situations, no studies have evaluated the association between the clinical outcomes of the ESPB and the numerical changes of the perfusion index (PI)., Objectives: The purpose of this study is to investigate the association between the clinical response following ESPB and other possible factors including the changes of PI., Study Design: Prospective, nonrandomized, and an open-label study., Setting: The pain clinic of a tertiary university hospital., Methods: This study included 91 patients of low back pain with degenerative spinal disease who received L4 ESPB using 20 mL of 0.2% ropivacaine. For the predication of clinical outcome, the PI was measured for 30 min at the blocked side subsequent to the ESPB. Various demographic data were also analyzed to predict the clinical outcomes., Results: The PI of the responder group was higher value than that of the nonresponder group until 30 min but did not show any statistically significant differences. Multivariate logistic regression analysis revealed that the duration of pain (odds ratio [OR], 0.95; 95% CI, 0.90-1.00; P = 0.043), the right side injection (OR, 3.87; 95% CI, 1.42-10.55; P = 0.008), and the PI ratio of 1.5-3 at 10 min (OR, 3.79; 95% CI, 1.36-10.57; P = 0.011), were independent factors associated with successful outcomes., Limitation: The responder and the nonresponders were categorized using only changes of the numeric rating scale. The categorization based on the changes of functional disability or quality of life was not used., Conclusion: The right side injection, duration of pain less than 3 months, PI ratio of 1.5-3 at 10 min following the ESPB were associated with successful clinical outcomes.

Background: To evaluate whether the use of norepinephrine during the management of patients with sepsis affects the perfusion index (PI) and patient outcomes. Methods: We retrospectively studied patients with septic shock between January 2014 and December 2018 who had undergone Pulse index Continuous Cardiac Output-Plus cardiac output monitoring and received norepinephrine during the management. We collected data regarding basic clinical characteristics. Hemodynamic parameters, including lactate, PI, and norepinephrine dose at T0 and 24 h after Pulse index Continuous Cardiac Output catheterization (T24) were obtained. Results: The PI of the nonsurvivor group (n  =  44) was significantly lower than that of the survivor group (n  =  144) at T24, and the lactate level of the nonsurvivor group was significantly higher than that of the survivor group. The multiple logistic regression analysis suggested that the norepinephrine dose and PI were the most independent risk and protective factors, respectively, for intensive care unit mortality. The area under the curve for a poor prognosis was 0.847 (95% confidence interval, 0.782-0.912). The optimal cutoff value of the PI at T24 to predict intensive care unit mortality was 0.6, with a sensitivity of 77.1% and a specificity of 80%. Based on this optimal cutoff value, we divided patients into groups with PI ≥ 0.6 (n  =  125) and PI < 0.6 (n  =  59). The lactate level of the PI < 0.6 group was higher than that of the PI ≥ 0.6 group at T24. The PI < 0.6 group showed a significantly higher sublingual dose of norepinephrine indicators than the PI ≥ 0.6 group. The PI showed a strong negative correlation with norepinephrine dose (r  =  -0.344, P  < .001) and lactate (r  =  -0.291, P  < .001). Conclusions: A higher PI is a protective factor, and a higher dose of norepinephrine is a risk factor for the prognosis of critically ill patients with septic shock. A lower PI was associated with a higher dose of norepinephrine., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Introduction: cardiac surgery associated acute kidney injury (CSA-AKI) has a number of preoperative and intraoperative risk factors. Cardiopulmonary bypass (CPB) factors have not yet been elucidated in a single multivariate model. The aim of this study is to develop a dynamic predictive model for CSA-AKI., Methods: retrospective study on 910 consecutive adult cardiac surgery patients. Baseline data were used to settle a preoperative CSA-AKI risk model (static risk model, SRM); CPB related data were assessed for association with CSA-AKI. CPB duration, nadir oxygen delivery, time of exposure to a low oxygen delivery, nadir mean arterial pressure, peak lactates and red blood cell transfusion were included in a multivariate dynamic perfusion risk (DPR). SRM and DPR were merged into a final logistic regression model (multifactorial dynamic perfusion index, MDPI). The three risk models were assessed for discrimination and calibration., Results: the SRM model had an AUC of 0.696 (95% CI 0.663-0.727), the DPR model of 0.723 (95% CI 0.691-0.753), and the MDPI model an AUC of 0.769 (95% CI 0.739-0.798). The difference in AUC between SRM and DPR was not significant ( p = 0.495) whereas the AUC of MDPI was significantly larger than that of SRM ( p = 0.004) and DPR ( p = 0.015)., Conclusions: inclusion of dynamic indices of the quality of CPB improves the discrimination and calibration of the preoperative risk scores. The MDPI has better predictive ability than the existing static risk models and is a promising tool to integrate different factors into an advanced concept of goal-directed perfusion., Competing Interests: Declaration of conflicting interestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Marco Ranucci is a Consultant for Livanova and Medtronic; Mauro Cotza is a Consultant for Livanova, Medtronic, and Qura. The algorhitms composing the Multifactorial Dynamic Perfusion Index are protected by a patent owned by IRCCS Policlinico San Donato.

Objectives: To study in children with septic shock: 1) variation in peripheral perfusion index (PI), which is a derived variable from pulse oximetry; 2) correlation between PI and lactate concentration; and 3) exploratory diagnostic evaluation between mortality and PI., Design: Prospective observational study (from October 2018 to March 2020)., Setting: Pediatric emergency department and PICU of a tertiary hospital in India., Patients: Children (1 mo to 16 yr old) with septic shock., Interventions: None., Measurements and Main Results: Data collected included demographic, clinical, laboratory, and outcome-related variables. Hemodynamic variables like heart rate, mean arterial pressure, and PI, along with serum lactate were recorded at specified intervals. A total of 112 children with septic shock were recruited, with median (interquartile range [IQR]) age of 50 (IQR 12,118.5) months and 65 of 112 (58%) were male children. Overall mortality was 25 of 112 (22%). At admission, the median PI was 0.6 (IQR -0.30, 0.93), and we used PI less than or equal to 0.6 to define a "critical PI." Of 61 children with critical PI at admission, 26 of 61 increased above this threshold by 6 hours. We observed a negative correlation between PI and lactate, at admission ( r = -0.27; 95% CI, -0.44 to -0.08; p = 0.006) and at 6 hours ( r = -0.21; 95% CI, -0.39 to -0.02; p = 0.03). In the exploratory analysis, a PI cutoff of less than or equal to 0.6 at 6 hours had area under the receiver operating curve of 0.74 (95% CI, 0.60-0.88). That is, with a 70% sensitivity and 81% specificity for mortality, the performance of such a test in our population (pre-to-post-test probability) for mortality would be 0.22-0.51., Conclusions: We have used pulse oximetry-derived PI in children presenting with septic shock and found that the value is negatively correlated with a rise in serum lactate concentration. However, the utility of using a critical threshold value in PI (≤ 0.6) after 6 hours of treatment to be indicative of later mortality has considerable uncertainty., Competing Interests: The authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2023 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies.)

Background: During cardiopulmonary resuscitation (CPR), some parameters (e.g., intraarterial pressure measurement and end-tidal carbon dioxide (EtCO 2 )) indicate the quality and outcome of resuscitation. These parameters are generally based on monitoring the hemodynamic status. Perfusion index (PI) is a calculation from the photoplethysmography (PPG) signal and displays the proportion of pulsatile to non-pulsatile light absorption or reflection in the PPG signal. It helps to evaluate cardiac output and tissue perfusion in the care of a critical patient. Its most important advantages are that it can be easily measured with a pulse oximeter probe attached to the finger (non-invasive), can be objectively repeated, can be applied quickly, and is inexpensive. Normal PI values range from 0.2% to 20%. Despite being recognized as a valuable indicator of hemodynamics, there is limited information regarding its relevance in patients experiencing cardiac arrest. Although the PI is known to be a valuable parameter to indicate hemodynamics, information about its value in cardiac arrest patients is limited. This study aims to evaluate the performance of PI and EtCO 2 in predicting the return of spontaneous circulation (ROSC) among cardiac arrest patients., Methods: This was a single-center, prospective, observational clinical study including both out-of-hospital and in-hospital adult cardiac arrest patients. The study was conducted from November 1, 2018 to April 30, 2019 at the Emergency Department (ED) of the Hacettepe University Hospital, Ankara, Turkey. The EtCO 2 values of the patients were recorded at the time they were intubated (t 0 ) and every five minutes (t 5 , t 10 , t 15 ...) during CPR. Along with these measurements, PI values were measured with the Masimo Signal Extraction Technology device (Masimo, California, United States). The study's primary outcome was PI's performance in predicting the ROSC among cardiac arrest patients. The secondary outcomes of the study were the performance of EtCO 2 in predicting the ROSC among cardiac arrest patients and the association between PI and EtCO 2 values., Results: We included a total of 100 cases. The mean age of patients was 70.4 ± 13.4 years, and 65% were male. The ROSC was achieved in 29 patients. There was no statistical difference in PI values between the ROSC (+) and ROSC (-) groups at any minute. However, in the ROSC (+) group, EtCO 2 values were observed to be high starting from the fifth minute (t 5 , p=0.010; t 10 , p<0.001; t 15 , p=0.014; t 20 , p=0.033; t 25 , p=0.003, respectively). There was no correlation between the PI and EtCO 2 values at 0, 5, 10, 15, 20, and 25 minutes (t 0 , p=0.436; t 5 , p=0.154; t 10 , p=0.557; t 15 , p=0.740; t 20 p=0.241; t 25 p=0.201, respectively)., Conclusion: Measuring PI values during resuscitation in intubated cardiac arrest patients does not help clinicians predict the outcome. In addition, no correlation was found with EtCO 2 values. However, EtCO 2 values remained high in patients with the ROSC from the fifth minute onward. Further larger-scale studies are needed regarding the optimal use of PI in cardiac arrest patients., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Dogan et al.)

Objective: A topic of current research is the development of a new approach to the diagnosis and treatment of severe brain injury taking into consideration its main pathophysiological mechanism-idiopathic intracranial hypertension syndrome. The goal of this study was to identify Doppler patterns of unfavorable craniocerebral injury conditions to form a consistent algorithm of treatment measures to reduce secondary brain damage in patients with severe craniocerebral trauma., Methods: Transcranial Doppler imaging is a prospective method, which allows quick and noninvasive assessment of the intracerebral blood flow dynamics right at the patient's bedside. Due to the operator-dependent nature of this method, clinical interpretation can often be contradictory. As a result, no clear criteria for therapy correction have yet been formulated based on this neuroimaging method., Results: Analysis of the therapy performed allowed us to specify the options for the hyperosmolar solutions for the correction of idiopathic intracranial hypertension syndrome., Conclusions: No statistically significant difference in effectiveness was shown between mannitol and hypertonic saline solutions., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Induction of general anaesthesia is often accompanied by hypotension. Standard haemodynamic monitoring during anaesthesia relies on intermittent blood pressure and heart rate. Continuous monitoring systemic blood pressure requires invasive or advanced modalities creating a barrier for obtaining important information of the circulation. The Peripheral Perfusion Index (PPI) is obtained non-invasively and continuously by standard photoplethysmography. We hypothesized that different patterns of changes in systemic haemodynamics during induction of general anaesthesia would be reflected in the PPI. Continuous values of PPI, stroke volume (SV), cardiac output (CO), and mean arterial pressure (MAP) were evaluated in 107 patients by either minimally invasive or non-invasive means in a mixed population of surgical patients. 2 min after induction of general anaesthesia relative changes of SV, CO, and MAP was compared to the relative changes of PPI. After induction total cohort mean(± st.dev.) MAP, SV, and CO decreased to 65(± 16)%, 74(± 18)%, and 63(± 16)% of baseline values. In the 38 patients where PPI decreased MAP was 57(± 14)%, SV was 63(± 18)%, and CO was 55(± 18)% of baseline values 2 min after induction. In the 69 patients where PPI increased the corresponding values were MAP 70(± 15)%, SV 80(± 16)%, and CO 68(± 17)% (all differences: p < 0,001). During induction of general anaesthesia changes in PPI discriminated between the degrees of reduction in blood pressure and algorithm derived cardiac stroke volume and -output. As such, the PPI has potential to be a simple and non-invasive indicator of the degree of post-induction haemodynamic changes., (© 2023. The Author(s).)

Objective: The aim of this study was to observe the changes in pleth variability index (PVI), perfusion index (PI) and other hemodynamic parameters in adult individuals who had had Coronavirus disease 2019 (COVID-19) and were currently living a normal life. A further aim was to draw attention to the fact that some hemodynamic changes after COVID-19 may cause long-term health problems., Patients and Methods: A total of 174 adult individuals who had had COVID-19 and were currently living a normal life and 56 healthy individuals with similar demographic characteristics who had not had COVID-19 were included in the study. The PI, PVI, oxygen saturation (SpO2), pulse rate (PR), total hemoglobin (Hgb), oxygen reserve index (ORI), and blood pressure values were measured by Masimo Radical 7. The data of individuals who had and did not have COVID-19 before were compared., Results: The mean PVI (p = 0.008) and PI (p < 0.001) were significantly lower in people who had been exposed to COVID-19. Likewise, the mean of ORI, SpO2, and SpOC values was observed to be significantly lower in participants exposed to COVID-19 disease (p < 0.001, p < 0.001, and p = 0.006, respectively). The PVI had a positive correlation with body mass index (BMI) (r = 0.263, p < 0.001) and a negative correlation with SpO2 (r = -0.194, p = 0.003) and PR (r = 0.190, p = 0.004)., Conclusions: The PVI, PI, and other physiological parameters could potentially be useful for monitoring COVID-19 patients and evaluating their response to therapy. We believe that people who have been exposed to COVID-19 may be more susceptible to other diseases; therefore, they should be subjected to regular clinical checks.

Congenital heart defects (CHDs) are the most common neonatal malformations and are a leading cause of infant death in developed countries. Finding safe and effective diagnostic methods to screen for CHDs is important. The aim of this study was to evaluate the effectiveness of pulse oximetry (PO) and perfusion index (PI) in screening CHD. We conducted a systematic review of studies in PubMed, Embase, and the Cochrane Library published on or before October 1, 2021. Studies based on PICOS were included in this systematic review. The flow chart is made by PRISMA software. The quality of included studies was assessed by RevMan5 software (QUADAS-2: Quality Assessment of Diagnostic Accuracy Studies-2). The sensitivity, specificity, and other measurements of accuracy were pooled using Stata/SE 12.0 software. Five studies containing 46,965 neonates were included in this study. A randomized-effects model was used for the meta-analysis because of significant heterogeneity. The combined sensitivity and specificity were 0.82 (95% confidence interval [CI], 0.53-0.95) and 0.97 (95% CI, 0.57-1.00), respectively. The area under the curve was 0.92 (95% CI, 0.89-0.94). The combination PO and PI was significant in CHD screening. Once diagnosed by the combined method, it means that the neonate is most likely to have a CHD. KEY POINTS: · Pulse oximetry and PI screening.. · Congenital heart defects.. · A systematic review and meta-analysis.., Competing Interests: None declared., (Thieme. All rights reserved.)

Introduction: Transposition of great arteries is one of newborns' most common cyanotic CHDs, and its treatment is arterial switch operation in the first days of life. Low cardiac output syndrome may develop in the early postoperative period. In this study, we evaluated perfusion index and left ventricular output blood flow changes in patients who underwent arterial switch operation and developed low cardiac output syndrome., Methods: This study was conducted prospectively in newborns with transposition of great arteries who underwent arterial switch operation between 1st August 2020 and 1st August 2022. Low cardiac output syndrome score and left ventricular output were investigated. Initially, 6 th , 12 th , 18 th , and 24 th hour perfusion index and left ventricular output values of patients with and without low cardiac output syndrome were recorded. The results were evaluated statistically., Results: A total of 60 patients were included in the study. Sex distribution was equal. The median age at the time of surgery was 5 days (interquartile range 3-7 days), and the median weight was 3.1 kg (interquartile range 2.9-3. 4). Low cardiac output syndrome was detected in 30% (n = 18) of cases. The median perfusion index of patients who developed low cardiac output syndrome was significantly lower at the 12 th , 18 th , and 24 th hours (p < 0.05) (0.99 versus 1.25, 0.86 versus 1.21, and 0.96 versus 1.33, respectively). Similarly, the median left ventricular output of patients who developed low cardiac output syndrome was significantly lower at 12 th , 18 th , and 24 th hours (p < 0.05) (95 versus 110 ml/kg/min, 89 versus 109 ml/kg/min, and 92 versus 112 ml/kg/min, respectively). There was a significant correlation between perfusion index values and left ventricular output at all measurements (r > 0.500, p < 0.05)., Conclusion: Perfusion index and left ventricular output measurements decreased in newborns who developed low cardiac output syndrome after arterial switch operation, especially at 12 th and 18 th hours. Serial perfusion index and left ventricular output measurements can be instructive in predicting low cardiac output syndrome development.

Hemodynamic monitoring of neonates is crucial because neonates are easily and acutely susceptible to hemodynamic disturbances. As such, non-invasive monitoring of hemodynamics is preferable. It has been postulated that non-invasive pulse oximetry determines the perfusion index and pulse variability index and provides accurate measurements to predict hemodynamic changes in preterm or term infants. Equally, numerous studies have investigated the efficacy of perfusion and pulse variability indices in monitoring neonatal hemodynamics. The aim of this study was to systematically review studies that have delved into the role of perfusion and pulse variability indices in the assessment of neonatal hemodynamics. The study collected data from 2010-2023 using the patient, intervention, comparison, outcome (PICO) search strategy using the databases PubMed, Scopus, and Excerpta Medica database (Embase). A total of 616 articles were evaluated based on their appropriateness and relevance; we included seven studies. As per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a systematic review. Our study concluded that these indices were effective in measuring hemodynamics., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Mandala et al.)

Axillary nerve blocks are commonly using for forearm and hand surgery. Especially for finger replacement it has been shown continuous plexus blockade improves microcirculation. Addition to that benefit continuous blockade provides adequate analgesia. In this study perfusion index (PI) and plethysmographic variability index (PVI) changes were used to evaluate in blocks success. The PVI and PI values were detected by a Radical-7TM finger pulse oximetry device (Massimo Corp, USA) in both fingers of 50 plastic surgery patients, who received an axillary brachial plexus catheter before surgery. Data recorded at baseline, during catheter replacement, after catheter replacement, and before surgery. All periods hemodynamic data, visual analog scala, Ramsey sedation score and patient satisfaction score were collected. In all 110 patients blocks were successfully applied, PI values in blocked arm increased after local analgesic application (during catheter replacement), (P < .05), PVI values were decreased in the same period but there were no statistical significance. The PI increases after peripheral plexus blockade and may be used as an indicator for successful block placement in awake patient. And also, it may be used as an indicator for catheter effectiveness after surgery. But PVI values cannot detect that kind of relation with nerve blockade., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: The perfusion index (PI) is an objective method used to determine a successful nerve block. This study aimed to investigate the prognostic ability of the PI for a successful adductor canal nerve block (ACB) and suggest the optimal PI cut-off value for predicting a block., Methods: This study was a prospective observational study and enrolled a total of 39 patients. The patients were dichotomized into successful and inappropriate ACB groups according to the results of the sensation tests. The PI value, Pleth variability index (PVi) value, and heart rate were recorded one minute before the block, at the time of the block, and one to 30 min after the block at one-minute intervals. Delta (dPI), which was defined as the difference in PI value from the baseline (the value one minute before the block), was the primary outcome. The area under the receiver operating characteristic curve (AUROC) was calculated to determine the dPI prognostic accuracy and optimal cut-off value., Results: Successful ACB was achieved in 33 patients, while ACB was inappropriate in six patients. The dPI showed significant differences between the two groups under the time interval measured ( p = 0.001). The dPI at 5 and 20 min showed good prognostic ability for a successful block, with optimal cut-off values of 0.33 (AUROC: 0.725, 95% CI 0.499-0.951) and 0.64 (AUROC: 0.813, 95% CI 0.599-1.000), respectively., Conclusions: The dPI is an effective predictor of successful ACB. The suggested dPI cut-off values at 5 and 20 min were below 0.33 and 0.64, respectively.

Objective: The perfusion index (PI) is a noninvasive marker derived from photoelectric plethysmographic signals in pulse oximetry in the evaluation of peripheral perfusion. This study was aimed to determine the correlation between PI and left ventricular output (LVO) in healthy late preterm infants at 48 th hour of life., Study Design: With new generation pulse oximeter (MASIMO Rad 7 Oximeter) pre- and post-ductal PI values were recorded from healthy late preterm babies at the 48 th hour of life. PI was determined simultaneously with LVO as measured by transthoracic echocardiography., Results: A total of 50 late preterm babies were included in the study. The mean gestational age of the cases was 35.4 ± 0.7 weeks and the birth weight was 2,586 ± 362 g. Mean pre- and post-ductal PI values at the postnatal 48 th hour of babies' life were found to be 2.0 ± 0.9 and 1.7 ± 1.1. The mean LVO value was 438 ± 124, LVO/kg 175 ± 50. When the LVO value was normalized according to the babies' body weight, there was no statistically significant correlation between the pre- and post-ductal PI and the LVO/kg value ( r <0.2, p >0.05 in both comparisons)., Conclusion: There was no correlation between pre- and post-ductal PI and LVO values in healthy late preterm infants. This may be due to the failure of the LVO, a systemic hemodynamic parameter, to accurately reflect microvascular blood flow due to incomplete maturation of the sympathetic nervous system involved in the regulation of peripheral tissue perfusion in preterm babies., Key Points: · No correlation found between PI and LOV in preterm babies.. · LVO cannot adequately reflect peripheral blood flow.. · Sympathetic nervous system is immature in preterm infants.., Competing Interests: None declared., (Thieme. All rights reserved.)

Aim: (i) To compare perfusion index (PI) and plethysmography variability index (PVI) between neonates with proven or probable sepsis versus no-sepsis, (ii) to examine an association of PI and PVI with in-hospital mortality., Methods: We enrolled neonates with clinically presumed sepsis. Culture-proven or probable sepsis were categorised as 'cases' and no-sepsis as 'controls'. PI and PVI were recorded hourly for 120 h and averaged in 20-time epochs (0-6 h to 115-120 h)., Results: We analysed 148 neonates with sepsis (proven sepsis = 77, probable sepsis = 71) and 126 with no-sepsis. Neonates with proven/probable sepsis and no-sepsis had comparable PI and PVI values. Among 148 neonates with sepsis, 43 (29%) died. Non-survivors had significantly lower PI values than survivors (mean difference 0.21 [95% CI 0.14-0.29], p-value <0.001). PI had a significant but modest discriminative ability to identify non-survivors. However, PI did not independently predict mortality., Conclusion: Neonates with proven/probable sepsis and no-sepsis had comparable PI and PVI values in the first 120 h of sepsis. PI but not PVI values were significantly lower in non-survivors than survivors. PI did not independently predict in-hospital mortality. Due to modest discriminative ability, PI should be interpreted along with other vital signs to take clinical decisions., (© 2023 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)