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Background: This document updates previously published Clinical Practice Guidelines for the management of patients with acute respiratory distress syndrome (ARDS), incorporating new evidence addressing the use of corticosteroids, venovenous extracorporeal membrane oxygenation, neuromuscular blocking agents, and positive end-expiratory pressure (PEEP). Methods: We summarized evidence addressing four PICO questions (patient, intervention, comparison, and outcome). A multidisciplinary panel with expertise in ARDS used the Grading of Recommendations, Assessment, Development, and Evaluation framework to develop clinical recommendations. Results: We suggest the use of: 1) corticosteroids for patients with ARDS (conditional recommendation, moderate certainty of evidence), 2) venovenous extracorporeal membrane oxygenation in selected patients with severe ARDS (conditional recommendation, low certainty of evidence), 3) neuromuscular blockers in patients with early severe ARDS (conditional recommendation, low certainty of evidence), and 4) higher PEEP without lung recruitment maneuvers as opposed to lower PEEP in patients with moderate to severe ARDS (conditional recommendation, low to moderate certainty), and 5) we recommend against using prolonged lung recruitment maneuvers in patients with moderate to severe ARDS (strong recommendation, moderate certainty). Conclusions: We provide updated evidence-based recommendations for the management of ARDS. Individual patient and illness characteristics should be factored into clinical decision making and implementation of these recommendations while additional evidence is generated from much-needed clinical trials.

Key Points: Question: What are the effects of alternative screening frequencies and spontaneous breathing trial (SBT) techniques on the time to successful extubation? Findings: In this randomized clinical trial with a factorial design that included 797 adults, there were no statistically significant differences between the main effects of screening frequency (once-daily vs more frequent screening) and SBT technique (pressure-supported vs T-piece SBTs). A significant interaction was identified between screening frequency and SBT technique. Successful extubation was achieved less rapidly with more frequent, compared with once-daily screening, when pressure-supported SBTs were used (hazard ratio, 0.7). Once-daily screening and pressure-supported SBTs (compared with T-piece SBTs) did not reduce the time to successful extubation (hazard ratio, 1.3). Meaning: Pressure-supported SBTs and more frequent protocolized screening increased the time to successful extubation. Additional work is needed to confirm the significant interaction between screening frequency and SBT technique and its effect on liberation from and discontinuation of mechanical ventilation. Importance: The optimal screening frequency and spontaneous breathing trial (SBT) technique to liberate adults from ventilators are unknown. Objective: To compare the effects of screening frequency (once-daily screening vs more frequent screening) and SBT technique (pressure-supported SBT with a pressure support level that was >0-≤8 cm H2O and a positive end-expiratory pressure [PEEP] level that was >0-≤5 cm H2O vs T-piece SBT) on the time to successful extubation. Design, Setting, and Participants: Randomized clinical trial with a 2 × 2 factorial design including critically ill adults who were receiving invasive mechanical ventilation for at least 24 hours, who were capable of initiating spontaneous breaths or triggering ventilators, and who were receiving a fractional concentration of inspired oxygen that was 70% or less and a PEEP level of 12 cm H2O or less. Recruitment was between January 2018 and February 2022 at 23 intensive care units in North America; last follow-up occurred October 18, 2022. Interventions: Participants were enrolled early to enable protocolized screening (more frequent vs once daily) to identify the earliest that patients met criteria to undergo pressure-supported or T-piece SBT lasting 30 to 120 minutes. Main Outcome and Measures: Time to successful extubation (time when unsupported, spontaneous breathing began and was sustained for ≥48 hours after extubation). Results: Of 797 patients (198 in the once-daily screening and pressure-supported SBT group, 204 in once-daily screening and T-piece SBT, 195 in more frequent screening and pressure-supported SBT, and 200 in more frequent screening and T-piece SBT), the mean age was 62.4 (SD, 18.4) years and 472 (59.2%) were men. There were no statistically significant differences by screening frequency (hazard ratio [HR], 0.88 [95% CI, 0.76-1.03]; P =.12) or by SBT technique (HR, 1.06 [95% CI, 0.91-1.23]; P =.45). The median time to successful extubation was 2.0 days (95% CI, 1.7-2.7) for once-daily screening and pressure-supported SBT, 3.1 days (95% CI, 2.7-4.8) for once-daily screening and T-piece SBT, 3.9 days (95% CI, 2.9-4.7) for more frequent screening and pressure-supported SBT, and 2.9 days (95% CI, 2.0-3.1) for more frequent screening and T-piece SBT. An unexpected interaction between screening frequency and SBT technique required pairwise contrasts that revealed more frequent screening (vs once-daily screening) and pressure-supported SBT increased the time to successful extubation (HR, 0.70 [95% CI, 0.50-0.96]; P =.02). Once-daily screening and pressure-supported SBT (vs T-piece SBT) did not reduce the time to successful extubation (HR, 1.30 [95% CI, 0.98-1.70]; P =.08). Conclusions and Relevance: Among critically ill adults who received invasive mechanical ventilation for more than 24 hours, screening frequency (once-daily vs more frequent screening) and SBT technique (pressure-supported vs T-piece SBT) did not change the time to successful extubation. However, an unexpected and statistically significant interaction was identified; protocolized more frequent screening combined with pressure-supported SBTs increased the time to first successful extubation. Trial Registration: ClinicalTrials.gov Identifiers: NCT02399267 and NCT02969226 This randomized clinical trial compares the effects of screening frequency (once-daily vs more frequent screening) and spontaneous breathing trial techniques (pressure-supported vs T-piece spontaneous breathing trial) on the time to successful extubation among critically ill adults who required invasive mechanical ventilation. [ABSTRACT FROM AUTHOR]

Background: The apnea test (AT) is an important component in the determination of brain death/death by neurologic criteria (BD/DNC) and often entails disconnecting the patient from the ventilator followed by tracheal oxygen insufflation to ensure adequate oxygenation. To rate the test as positive, most international guidelines state that a lack of spontaneous breathing must be demonstrated when the arterial partial pressure of carbon dioxide (PaCO2) ≥ 60 mm Hg. However, the loss of positive end-expiratory pressure that is associated with disconnection from the ventilator may cause rapid desaturation. This, in turn, can lead to cardiopulmonary instability (especially in patients with pulmonary impairment and diseases such as acute respiratory distress syndrome), putting patients at increased risk. Therefore, this prospective study aimed to investigate whether a modified version of the AT (mAT), in which the patient remains connected to the ventilator, is a safer yet still valid alternative. Methods: The mAT was performed in all 140 BD/DNC candidates registered between January 2019 and December 2022: after 10 min of preoxygenation, (1) positive end-expiratory pressure was increased by 2 mbar (1.5 mm Hg), (2) ventilation mode was switched to continuous positive airway pressure, and (3) apnea back-up mode was turned off (flow trigger 10 L/min). The mAT was considered positive when spontaneous breathing did not occur upon PaCO2 increase to ≥ 60 mm Hg (baseline 35–45 mm Hg). Clinical complications during/after mAT were documented. Results: The mAT was possible in 139/140 patients and had a median duration of 15 min (interquartile range 13–19 min). Severe complications were not evident. In 51 patients, the post-mAT arterial partial pressure of oxygen (PaO2) was lower than the pre-mAT PaO2, whereas it was the same or higher in 88 cases. In patients with pulmonary impairment, apneic oxygenation during the mAT improved PaO2. In 123 cases, there was a transient drop in blood pressure at the end of or after the mAT, whereas in 12 cases, the mean arterial pressure dropped below 60 mm Hg. Conclusions: The mAT is a safe and protective means of identifying patients who no longer have an intact central respiratory drive, which is a critical factor in the diagnosis of BD/DNC. Clinical trial registration DRKS, DRKS00017803, retrospectively registered 23.11.2020, https://drks.de/search/de/trial/DRKS00017803 [ABSTRACT FROM AUTHOR]

Purpose: Personalized positive end-expiratory pressure (PEEP) might foster lung and diaphragm protection in patients with acute respiratory distress syndrome (ARDS) who are undergoing pressure support ventilation (PSV). We aimed to compare the physiologic effects of personalized PEEP set according to synchronized electrical impedance tomography (EIT) and driving transpulmonary pressure (∆PL) monitoring against a classical lower PEEP/FiO2 table in intubated ARDS patients undergoing PSV. Methods: A cross-over randomized multicenter study was conducted in 30 ARDS patients with simultaneous recording of the airway, esophageal and transpulmonary pressure, together with EIT during PSV. Following a decremental PEEP trial (18 cmH2O to 4 cmH2O), PEEPEIT-∆PL was identified as the level with the smallest difference between lung overdistension and collapse. A low PEEP/FiO2 table was used to select PEEPTABLE. Each PEEP strategy was applied for 20 min, and physiologic data were collected at the end of each step. Results: The PEEP trial was well tolerated. Median PEEPEIT-∆PL was higher than PEEPTABLE (10 [8–12] vs. 8 [5–10] cmH2O; P = 0.021) and, at the individual patient level, PEEPEIT-∆PL level differed from PEEPTABLE in all patients. Overall, PEEPEIT-∆PL was associated with lower dynamic ∆PL (P < 0.001) and pressure–time product (P < 0.001), but there was variability among patients. PEEPEIT-∆PL also decreased respiratory drive and effort (P < 0.001), improved regional lung mechanics (P < 0.05) and reversed lung collapse (P = 0.007) without increasing overdistension (P = 0.695). Conclusion: Personalized PEEP selected using synchronized EIT and transpulmonary pressure monitoring could be associated with reduced dynamic lung stress and metabolic work of breathing in ARDS patients undergoing PSV. [ABSTRACT FROM AUTHOR]

Purpose: Spontaneous breathing trials (SBT) evaluate the patient's capacity to maintain inspiratory effort after extubation. SBT practices are heterogeneous and not individualised. The objective of this study was to assess which SBT best reproduces inspiratory effort after extubation in five critical illnesses. Methods: In this multicentre randomized cross-over study, adult intensive care unit patients under invasive mechanical ventilation for at least 24-h and ready for extubation, underwent three 15-min SBTs in random order: pressure support ventilation level of 7-cmH2O with positive end-expiratory pressure (PEEP) level of 0-cmH2O (PSV7PEEP0), PSV 0-cmH2O with PEEP 0-cmH2O (PSV0PEEP0) and T-piece trial. Primary outcome was the variation of pressure–time-product per minute (PTPmin) between each SBT and 20-min after extubation. Five categories of critical illnesses were selected: abdominal surgery, brain injury, chest trauma, chronic obstructive pulmonary disease (COPD) and miscellaneous. Results: Five hundred measures of effort from 100 patients were analysed. PTPmin (cmH2O s/min, median and interquartile range, IQR) was 256 (208–321) after extubation, 192 (127–281) at the end of PSV7PEEP0 (p < 0.001 in comparison to after extubation), 291 (235–347) at the end of PSV0PEEP0 and 262 (198–338) at the end of T-piece (both no different from after extubation). One method of SBT in patients with brain injury (PSV0PEEP0), two in abdominal surgery (PSV0PEEP0 and T-piece) and miscellaneous patients (PSV7PEEP0 and T-piece) and all three methods in chest trauma and COPD exacerbation patients replicated reasonably accurately the postextubation effort to breathe. Conclusion: Unassisted SBTs, namely PSV0PEEP0 and T-piece trial, are the most appropriate to replicate the postextubation effort to breathe. [ABSTRACT FROM AUTHOR]

The article comments on a study which examined difficulties of striking a balance between gaining potential benefits and minimizing the hazards associated with lung unit recruitment involving patients with acute respiratory distress syndrome (ARDS). It discusses the potential consequences of higher mean airway pressure, methods for recruitment that include raising positive end-expiratory pressure (PEEP), and the important effects of body positioning and initial baseline PEEP conditions.

BACKGROUND: Determining which patients with ARDS are most likely to benefit from lung recruitment maneuvers is challenging for physicians. The aim of this study was to assess whether the single-breath simplified decremental PEEP maneuver, which evaluates potential lung recruitment, may predict a subject's response to lung recruitment maneuvers, followed by PEEP titration. METHODS: We conducted a pilot prospective single-center cohort study with a 3-step protocol that defined sequential measurements. First, potential lung recruitment was assessed by the single-breath maneuver in the volume controlled mode. Second, the lung recruitment maneuver was performed in the pressure controlled mode, with a fixed driving pressure of 15 cm H2O and a maximum PEEP of 30 cm H2O. Third, the lung recruitment maneuver was followed by decremental PEEP titration to determine the optimal PEEP, defined as the lowest driving pressure. Responders to the lung recruitment maneuver were defined by an improvement in PaO2/FIO2 > 20% between the baseline state and the end of the PEEP titration phase. RESULTS: Forty-two subjects with moderate-to-severe ARDS were included. The mean ± SD lung recruitment was 149 ± 104 mL. A threshold lung recruitment of 195 mL (area under the receiver operator characteristic curve 0.62, 95% CI 0.43-0.80) predicted a positive response to the maximal lung recruitment maneuver. The lung recruitment maneuver, followed by PEEP titration, resulted in a modification of PEEP in 74% of the subjects. PEEP was increased in more than two thirds of the responders and decreased in almost half of the non-responders to the lung recruitment maneuver. In addition, a decrease in driving pressure and an increase in respiratory system compliance were reported in 62% and 67% of the subjects, respectively. CONCLUSIONS: The single-breath maneuver for evaluating lung recruitability predicted, with poor accuracy, the subjects who responded to the lung recruitment maneuver based on PaO2/FIO2 improvement. Nevertheless, the lung recruitment maneuver, followed by PEEP titration, improved ventilator settings and respiratory mechanics in a majority of subjects. [ABSTRACT FROM AUTHOR]

Inhalation intake of acylating pulmonary toxicants (phosgene and perfluoroisobutylene) leads to the formation of toxic pulmonary edema; the pharmacological approaches to its treatment are inefficient. Respiratory therapy is successfully used to treat the pulmonary edema of nontoxic genesis. Data on the efficiency of respiratory support during toxic pulmonary edema are limited. The aim of this study was to experimentally test the efficiency of protective artificial ventilation with maintenance of positive end-expiratory pressure in the early period of intoxication with the products of thermal degradation of fluoroplast-4. In the experimental study, it was established that early implementation of protective artificial ventilation with maintenance of end-expiratory pressure is an efficient approach for the correction of toxic pulmonary edema in rabbits in the early period of intoxication with the products of thermal degradation of fluoroplast-4, which have a toxic pulmonary effect. Respiratory support can be a promising approach for the treatment of toxic pulmonary edema caused by intoxication with acylating pulmonary toxicants. [ABSTRACT FROM AUTHOR]

Open-lung ventilation during cardiopulmonary bypass (CPB) in patients undergoing heart transplantation (HTx) is a potential strategy to mitigate postoperative acute respiratory distress syndrome (ARDS). We utilized an ovine HTx model to investigate whether open-lung ventilation during CPB reduces postoperative lung damage and complications. Eighteen sheep from an ovine HTx model were included, with ventilatory interventions randomly assigned during CPB: the OPENVENT group received low tidal volume (VT) of 3 mL/kg and positive end-expiratory pressure (PEEP) of 8 cm H20, while no ventilation was provided in the NOVENT group as per standard of care. The recipient sheep were monitored for 6 h post-surgery. The primary outcome was histological lung damage, scored at the end of the study. Secondary outcomes included pulmonary shunt, driving pressure, hemodynamics and inflammatory lung infiltration. All animals completed the study. The OPENVENT group showed significantly lower histological lung damage versus the NOVENT group (0.22 vs 0.27, p = 0.042) and lower pulmonary shunt (19.2 vs 32.1%, p = 0.001). In addition, the OPENVENT group exhibited a reduced driving pressure (9.6 cm H2O vs. 12.8 cm H2O, p = 0.039), lower neutrophil (5.25% vs 7.97%, p ≤ 0.001) and macrophage infiltrations (11.1% vs 19.6%, p < 0.001). No significant differences were observed in hemodynamic parameters. In an ovine model of HTx, open-lung ventilation during CPB significantly reduced lung histological injury and inflammatory infiltration. This highlights the value of an open-lung approach during CPB and emphasizes the need for further clinical evidence to decrease risks of lung injury in HTx patients. [ABSTRACT FROM AUTHOR]

Objective: Electrical impedance tomography (EIT) has been used to titrate positive end-expiratory pressure (PEEP). This study aims to develop a comprehensive view of the efficacy and long-term prognosis of EIT-guided PEEP compared to other conventional approaches in various clinical scenarios, including patients with acute respiratory distress syndrome (ARDS), hypoxemic acute respiratory failure (hARF) and patients undergoing surgery under general anesthesia. Methods: The literature search was conducted in PubMed, Web of Science, Embase, and Cochrane Library, from inception to July 30, 2023 (ARDS/hARF) and October 5, 2023 (surgery). The Cochrane risk of bias assessment and the methodological index for non-randomized studies were used for quality appraisal. The main outcomes were PEEP level, PaO2/FiO2 ratio, lung/respiratory system compliance (CL/Crs), driving pressure (ΔP), in-hospital mortality, and postoperative pulmonary complications (PPCs) in surgical studies. Results: Four randomized controlled trials (RCTs), one historical control study, and six before-after studies of ARDS/hARF, as well as eight surgical RCTs, were retrieved. Subgroup analysis has been carried out and analysis of before-after studies was performed separately. Diverse PEEP strategies were adopted in the included studies, such as low/high PEEP-FiO2-table of ARDS-net, pressure–volume loop, and transpulmonary pressure. In ARDS/hARF studies, the EIT strategy did not result in considerably enhanced respiratory system mechanics, including comparable PaO2/FiO2 ratios, comparable ΔP, and increased CL/Crs. As for long-term prognosis, the rough overall meta-analysis showed decreased in-hospital mortality (risk ratio RR = 1.54, 95% CI = (1.09, 2.18), P = 0.01). In patients undergoing general anesthesia surgery, the EIT group demonstrated increased PaO2/FiO2 ratio, CL/Crs, and decreased ΔP versus the fixed 4 or 5 cmH2O PEEP. In postoperative prognosis, incidence of PPCs was generally comparable between the two groups. Conclusion: The EIT-derived PEEP setting strategy might be associated with potential benefits in respiratory outcomes and prognosis in ARDS/hARF and surgical patients. Current data is insufficient to provide solid evidence. [ABSTRACT FROM AUTHOR]

Background: Progressive atelectasis regularly occurs during general anaesthesia; hence, positive end-expiratory pressure (PEEP) is often applied. Individualised PEEP titration may reduce the incidence of postoperative pulmonary complications (PPCs) and improve oxygenation as compared to fixed PEEP settings; however, evidence is lacking. Methods: This systematic review and meta-analysis was registered on PROSPERO (CRD42021282228). A systematic search in four databases (MEDLINE Via PubMed, EMBASE, CENTRAL, and Web of Science) was performed on 14 October 2021 and updated on 26 April 2024. We searched for randomised controlled trials comparing the effects of individually titrated versus fixed PEEP strategies during abdominal surgeries. The primary endpoint was the incidence of PPCs. The secondary endpoints included the PaO2/FiO2 at the end of surgery, individually set PEEP value, vasopressor requirements, and respiratory mechanics. Results: We identified 30 trials (2602 patients). The incidence of PPCs was significantly lower among patients in the individualised group (RR = 0.70, CI: 0.58–0.84). A significantly higher PaO2/FiO2 ratio was found in the individualised group as compared to controls at the end of the surgery (MD = 55.99 mmHg, 95% CI: 31.78–80.21). Individual PEEP was significantly higher as compared to conventional settings (MD = 6.27 cm H2O, CI: 4.30–8.23). Fewer patients in the control group needed vasopressor support; however, this result was non-significant. Lung-function-related outcomes showed better respiratory mechanics in the individualised group (Cstat: MD = 11.92 cm H2O 95% CI: 6.40–17.45). Conclusions: Our results show that individually titrated PEEP results in fewer PPCs and better oxygenation in patients undergoing abdominal surgery. [ABSTRACT FROM AUTHOR]

Background: Transpulmonary pressure is the effective pressure across the lung parenchyma and has been proposed as a guide for mechanical ventilation. The pleural pressure is challenging to directly measure in clinical setting and esophageal manometry using esophageal balloon catheters was suggested for estimation. However, the accuracy of using esophageal pressure to estimate pleural pressure is debated due to variability in the mechanical properties of respiratory system, esophagus and esophageal catheter. Furthermore, while a vertical pleural pressure gradient exists across lung regions, esophageal pressure balloon provides a single value, representing, at most, the pressure surrounding the esophagus. Methods: In a swine model with a preserved esophagus and a single homogenous, easily measurable intrathoracic pressure, we evaluated esophageal pressure's agreement with intrathoracic pressure at different positive end-expiratory pressure (PEEP) levels (0, 5, 10, 15 cmH2O). We assessed the improvement of measurement accuracy by correcting absolute esophageal values using a previously described technique, that accounts for the pressure generated by the esophageal wall in response to esophageal balloon inflation. The study involved five swine, wherein two different esophageal catheters were used alongside the four distinct PEEP levels. Swings, uncorrected and corrected absolute esophageal pressures (end-inspiratory, end-expiratory) were compared with their respective intrathoracic pressures. The effect of correction technique was assessed with manual incremental step inflation procedure. Results: We found that both catheters significantly overestimated absolute esophageal pressure compared to intrathoracic pressure (5.01 ± 3.32 and 6.06 ± 5.62 cmH2O at end-expiration and end-inspiration, respectively), with error increasing at higher positive end-expiratory pressure levels (end-expiration: 2.36 ± 2.03, 3.77 ± 1.37, 6.24 ± 2.51 and 7.69 ± 4.02 for each PEEP level, P < 0.0001; end-inspiration: 1.71 ± 2.10, 3.70 ± 1.73, 7.67 ± 3.62 and 11.14 ± 7.60 for each PEEP level, P = 0.0004). Applying the correction technique significantly improved agreement for absolute values (0.82 ± 1.62 and 1.86 ± 3.94 cmH2O at end-expiration and end-inspiration, respectively). Esophageal pressure swings accurately estimated intrathoracic pressure swings at low-medium intrathoracic pressures (-0.64 ± 0.62, -0.07 ± 0.53, 1.43 ± 1.51, and 3.45 ± 3.94 at PEEP 0, 5, 10 and 15 cmH2O, respectively; P = 0.0197). Conclusions: The correction technique, based on the mechanical response of esophageal wall to the balloon inflation, is fundamental for obtaining reliable estimations of absolute intrathoracic pressure values, and for ensuring its correct application in clinical setting. [ABSTRACT FROM AUTHOR]

In the intensive care unit (ICU), acute kidney injury (AKI) is the most common cause of morbidity and mortality. Hospital-acquired acute kidney injury (HAAKI) is AKI developing after 48 h. We aimed to study the development of AKI and its associated risk factors. We conducted a longitudinal observational study. Inclusion criteria were patients > 18 years of age admitted to ICU. The primary outcome was the development of AKI as defined by Kidney Disease Improving Global Outcomes (KDIGO) criteria. A total of 273 patients were included in the study. Out of 273, 44(16.11%) patients developed AKI. The mean age was 45.80(17.39) years, and 60.81% were males. The median acute physiology and chronic health evaluation (APACHE II) and sequential organ failure assessment (SOFA) scores were 12(8–18) and 5(3–7), respectively. Diabetes mellitus (23.44%) and hypertension (23.81%) were predominant comorbidities. The risk factors associated with AKI were serum chloride level, colistin, invasive ventilation, positive end-expiratory pressure (PEEP), and fluid balance. The hospital mortality was significantly higher in patients with AKI (43.18%) as compared with no AKI (14.41%). Among the secondary outcomes, 7 (15.90%) patients required renal replacement therapy (RRT) during hospitalisation. The length of ICU stay was higher in patients with AKI 8(5–13) compared to no AKI 5(3–8). A total of 16.11% developed HAAKI, and mortality was 43.18%. Post 6 months follow-up of AKI patients, mortality was 23%. Among survivors none of the patients were on RRT.Patients admitted with normal kidney function can develop AKI. Hence, careful monitoring of ICU patients is necessary. [ABSTRACT FROM AUTHOR]

Postoperative pulmonary complications (PPCs) are common in patients undergoing general anesthesia, with atelectasis being a key contributor that increases postoperative mortality and prolongs hospitalization. Our research hypothesis is that ultrasound-guided individualized PEEP titration can reduce postoperative atelectasis. This single-center randomized controlled trial recruited elderly patients for laparoscopic surgery. Patients were randomly assigned to two group: the study group (individualized PEEP groups, PEEP Ind group) and the control group (Fixed PEEP group, PEEP 5 group). All patients in these two groups received volume-controlled ventilation during general anesthesia. Patients in the study group were given ultrasound-guided PEEP, while those in the control group were given a fixed 5 cmH2O PEEP. Bedside ultrasound assessed lung ventilation. The primary outcome was the severity of atelectasis within seven days post-surgery. Eighty-nine patients scheduled for elective laparoscopic radical surgery for colorectal cancer were enrolled in our study. Lung ultrasound scores (LUSs) in the study group during postoperative seven days was significantly decreased compared with that in the control group (P < 0.05). The severity of postoperative atelectasis in the study group was significantly improved. The incidence of PPCs during postoperative 7 days in the study group was significantly less than that in the control group (48.6% vs. 77.8%; RR = 0.625; CI = 0.430–0.909; P = 0.01). In elderly patients undergoing laparoscopic radical resection, lung ultrasound-guided individualized PEEP can alleviate the severity of postoperative atelectasis. Clinical trial number and registry URL: No. ChiCTR2200062979 (https://www.chictr.org.cn). [ABSTRACT FROM AUTHOR]

Background: Nasal continuous positive airway pressure (NCPAP) is widely used for premature infants with respiratory distress syndrome (RDS). A high-flow nasal cannula (HFNC) provides positive end-expiratory pressure using high-flow oxygen; however, the variability in distending pressure is a primary concern. This study evaluated the feasibility and safety of a newly designed protocol for NCPAP weaning with cyclic HFNC use for premature infants. Methods: Premature infants with RDS using NCPAP support who were ready for weaning were enrolled. The weaning protocol used cyclic NCPAP with HFNC every 3 h for 3 days in the neonatal intensive care unit. The heart rate (HR), respiratory rate (RR), pulse oximetry (SpO2), transcutaneous carbon dioxide (PtcCO2), and cerebral tissue oxygen saturation (StO2) at the end of NCPAP with HFNC support were recorded once daily for 3 days. Results: From June 2019 to April 2021, 46 premature infants (27 male, 19 female) were enrolled. The mean gestational age and birth body weight were 28.7 ± 2.6 weeks and 1181 ± 354 g, respectively. No statistically significant differences in the HR, RR, SpO2, and cerebral StO2 during NCPAP weaning with HFNC were observed. However, the mean PtcCO2 with NCPAP was statistically significantly lower than that with HFNC (46.9 ± 6.0 mmHg vs. 47.9 ± 6.4 mmHg, P = 0.02). Conclusions: The feasibility and safety of the NCPAP weaning protocol with cyclic HFNC for premature infants are acceptable in this preliminary study. Due to the limited number of participants, further studies are required for more comprehensive analysis. Trial registration: This prospective observational case study was approved by the Human Experiment and Ethics Committee of our hospital (approval number: KMUHIRB-SV(I)-20180059; approval date: January 11, 2019). [ABSTRACT FROM AUTHOR]

At present, the strategy of setting the optimal positive end-expiratory pressure (PEEP) for mechanical ventilation still needs further clinical exploration. Electrical impedance tomography (EIT) is a newly developed technology at the end of the 20th century. It can monitor pulmonary ventilation in real time, so is extensively important to optimal PEEP setting. This review summarizes the principles of using EIT to guide PEEP setting, monitoring respiratory system compliance, spatial distribution, temporal distribution, local lung perfusion and other information published in recent years, analyzes the basic and clinical research information related to PEEP effect and its application in individualized PEEP setting. [ABSTRACT FROM AUTHOR]

Purpose: Optimal fluid management in patients with acute respiratory distress syndrome (ARDS) is challenging due to risks associated with both circulatory failure and fluid overload. The performance of dynamic indices to predict fluid responsiveness (FR) in ARDS patients is uncertain. Methods: This post hoc analysis of the HEMOPRED study compared the performance of dynamic indices in mechanically ventilated patients with shock, with and without ARDS, to predict FR, defined as an increase in aortic velocity time integral (VTI) > 10% after passive leg raising (PLR). Results: Among 540 patients, 117 (22%) had ARDS and were ventilated with a median tidal volume of 7.6 mL/kg [6.9–8.4] and a median positive end-expiratory pressure of 7 cmH2O [5–9]. FR was observed in 45 ARDS patients (39% vs 44% in non-ARDS patients, p = 0.384). Reliability of dynamic indices to predict FR remained consistent in ARDS patients, though with different thresholds. Collapsibility index of the superior vena cava (ΔSVC) showed the best predictive performance in both ARDS (area under the curve [AUC] = 0.763 [0.659–0.868]) and non-ARDS (AUC = 0.750 [0.698–0.802]) patients. A right to left ventricle end-diastolic area ratio > 0.8 or paradoxical septal motion were strongly linked to the absence of FR (> 80% specificity). FR was not associated with intensive care unit (ICU) mortality (47% vs. 46%, p = 1). However, hypovolemia, defined as an aortic VTI increase > 32% during PLR (median increase in patients with a partial SVC collapse) was independently associated with ICU mortality (odds ratio [OR] = 1.355 [1.077—1.705], p = 0.011), as well as pulse pressure variation (OR = 1.014 [1.001—1.026], p = 0.034). Conclusion: Performance of dynamic indices to predict FR appears preserved in ARDS patients, albeit with distinct thresholds. Hypovolemia, indicated by a > 32% increase in aortic VTI during PLR, rather than FR, was associated with ICU mortality in this population. [ABSTRACT FROM AUTHOR]

Why you should read this article: • To be aware that orofacial clefts are the most common facial congenital abnormalities in humans • To read a case study presenting an overview of the care provided for an infant born with a cleft palate • To recognise the vital role of children’s nurses in supporting family-centred care. Orofacial clefts are the most common facial congenital abnormalities in humans. Their management is complex due to a range of immediate and ongoing challenges. These include breathing, feeding, speech, hearing and dental issues. This article uses a case study approach to outline these challenges for a patient who was born with a cleft palate. The case is followed by a discussion of contemporary evidence-based care. The article focuses on family-centred care and multidisciplinary teamwork, and the author also details the central role of the children’s nurse. [ABSTRACT FROM AUTHOR]

Reintubation is associated with higher risk of mortality. There is no clear evidence on the best spontaneous breathing trial (SBT) method to reduce the risk of reintubation. Are different methods of conducting SBTs in critically ill patients associated with different risk of reintubation compared with T-tube? We conducted a systematic review and Bayesian network meta-analysis of randomized controlled trials investigating the effects of different SBT methods on reintubation. We surveyed PubMed, MEDLINE, CINAHL, and Cochrane Central Register of Controlled Trials databases from inception to January 26, 2024. The surface under the cumulative ranking curve (SUCRA) was used to determine the likelihood that an intervention was ranked as the best. Pairwise comparisons were also investigated by frequentist meta-analysis. Certainty of the evidence was assessed according to the Grading of Recommendations, Assessment, Development, and Evaluations approach. A total of 22 randomized controlled trials were included, for a total of 6,196 patients. The network included nine nodes, with 13 direct pairwise comparisons. About 71% of the patients were allocated to T-tube and pressure support ventilation without positive end-expiratory pressure, with 2,135 and 2,101 patients, respectively. The only intervention with a significantly lower risk of reintubation compared with T-tube was high-flow oxygen (HFO) (risk ratio, 0.23; 95% credibility interval, 0.09-0.51; moderate quality evidence). HFO was associated with the highest probability of being the best intervention for reducing the risk of reintubation (81.86%; SUCRA, 96.42), followed by CPAP (11.8%; SUCRA, 76.75). In this study, HFO SBT was associated with a lower risk of reintubation compared with other SBT methods. The results of our analysis should be considered with caution due to the low number of studies that investigated HFO SBTs and potential clinical heterogeneity related to cointerventions. Further trials should be performed to confirm the results on larger cohorts of patients and to assess specific subgroups. PROSPERO; No.: CRD42023449264; URL: https://www.crd.york.ac.uk/prospero/ [Display omitted] [ABSTRACT FROM AUTHOR]

BACKGROUND: PEEP is a cornerstone treatment for children with pediatric ARDS. Unfortunately, its titration is often performed solely by evaluating oxygen saturation, which can lead to inadequate PEEP level settings and consequent adverse effects. This study aimed to assess the impact of increasing PEEP on hemodynamics, respiratory system mechanics, and oxygenation in children with ARDS. METHODS: Children receiving mechanical ventilation and on pressure-controlled volume-guaranteed mode were prospectively assessed for inclusion. PEEP was sequentially changed to 5, 12, 10, 8 cm H2O, and again to 5 cm H2O. After 10 min at each PEEP level, hemodynamic, ventilatory, and oxygenation variables were collected. RESULTS: A total of 31 subjects were included, with median age and weight of 6 months and 6.3 kg, respectively. The main reasons for pediatric ICU admission were respiratory failure caused by acute viral bronchiolitis (45%) and community-acquired pneumonia (32%). Most subjects had mild or moderate ARDS (45% and 42%, respectively), with a median (interquartile range) oxygenation index of 8.4 (5.8-12.7). Oxygen saturation improved significantly when PEEP was increased. However, although no significant changes in blood pressure were observed, the median cardiac index at PEEP of 12 cm H2O was significantly lower than that observed at any other PEEP level (P = .001). Fourteen participants (45%) experienced a reduction in cardiac index of > 10% when PEEP was increased to 12 cm H2O. Also, the estimated oxygen delivery was significantly lower, at 12 cm H2O PEEP. Finally, respiratory system compliance significantly reduced when PEEP was increased. At a PEEP of 12 cm H2O, static compliance had a median reduction of 25% in relation to the initial assessment (PEEP of 5 cm H2O). CONCLUSIONS: Although it may improve arterial oxygen saturation, inappropriately high PEEP levels may reduce cardiac output, oxygen delivery, and respiratory system compliance in pediatric subjects with ARDS with low potential for lung recruitability. [ABSTRACT FROM AUTHOR]

Rationale: Lung-protective strategies using low Vt and moderate positive end-expiratory pressure (PEEP) are considered best practice in critical care, but interventional trials have never been conducted in patients with acute brain injuries because of concerns about carbon dioxide control and the effect of PEEP on cerebral hemodynamics. Objectives: To test the hypothesis that ventilation with lower VT and higher PEEP compared to conventional ventilation would improve clinical outcomes in patients with acute brain injury. Methods: In this multicenter, open-label, controlled clinical trial, 190 adult patients with acute brain injury were assigned to receive either a lung-protective or a conventional ventilatory strategy. The primary outcome was a composite endpoint of death, ventilator dependency, and acute respiratory distress syndrome (ARDS) at Day 28. Neurological outcome was assessed at ICU discharge by the Oxford Handicap Scale and at 6 months by the Glasgow Outcome Scale. Measurements and Main Results: The two study arms had similar characteristics at baseline. In the lung-protective and conventional strategy groups, using an intention-to-treat approach, the composite outcome at 28 days was 61.5% and 45.3% (relative risk [RR], 1.35; 95% confidence interval [CI], 1.03–1.79; P = 0.025). Mortality was 28.9% and 15.1% (RR, 1.91; 95% CI, 1.06–3.42; P = 0.02), ventilator dependency was 42.3% and 27.9% (RR, 1.52; 95% CI, 1.01–2.28; P = 0.039), and incidence of ARDS was 30.8% and 22.1% (RR, 1.39; 95% CI, 0.85–2.27; P = 0.179), respectively. The trial was stopped after enrolling 190 subjects because of termination of funding. Conclusions: In patients with acute brain injury without ARDS, a lung-protective ventilatory strategy, as compared with a conventional strategy, did not reduce mortality, percentage of patients weaned from mechanical ventilation, or incidence of ARDS and was not beneficial in terms of neurological outcomes. Because of the early termination, these preliminary results require confirmation in larger trials. Clinical trial registered with (NCT01690819). [ABSTRACT FROM AUTHOR]

(1) Background: The main objective of this research was to assess the clinical factors related to the condition of pediatric patients with congenital heart defects after they underwent intensive care unit surgery. The information was gathered from the Congenital Heart Disease Surgery Unit at the National Heart Foundation Hospital and Research Institute in Dhaka, Bangladesh. We gathered and examined data from 288 ICU patients. Patients under the age of twelve who required more than a 24-h ICU stay were selected. (2) Methods: The dependent and independent variables were chosen in advance based on expert opinion. The relationships between these pre-specified ICU parameters were determined using the Pearson correlation model and assessed through linear regression and ARIMA modeling to predict subsequent acute changes in the patients' ICU statuses. (3) Results: A statistically significant relationship (p value < 0.001) was found between CVP and BP (95% CI = 0.2113; 0.353 r = 0.2841249) and between PEEP and FiO2 (95% CI = 0.6992; 0.770 r = 0.7367744). Although the relationships between pH and PO2 were minor (95% CI = 0.161; 0.308 r = 0.2362575), they were statistically significant. The parameters considered statistically significant (p < 0.001) were chosen for forecasting. In this work, the linear regression model and the ARIMA model used the parameters BP, FiO2, and PO2 for prediction. We forecasted the patients' statuses for the next hour. It was found that the ARIMA model had a lower error rate than the linear regression model. (4) Conclusions: This study helps identify the important parameters for predicting and monitoring patients' statuses in the ICU, with the ultimate goal of providing physicians with an early warning system to anticipate deterioration in clinical and biochemical parameters. The ability to accurately forecast future patients' conditions can enable proactive, targeted interventions, potentially improving outcomes and reducing the risk of adverse events. [ABSTRACT FROM AUTHOR]

Patients with acute respiratory distress syndrome (ARDS) require periods of deep sedation and mechanical ventilation, leading to diaphragm dysfunction. Our study seeks to determine whether the combination of temporary transvenous diaphragm neurostimulation (TTDN) and mechanical ventilation changes the degree of diaphragm injury and cytokines concentration in a preclinical ARDS model. Moderate ARDS was induced in pigs using oleic acid, followed by ventilation for 12 h post-injury with volume-control at 8 mL/kg, positive end-expiratory pressure (PEEP) 5 cmH2O, respiratory rate and F I O 2 set to achieve normal arterial blood gases. Two groups received TTDN: every second breath (MV + TTDN50%, n = 6) or every breath (MV + TTDN100%, n = 6). One group received ventilation only (MV, n = 6). Full-thickness diaphragm and quadricep muscle biopsies were taken at study end. Samples were fixed and stained with hematoxylin and eosin and a point-counting technique was applied to calculate abnormal muscle area fraction. Cytokine concentrations were measured in homogenized tissue using porcine-specific enzyme-linked immunosorbent assay (ELISA) and compared with serum samples. Percentage of abnormal diaphragm tissue was different between MV [8.1% (6.0–8.8)] versus MV + TTDN50% [3.4% (2.1–4.8)], P = 0.010 and MV versus MV + TTDN100% [3.1% (2.5–4.0)], P = 0.005. Percentage of abnormal quadriceps tissue was not different between groups. Cytokine concentration patterns in diaphragm samples were different between all groups (P < 0.001) and the interaction between TTDN application and resultant cytokine concentration pattern was significant (P = 0.025). TTDN, delivered in synchrony with mechanical ventilation, mitigated diaphragm injury, as evidenced by less abnormal tissue in the diaphragm samples, in pigs with oleic acid-induced ARDS and is an exciting tool for lung and diaphragm-protective ventilation. NEW & NOTEWORTHY: This study adds to our understanding of applying transvenous diaphragm neurostimulation synchronously with mechanical ventilation by examining its effects on diaphragm muscle injury and cytokine concentration patterns in pigs with acute respiratory distress syndrome (ARDS). We observed that using this therapy for 12 h post lung injury mitigated ventilator-induced diaphragm injury and changed the pattern of cytokine concentration measured in diaphragm tissue. These findings suggest that transvenous diaphragm neurostimulation is an exciting tool for lung and diaphragm protective ventilation. [ABSTRACT FROM AUTHOR]

Background: Intraoperative driving pressure (ΔP) has an independent association with the development of postoperative pulmonary complications (PPCs) in patients receiving ventilation during general anesthesia for major surgery. Ventilation with high intraoperative positive end–expiratory pressure (PEEP) with recruitment maneuvers (RMs) that result in a low ΔP has the potential to prevent PPCs. This trial tests the hypothesis that compared to standard low PEEP without RMs, an individualized high PEEP strategy, titrated to the lowest ΔP, with RMs prevents PPCs in patients receiving intraoperative protective ventilation during anesthesia for minimally invasive abdominal surgery. Methods: "DrivinG prEssure duriNg gEneRal AnesThesia fOr minimally invasive abdominal suRgery (GENERATOR)" is an international, multicenter, two–group, patient and outcome–assessor blinded randomized clinical trial. In total, 1806 adult patients scheduled for minimally invasive abdominal surgery and with an increased risk of PPCs based on (i) the ARISCAT risk score for PPCs (≥ 26 points) and/or (ii) a combination of age > 40 years and scheduled surgery lasting > 2 h and planned to receive an intra–arterial catheter for blood pressure monitoring during the surgery will be included. Patients are assigned to either an intraoperative ventilation strategy with individualized high PEEP, titrated to the lowest ΔP, with RMs or one with a standard low PEEP of 5 cm H2O without RMs. The primary outcome is a collapsed composite endpoint of PPCs until postoperative day 5. Discussion: GENERATOR will be the first adequately powered randomized clinical trial to compare the effects of individualized high PEEP with RMs versus standard low PEEP without RMs on the occurrence of PPCs after minimally invasive abdominal surgery. The results of the GENERATOR trial will support anesthesiologists in their decisions regarding PEEP settings during minimally invasive abdominal surgery. Trial registration: GENERATOR is registered at ClinicalTrials.gov (study identifier: NCT06101511) on 26 October 2023. [ABSTRACT FROM AUTHOR]

ObjectiveMethodsResultsConclusionsParadoxical herniation (PH) is a rare but potentially life-threatening complication after decompressive craniectomy. The core treatment strategy for PH focuses on increasing intracranial pressure. Here, we present the treatment course of intractable PH in a 59-year-old patient with a traumatic acute subdural hematoma.The patient underwent two operations to evacuate intracranial hematomas followed by decompressive craniectomy within 48 h. Intractable PH was induced by persistent cerebrospinal fluid leakage due to multiple lumbar punctures. The condition was managed with conventional interventions, such as a supine position, intravenous fluid infusion, and multiple intrathecal saline injections, which have been proven to be inefficient. Owing to his unconsciousness and concurrent severe pneumonia, the patient underwent invasive mechanical ventilation with increased positive end-expiratory pressure (PEEP) to optimize oxygen delivery. PEEP was set at 10 cmH2O with the intention of facilitating alveolar recruitment.Increased PEEP unexpectedly played a role in elevating intracranial pressure and, as a result, led to the complete resolution of PH. The patient gradually recovered and resumed his daily activities.Applying invasive mechanical ventilation with increased PEEP for treating intractable PH can yield a favorable outcome. It represents a novel approach to dealing with such a rare complication. [ABSTRACT FROM AUTHOR]

Positive end-expiratory pressure results in a sustained positive intrathoracic pressure, which exerts pressure on intrathoracic vessels, resulting in cardiopulmonary interactions. This sustained positive intrathoracic pressure is known to decrease cardiac preload, and thus, decrease venous return, ultimately reducing both the stroke volume and stressed blood volume of the cardiovascular system. Currently, cardiovascular and pulmonary care are provided independently of one another. That positive end-expiratory pressure alters both stroke volume and stressed blood volume suggests both the pulmonary and cardiovascular state should be conjointly optimised. Optimising these systems in isolation may benefit one system, but have highly detrimental effects on the other. A combined cardiopulmonary model has the potential to provide a better understanding of patient specific pulmonary and cardiovascular state, as well as resulting cardiopulmonary interactions. This would enable simultaneous optimisation of all cardiovascular and pulmonary parameters. Cardiopulmonary interactions are highly patient specific and unpredictable, making accurate modelling of these interactions challenging. A previously validated cardiopulmonary model was found to have increasing errors at high positive end-expiratory pressures. A new iteration, the alpha model, was introduced to resolve this issue. This paper aims to review the alpha model against its predecessors, the previous cardiopulmonary model, and the original three chamber cardiovascular system model. All models are used to identify cardiovascular system parameters from measurements of 4 pigs during a preload reduction manoeuvre. Outputs and parameter estimations from models are compared to assess the relative performance of the alpha model against its predecessors. The novel alpha model was able to reduce model errors under high positive end-expiratory pressure, resulting in more accurate model outputs. At high positive end-expiratory pressures (20cmH2O), the alpha model had an average error of 11.24%, while the original cardiopulmonary model had a much higher error of 52.21%. Furthermore, identified outputs of the alpha model more closely matched those of the 3 chamber model than the previous cardiopulmonary model. On average, at high positive end-expiratory levels, identified model parameters from the alpha model showed a 6.21% difference to those of the 3 chamber model, while the cardiopulmonary model displayed a 39.43% difference. The alpha model proved to be more stable than the original cardiopulmonary model, making it a good candidate for model based care. However, it produced similar parameter outputs to the simpler three chamber cardiovascular model, bringing into question whether the additional complexity is justified, especially considering the low availability of clinical data in the ICU. There is a critical need for model based care to guide important procedures in ICU, such as fluid therapy. Candidate models should be continuously reviewed in order to guarantee the best possible care. [ABSTRACT FROM AUTHOR]

Introduction: Unregulated expiratory flow may contribute to ventilator-induced lung injury. The amount of energy dissipated into the lungs with tidal mechanical ventilation may be used to quantify potentially injurious ventilation. Previously reported devices for variable expiratory flow regulation (FLEX) require, either computer-controlled feedback, or an initial expiratory flow trigger. In this bench study we present a novel passive expiratory flow regulation device. Methods: The device was tested using a commercially available mechanical ventilator with a range of settings (tidal volume 420 ml and 630 ml, max. inspiratory flow rate 30 L/min and 50 L/min, respiratory rate 10 min−1, positive end-expiratory pressure 5 cmH2O), and a test lung with six different combinations of compliance and resistance settings. The effectiveness of the device was evaluated for reduction in peak expiratory flow, expiratory time, mean airway pressure, and the reduction of tidal dissipated energy (measured as the area within the airway pressure–volume loop). Results: Maximal and minimal reduction in peak expiratory flow was from 97.18 ± 0.41 L/min to 25.82 ± 0.07 L/min (p < 0.001), and from 44.11 ± 0.42 L/min to 26.30 ± 0.06 L/min, respectively. Maximal prolongation in expiratory time was recorded from 1.53 ± 0.06 s to 3.64 ± 0.21 s (p < 0.001). As a result of the extended expiration, the maximal decrease in I:E ratio was from 1:1.15 ± 0.03 to 1:2.45 ± 0.01 (p < 0.001). The greatest increase in mean airway pressure was from 10.04 ± 0.03 cmH2O to 17.33 ± 0.03 cmH2O. Dissipated energy was significantly reduced with the device under all test conditions (p < 0.001). The greatest reduction in dissipated energy was from 1.74 ± 0.00 J to 0.84 ± 0.00 J per breath. The least reduction in dissipated energy was from 0.30 ± 0.00 J to 0.16 ± 0.00 J per breath. The greatest and least percentage reduction in dissipated energy was 68% and 33%, respectively. Conclusions: The device bench tested in this study demonstrated a significant reduction in peak expiratory flow rate and dissipated energy, compared to ventilation with unregulated expiratory flow. Application of the device warrants further experimental and clinical evaluation. [ABSTRACT FROM AUTHOR]

Preclinical animal models are crucial for advancing the clinical management of acute respiratory distress syndrome (ARDS). However, there is a lack of positive findings from preclinical studies that translate into clinical practice. One possible reason for this is the inadequate optimization of positive end-expiratory pressure (PEEP) during injury development in animal models. Insufficient PEEP levels can lead to the inclusion of subjects with mild lung injury, resulting in erroneous conclusions. Therefore, it is important to prioritize PEEP optimization in preclinical ARDS models to achieve consistent and clinically relevant lung injury. A study conducted on an ovine model of ARDS found that optimizing PEEP during injury development can significantly alter injury levels and align them more accurately with clinical practice. Future preclinical studies should also incorporate clinically relevant adjunctive therapies to better replicate the complexity of ARDS in real-world scenarios. [Extracted from the article]

Background: Sigh breaths may impact outcomes in acute hypoxemic respiratory failure (AHRF) during assisted mechanical ventilation. We investigated whether sigh breaths may impact mortality in predefined subgroups of patients enrolled in the PROTECTION multicenter clinical trial according to: 1.the physiological response in oxygenation to Sigh (responders versus non-responders) and 2.the set levels of positive end-expiratory pressure (PEEP) (High vs. Low-PEEP). If mortality differed between Sigh and No Sigh, we explored physiological daily differences at 7-days. Results: Patients were randomized to pressure support ventilation (PSV) with Sigh (Sigh group) versus PSV with no sigh (No Sigh group). (1) Sighs were not associated with differences in 28-day mortality in responders to baseline sigh-test. Contrarily-in non-responders-56 patients were randomized to Sigh (55%) and 28-day mortality was lower with sighs (17%vs.36%, log-rank p = 0.031). (2) In patients with PEEP > 8cmH2O no difference in mortality was observed with sighs. With Low-PEEP, 54 patients were randomized to Sigh (48%). Mortality at 28-day was reduced in patients randomised to sighs (13%vs.31%, log-rank p = 0.021). These findings were robust to multivariable adjustments. Tidal volume, respiratory rate and ventilatory ratio decreased with Sigh as compared with No Sigh at 7-days. Ventilatory ratio was associated with mortality and successful extubation in both non-responders and Low-PEEP. Conclusions: Addition of Sigh to PSV could reduce mortality in AHRF non-responder to Sigh and exposed to Low-PEEP. Results in non-responders were not expected. Findings in the low PEEP group may indicate that insufficient PEEP was used or that Low PEEP may be used with Sigh. Sigh may reduce mortality by decreasing physiologic dead space and ventilation intensity and/or optimizing ventilation/perfusion mismatch. Clinical Trial Registration: ClinicalTrials.gov; Identifier: NCT03201263. [ABSTRACT FROM AUTHOR]

The editorial discusses the importance of optimizing oxygenation before and during tracheal intubation (TI) in critically ill patients to prevent severe complications such as hypoxaemia. Various studies have highlighted the risks associated with TI, including adverse peri-intubation events and severe hypoxia. Different methods of pre-oxygenation, such as conventional oxygen therapy (COT), non-invasive ventilation (NIV), and high-flow nasal oxygenation (HFNO), have been compared, with NIV and HFNO showing potential benefits in patients with acute hypoxaemic respiratory failure. The editorial emphasizes the need for an adaptive approach to pre-oxygenation based on patient characteristics and the severity of respiratory failure to improve patient outcomes during TI. [Extracted from the article]

This project sought to educate providers on the benefits of lung protective ventilation (LPV), implement a LPV protocol in robotic surgery, and evaluate adherence to the protocol in the adult (≥ 18 years) robotic-assisted surgery population. This project used a pre/post quality improvement design with a retrospective chart review and periodic knowledge, attitude, and practice surveys over the course of 6 months. This project retrospectively reviewed electronic medical records to assess adherence to the LPV protocol. The type of surgery; ventilator settings including positive end-expiratory pressure, FiO2, tidal volume, SpO2, ventilator mode, compliance, driving pressure and peak pressure; patient height and weight; patient body mass index; and American Society of Anesthesiologists physical status classification were collected. Analyzed results compared baseline preeducation data and data collected at 3- and 6-months postimplementation. Adherence to the LPV protocol parameters of tidal volume (P < .001), respiratory rate (P = .014), and driving pressure (P < .001) within LPV limits improved with statistical significance from pre- to postimplementation. Provider confidence and knowledge increased from pre- to posteducation (P = .049). Adherence to a LPV protocol improved with education and information tools. [ABSTRACT FROM AUTHOR]

Objective. Geometrical region of interest (ROI) selection in electrical impedance tomography (EIT) monitoring may lack sensitivity to subtle changes in ventilation distribution. Therefore, we demonstrate a new physiological method for ROI definition. This is relevant when using ROIs to compute subsequent EIT-parameters, such as the ventral-to-dorsal ratio during a positive end-expiratory pressure (PEEP) trial. Approach. Our physiological approach divides an EIT image to ensure exactly 50% tidal impedance variation in the ventral and dorsal region. To demonstrate the effects of our new method, EIT measurements during a decremental PEEP trial in 49 mechanically ventilated ICU-patients were used. We compared the center of ventilation (CoV), a robust parameter for changes in ventro-dorsal ventilation distribution, to our physiological ROI selection method and different commonly used ROI selection methods. Moreover, we determined the impact of different ROI selection methods on the PEEP level corresponding to a ventral-to-dorsal ratio closest to 1. Main results. The division line separating the ventral and dorsal ROI was closer to the CoV for our new physiological method for ROI selection compared to geometrical ROI definition. Moreover, the PEEP level corresponding to a ventral-to-dorsal ratio of 1 is strongly influenced by the chosen ROI selection method, which could have a profound clinical impact; the within-subject range of PEEP level was 6.2 cmH2O depending on the chosen ROI selection method. Significance. Our novel physiological method for ROI definition is sensitive to subtle ventilation-induced changes in regional impedance (i.e. due to (de)recruitment) during mechanical ventilation, similar to the CoV. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to compare the effect of a pressure-controlled strategy allowing non-synchronised unassisted spontaneous ventilation (PC-SV) to a conventional volume assist-control strategy (ACV) on the outcome of patients with acute respiratory distress syndrome (ARDS). Methods: Open-label randomised clinical trial in 22 intensive care units (ICU) in France. Seven hundred adults with moderate or severe ARDS (PaO2/FiO2 < 200 mmHg) were enrolled from February 2013 to October 2018. Patients were randomly assigned to PC-SV (n = 348) or ACV (n = 352) with similar objectives of tidal volume (6 mL/kg predicted body weight) and positive end-expiratory pressure (PEEP). Paralysis was stopped after 24 h and sedation adapted to favour patients' spontaneous ventilation. The primary endpoint was in-hospital death from any cause at day 60. Results: Hospital mortality [34.6% vs 33.5%, p = 0.77, risk ratio (RR) = 1.03 (95% confidence interval [CI] 0.84–1.27)], 28-day mortality, as well as the number of ventilator-free days and organ failure-free days at day 28 did not differ between PC-SV and ACV groups. Patients in the PC-SV group received significantly less sedation and neuro-muscular blocking agents than in the ACV group. A lower proportion of patients required adjunctive therapy of hypoxemia (including prone positioning) in the PC-SV group than in the ACV group [33.1% vs 41.3%, p = 0.03, RR = 0.80 (95% CI 0.66–0.98)]. The incidences of pneumothorax and refractory hypoxemia did not differ between the groups. Conclusions: A strategy based on PC-SV mode that favours spontaneous ventilation reduced the need for sedation and adjunctive therapies of hypoxemia but did not significantly reduce mortality compared to ACV with similar tidal volume and PEEP levels. [ABSTRACT FROM AUTHOR]

Background: The objective of this animal study was to evaluate the hemodynamic performance of a new centrifugal pump for extra-corporeal membrane oxygenation (ECMO) support in neonates. Methods: Six healthy swines were supported with veno-venous ECMO with the New Born ECMOLife centrifugal pump (Eurosets, Medolla, Italy) at different flow rates: 0.25, 0.5, 0.6, and 0.8 L/min; three animals were evaluated at low-flows (0.25 and 0.5 L/min) and three at high-flows (0.6 and 0.8 L/min). Each flow was maintained for 4 hours. Blood samples were collected at different time-points. Hematological and biochemical parameters and ECMO parameters [flow, revolutions per minute (RPM), drainage pressure, and the oxygenator pressure drop] were evaluated. Results: The increase of the pump flow from 0.25 to 0.5 L/min or from 0.6 to 0.8 L/min required significantly higher RPM and produced significantly higher pump pressures [from 0.25 to 0.5 L/min: 1470 (1253–1569) versus 2652 (2589–2750) RPM and 40 (26–57) versus 125 (113–139) mmHg, respectively; p <.0001 for both - from 0.60 to 0.8 L/min: 1950 (1901–2271) versus 2428 (2400–2518) RPM and 66 (62–86) versus 106 (101–113) mmHg, respectively; p <.0001 for both]. Median drainage pressure significantly decreased from −18 (−22; −16) mmHg to −55 (−63; −48) mmHg when the pump flow was increased from 0.25 to 0.5 L/min (p <.0001). When pump flow increased from 0.6 to 0.8 L/min, drainage pressure decreased from −32 (−39; −24) mmHg to −50 (−52; −43) mmHg, (p <.0001). Compared to pre-ECMO values, the median levels of lactate dehydrogenase, d-dimer, hematocrit, and platelet count decreased after ECMO start at all flow rates, probably due to hemodilution. Plasma-free hemoglobin, instead, showed a modest increase compared to pre-ECMO values during all experiments at different pump flow rates. However, these changes were not clinically relevant. Conclusions: In this animal study, the "New Born ECMOLife" centrifugal pump showed good hemodynamic performance. Long-term studies are needed to evaluate biocompatibility of this new ECMO pump. [ABSTRACT FROM AUTHOR]

ARDS is a heterogeneous condition with two subphenotypes identified by different methodologies. Our group similarly identified two ARDS subphenotypes using nine routinely available clinical variables. However, whether these are associated with differential response to treatment has yet to be explored. Are there differential responses to positive end-expiratory pressure (PEEP) strategies on 28-day mortality according to subphenotypes in adult patients with ARDS? We evaluated data from two prior ARDS trials (Higher vs Lower Positive End-Expiratory Pressures in Patients With the ARDS [ALVEOLI] and the Alveolar Recruitment in ARDS Trial [ART]) that compared different PEEP strategies. We classified patients into one of two subphenotypes as described previously. We assessed the differential effect of PEEP with a Bayesian hierarchical logistic model for the primary outcome of 28-day mortality. We analyzed data from 1,559 patients with ARDS. Compared with lower PEEP, a higher PEEP strategy resulted in higher 28-day mortality in patients with subphenotype A disease in the ALVEOLI study (OR, 1.61; 95% credible interval [CrI], 0.90-2.94) and ART (OR, 1.73; 95% CrI, 1.01-2.98), with a probability of harm resulting from higher PEEP in this subphenotype of 94.3% and 97.7% in the ALVEOLI and ART studies, respectively. Higher PEEP was not associated with mortality in patients with subphenotype B disease in each trial (OR, 0.95 [95% CrI, 0.51-1.73] and 1.00 [95% CrI, 0.63-1.55], respectively), with probability of benefit of 56.4% and 50.7% in the ALVEOLI and ART studies, respectively. These effects were not modified by Pa o 2 to F io 2 ratio, driving pressure, or the severity of illness for the cohorts. We found evidence of differential response to PEEP strategies across two ARDS subphenotypes, suggesting possible harm with a higher PEEP strategy in one subphenotype. These observations may assist with predictive enrichment in future clinical trials. [Display omitted] [ABSTRACT FROM AUTHOR]

OBJECTIVES: Despite the recommendation for lung-protective mechanical ventilation (LPMV) in pediatric acute respiratory distress syndrome (PARDS), there is a lack of robust supporting data and variable adherence in clinical practice. This study evaluates the impact of an LPMV protocol vs. standard care and adherence to LPMV elements on mortality. We hypothesized that LPMV strategies deployed as a pragmatic protocol reduces mortality in PARDS. DESIGN: Multicenter prospective before-and-after comparison design study. SETTING: Twenty-one PICUs. PATIENTS: Patients fulfilled the Pediatric Acute Lung Injury Consensus Conference 2015 definition of PARDS and were on invasive mechanical ventilation. INTERVENTIONS: The LPMV protocol included a limit on peak inspiratory pressure (PIP), delta/driving pressure (DP), tidal volume, positive end-expiratory pressure (PEEP) to FIO2 combinations of the low PEEP acute respiratory distress syndrome network table, permissive hypercarbia, and conservative oxygen targets. MEASUREMENTS AND MAIN RESULTS: There were 285 of 693 (41[middle dot]1%) and 408 of 693 (58[middle dot]9%) patients treated with and without the LPMV protocol, respectively. Median age and oxygenation index was 1.5 years (0.4-5.3 yr) and 10.9 years (7.0-18.6 yr), respectively. There was no difference in 60-day mortality between LPMV and non-LPMV protocol groups (65/285 [22.8%] vs. 115/406 [28.3%]; p = 0.104). However, total adherence score did improve in the LPMV compared to non-LPMV group (57.1 [40.0-66.7] vs. 47.6 [31.0-58.3]; p < 0[middle dot]001). After adjusting for confounders, adherence to LPMV strategies (adjusted hazard ratio, 0.98; 95% CI, 0.97-0.99; p = 0.004) but not the LPMV protocol itself was associated with a reduced risk of 60-day mortality. Adherence to PIP, DP, and PEEP/FIO2 combinations were associated with reduced mortality. CONCLUSIONS: Adherence to LPMV elements over the first week of PARDS was associated with reduced mortality. Future work is needed to improve implementation of LPMV in order to improve adherence. [ABSTRACT FROM AUTHOR]

The document is a collection of abstracts from the Fifth Regional Neurocritical Care Meeting in the Middle East and Africa, held in conjunction with the 20th Emirates Critical Care Conference. The abstracts were reviewed by a panel of experts using criteria such as importance, originality, and quality. The abstracts cover a range of topics, including the time to cardiac arrest after removal of organ support in brain dead patients, the association between glycated albumin and clinical outcomes in acute ischemic stroke patients, the evaluation of topical lidocaine patches in mechanically ventilated patients, the outcomes and resources used by do not resuscitate (DNR) patients in the ICU, and a randomized controlled trial comparing the effectiveness of uridine monophosphate with vitamin B12 and folic acid versus gabapentin in reducing neuropathic pain in diabetic patients. [Extracted from the article]

Background: Hypoxemia is the main modifiable factor preventing lungs from being transplanted from organ donors after brain death. One major contributor to impaired oxygenation in patients with brain injury is atelectasis. Apnea testing, an integral component of brain death declaration, promotes atelectasis and can worsen hypoxemia. In this study, we tested whether performing a recruitment maneuver (RM) after apnea testing could mitigate hypoxemia and atelectasis. Methods: During the study period, an RM (positive end-expiratory pressure of 15 cm H2O for 15 s then 30 cm H2O for 30 s) was performed immediately after apnea testing. We measured partial pressure of oxygen, arterial (PaO2) before and after RM. The primary outcomes were oxygenation (PaO2 to fraction of inspired oxygen [FiO2] ratio) and the severity of radiographic atelectasis (proportion of lung without aeration on computed tomography scans after brain death, quantified using an image analysis algorithm) in those who became organ donors. Outcomes in RM patients were compared with control patients undergoing apnea testing without RM in the previous 2 years. Results: Recruitment maneuver was performed in 54 patients after apnea testing, with a median immediate increase in PaO2 of 63 mm Hg (interquartile range 0–109, p = 0.07). Eighteen RM cases resulted in hypotension, but none were life-threatening. Of this cohort, 37 patients became organ donors, compared with 37 donors who had apnea testing without RM. The PaO2:FiO2 ratio was higher in the RM group (355 ± 129 vs. 288 ± 127, p = 0.03), and fewer had hypoxemia (PaO2:FiO2 ratio < 300 mm Hg, 22% vs. 57%; p = 0.04) at the start of donor management. The RM group showed less radiographic atelectasis (median 6% vs. 13%, p = 0.045). Although there was no difference in lungs transplanted (35% vs. 24%, p = 0.44), both better oxygenation and less atelectasis were associated with a higher likelihood of lungs being transplanted. Conclusions: Recruitment maneuver after apnea testing reduces hypoxemia and atelectasis in organ donors after brain death. This effect may translate into more lungs being transplanted. [ABSTRACT FROM AUTHOR]

The article shares insight on the application of positive end-expiratory pressure (PEEP) during mechanical ventilation in patients with acute respiratory distress syndrome (ARDS). It discusses developments in adjunct clinical tools and noninvasive imaging techniques that may help shift PEEP titration such as the use of esophageal pressure measurements to approximate transpulmonary pressures and the use of electrical impedance tomography to explore the impact of PEEP on ventilation distribution.

BACKGROUND: High-flow tracheal oxygen (HFTO) is being used as supportive therapy during weaning in tracheostomized patients difficult to wean from invasive mechanical ventilation. There is, however, no clinical evidence for such a strategy. Therefore, we conducted a systematic review to summarize studies evaluating the physiologic effects of HFTO during tracheostomy-facilitated weaning and to identify potential areas for future research in this field. METHODS: Observational and interventional studies on critically ill subjects weaning from mechanical ventilation via tracheostomy published until December 22, 2022, were eligible. Studies on high-flow oxygen, only in children, non-human models or animals, on clinical outcome only, abstracts without full-text availability, case reports, and reviews were excluded. Main outcomes were end-expiratory lung volume (EELV) and tidal volume using electrical impedance tomography, respiratory effort assessed by esophageal manometry, work of breathing and neuroventilatory drive as assessed by electrical activity of the diaphragm (EAdi) signal, airway pressure (Paw), oxygenation (... or ...), breathing frequency, tidal volume, and .... RESULTS: In total, 1,327 references were identified, of which 5 were included. In all studies, HFTO was administered with flow 50 L/min and compared to conventional O2 therapy in a crossover design. The total average duration of invasive ventilation at time of measurements ranged from 11-27 d. In two studies, ... and mean Paw were higher with HFTO. EELV, tidal volumes, esophageal pressure swings, and EAdi were similar during high-flow tracheal oxygen and conventional O2 therapy. CONCLUSIONS: The main physiological effect of HFTO as compared to conventional O2 therapy in tracheostomized subjects weaning from mechanical ventilation was improved oxygenation that is probably flow-dependent. Respiratory effort, lung aeration, neuroventilatory drive, and ventilation were similar for HFTO and conventional O2 therapy. Future studies on HFTO should be performed early in the weaning process and should evaluate its effect on sputum clearance and patient-centered outcomes like dyspnea. [ABSTRACT FROM AUTHOR]

BACKGROUND: The first aim of this study was to evaluate the capacity of electrical impedance tomography (EIT) to identify the effect of PEEP on regional ventilation distribution and the regional risk of collapse, overdistention, hypoventilation, and pendelluft in mechanically ventilated patients. The second aim was to evaluate the feasibility of EIT for estimating airway opening pressure (AOP). METHODS: The EIT signal was recorded both during baseline cyclic ventilation and slow insufflation for one breath for 9 subjects with moderate-to-severe ARDS. From these data, the AOP and volumes insufflated to lung regions with or without the risk of either collapse, overdistention, hypoventilation, or pendelluft were assessed at 3 PEEP levels (5, 10, and 15 cm H2O). PEEP levels were compared by Friedman analysis of variance and the AOP measured by EIT evaluated using an F-test and the Bland and Altman method. RESULTS: The volume for which there was no specific risk significantly decreased at the highest PEEP from 55 ± 31% tidal volume (VT) at PEEP = or 82 ± 18% VT at PEEP 10 to 10 ± 30% VT at PEEP 15 (P = .038 between PEEP 5 vs PEEP 15; P = .01 between PEEP 10 vs PEEP 15). The volume associated with overdistention significantly increased with increasing PEEP, whereas that associated with atelec-trauma significantly decreased. Pendelluft significantly decreased with increasing PEEP: VT of 8.9 ± 18.6%, 3.6 ± 7.0%, and 3.2 ± 7.1% for PEEP 5, PEEP 10, and PEEP 15, respectively. The center of ventilation tended to increase in the dependent direction with higher PEEP. The AOPs assessed by EIT and from the pressure-volume curve were in good agreement (bias 0.48 cm H2O). CONCLUSIONS: Our results suggest that EIT could aid clinicians in making personalized and reasoned choices in setting the PEEP for subjects with ARDS. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to assess the effect of mechanical ventilation based on predicted body weight (PBW) and driving pressure (DP) as directed in patients without acute respiratory distress syndrome (ARDS). Design: Experimental, single-blind design with pretest-posttest control group design to assess the effect of using PBW and DP as a guide in regulating the amount of tidal volume and airway pressure in mechanically ventilated patients without ARDS. Setting: We conducted this study in the Intensive Care Unit (ICU) at Dr. Wahidin Sudirohusodo General Hospital, Makassar, from November 2023 to March 2024. Patients and participants: Patients with respiratory failure who were admitted to the ICU of Dr. Wahidin Sudirohusodo General Hospital, Makassar. Intervention: Patients in the PBW group were given a tidal volume setting of 8 ml/kg PBW, adjusted to the lowest positive end-expiratory pressure (PEEP) with the largest lung compliance target, while the DP group did the same thing and adjusted the tidal volume regarding the driving pressure target. The oxygen partial pressure (pO2), carbon dioxide partial pressure (pCO2), oxygen partial pressure to fractional inspired oxygen ratio (P/F ratio), mechanical power, and ventilatory ratio were assessed at the first hour and 24th hour. Measurement and results: Thirty-two patients were divided into two groups, 16 patients each, recruited from November 2023 to March 2024. There was a significant difference in the P/F ratio in the DP group compared to the PBW group after 24 hours (p<0.001 vs p=0.190). Similarly, pCO2 after 24 hours significantly differed between the DP group (p=0.001) and the PBW group (p=0.658). Regarding mechanical power, the two groups had no significant difference (10.92±2.51 vs 11.68±1.21 Joules/min, p=0.284). The PBW group had a wider range of mechanical power values (range 8.4 J/min) than the DP group (range 4.6 J/min), suggesting the DP group had more consistent mechanical power magnitude. Conclusion: Mechanical ventilation guided by DP can improve oxygenation and ventilation outcomes. Even though both the PBW and DP methods resulted in similar mechanical power levels, the DP-guided approach provided more stable and predictable mechanical power values. This stability can benefit patient management in the ICU, as it suggests a reduced risk of lung injury and potentially better overall outcomes for patients receiving mechanical ventilation. [ABSTRACT FROM AUTHOR]

Rationale: A U-shaped relationship should exist between lung volume and pulmonary vascular resistance (PVR), with minimal PVR at FRC. Thus, positive end-expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS) should increase PVR if it induces significant lung distension compared with recruitment. However, this has never been proved in patients. Objectives: To study the effects of PEEP on PVR according to lung recruitability, evaluated by the recruitment-to-inflation (R/I) ratio. Methods: In patients with ARDS, we measured hemodynamic (pulmonary artery catheter), echocardiographic, and ventilatory variables (including esophageal pressure) at both low PEEP and higher PEEP by 10 cm H2O. Preload responsiveness was assessed by the passive leg-raising test at high PEEP. Measurements and Main Results: We enrolled 23 patients, including 10 low recruiters (R/I <0.5) and 13 high recruiters (R/I ⩾0.5). Raising PEEP from 4 (2–5) to 14 (12–15) cm H2O increased PVR in low recruiters (from 160 [120–297] to 243 [166–380] dyn·s/cm5; P < 0.01), whereas PVR was unchanged in high recruiters (from 224 [185–289] to 235 [168–300] dyn·s/cm5; P = 0.55). Right-to-left ventricular end-diastolic area ratio simultaneously increased in low recruiters (from 0.54 [0.50–0.59] to 0.64 [0.56–0.70]; P < 0.01) while remaining stable in high recruiters (from 0.70 [0.65–0.79] to 0.68 [0.58–0.80]; P = 0.48). Raising PEEP decreased cardiac index only in preload responsive patients. Conclusions: PEEP increases PVR only when it induces significant lung distension compared with recruitment according to the R/I ratio. Tailoring PEEP on this recruitability index should mitigate its hemodynamic effects. [ABSTRACT FROM AUTHOR]

Purpose: Growing evidence shows the complex interaction between lung and kidney in critically ill patients. The renal resistive index (RRI) is a bedside measurement of the resistance of the renal blood flow and it is correlated with kidney injury. The positive end-expiratory pressure (PEEP) level could affect the resistance of renal blood flow, so we assumed that RRI could help to monitoring the changes in renal hemodynamics at different PEEP levels. Our hypothesis was that the RRI at ICU admission could predict the risk of acute kidney injury in mechanical ventilated critically ill patients. Methods: We performed a prospective study including 92 patients requiring mechanical ventilation for ≥ 48 h. A RRI ≥ 0.70, was deemed as pathological. RRI was measured within 24 h from ICU admission while applying 5,10 and 15 cmH2O of PEEP in random order (PEEP trial). Results: Overall, RRI increased from 0.62 ± 0.09 at PEEP 5 to 0.66 ± 0.09 at PEEP 15 (p < 0.001). The mean RRI value during the PEEP trial was able to predict the occurrence of AKI with AUROC = 0.834 [95%CI 0.742–0.927]. Patients exhibiting a RRI ≥ 0.70 were 17/92(18%) at PEEP 5, 28/92(30%) at PEEP 10, 38/92(41%) at PEEP 15, respectively. Thirty-eight patients (41%) exhibited RRI ≥ 0.70 at least once during the PEEP trial. In these patients, AKI occurred in 55% of the cases, versus 13% remaining patients, p < 0.001. Conclusions: RRI seems able to predict the risk of AKI in mechanical ventilated patients; further, RRI values are influenced by the PEEP level applied. Trial registration: Clinical gov NCT03969914 Registered 31 May 2019. [ABSTRACT FROM AUTHOR]

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Introduction: Anesthesia management, surgical techniques, and patient variables all affect postoperative recovery. After anesthesia and surgery, the Quality of Recovery-15 questionnaire is used to evaluate the quality of recovery. Pneumoperitoneum can affect respiratory mechanics and raise the risk of atelectasis during laparoscopic cholecystectomy. Protective mechanical ventilation techniques, such as recruitment maneuvers and positive end-expiratory pressure, may improve postoperative recovery by increasing oxygenation and lowering pulmonary problems. This study investigates the effects of different ventilation strategies during laparoscopic cholecystectomy on oxygenation, respiratory mechanics, hemodynamics, and postoperative recovery quality. Materials and Methods: Two groups of sixty laparoscopic cholecystectomy patients were randomly assigned. Control (Group C) receiving 5 cmH2O positive end-expiratory pressure and Recruitment (Group R) receiving the same positive endexpiratory pressure plus recruitment maneuvers. Hemodynamic parameters, blood gas v alues, and Quality of Recovery-15 scores were recorded and analyzed using statistical methods. Results: The Recruitment group showed significantly higher partial pressure of oxygen (PO2) measurements at all intraoperative time points T1 (5 minutes after insufflation), T2 (5 minutes after desufflation), and T3 (1 hour postoperatively) compared to the Control group. The Recruitment group exhibited a higher peak airway pressure (Ppeak) at both T1 and T2. At fifteen minutes postoperatively, the mean arterial pressure in the recruitment group was considerably lower. Better postoperative recovery was shown by the Recruitment group's considerably higher Quality of Recovery-15 scores. Conclusion: Recruitment maneuvers during laparoscopic cholecystectomy improve oxyg enation and postoperative recovery quality, as evidenced by higher Quality of Recovery-15 scores. These findings suggest the potential benefits of integrating recruitment maneuvers into perioperative care plans to enhance patient outcomes. [ABSTRACT FROM AUTHOR]

Abstract Background Patients with brain damage often require mechanical ventilation. Although lung-protective ventilation is recommended, the application of increased positive end-expiratory pressure (PEEP) has been associated with elevated intracranial pressure (ICP) due to altered cerebral venous return. This study investigates the effects of flow-controlled ventilation (FCV) using negative end-expiratory pressures (NEEP), on cerebral hemodynamics in a swine model of intracranial hypertension. Methods A model of intracranial hypertension involving bilateral trepan bolt holes was performed in 14 pigs. Pressure-controlled volume-guaranteed ventilation (PCV-VG) with PEEP and FCV using PEEP and then NEEP were applied. Intracranial pressure and oxygenation, as well as systemic hemodynamics and gas exchange parameters, were continuously monitored. Data were collected at baseline and at varying PEEP levels for both PCV-VG and FCV ventilation modalities. Following this, FCV ventilation and NEEP levels of -3, -6 and -9 cmH2O were applied. Results ICP remained stable with low PEEP levels, but significantly decreased with NEEP. Lower ICP following NEEP improved cerebral perfusion pressure and cerebral tissue oxygenation (p

Abstract Objective Electrical impedance tomography (EIT) has been used to titrate positive end-expiratory pressure (PEEP). This study aims to develop a comprehensive view of the efficacy and long-term prognosis of EIT-guided PEEP compared to other conventional approaches in various clinical scenarios, including patients with acute respiratory distress syndrome (ARDS), hypoxemic acute respiratory failure (hARF) and patients undergoing surgery under general anesthesia. Methods The literature search was conducted in PubMed, Web of Science, Embase, and Cochrane Library, from inception to July 30, 2023 (ARDS/hARF) and October 5, 2023 (surgery). The Cochrane risk of bias assessment and the methodological index for non-randomized studies were used for quality appraisal. The main outcomes were PEEP level, PaO2/FiO2 ratio, lung/respiratory system compliance (CL/Crs), driving pressure (ΔP), in-hospital mortality, and postoperative pulmonary complications (PPCs) in surgical studies. Results Four randomized controlled trials (RCTs), one historical control study, and six before-after studies of ARDS/hARF, as well as eight surgical RCTs, were retrieved. Subgroup analysis has been carried out and analysis of before-after studies was performed separately. Diverse PEEP strategies were adopted in the included studies, such as low/high PEEP-FiO2-table of ARDS-net, pressure–volume loop, and transpulmonary pressure. In ARDS/hARF studies, the EIT strategy did not result in considerably enhanced respiratory system mechanics, including comparable PaO2/FiO2 ratios, comparable ΔP, and increased CL/Crs. As for long-term prognosis, the rough overall meta-analysis showed decreased in-hospital mortality (risk ratio RR = 1.54, 95% CI = (1.09, 2.18), P = 0.01). In patients undergoing general anesthesia surgery, the EIT group demonstrated increased PaO2/FiO2 ratio, CL/Crs, and decreased ΔP versus the fixed 4 or 5 cmH2O PEEP. In postoperative prognosis, incidence of PPCs was generally comparable between the two groups. Conclusion The EIT-derived PEEP setting strategy might be associated with potential benefits in respiratory outcomes and prognosis in ARDS/hARF and surgical patients. Current data is insufficient to provide solid evidence.

At present, the strategy of setting the optimal positive end-expiratory pressure (PEEP) for mechanical ventilation still needs further clinical exploration. Electrical impedance tomography (EIT) is a newly developed technology at the end of the 20th century. It can monitor pulmonary ventilation in real time, so is extensively important to optimal PEEP setting. This review summarizes the principles of using EIT to guide PEEP setting, monitoring respiratory system compliance, spatial distribution, temporal distribution, local lung perfusion and other information published in recent years, analyzes the basic and clinical research information related to PEEP effect and its application in individualized PEEP setting.