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The incidence of aortic valve stenosis (AoS) increases with age, and once diagnosed, symptomatic severe AoS has a yearly mortality rate of 25%. AoS is diagnosed with transthoracic echocardiography (TTE), however, this gold standard is time consuming and operator and acoustic window dependent. As AoS affects the arterial blood pressure waveform, AoS-specific waveform features might serve as a diagnostic tool. Aim of the present study was to develop a novel, non-invasive, AoS detection model based on blood pressures waveforms. This cross-sectional study included patients with AoS undergoing elective transcatheter or surgical aortic valve replacement. AoS was determined using TTE, and patients with no or mild AoS were labelled as patients without AoS, while patients with moderate or severe AoS were labelled as patients with AoS. Non-invasive blood pressure measurements were performed in awake patients. Ten minutes of consecutive data was collected. Several blood pressure-based features were derived, and the median, interquartile range, variance, and the 1st and 9th decile of the change of these features were calculated. The primary outcome was the development of a machine-learning model for AoS detection, investigating multiple classifiers and training on the area under the receiver-operating curve (AUROC). In total, 101 patients with AoS and 48 patients without AoS were included. Patients with AoS showed an increase in left ventricular ejection time (0.02 s, p = 0.001), a delayed maximum upstroke in the systolic phase (0.015 s, p < 0.001), and a delayed maximal systolic pressure (0.03 s, p < 0.001) compared to patients without AoS. With the logistic regression model, a sensitivity of 0.81, specificity of 0.67, and AUROC of 0.79 were found. The majority of the population without AoS was male (85%), whereas in the population with AoS this was evenly distributed (54% males). Age was significantly (5 years, p < 0.001) higher in the population with AoS. In the present study, we developed a novel model able to distinguish no to mild AoS from moderate to severe AoS, based on blood pressure features with high accuracy. Clinical registration number: The study entailing patients with TAVR treatment was registered at ClinicalTrials.gov (NCT03088787, https://clinicaltrials.gov/ct2/show/NCT03088787). The study with elective cardiac surgery patients was registered with the Netherland Trial Register (NL7810, https://trialsearch.who.int/Trial2.aspx?TrialID=NL7810). [ABSTRACT FROM AUTHOR]

The quality of remote photoplethysmography (rPPG) signals presents a significant challenge in contactless optical blood pressure measurement. Feature and morphologybased approaches heavily rely on subtle changes in signal characteristics, but rPPG signals are highly susceptible to noise and interference. This study aims to evaluate rPPG signal quality by assessing correlation with a reference PPG and signal-to-noise ratio (SNR) across various color models and rPPG methods. Analyses are performed under different measurement conditions, accounting for common sources of signal artifacts. [ABSTRACT FROM AUTHOR]

Objectives: Systemic arterial hypertension is a common occurrence and can have serious adverse consequences in cats. Therefore, measuring blood pressure is very important. There are many indirect blood pressure measurement devices available. This study compared Doppler, oscillometric (petMAP Graphic II, SunTech Vet20, the Cardell Insight-X0000) and high-definition oscillometry devices for the non-invasive measurement of blood pressure in conscious cats. Methods: In this prospective study, blood pressure was measured in 32 cats using the different devices according to the recommendations of the American College of Veterinary Internal Medicine Consensus Statement. Blood pressures (systolic blood pressure [SBP], diastolic blood pressure [DBP], mean arterial pressure [MAP]), time to complete measurements, number of attempts needed, coefficient of variation (CV) between the blood pressure measurements of the different devices, ease of completing measurements and apparent stress level of the cat were assessed. Results: There was a significant difference between devices in the time taken to obtain blood pressure readings and the number of attempts necessary to obtain six reliable measurements. The CV of the Doppler device was significantly smaller than that of the rest of the devices, but there were no other differences between the devices. The mean SBP, DBP and MAP measured by the petMAP device were significantly higher than the measurements from the other devices. The perceived ease of measurement was not significantly different between the various machines. The perceived level of stress of measurement with the Doppler device was significantly higher compared with the other devices but did not lead to an increased SBP. Conclusions and relevance: Using a Doppler device to measure blood pressure in conscious cats is fast, relatively easy and gives reliable results. A disadvantage is that the Doppler device can only measure SBP, while oscillometric devices also provide DBP and MAP. However, in veterinary medicine, systolic hypertension is considered the most relevant. [ABSTRACT FROM AUTHOR]

BACKGROUND: Blood pressure (BP) monitoring is essential for patient care. Invasive arterial BP (IABP) is more accurate than non-invasive BP (NIBP), although the clinical significance of this difference is unknown. We hypothesized that IABP would result in a change of management (COM) among patients with non-hypertensive diseases in the acute phase of resuscitation. METHODS: This prospective study included adults admitted to the Critical Care Resuscitation Unit (CCRU) with non-hypertensive disease from February 1, 2019, to May 31, 2021. Management plans to maintain a mean arterial pressure >65 mmHg (1 mmHg=0.133 kPa) were recorded in real time for both NIBP and IABP measurements. A COM was defined as a discrepancy between IABP and NIBP that resulted in an increase/decrease or addition/discontinuation of a medication/infusion. Classification and regression tree analysis identified significant variables associated with a COM and assigned relative variable importance (RVI) values. RESULTS: Among the 206 patients analyzed, a COM occurred in 94 (45.6% [94/206]) patients. The most common COM was an increase in current infusion dosages (40 patients, 19.4%). Patients receiving norepinephrine at arterial cannulation were more likely to have a COM compared with those without (45 [47.9%] vs. 32 [28.6%], P=0.004). Receiving norepinephrine (relative variable importance [RVI] 100%) was the most significant factor associated with a COM. No complications were identified with IABP use. CONCLUSION: A COM occurred in 94 (45.6%) non-hypertensive patients in the CCRU. Receiving vasopressors was the greatest factor associated with COM. Clinicians should consider IABP monitoring more often in non-hypertensive patients requiring norepinephrine in the acute resuscitation phase. Further studies are necessary to confirm the risk-to-benefit ratios of IABP among these high-risk patients. [ABSTRACT FROM AUTHOR]

Background: The multiparameter monitor (MPM) is replacing mercury column sphygmomanometers (MCS) in acute care settings. However, data on the former's accuracy in critically ill children are scarce and mostly extrapolated from adults. We compared non-invasive blood pressure (NIBP) measurements by MPMs with MCS in pediatric intensive care unit (PICU). Patients: Adequately sedated and hemodynamically stabilized children (age, 1-144 months) were prospectively enrolled. Materials and methods: Three NIBP measurements were obtained from MCS (Diamond®, India) and MPM (Intellivue MX800® or Ultraview SL®) in rapid succession in the upper limb resting in supine position. Respective three measurements were averaged to obtain a paired set of NIBP readings, one each from MCS and MPM. Such readings were obtained thrice a day. NIBP readings were then compared, and agreement was assessed. Results: From 39 children [median age (IQR), 30 (10-72) months], 1,690 sets of NIBP readings were obtained. A-third of readings were from infants and children >96 months, while 383 (22.6%) readings were from patients on inotropes. Multiparameter monitors gave significantly higher NIBP readings compared to MCS [median systolic blood pressure (SBP), 6.5 (6.4-6.7 mm Hg); diastolic blood pressure (DBP), 4.5 (4.3-4.6 mm Hg); mean arterial pressure (MAP), 5.3 (5.1-5.4 mm Hg); p < 0.05]. It was consistent across age, gender, and critical care characteristics. Multiparameter monitors overestimated SBP in 80% of readings beyond the maximal clinically acceptable difference (MCAD). Conclusions: Non-invasive blood pressure readings from MCS and MPMs are not interchangeable; SBP was 6-7 mm Hg higher with the latter. Overestimation beyond MCAD was overwhelming. Caution is required while classifying systolic hypotension with MPMs. Confirmation with auscultatory methods is advisable. More studies are required to evaluate currently available MPMs in different pediatric age groups. [ABSTRACT FROM AUTHOR]

A six month old cross bred calf was presented with a swelling on lateral abdomen and diagnosed with lateral abdominal hernia, which underwent herniorrhaphy under general anaesthesia formed the subject of the study. The animal was administered with meloxicam @ 0.5 mg/kg body weight intravenously for pre-emptive analgesia. Thirty minutes later, xylazine @ 0.02 mg/kg and butorphanol @ 0.05 mg/kg, were administered intravenously. Upon sedation, the animal was administered with a loading dose of lignocaine @ 1 mg/kg body weight intravenously. Immediately following the loading dose of lignocaine, anaesthesia was induced using guaiphenesin @ 50 mg/kg and ketamine @ 2mg/kg intravenously. Following induction, anaesthesia was maintained using the prepared guaiphenesin-ketamine-lignocaine-butorphanol anaesthetic mixture as continuous rate infusion @ 3 ml/kg/hr. Indirect and direct blood pressure measurements were monitored and recorded. The non-invasive blood pressure values for systolic, diastolic and mean blood pressures did not differ significantly (p > 0.05) from those monitored invasively

Abstract Background Measuring blood pressure in patients with obesity is challenging. The ClearSight™ finger cuff (FC) uses the vascular unloading technique to provide continuous non-invasive blood pressure measurements. We aimed to test the agreement of the FC with invasive radial arterial monitoring (INV) in patients with obesity. Methods Participants had a body mass index (BMI) ≥45 kg/m2 and underwent laparoscopic bariatric surgery. FC and INV measurements were obtained simultaneously every 5 min on each patient, following induction of anesthesia. Agreement over time was assessed using modified Bland-Altman plots and error grid analysis permitted clinical interpretation of the results. Four-quadrant plots allowed assessment of concordance in blood pressure changes. Results The 30 participants had a median (IQR) BMI of 50.2 kg/m2 (IQR 48.3–55.3). The observed bias (SD, 95% limits of agreement) for systolic blood pressure (SBP) was 14.3 mmHg (14.1, -13.4 – 42.0), 5.2 mmHg (10.9, -16.0 – 26.5) for mean arterial pressure (MAP) and 2.6 mmHg (10.8, -18.6 – 23.8) for diastolic blood pressure (DBP). Error grid analysis showed that the proportion of readings in risk zones A-E were 90.8, 6.5, 2.7, 0 and 0% for SBP and 91.4, 4.3, 4.3, 0 and 0% for MAP, respectively. Discordance occurred in ≤8% of pairs for consecutive change in SBP, MAP and DBP. Conclusions The vascular unloading technique was not adequately in agreement with radial arterial monitoring. Evaluation in a larger sample is required before recommending this technique for intraoperative monitoring of patients with BMI ≥45 kg/m2.

Background and Aims: Non-invasive blood pressure (NiBP) varies with the arm and body position. In the lateral decubitus position (LDP), the non-dependent arm reads lower, and the dependent arm reads higher pressure. We aimed to study the correlation between the NiBP and invasive arterial blood pressure (ABP) as anaesthesia progressed and its correlation in different BP ranges. Methods: American Society of Anesthesiologists (ASA I–III) patients, between 18–70 years undergoing neurosurgical procedures in the LDP were studied. All were anaesthetised using a standard protocol, positioned in the LDP. NiBP was measured every 15 min in both dependent and non-dependent arms and correlated with the ABP. Results: Intra-class correlation (ICC) done between the dependent arm NiBP and ABP showed good correlation for mean and systolic BP and moderate correlation for diastolic BP. ICC was 0.800, 0.846 and 0.818 for mean and 0.771, 0.782, 0.792 for systolic BP at 15 min, 1 h, and 2 h, respectively. The ICC between the non-dependent arm NiBP and the invasive ABP showed poor correlation for all BP (systolic, diastolic and mean). As anaesthesia progressed, the mean difference between the NiBP and the ABP decreased in the dependent arm and increased in the non-dependent arm. The strength of agreement between the NiBP and the ABP in various BP ranges showed moderate correlation for the dependent arm NiBP (0.45–0.54) and poor correlation (0.21–0.38) for the non-dependent arm. Conclusion: The NiBP of the dependent arm correlated well with ABP in LDP under general anaesthesia (GA). It is better to defer measuring NiBP in the non-dependent arm as the correlation with ABP is poor.

Seth Hayes,1 Rebecca Miller,1 Ambrish Patel,2,3 Dmitry Tumin,1,2 Hina Walia,1 Mohammed Hakim,1 Faizaan Syed,1 Joseph D Tobias1,2,41Department of Anesthesiology and Pain Medicine, Nationwide Children’s Hospital, Columbus, OH 43205, USA; 2Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA; 3Division of Pediatric Critical Care, Nationwide Children’s Hospital, Columbus, OH 43205, USA; 4Department of Anesthesiology and Pain Medicine, The Ohio State University, Columbus, OH 43210, USACorrespondence: Seth HayesDepartment of Anesthesiology and Pain Medicine, Nationwide Children’s Hospital, 700 Children’s Drive, Columbus, OH 43205, USATel +1 614 722 4200Fax +1 614 722 4203Email seth.hayes@nationwidechildrens.orgPurpose: To compare invasive blood pressure (IBP) readings obtained from an arterial cannula with non-invasive blood pressure (NIBP) measurements from oscillometric cuffs on the upper and lower extremities of infants and children under general anesthesia.Patients and methods: Patients under 10 years of age were enrolled in our study if they were to receive general anesthesia with planned placement of a radial arterial cannula. At 5 mins intervals, IBP was measured using a fluid-coupled pressure transducer and NIBP was measured with two oscillometers with appropriately sized cuffs placed on the upper arm and lower leg, for 10 readings per patient.Results: The study enrolled 18 boys and 12 girls, ranging in age from 0 to 8 years. Across 300 data points, the absolute difference between the arm and invasive mean arterial pressure (MAP) measurements was 7±7 mmHg (range: 0–52 mmHg). The absolute difference between the leg and invasive MAP measurements was 8±8 mmHg (range: 0–52 mmHg). Although both non-invasive measurement sites demonstrated frequent deviation from invasive measurement, large deviations were more common when BP was measured at the leg (81 of 298 observations (27%) deviating by >10 mmHg) compared to the arm (60 of 300 observations (20%) deviating by >10 mmHg).Conclusion: The frequency of clinically significant NIBP deviation in children under general anesthesia supports the importance of IBP monitoring when hemodynamic fluctuations are likely and would be particularly detrimental. NIBP measured at the lower leg is more likely to result in clinically significant deviation from invasively measured MAP than NIBP values obtained from an upper arm.Keywords: invasive blood pressure, non-invasive blood pressure, blood pressure cuff

Background: Measuring blood pressure in patients with obesity is challenging. The ClearSight™ finger cuff (FC) uses the vascular unloading technique to provide continuous non-invasive blood pressure measurements. We aimed to test the agreement of the FC with invasive radial arterial monitoring (INV) in patients with obesity. Methods: Participants had a body mass index (BMI) ≥45 kg/m2 and underwent laparoscopic bariatric surgery. FC and INV measurements were obtained simultaneously every 5 min on each patient, following induction of anesthesia. Agreement over time was assessed using modified Bland-Altman plots and error grid analysis permitted clinical interpretation of the results. Four-quadrant plots allowed assessment of concordance in blood pressure changes. Results: The 30 participants had a median (IQR) BMI of 50.2 kg/m2 (IQR 48.3–55.3). The observed bias (SD, 95% limits of agreement) for systolic blood pressure (SBP) was 14.3 mmHg (14.1, -13.4 – 42.0), 5.2 mmHg (10.9, -16.0 – 26.5) for mean arterial pressure (MAP) and 2.6 mmHg (10.8, -18.6 – 23.8) for diastolic blood pressure (DBP). Error grid analysis showed that the proportion of readings in risk zones A-E were 90.8, 6.5, 2.7, 0 and 0% for SBP and 91.4, 4.3, 4.3, 0 and 0% for MAP, respectively. Discordance occurred in ≤8% of pairs for consecutive change in SBP, MAP and DBP. Conclusions: The vascular unloading technique was not adequately in agreement with radial arterial monitoring. Evaluation in a larger sample is required before recommending this technique for intraoperative monitoring of patients with BMI ≥45 kg/m2. [ABSTRACT FROM AUTHOR]

Background and Aims: Non-invasive blood pressure (NiBP) varies with the arm and body position. In the lateral decubitus position (LDP), the non-dependent arm reads lower, and the dependent arm reads higher pressure. We aimed to study the correlation between the NiBP and invasive arterial blood pressure (ABP) as anaesthesia progressed and its correlation in different BP ranges. Methods: American Society of Anesthesiologists (ASA I–III) patients, between 18–70 years undergoing neurosurgical procedures in the LDP were studied. All were anaesthetised using a standard protocol, positioned in the LDP. NiBP was measured every 15 min in both dependent and non-dependent arms and correlated with the ABP. Results: Intra-class correlation (ICC) done between the dependent arm NiBP and ABP showed good correlation for mean and systolic BP and moderate correlation for diastolic BP. ICC was 0.800, 0.846 and 0.818 for mean and 0.771, 0.782, 0.792 for systolic BP at 15 min, 1 h, and 2 h, respectively. The ICC between the non-dependent arm NiBP and the invasive ABP showed poor correlation for all BP (systolic, diastolic and mean). As anaesthesia progressed, the mean difference between the NiBP and the ABP decreased in the dependent arm and increased in the non-dependent arm. The strength of agreement between the NiBP and the ABP in various BP ranges showed moderate correlation for the dependent arm NiBP (0.45–0.54) and poor correlation (0.21–0.38) for the non-dependent arm. Conclusion: The NiBP of the dependent arm correlated well with ABP in LDP under general anaesthesia (GA). It is better to defer measuring NiBP in the non-dependent arm as the correlation with ABP is poor. [ABSTRACT FROM AUTHOR]

Since both, hypotension and hypertension, can potentially impair the function of vital organs such as heart, brain, or kidneys, monitoring of arterial blood pressure (BP) is a mainstay of hemodynamic monitoring in acutely or critically ill patients. Arterial BP can either be obtained invasively via an arterial catheter or non-invasively. Non-invasive BP measurement provides either intermittent or continuous readings. Most commonly, an occluding upper arm cuff is used for intermittent non-invasive monitoring. BP values are then obtained either manually (by auscultation of Korotkoff sounds or palpation) or automatically (e.g., by oscillometry). For continuous non-invasive BP monitoring, the volume clamp method or arterial applanation tonometry can be used. Both techniques enable the arterial waveform and BP values to be obtained continuously. This article describes the different techniques for non-invasive BP measurement, their advantages and limitations, and their clinical applicability.

Objective: To compare the simultaneous invasive and non-invasive measurements of blood pressure (IBP and NIBP) based upon the Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC II) database. Methods and results: A total of 986 records and 26,942 blood pressure (BP) measurements were extracted from MIMIC II database. The mean values of invasive systolic and invasive diastolic blood pressure (ISBP and IDBP) were 111.2 ± 33.9 mm Hg and 59.9 ± 22.8 mm Hg respectively, and the values of non-invasive ones were 114.0 ± 23.4 mm Hg and 51.0 ± 14.9 mm Hg. The average differences of systolic and diastolic blood pressure were −2.8 mm Hg and 8.9 mm Hg between IBP and NIBP. The correlation coefficients were 0.60 between ISBP and NISBP and 0.45 between IDBP and NIDBP. The robust regression equations between IBP (y) and NIBP (x) showed y = 1.02x − 2.95 for SBP (R2 = 0.60) and y = 0.77x + 18.43 for DBP (R2 = 0.82). At the higher part of BP, IBP is larger than NIBP, and at the lower part of BP, IBP is less than NIBP. Conclusion: Average invasive systolic blood pressure is lower than the non-invasive one and average invasive diastolic blood pressure is higher than the non-invasive one. The IBP shows good correlation with the NIBP. The invasive blood pressures can be estimated from non-invasive ones by the regression equations.

Objective To compare the simultaneous invasive and non-invasive measurements of blood pressure (IBP and NIBP) based upon the Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC II) database. Methods and results A total of 986 records and 26,942 blood pressure (BP) measurements were extracted from MIMIC II database. The mean values of invasive systolic and invasive diastolic blood pressure (ISBP and IDBP) were 111.2 ± 33.9 mm Hg and 59.9 ± 22.8 mm Hg respectively, and the values of non-invasive ones were 114.0 ± 23.4 mm Hg and 51.0 ± 14.9 mm Hg. The average differences of systolic and diastolic blood pressure were −2.8 mm Hg and 8.9 mm Hg between IBP and NIBP. The correlation coefficients were 0.60 between ISBP and NISBP and 0.45 between IDBP and NIDBP. The robust regression equations between IBP ( y ) and NIBP ( x ) showed y = 1.02 x − 2.95 for SBP ( R 2 = 0.60) and y = 0.77 x + 18.43 for DBP ( R 2 = 0.82). At the higher part of BP, IBP is larger than NIBP, and at the lower part of BP, IBP is less than NIBP. Conclusion Average invasive systolic blood pressure is lower than the non-invasive one and average invasive diastolic blood pressure is higher than the non-invasive one. The IBP shows good correlation with the NIBP. The invasive blood pressures can be estimated from non-invasive ones by the regression equations. [ABSTRACT FROM AUTHOR]

In humans, skin is a primary thermoregulatory organ, with vasodilation leading to rapid body cooling, whereas in Rodentia the tail performs an analogous function. Many thermodetection mechanisms are likely to be involved including transient receptor potential vanilloid-type 4 (TRPV4), an ion channel with thermosensitive properties. Previous studies have shown that TRPV4 is a vasodilator by local action in blood vessels, so here, we investigated whether constitutive TRPV4 activity affects Mus muscularis tail vascular tone and thermoregulation. We measured tail blood flow by pressure plethysmography in lightly sedated M. muscularis (CD1 strain) at a range of ambient temperatures, with and without intraperitoneal administration of the blood-brain barrier crossing TRPV4 antagonist GSK2193874. We also measured heart rate (HR) and blood pressure. As expected for a thermoregulatory organ, we found that tail blood flow increased with temperature. However, unexpectedly, we found that GSK2193874 increased tail blood flow at all temperatures, and we observed changes in HR variability. Since local TRPV4 activation causes vasodilation that would increase tail blood flow, these data suggest that increases in tail blood flow resulting from the TRPV4 antagonist may arise from a site other than the blood vessels themselves, perhaps in central cardiovascular control centres.

• Blood Pressure (BP). • Photoplethysmography (PPG). • Cuff-less and continuous blood pressure monitoring using PPG. • Machine learning models for non-invasive cuff-less blood pressure estimation. • Blood pressure estimation with recurrent neural networks. Blood pressure (BP) is a direct indicator for hypertension, therefore, continuous and non-invasive BP monitoring is essential for reducing future health complications. Most non-invasive blood pressure monitors use the oscillometric technique, which can be cumbersome and impractical. To address this problem, we explore several features extracted from the Photoplethysmogram (PPG) waveform and its first and second derivatives and employ deep learning recurrent models for non-invasive cuffless estimation for systolic and diastolic BP. In this research, three techniques have been considered including statistical and machine learning techniques for reducing the collinearity and redundancy in the input feature vector. The estimation models consist of a one bidirectional recurrent layer, followed by a series of stacked conventional recurrent layers and an attention layer. All models were evaluated on 942 subjects collected from the MIMIC II dataset. The best performing model (consists of one bidirectional layer followed by several Long Short-Term Memory layers and an attention layer) achieved a mean absolute error, and standard deviation of 4.51 ± 7.81 mmHg for systolic BP (SBP), and 2.6 ± 4.41 mmHg for diastolic BP (DBP). The results show that the deep learning model trained on features extracted from one PPG sensor yield good performance for continuous and cuffless BP monitoring. Additionally, the results fulfil the international standard for cuffless BP estimation. [ABSTRACT FROM AUTHOR]

Accurate noninvasive blood pressure (NIBP) measurement requires use of an appropriately sized cuff. We aimed to improve the perioperative allocation of NIBP cuffs in patients with Class II–III obesity. In the baseline evaluation, we measured the mid-arm circumference (MAC) of 40 patients with BMI > 35 kg/m2, documenting the corresponding cuff allocated by pre-operative nurses. The intervention consisted of the introduction of cuff allocation based on MAC measurement and augmented NIBP cuff supplies. We completed a re-evaluation and evaluation of the intervention by staff survey, using 5-point Likert scales and free text comments. At baseline, the correct cuff was allocated in 9 of 40 patients (22.5%). During the intervention, education occurred in 54 (69.2%) peri-operative nursing staff. Upon re-evaluation, the correct cuff was allocated in 30 of 40 patients (75.0%), a statistically significant improvement (χ2 = 22.1, p < 0.001). Ninety-three of 120 staff surveys were returned (78%). Eleven out of 18 preoperative staff surveyed (61.1%) felt confident measuring the arm and selecting the correct cuff. Six (33%) agreed that taking the arm measurement added a lot of extra work. Equipment shortages, accuracy concerns, and clinical workarounds were reported by staff. Our intervention increased the proportion of correct cuffs allocated, but equipment and practical issues persist with NIBP cuff selection in obese patients. [ABSTRACT FROM AUTHOR]

Objective: To investigate the difference of invasive and noninvasive blood pressure in systolic, diastolic and mean blood pressure (SBP, DBP and MAP) levels in critically ill patients. Methods: A total of 197 critically ill patients were enrolled in the intensive care unit of Peking Union Medical College Hospital in this prospective observative study. There were 113 males and 84 females with a mean age of (59±17) years. With Pearson correlation and Bland-Altman analysis, the difference and agreement of invasive and noninvasive blood pressure in SBP, DBP and MAP levels were investigated. Results: Invasive blood pressure monitoring was significantly correlated with noninvasive blood pressure (the correlation coefficients of SBP, DBP and MAP was 0.908, 0.861 and 0.888, respectively, all P <0.001). The mean bias and 95% confidence interval ( CI ) in SBP(invasive)-SBP(noninvasive), DBP(invasive)-DBP(noninvasive), MAP(invasive)-MAP(noninvasive) respectively was as following: SBP (14.5±11.9) mmHg (-8.8-37.8 mmHg); DBP (1.0±7.2) mmHg(-13.2-15.2 mmHg); MAP (10.5±8.3) mmHg (-5.9-26.8 mmHg). Moreover, there was a significant positive correlation between the bias of SBP(invasive)-SBP(noninvasive) and the value of SBP; when the SBP(invasive)≥143 mmHg was used to predict a value of bias≥20 mmHg, the sensitivity was 72.4% and specificity was 81.3%, and the area under the receiver operating characteristic curve was 0.808 (95% CI: 0.745-0.870). Conclusions: There is a good agreement between invasive and noninvasive blood pressure in critically ill patients, the bias of invasive-noninvasive blood pressure measurement is positively correlated to the value of blood pressure.