Critical Care Bulletin: October 2024

 

Predicting outcomes in patients with exacerbation of COPD requiring mechanical ventilation

Annals of Intensive Care volume 14, Article number: 159, Published: 20 October 2024

Background

Acute exacerbations of COPD (AECOPD) are common and significantly contribute to mortality in patients with COPD. Prognostic scores can assist clinicians in making tailored decisions to manage AECOPD. In the current study, we therefore aimed to evaluate the performance of the Noninvasive Ventilation Outcomes (NIVO) score, originally designed to assess in-ICU mortality, in predicting 1 year mortality and NIV failure in AECOPD.

Methods

This retrospective study analyzed data from patients hospitalized for AECOPD requiring mechanical ventilation between January 1st, 2018, and December 31st, 2022. Mortality was assessed at the end of ICU stay and 1 year after admission, while NIV failure was defined as intubation or death without intubation.

Results

Among 302 ICU admissions of COPD patients, 190 patients with AECOPD requiring mechanical ventilation were included. Of these, 44 (23%) died in the ICU, 62 out of 184 (34%) failed NIV, and 78 (41%) died within 1 year of admission. Patients who died in ICU or experienced NIV failure had more severe COPD and more impaired blood gas parameters at admission. The NIVO score demonstrated an AUC of 0.68 in predicting 1-year mortality and an AUC of 0.85 in predicting NIV failure. A NIVO score over 7 was associated with higher 1-year mortality and NIV failure (HR of 4.4 [1.8–10.9] and 41.6 [5.6–307.9], respectively).

Conclusion

Beyond predicting in-ICU mortality, the NIVO-score is a reliable tool in predicting 1-year mortality and NIV failure in AECOPD.

 

Oxygen therapy and noninvasive respiratory supports in acute hypoxemic respiratory failure: a narrative review

Annals of Intensive Care volume 14, Article number: 158 (2024)

Background

This narrative review was written by an expert panel to the members of the jury to help in the development of clinical practice guidelines on oxygen therapy.

Results

According to the expert panel, acute hypoxemic respiratory failure was defined as PaO₂ < 60 mm Hg or SpO₂ < 90% on room air, or PaO₂/FiO₂ ≤ 300 mm Hg. Supplemental oxygen should be administered according to the monitoring of SpO₂, with the aim at maintaining SpO₂ above 92% and below 98%. Noninvasive respiratory supports are generally reserved for the most hypoxemic patients with the aim of relieving dyspnea. High-flow nasal cannula oxygen (HFNC) seems superior to conventional oxygen therapy (COT) as a means of avoiding intubation and may therefore be should probably be used as a first-line noninvasive respiratory support in patients requiring more than 6 L/min of oxygen or PaO₂/FiO₂ ≤ 200 mm Hg and a respiratory rate above 25 breaths/minute or clinical signs of respiratory distress, but with no benefits on mortality. Continuous positive airway pressure (CPAP) cannot currently be recommended as a first-line noninvasive respiratory support, since its beneficial effects on intubation remain uncertain. Despite older studies favoring noninvasive ventilation (NIV) over COT, recent clinical trials fail to show beneficial effects with NIV compared to HFNC. Therefore, there is no evidence to support the use of NIV or CPAP as first-line treatment if HFNC is available. Clinical trials do not support the hypothesis that noninvasive respiratory supports may lead to late intubation. The potential benefits of awake prone positioning on the risk of intubation in patients with COVID-19 cannot be extrapolated to patients with another etiology.

Conclusions

Whereas oxygen supplementation should be initiated for patients with acute hypoxemic respiratory failure defined as PaO₂ below 60 mm Hg or SpO₂ < 90% on room air, HFNC should be the first-line noninvasive respiratory support in patients with PaO₂/FiO₂ ≤ 200 mm Hg with increased respiratory rate. Further studies are needed to assess the potential benefits of CPAP, NIV through a helmet and awake prone position in patients with acute hypoxemic respiratory failure not related to COVID-19.

 

Risk Stratification and Management of Acute Respiratory Failure in Patients With Neuromuscular Disease

Critical Care Medicine 52(11):p 1781-1789, November 2024.

OBJECTIVES: 

Guillain-Barré syndrome (GBS) and myasthenia gravis (MG) are the most common causes of acute neuromuscular respiratory failure resulting in ICU admission. This synthetic narrative review summarizes the evidence for the prediction and management of acute neuromuscular respiratory failure due to GBS and MG.

DATA SOURCES: 

We searched PubMed for relevant literature and reviewed bibliographies of included articles for additional relevant studies.

STUDY SELECTION: 

English-language publications were reviewed.

DATA EXTRACTION: 

Data regarding study methodology, patient population, evaluation metrics, respiratory interventions, and clinical outcomes were qualitatively assessed.

DATA SYNTHESIS: 

No single tool has sufficient sensitivity and specificity for the prediction of acute neuromuscular respiratory failure requiring mechanical ventilation. Multimodal assessment, integrating history, examination maneuvers (single breath count, neck flexion strength, bulbar weakness, and paradoxical breathing) and pulmonary function testing are ideal for risk stratification. The Erasmus GBS Respiratory Insufficiency Score is a validated tool useful for GBS. Noninvasive ventilation can be effective in MG but may not be safe in early GBS. Airway management considerations are similar across both conditions, but dysautonomia in GBS requires specific attention. Extubation failure is common in MG, and early tracheostomy may be beneficial for MG. Prolonged ventilatory support is common, and good functional outcomes may occur even when prolonged ventilation is required.

CONCLUSIONS: 

Multimodal assessments integrating several bedside indicators of bulbar and respiratory muscle function can aid in evidence-based risk stratification for respiratory failure among those with neuromuscular disease. Serial evaluations may help establish a patient’s trajectory and to determine timing of respiratory intervention.

 

Direct Laryngoscopy Versus Video Laryngoscopy for Intubation in Critically Ill Patients: A Systematic Review, Meta-Analysis, and Trial Sequential Analysis of Randomized Trials*

Critical Care Medicine 52(11):p 1674-1685, November 2024.

OBJECTIVES: 

Given the uncertainty regarding the optimal approach to laryngoscopy for the intubation of critically ill adult patients, we conducted a systematic review and meta-analysis to compare video laryngoscopy (VL) vs. direct laryngoscopy (DL) for intubation in emergency department and ICU patients.

DATA SOURCES: 

We searched MEDLINE, PubMed, Embase, Cochrane Library, and unpublished sources, from inception to February 27, 2024.

STUDY SELECTION: 

We included randomized controlled trials (RCTs) of critically ill adult patients randomized to VL compared with DL for endotracheal intubation.

DATA EXTRACTION: 

Reviewers screened abstracts, full texts, and extracted data independently and in duplicate. We pooled data using a random-effects model, assessed risk of bias using the modified Cochrane tool and certainty of evidence using the Grading Recommendations Assessment, Development, and Evaluation approach. We pre-registered the protocol on PROSPERO (CRD42023469945).

DATA SYNTHESIS: 

We included 20 RCTs (n = 4569 patients). Compared with DL, VL probably increases first pass success (FPS) (relative risk [RR], 1.13; 95% CI, 1.06–1.21; moderate certainty) and probably decreases esophageal intubations (RR, 0.47; 95% CI, 0.27–0.82; moderate certainty). VL may result in fewer aspiration events (RR, 0.74; 95% CI, 0.51–1.09; low certainty) and dental injuries (RR, 0.46; 95% CI, 0.19–1.11; low certainty) and may have no effect on mortality (RR, 0.97; 95% CI, 0.88–1.07; low certainty) compared with DL.

CONCLUSIONS: 

In critically ill adult patients undergoing intubation, the use of VL, compared with DL, probably leads to higher rates of FPS and probably decreases esophageal intubations. VL may result in fewer dental injuries as well as aspiration events compared with DL with no effect on mortality.

Hypothermia versus normothermia in patients with cardiac arrest and shockable rhythm: a secondary analysis of the TTM-2 study

Critical Care volume 28, Article number: 335, Published: 15 October 2024

Background

The aim of this study was to assess whether hypothermia increased survival and improved functional outcome when compared with normothermia in out-of-hospital cardiac arrest (OHCA) patients with similar characteristics than in previous randomized studies showing benefits for hypothermia.

Methods

Post hoc analysis of a pragmatic, multicenter, randomized clinical trial (TTM-2, NCT02908308). In this analysis, the subset of patients included in the trial who had similar characteristics to patients included in one previous randomized trial and randomized to hypothermia at 33 °C or normothermia (i.e. target < 37.8 °C) were considered. The primary outcome was survival at 6 months; secondary outcomes included favorable functional outcome at 6 months, defined as a modified Rankin scale of 0–3. Time-to-death and the occurrence of adverse events were also reported.

Results

From a total of 1891 included in the TTM-2 study, 600 (31.7%) were included in the analysis, 294 in the hypothermia and 306 in the normothermia group. At 6 months, 207 of the 294 patients (70.4%) in the hypothermia group and 220 of the 306 patients (71.8%) in the normothermia group had survived (relative risk with hypothermia, 0.96; 95% confidence interval [CI], 0.81 to 1.15; P = 0.71). Also, 198 of the 294 (67.3%) in the hypothermia group and 202 of the 306 (66.0%) in the normothermia group had a favorable functional outcome (relative risk with hypothermia, 1.03; 95% CI, 0.87 to 1.23; P = 0.79). There was a significant increase in the occurrence of arrythmias in the hypothermia group (62/294, 21.2%) when compared to the normothermia group (43/306, 14.1%—OR 1.49, 95% CI 1.05–2.14; p = 0.026).

Conclusions

In this study, hypothermia at 33˚C did not improve survival or functional outcome in a subset of patients with similar cardiac arrest characteristics to patients in whom benefit from hypothermia was shown in prior studies.

 Biomarkers in cardiogenic shock: old pals, new friends

Annals of Intensive Care volume 14, Article number: 157, Published: 16 October 2024

Abstract

In cardiogenic shock, biomarkers should ideally help make the diagnosis, choose the right therapeutic options and monitor the patient in addition to clinical and echocardiographic indices. Among “old” biomarkers that have been used for decades, lactate detects, quantifies, and follows anaerobic metabolism, despite its lack of specificity. Renal and liver biomarkers are indispensable for detecting the effect of shock on organ function and are highly predictive of poor outcomes. Direct biomarkers of cardiac damage such as cardiac troponins, B-type natriuretic and N-terminal pro-B-type natriuretic peptides have a good prognostic value, but they lack specificity to detect a cardiogenic cause of shock, as many factors influence their plasma concentrations in critically ill patients. Among the biomarkers that have been more recently described, dipeptidyl peptidase-3 is one of the most interesting. In addition to its prognostic value, it could represent a therapeutic target in cardiogenic shock in the future as a specific antibody inhibits its activity. Adrenomedullin is a small peptide hormone secreted by various tissues, including vascular smooth muscle cells and endothelium, particularly under pathological conditions. It has a vasodilator effect and has prognostic value during cardiogenic shock. An antibody inhibits its activity and so adrenomedullin could represent a therapeutic target in cardiogenic shock. An increasing number of inflammatory biomarkers are also of proven prognostic value in cardiogenic shock, reflecting the inflammatory reaction associated with the syndrome. Some of them are combined to form prognostic proteomic scores. Alongside clinical variables, biomarkers can be used to establish biological “signatures” characteristic of the pathophysiological pathways involved in cardiogenic shock. This helps describe patient subphenotypes, which could in the future be used in clinical trials to define patient populations responding specifically to a treatment.

 

 

Impact of sleep disturbances on outcomes in intensive care units

Critical Care volume 28, Article number: 331, Published: 09 October 2024

Background

Sleep deprivation is common in intensive care units (ICUs) and may alter respiratory performance. Few studies have assessed the role of sleep disturbances on outcomes in critically ill patients.

Objectives

We hypothesized that sleep disturbances may be associated with poor outcomes in ICUs.

Methods

Post-hoc analysis pooling three observational studies assessing sleep by complete polysomnography in 131 conscious and non-sedated patients included at different times of their ICU stay. Sleep was assessed early in a group of patients admitted for acute respiratory failure while breathing spontaneously (n = 34), or under mechanical ventilation in patients with weaning difficulties (n = 45), or immediately after extubation (n = 52). Patients admitted for acute respiratory failure who required intubation, those under mechanical ventilation who had prolonged weaning, and those who required reintubation after extubation were considered as having poor clinical outcomes. Durations of deep sleep, rapid eye movement (REM) sleep, and atypical sleep were compared according to the timing of polysomnography and the clinical outcomes.

Results

Whereas deep sleep remained preserved in patients admitted for acute respiratory failure, it was markedly reduced under mechanical ventilation and after extubation (p < 0.01). Atypical sleep was significantly more frequent in patients under mechanical ventilation than in those breathing spontaneously (p < 0.01). REM sleep was uncommon at any time of their ICU stay. Patients with complete disappearance of REM sleep (50% of patients) were more likely to have poor clinical outcomes than those with persistent REM sleep (24% vs. 9%, p = 0.03).

Conclusion

Complete disappearance of REM sleep was significantly associated with poor clinical outcomes in critically ill patients.

 

Blood trauma in veno-venous extracorporeal membrane oxygenation: low pump pressures and low circuit resistance matter

Critical Care volume 28, Article number: 330, Published: 08 October 2024

Background

Veno-venous extracorporeal membrane oxygenation (VV ECMO) has become standard of care in patients with the most severe forms of acute respiratory distress syndrome. However, hemolysis and bleeding are one of the most frequent side effects, affecting mortality. Despite the widespread use of VV ECMO, current protocols lack detailed, in-vivo data-based recommendations for safe ECMO pump operating conditions. This study aims to comprehensively analyze the impact of VV ECMO pump operating conditions on hemolysis by combining in-silico modeling and clinical data analysis.

Methods

We combined data from 580 patients treated with VV ECMO in conjunction with numerical predictions of hemolysis using computational fluid dynamics and reduced order modeling of the Rotaflow (Getinge) and DP3 (Xenios) pumps. Blood trauma parameters across 94,779 pump operating points were associated with numerical predictions of shear induced hemolysis.

Results

Minimal hemolysis was observed at low pump pressures and low circuit resistance across all flow rates, whereas high pump pressures and circuit resistance consistently precipitated substantial hemolysis, irrespective of flow rate. However, the lower the flow rate, the more pronounced the influence of circuit resistance on hemolysis became. Numerical models validated against clinical data demonstrated a strong association (Spearman’s r = 0.8) between simulated and observed hemolysis, irrespective of the pump type.

Conclusions

Integrating in-silico predictions with clinical data provided a novel approach in understanding and potentially reducing blood trauma in VV ECMO. This study further demonstrated that a key factor in lowering side effects of ECMO support is the maintenance of low circuit resistance, including oxygenators with the lowest possible resistance, the shortest feasible circuit tubing, and cannulae with an optimal diameter.

 

A narrative review on antimicrobial dosing in adult critically ill patients on extracorporeal membrane oxygenation

Critical Care volume 28, Article number: 326, Published: 04 October 2024

Abstract

The optimal dosing strategy of antimicrobial agents in critically ill patients receiving extracorporeal membrane oxygenation (ECMO) is unknown. We conducted comprehensive review of existing literature on effect of ECMO on pharmacokinetics and pharmacodynamics of antimicrobials, including antibacterials, antifungals, and antivirals that are commonly used in critically ill patients. We aim to provide practical guidance to clinicians on empiric dosing strategy for these patients. Finally, we discuss importance of therapeutic drug monitoring, limitations of current literature, and future research directions.

 

European Society of Intensive Care Medicine guidelines on end of life and palliative care in the intensive care unit

Intensive Care Med (2024). Published 03 October 2024

Abstract

The European Society of Intensive Care Medicine (ESICM) has developed evidence-based recommendations and expert opinions about end-of-life (EoL) and palliative care for critically ill adults to optimize patient-centered care, improving outcomes of relatives, and supporting intensive care unit (ICU) staff in delivering compassionate and effective EoL and palliative care. An international multi-disciplinary panel of clinical experts, a methodologist, and representatives of patients and families examined key domains, including variability across countries, decision-making, palliative-care integration, communication, family-centered care, and conflict management. Eight evidence-based recommendations (6 of low level of evidence and 2 of high level of evidence) and 19 expert opinions were presented. EoL legislation and the importance of respecting the autonomy and preferences of patients were given close attention. Differences in EoL care depending on country income and healthcare provision were considered. Structured EoL decision-making strategies are recommended to improve outcomes of patients and relatives, as well as staff satisfaction and mental health. Early integration of palliative care and the use of standardized tools for symptom assessment are suggested for patients at high risk of dying. Communication training for ICU staff and printed communication aids for families are advocated to improve outcomes and satisfaction. Methods for enhancing family-centeredness of care include structured family conferences and culturally sensitive interventions. Conflict-management protocols and strategies to prevent burnout among healthcare professionals are also considered. The work done to develop these guidelines highlights many areas requiring further research.

 

The Impact of Point-of-Care Ultrasound-Guided Resuscitation on Clinical Outcomes in Patients With Shock: A Systematic Review and Meta-Analysis

Critical Care Medicine 52(11):p 1661-1673, November 2024.

OBJECTIVE: 

To determine the impact of point-of-care ultrasound (POCUS)-guided resuscitation on clinical outcomes in adult patients with shock.

DATA SOURCE: 

We searched MEDLINE, Embase, and unpublished sources from inception to December 2023.

STUDY SELECTION: 

We included randomized controlled trials (RCTs) that examined the use of POCUS to guide resuscitation in patients with shock.

DATA EXTRACTION: 

We collected data regarding study and patient characteristics, POCUS protocol, control group interventions, and outcomes.

DATA SYNTHESIS: 

We identified 18 eligible RCTs. POCUS slightly influences physicians’ plans for IV fluid (IVF) and vasoactive medication prescription (moderate certainty), but results in little to no changes in the administration of IVF (low to high certainty) or inotropes (high certainty). POCUS may result in no change in the number of CT scans performed (low certainty) but probably reduces the number of diagnostic echocardiograms performed (moderate certainty). POCUS-guided resuscitation probably reduces 28-day mortality (relative risk [RR] 0.88; 95% CI, 0.78–0.99), the duration of vasoactive medication (mean difference –0.73 d; 95% CI, –1.16 to –0.30), and the need for renal replacement therapy (RRT) (RR 0.80; 95% CI, 0.63–1.02) (low to moderate certainty evidence), and lactate clearance (high certainty evidence). POCUS-guided resuscitation may results in little to no difference in ICU or hospital admissions, ICU and hospital length of stay, and the need for mechanical ventilation (MV) (low to moderate certainty evidence). There is an uncertain effect on the risk of acute kidney injury and the duration of MV or RRT (very low certainty evidence).

CONCLUSIONS: 

POCUS-guided resuscitation in shock may yield important patient and health system benefits. Due to lack of sufficient evidence, we were unable to explore how the thresholds of operator competency, frequency, and timing of POCUS scans impact patient outcomes.

 

Relationship between SARS-CoV-2 infection and ICU-acquired candidemia in critically ill medical patients: a multicenter prospective cohort study

Critical Care volume 28, Article number: 320, Published: 27 September 2024

Background

While SARS-CoV2 infection has been shown to be a significant risk-factor for several secondary bacterial, viral and Aspergillus infections, its impact on intensive care unit (ICU)-acquired candidemia (ICAC) remains poorly explored.

Method

Using the REA-REZO network (French surveillance network of ICU-acquired infections), we included all adult patients hospitalized for a medical reason of admission in participating ICUs for at least 48 h from January 2020 to January 2023. To account for confounders, a non-parsimonious propensity score matching was performed. Rates of ICAC according to SARS-CoV2 status were compared in matched patients. Factors associated with ICAC in COVID-19 patients were also assessed using a Fine-Gray model.

Results

A total of 55,268 patients hospitalized at least 48 h for a medical reason in 101 ICUs were included along the study period. Of those, 13,472 were tested positive for a SARS-CoV2 infection while 284 patients developed an ICAC. ICAC rate was higher in COVID-19 patients in both the overall population and the matched patients’ cohort (0.8% (107/13,472) versus 0.4% (173/41,796); p < 0.001 and 0.8% (93/12,241) versus 0.5% (57/12,241); p = 0.004, respectively). ICAC incidence rate was also higher in those patients (incidence rate 0.51 per 1000 patients-days in COVID-19 patients versus 0.32 per 1000 patients-days; incidence rate ratio: 1.58 [95% CI:1.08–2.35]; p = 0.018). Finally, patients with ICAC had a higher ICU mortality rate (49.6% versus 20.2%; p < 0.001).

Conclusion

In this large multicenter cohort of ICU patients, although remaining low, the rate of ICAC was higher among COVID-19 patients.

 

Impact of airway closure and lung collapse on inhaled nitric oxide effect in acute lung injury: an experimental study

Annals of Intensive Care  volume 14, Article number: 149, Published: 23 September 2024

Background

Efficacy of inhaled therapy such as Nitric Oxide (iNO) during mechanical ventilation may depend on airway patency. We hypothesized that airway closure and lung collapse, countered by positive end-expiratory pressure (PEEP), influence iNO efficacy. This could support the role of an adequate PEEP titration for inhalation therapy. The main aim of this study was to assess the effect of iNO with PEEP set above or below the airway opening pressure (AOP) generated by airway closure, on hemodynamics and gas exchange in swine models of acute respiratory distress syndrome. Fourteen pigs randomly underwent either bilateral or asymmetrical two-hit model of lung injury. Airway closure and lung collapse were measured with electrical impedance tomography as well as ventilation/perfusion ratio (V/Q). After AOP detection, the effect of iNO (10ppm) was studied with PEEP set randomly above or below regional AOP. Respiratory mechanics, hemodynamics, and gas-exchange were recorded.

Results

All pigs presented airway closure (AOP > 0.5cmH₂O) after injury. In bilateral injury, iNO was associated with an improved mean pulmonary pressure from 49 ± 8 to 42 ± 7mmHg; (p = 0.003), and ventilation/perfusion matching, caused by a reduction in pixels with low V/Q and shunt from 16%[IQR:13–19] to 9%[IQR:4–12] (p = 0.03) only at PEEP set above AOP. iNO had no effect on hemodynamics or gas exchange for PEEP below AOP (low V/Q 25%[IQR:16–30] to 23%[IQR:14–27]; p = 0.68). In asymmetrical injury, iNO improved pulmonary hemodynamics and ventilation/perfusion matching independently from the PEEP set. iNO was associated with improved oxygenation in all cases.

Conclusions

In an animal model of bilateral lung injury, PEEP level relative to AOP markedly influences iNO efficacy on pulmonary hemodynamics and ventilation/perfusion match, independently of oxygenation.

Critical Care Bulletin - September 2024

 

Innate immune response in acute critical illness: a narrative review

Annals of Intensive Care volume 14, Article number: 137 (2024) Published: 04 September 2024

Background

Activation of innate immunity is a first line of host defense during acute critical illness (ACI) that aims to contain injury and avoid tissue damages. Aberrant activation of innate immunity may also participate in the occurrence of organ failures during critical illness. This review aims to provide a narrative overview of recent advances in the field of innate immunity in critical illness, and to consider future potential therapeutic strategies.

Main text

Understanding the underlying biological concepts supporting therapeutic strategies modulating immune response is essential in decision-making. We will develop the multiple facets of innate immune response, especially its cellular aspects, and its interaction with other defense mechanisms. We will first describe the pathophysiological mechanisms of initiation of innate immune response and its implication during ACI. We will then develop the amplification of innate immunity mediated by multiple effectors. Our review will mainly focus on myeloid and lymphoid cellular effectors, the major actors involved in innate immune-mediated organ failure. We will third discuss the interaction and integration of innate immune response in a global view of host defense, thus considering interaction with non-immune cells through immunothrombosis, immunometabolism and long-term reprogramming via trained immunity. The last part of this review will focus on the specificities of the immune response in children and the older population.

Conclusions

Recent understanding of the innate immune response integrates immunity in a highly dynamic global vision of host response. A better knowledge of the implicated mechanisms and their tissue-compartmentalization allows to characterize the individual immune profile, and one day eventually, to develop individualized bench-to-bedside immunomodulation approaches as an adjuvant resuscitation strategy.

 

Assessment of fluid responsiveness using pulse pressure variation, stroke volume variation, plethysmographic variability index, central venous pressure, and inferior vena cava variation in patients undergoing mechanical ventilation: a systematic review and meta-analysis

Critical Care volume 28, Article number: 289 (2024) Published: 31 August 2024

Importance

Maneuvers assessing fluid responsiveness before an intravascular volume expansion may limit useless fluid administration, which in turn may improve outcomes.

Objective

To describe maneuvers for assessing fluid responsiveness in mechanically ventilated patients.

Registration

The protocol was registered at PROSPERO: CRD42019146781.

Information sources and search

PubMed, EMBASE, CINAHL, SCOPUS, and Web of Science were search from inception to 08/08/2023.

Study selection and data collection

Prospective and intervention studies were selected.

Statistical analysis

Data for each maneuver were reported individually and data from the five most employed maneuvers were aggregated. A traditional and a Bayesian meta-analysis approach were performed.

Results

A total of 69 studies, encompassing 3185 fluid challenges and 2711 patients were analyzed. The prevalence of fluid responsiveness was 49.9%. Pulse pressure variation (PPV) was studied in 40 studies, mean threshold with 95% confidence intervals (95% CI) = 11.5 (10.5–12.4)%, and area under the receiver operating characteristics curve (AUC) with 95% CI was 0.87 (0.84–0.90). Stroke volume variation (SVV) was studied in 24 studies, mean threshold with 95% CI = 12.1 (10.9–13.3)%, and AUC with 95% CI was 0.87 (0.84–0.91). The plethysmographic variability index (PVI) was studied in 17 studies, mean threshold = 13.8 (12.3–15.3)%, and AUC was 0.88 (0.82–0.94). Central venous pressure (CVP) was studied in 12 studies, mean threshold with 95% CI = 9.0 (7.7–10.1) mmHg, and AUC with 95% CI was 0.77 (0.69–0.87). Inferior vena cava variation (∆IVC) was studied in 8 studies, mean threshold = 15.4 (13.3–17.6)%, and AUC with 95% CI was 0.83 (0.78–0.89).

Conclusions

Fluid responsiveness can be reliably assessed in adult patients under mechanical ventilation. Among the five maneuvers compared in predicting fluid responsiveness, PPV, SVV, and PVI were superior to CVP and ∆IVC. However, there is no data supporting any of the above mentioned as being the best maneuver. Additionally, other well-established tests, such as the passive leg raising test, end-expiratory occlusion test, and tidal volume challenge, are also reliable.

 

Factors associated with cancer treatment resumption after ICU stay in patients with solid tumors

Annals of Intensive Care volume 14, Article number: 135 (2024) Published: 31 August 2024

Background

Post-intensive care syndrome could be responsible for inability to receive proper cancer treatment after ICU stay in patients with solid tumors (ST). Our purpose was to determine the factors associated with cancer treatment resumption and the impact of cancer treatment on the outcome of patients with ST after ICU stay.

Methods

We conducted a retrospective study including all patients with ST admitted to the ICU between 2014 and 2019 in a French University-affiliated Hospital.

Results

A total of 219 patients were included. Median SAPS II at ICU admission was 44.0 [IQR 32.8, 66.3]. Among the 136 patients who survived the ICU stay, 81 (59.6%) received cancer treatment after ICU discharge. There was an important increase in patients with poor performance status (PS) of 3 or 4 after ICU stay (16.2% at admission vs. 44.5% of patients who survived), with significant PS decline following the ICU stay (median difference − 1.5, 95% confidence interval [-1.5-1.0], p < 0.001). The difference between the PS after and before ICU stay (delta PS) was independently associated with inability to receive cancer treatment (Odds ratio OR 0.34, 95%CI 0.18–0.56, p value < 0.001) and with 1-year mortality in patients who survived at ICU discharge (Hazard ratio HR 1.76, 95%CI 1.34–2.31, p value < 0.001). PS before ICU stay (OR 3.73, 95%IC 2.01–7.82, p value < 0.001) and length of stay (OR 1.23, 95%CI 1.06–1.49, p value 0.018) were independently associated with poor PS after ICU stay. Survival rates at ICU discharge, at 1 and 3 years were 62.3% (n = 136), 27.3% (n = 59) and 17.1% (n = 37), respectively. The median survival for patients who resumed cancer treatment after ICU stay was 771 days (95%CI 376–1058), compared to 29 days (95%CI 15–49) for those who did not resume treatment (p < 0.001).

Conclusion

Delta PS, before and after ICU stay, stands out as a critical determinant of cancer treatment resumption and survival after ICU stay. Multidisciplinary intervention to improve the general condition of these patients, in ICU and after ICU stay, may improve access to cancer treatment and long-term survival.

 

The ventilator of the future: key principles and unmet needs

Critical Care volume 28, Article number: 284 (2024) Published: 29 August 2024

Abstract

Persistent shortcomings of invasive positive pressure ventilation make it less than an ideal intervention. Over the course of more than seven decades, clinical experience and scientific investigation have helped define its range of hazards and limitations. Apart from compromised airway clearance and lower airway contamination imposed by endotracheal intubation, the primary hazards inherent to positive pressure ventilation may be considered in three broad categories: hemodynamic impairment, potential for ventilation-induced lung injury, and impairment of the respiratory muscle pump. To optimize care delivery, it is crucial for monitoring and machine outputs to integrate information with the potential to impact the underlying requirements of the patient and/or responses of the cardiopulmonary system to ventilatory interventions. Trending analysis, timely interventions, and closer communication with the caregiver would limit adverse clinical trajectories. Judging from the rapid progress of recent years, we are encouraged to think that insights from physiologic research and emerging technological capability may eventually address important aspects of current deficiencies.

 

How are Long-Covid, Post-Sepsis-Syndrome and Post-Intensive-Care-Syndrome related? A conceptional approach based on the current research literature

Critical Care volume 28, Article number: 283 (2024)  Published: 29 August 2024

Abstract

Long-Covid (LC), Post-Sepsis-Syndrome (PSS) and Post-Intensive-Care-Syndrome (PICS) show remarkable overlaps in their clinical presentation. Nevertheless, it is unclear if they are distinct syndromes, which may co-occur in the same patient, or if they are three different labels to describe similar symptoms, assigned on the basis on patient history and professional perspective of the treating physician. Therefore, we reviewed the current literature on the relation between LC, PSS and PICS. To date, the three syndromes cannot reliably be distinguished due similarities in clinical presentation as they share the cognitive, psychological and physical impairments with only different probabilities of occurrence and a heterogeneity in individual expression. The diagnosis is furthermore hindered by a lack of specific diagnostic tools. It can be concluded that survivors after COVID-19 sepsis likely have more frequent and more severe consequences than patients with milder COVID-19 courses, and that are some COVID-19-specific sequelae, e.g. an increased risk for venous thromboembolism in the 30 days after the acute disease, which occur less often after sepsis of other causes. Patients may profit from leveraging synergies from PICS, PSS and LC treatment as well as from experiences gained from infection-associated chronic conditions in general. Disentangling molecular pathomechanisms may enable future targeted therapies that go beyond symptomatic treatment.

 

Development of a biomarker prediction model for post-trauma multiple organ failure/dysfunction syndrome based on the blood transcriptome

Annals of Intensive Care volume 14, Article number: 134 (2024) Published: 28 August 2024

Background

Multiple organ failure/dysfunction syndrome (MOF/MODS) is a major cause of mortality and morbidity among severe trauma patients. Current clinical practices entail monitoring physiological measurements and applying clinical score systems to diagnose its onset. Instead, we aimed to develop an early prediction model for MOF outcome evaluated soon after traumatic injury by performing machine learning analysis of genome-wide transcriptome data from blood samples drawn within 24 h of traumatic injury. We then compared its performance to baseline injury severity scores and detection of infections.

Methods

Buffy coat transcriptome and linked clinical datasets from blunt trauma patients from the Inflammation and the Host Response to Injury Study (“Glue Grant”) multi-center cohort were used. According to the inclusion/exclusion criteria, 141 adult (age ≥ 16 years old) blunt trauma patients (excluding penetrating) with early buffy coat (≤ 24 h since trauma injury) samples were analyzed, with 58 MOF-cases and 83 non-cases. We applied the Least Absolute Shrinkage and Selection Operator (LASSO) and eXtreme Gradient Boosting (XGBoost) algorithms to select features and develop models for MOF early outcome prediction.

Results

The LASSO model included 18 transcripts (AUROC [95% CI]: 0.938 [0.890–0.987] (training) and 0.833 [0.699–0.967] (test)), and the XGBoost model included 41 transcripts (0.999 [0.997–1.000] (training) and 0.907 [0.816–0.998] (test)). There were 16 overlapping transcripts comparing the two panels (0.935 [0.884–0.985] (training) and 0.836 [0.703–0.968] (test)). The biomarker models notably outperformed models based on injury severity scores and sex, which we found to be significantly associated with MOF (APACHEII + sex—0.649 [0.537–0.762] (training) and 0.493 [0.301–0.685] (test); ISS + sex—0.630 [0.516–0.744] (training) and 0.482 [0.293–0.670] (test); NISS + sex—0.651 [0.540–0.763] (training) and 0.525 [0.335–0.714] (test)).

Conclusions

The accurate assessment of MOF from blood samples immediately after trauma is expected to aid in improving clinical decision-making and may contribute to reduced morbidity, mortality and healthcare costs. Moreover, understanding the molecular mechanisms involving the transcripts identified as important for MOF prediction may eventually aid in developing novel interventions.

 

Role of age as eligibility criterion for ECMO in patients with ARDS: meta-regression analysis

Critical Care volume 28, Article number: 278 (2024) Published: 27 August 2024

Background

Age as an eligibility criterion for V-V ECMO is widely debated and varies among healthcare institutions. We examined how age relates to mortality in patients undergoing V-V ECMO for ARDS.

Methods

Systematic review and meta-regression of clinical studies published between 2015 and June 2024. Studies involving at least 6 ARDS patients treated with V-V ECMO, with specific data on ICU and/or hospital mortality and patient age were included. The search strategy was executed in PubMed, limited to English-language. COVID-19 and non-COVID-19 populations were analyzed separately. Meta-regressions of mortality outcomes on age were performed using gender, BMI, SAPS II, APACHE II, Charlson comorbidity index or SOFA as covariates.

Results

In non-COVID ARDS, the meta-regression of 173 studies with 56,257 participants showed a significant positive association between mean age and ICU/hospital mortality. In COVID-19 ARDS, a significant relationship between mean age and ICU mortality, but not hospital mortality, was found in 103 studies with 21,255 participants. Sensitivity analyses confirmed these findings, highlighting a linear relationship between age and mortality in both groups. For each additional year of mean age, ICU mortality increased by 1.2% in non-COVID ARDS and 1.9% in COVID ARDS.

Conclusions

The relationship between age and ICU mortality is linear and shows no inflection point. Consequently, no age cut-off can be recommended for determining patient eligibility for V-V ECMO.

 

Derivation and external validation of predictive models for invasive mechanical ventilation in intensive care unit patients with COVID-19

Annals of Intensive Care volume 14, Article number: 129 (2024) Published: 21 August 2024

Background

This study aimed to develop prognostic models for predicting the need for invasive mechanical ventilation (IMV) in intensive care unit (ICU) patients with COVID-19 and compare their performance with the Respiratory rate-OXygenation (ROX) index.

Methods

A retrospective cohort study was conducted using data collected between March 2020 and August 2021 at three hospitals in Rio de Janeiro, Brazil. ICU patients aged 18 years and older with a diagnosis of COVID-19 were screened. The exclusion criteria were patients who received IMV within the first 24 h of ICU admission, pregnancy, clinical decision for minimal end-of-life care and missing primary outcome data. Clinical and laboratory variables were collected. Multiple logistic regression analysis was performed to select predictor variables. Models were based on the lowest Akaike Information Criteria (AIC) and lowest AIC with significant p values. Assessment of predictive performance was done for discrimination and calibration. Areas under the curves (AUC)s were compared using DeLong’s algorithm. Models were validated externally using an international database.

Results

Of 656 patients screened, 346 patients were included; 155 required IMV (44.8%), 191 did not (55.2%), and 207 patients were male (59.8%). According to the lowest AIC, arterial hypertension, diabetes mellitus, obesity, Sequential Organ Failure Assessment (SOFA) score, heart rate, respiratory rate, peripheral oxygen saturation (SpO2), temperature, respiratory effort signals, and leukocytes were identified as predictors of IMV at hospital admission. According to AIC with significant p values, SOFA score, SpO2, and respiratory effort signals were the best predictors of IMV; odds ratios (95% confidence interval): 1.46 (1.07–2.05), 0.81 (0.72–0.90), 9.13 (3.29–28.67), respectively. The ROX index at admission was lower in the IMV group than in the non-IMV group (7.3 [5.2–9.8] versus 9.6 [6.8–12.9], p < 0.001, respectively). In the external validation population, the area under the curve (AUC) of the ROX index was 0.683 (accuracy 63%), the AIC model showed an AUC of 0.703 (accuracy 69%), and the lowest AIC model with significant p values had an AUC of 0.725 (accuracy 79%).

Conclusions

In the development population of ICU patients with COVID-19, SOFA score, SpO2, and respiratory effort signals predicted the need for IMV better than the ROX index. In the external validation population, although the AUCs did not differ significantly, the accuracy was higher when using SOFA score, SpO2, and respiratory effort signals compared to the ROX index. This suggests that these variables may be more useful in predicting the need for IMV in ICU patients with COVID-19.

 

Long-term effects of flexible visitation in the intensive care unit on family members’ mental health: 12-month results from a randomized clinical trial

Intensive Care Medicine, Published: 22 August 2024

Purpose

The aim of this study was to assess the effects of flexible intensive care unit (ICU) visitation on the 1-year prevalence of post-traumatic stress, anxiety and depression symptoms among family members of critically ill patients.

Methods

This is a long-term outcome analysis of a cluster-crossover randomized clinical trial that evaluated a flexible visitation model in the ICU (12 h/day) compared to a restrictive visitation model (median 1.5 h/day) in 36 Brazilian ICUs. In this analysis, family members were assessed 12 months after patient discharge from the ICU for the following outcomes: post-traumatic stress symptoms measured by the Impact Event Scale-6 and anxiety and depression symptoms measured by the Hospital Anxiety and Depression Scale.

Results

A total of 519 family members were analyzed (288 in the flexible visitation group and 231 in the restrictive visitation group). Three-hundred sixty-nine (71.1%) were women, and the mean age was 46.6 years. Compared to family members in the restrictive visitation group, family members in the flexible visitation group had a significantly lower prevalence of post-traumatic stress symptoms (21% vs. 30.5%; adjusted prevalence ratio [aPR], 0.91; 95% confidence interval [CI] 0.85–0.98; p = 0.01). The prevalence of anxiety (28.9% vs. 33.2%; aPR 0.93; 95% CI 0.72–1.21; p = 0.59) and depression symptoms (19.2% vs. 25%; aPR, 0.78; 95% CI 0.60–1.02; p = 0.07) did not differ significantly between the groups.

Conclusion

Flexible ICU visitation, compared to the restrictive visitation, was associated with a significant reduction in the 1-year prevalence of post-traumatic stress symptoms in family members.

 

Early reapplication of prone position during venovenous ECMO for acute respiratory distress syndrome: a prospective observational study and propensity-matched analysis

by Rui Wang, Xiao Tang, Xuyan Li, Ying Li, Yalan Liu, Ting Li, Yu Zhao, Li Wang, Haichao Li, Meng Li, Hu Li, Zhaohui Tong and Bing Sun 

Annals of Intensive Care volume 14, Article number: 127 (2024) Published: 20 August 2024

Background

A combination of prone positioning (PP) and venovenous extracorporeal membrane oxygenation (VV-ECMO) is safe, feasible, and associated with potentially improved survival for severe acute respiratory distress syndrome (ARDS). However, whether ARDS patients, especially non-COVID-19 patients, placed in PP before VV-ECMO should continue PP after a VV-ECMO connection is unknown. This study aimed to test the hypothesis that early use of PP during VV-ECMO could increase the proportion of patients successfully weaned from ECMO support in severe ARDS patients who received PP before ECMO.

Methods

In this prospective observational study, patients with severe ARDS who were treated with VV-ECMO were divided into two groups: the prone group and the supine group, based on whether early PP was combined with VV-ECMO. The proportion of patients successfully weaned from VV-ECMO and 60-day mortality were analyzed before and after propensity score matching.

Results

A total of 165 patients were enrolled, 50 in the prone and 115 in the supine group. Thirty-two (64%) and 61 (53%) patients were successfully weaned from ECMO in the prone and the supine groups, respectively. The proportion of patients successfully weaned from VV-ECMO in the prone group tended to be higher, albeit not statistically significant. During PP, there was a significant increase in partial pressure of arterial oxygen (PaO2) without a change in ventilator or ECMO settings. Tidal impedance shifted significantly to the dorsal region, and lung ultrasound scores significantly decreased in the anterior and posterior regions. Forty-five propensity score-matched patients were included in each group. In this matched sample, the prone group had a higher proportion of patients successfully weaned from VV-ECMO (64.4% vs. 42.2%; P = 0.035) and lower 60-day mortality (37.8% vs. 60.0%; P = 0.035).

Conclusions

Patients with severe ARDS placed in PP before VV-ECMO should continue PP after VV-ECMO support. This approach could increase the probability of successful weaning from VV-ECMO.

 

Barriers to female leadership in intensive care medicine: insights from an ESICM NEXT & Diversity Monitoring Group Survey

by Silvia De Rosa, Stefan J. Schaller, Laura Galarza, Ricard Ferrer, Bairbre A. McNicholas, Max Bell, Julie Helms, Elie Azoulay and Antoine Vieillard-Baron 

Annals of Intensive Care volume 14, Article number: 126 (2024) Published: 19 August 2024

Background

The underrepresentation of women in leadership remains a pervasive issue, prompting a critical examination of support mechanisms within professional settings. Previous studies have identified challenges women face, ranging from limited visibility to barriers to career advancement. This survey aims to investigate perceptions regarding the effectiveness of women’s leadership programs, mentoring initiatives, and a specialized communication course. Particularly it specifically targets addressing the challenges encountered by professional women.

Methods

This multi-center, observational, international online survey was developed in partnership between ESICM NEXT and the ESICM Diversity and Inclusiveness Monitoring Group for Healthcare. Invitations to participate were distributed to both females and men through emails and social networks. Data were collected from April 1, 2023, through October 1, 2023.

Results

Out of 354 respondents, 90 were men (25.42%) and 264 were women (74.58%). Among them, 251 completed the survey, shedding light on the persistent challenges faced by women in leadership roles, with 10%-50% of respondents holding such positions. Women’s assertiveness is viewed differently, with 65% recognizing barriers such as harassment. Nearly half of the respondent’s experience interruptions in meetings. Only 47.4% receiving conference invitations, with just over half accepting them. A mere 12% spoke at ESICM conferences in the last three years, receiving limited support from directors and colleagues, indicating varied obstacles for female professionals. Encouraging family participation, reducing fees, providing childcare, and offering economic support can enhance conference involvement. Despite 55% applying for ESICM positions, barriers like mobbing, harassment, lack of financial support, childcare, and language barriers were reported. Only 14% had access to paid family leave, while 32% benefited from subsidized childcare. Participation in the Effective Communication Course on Career Advancement Goals and engagement in women’s leadership and mentoring programs could offer valuable insights and growth opportunities. Collaborating with Human Resources and leadership allies is crucial for overcoming barriers and promoting women’s career growth.

Conclusions

The urgency of addressing identified barriers to female leadership in intensive care medicine is underscored by the survey’s comprehensive insights. A multifaceted and intersectional approach, considering sexism, structural barriers, and targeted strategies, is essential.

 

Assessing palliative care practices in intensive care units and interpreting them using the lens of appropriate care concepts. An umbrella review

Intensive Care Medicine, Published: 14 August 2024

Purpose

Intensive care units (ICUs) have significant palliative care needs but lack a reliable care framework. This umbrella review addresses them by synthesising palliative care practices provided at end-of-life to critically ill patients and their families before, during, and after ICU admission.

Methods

Seven databases were systematically searched for systematic reviews, and the umbrella review was conducted according to the guidelines laid out by the Joanna Briggs Institute (JBI).

Results

Out of 3122 initial records identified, 40 systematic reviews were included in the synthesis. Six key themes were generated that reflect the palliative and end-of-life care practices in the ICUs and their outcomes. Effective communication and accurate prognostications enabled families to make informed decisions, cope with uncertainty, ease distress, and shorten ICU stays. Inter-team discussions and agreement on a plan are essential before discussing care goals. Recording care preferences prevents unnecessary end-of-life treatments. Exceptional end-of-life care should include symptom management, family support, hydration and nutrition optimisation, avoidance of unhelpful treatments, and bereavement support. Evaluating end-of-life care quality is critical and can be accomplished by seeking family feedback or conducting a survey.

Conclusion

This umbrella review encapsulates current palliative care practices in ICUs, influencing patient and family outcomes and providing insights into developing an appropriate care framework for critically ill patients needing end-of-life care and their families.

 

Sex matters: Is it time for a SOFA makeover?

by Emma Larsson 

Critical Care 28, Article number: 268 (2024) Published 8 August 2024

While sepsis affects individuals regardless of sex, emerging research has highlighted notable differences in how women and men experience, respond to, and recover from sepsis treated in intensive care units (ICU). These differences are influenced by a complex interplay of biological, hormonal, and sociocultural factors. As we explore sepsis management in ICU settings, it becomes evident that understanding the factors contributing to these sex-based variations is important for tailoring therapeutic approaches and improving overall patient outcomes. Moreover, for a nuanced interpretation of current evidence, it is worth noting the distinction between the terms gender and sex: gender refers to the socially constructed roles and behaviors that a given society considers appropriate, while sex pertains to biological characteristics...

Critical Care Bulletin - July 2024

 

Breathlessness assessment, management and impact in the intensive care unit: a rapid review and narrative synthesis

 

by Ben R. Richardson, Maxens Decavèle, Alexandre Demoule, Fliss E. M. Murtagh and Miriam J. Johnson 

 

Annals of Intensive Care volume 14, Article number: 107, Published: 05 July 2024

 

Background

Adults in the intensive care unit (ICU) commonly experience distressing symptoms and other concerns such as pain, delirium, and breathlessness. Breathlessness management is not supported by any ICU guidelines, unlike other symptoms.

Aim

To review the literature relating to (i) prevalence, intensity, assessment, and management of breathlessness in critically ill adults in the ICU receiving invasive and non-invasive mechanical ventilation (NIV) and high-flow oxygen therapy, (HFOT), (ii) the impact of breathlessness on ICU patients with regard to engagement with rehabilitation.

Methods

A rapid review and narrative synthesis using the Cochrane Methods Group Recommendations was conducted and reported in accordance with PRISMA. All study designs investigating breathlessness in adult ICU patients receiving either invasive mechanical ventilation (IMV), NIV or HFOT were eligible. PubMed, MEDLINE, The Cochrane Library and CINAHL databased were searched from June 2013 to June 2023. Studies were quality appraised.

Results

19 studies representing 2822 ICU patients were included (participants mean age 48 years to 71 years; proportion of males 43–100%). The weighted mean prevalence of breathlessness in ICU patients receiving IMV was 49% (range 34–66%). The proportion of patients receiving NIV self-reporting moderate to severe dyspnoea was 55% prior to initiation. Breathlessness assessment tools included visual analogue scale, (VAS), numerical rating scale, (NRS) and modified BORG scale, (mBORG). In patients receiving NIV the highest reported median (interquartile range [IQR]) VAS, NRS and mBORG scores were 6.2cm (0–10 cm), 5 (2–7) and 6 (2.3–7) respectively (moderate to severe breathlessness). In patients receiving either NIV or HFOT the highest reported median (IQR) VAS, NRS and mBORG scores were 3 cm (0–6 cm), 8 (5–10) and 4 (3–5) respectively.

Conclusion

Breathlessness in adults receiving IMV, NIV or HFOT in the ICU is prevalent and clinically important with median intensity ratings indicating the presence of moderate to severe symptoms.

 

Recruitment-to-inflation ratio reflects the impact of peep on dynamic lung strain in a highly recruitable model of ARDS

 

by Francesco Murgolo, Domenico L. Grieco, Savino Spadaro, Nicola Bartolomeo, Rossella di Mussi, Luigi Pisani, Marco Fiorentino, Alberto Maria Crovace, Luca Lacitignola, Francesco Staffieri and Salvatore Grasso 

 

Annals of Intensive Care volume 14, Article number: 106, Published: 04 July 2024

 

Background

The recruitment-to-inflation ratio (R/I) has been recently proposed to bedside assess response to PEEP. The impact of PEEP on ventilator-induced lung injury depends on the extent of dynamic strain reduction. We hypothesized that R/I may reflect the potential for lung recruitment (i.e. recruitability) and, consequently, estimate the impact of PEEP on dynamic lung strain, both assessed through computed tomography scan.

Methods

Fourteen lung-damaged pigs (lipopolysaccharide infusion) underwent ventilation at low (5 cmH2O) and high PEEP (i.e., PEEP generating a plateau pressure of 28–30 cmH2O). R/I was measured through a one-breath derecruitment maneuver from high to low PEEP. PEEP-induced changes in dynamic lung strain, difference in nonaerated lung tissue weight (tissue recruitment) and amount of gas entering previously nonaerated lung units (gas recruitment) were assessed through computed tomography scan. Tissue and gas recruitment were normalized to the weight and gas volume of previously ventilated lung areas at low PEEP (normalized-tissue recruitment and normalized-gas recruitment, respectively).

Results

Between high (median [interquartile range] 20 cmH2O [18–21]) and low PEEP, median R/I was 1.08 [0.88–1.82], indicating high lung recruitability. Compared to low PEEP, tissue and gas recruitment at high PEEP were 246 g [182–288] and 385 ml [318–668], respectively. R/I was linearly related to normalized-gas recruitment (r = 0.90; [95% CI 0.71 to 0.97) and normalized-tissue recruitment (r = 0.69; [95% CI 0.25 to 0.89]). Dynamic lung strain was 0.37 [0.29–0.44] at high PEEP and 0.59 [0.46–0.80] at low PEEP (p < 0.001). R/I was significantly related to PEEP-induced reduction in dynamic (r = − 0.93; [95% CI − 0.78 to − 0.98]) and global lung strain (r = − 0.57; [95% CI − 0.05 to − 0.84]). No correlation was found between R/I and and PEEP-induced changes in static lung strain (r = 0.34; [95% CI − 0.23 to 0.74]).

Conclusions

In a highly recruitable ARDS model, R/I reflects the potential for lung recruitment and well estimates the extent of PEEP-induced reduction in dynamic lung strain.

 

The use of Guyton’s approach to the control of cardiac output for clinical fluid management

by Sheldon Magder 

Annals of Intensive Care volume 14, Article number: 105, Published: 04 July 2024

Abstract

Infusion of fluids is one of the most common medical acts when resuscitating critically ill patients. However, fluids most often are given without consideration of how fluid infusion can actually improve tissue perfusion. Arthur Guyton’s analysis of the circulation was based on how cardiac output is determined by the interaction of the factors determining the return of blood to the heart, i.e. venous return, and the factors that determine the output from the heart, i.e. pump function. His theoretical approach can be used to understand what fluids can and cannot do. In his graphical analysis, right atrial pressure (RAP) is at the center of this interaction and thus indicates the status of these two functions. Accordingly, trends in RAP and cardiac output (or a surrogate of cardiac output) can provide important guides for the cause of a hemodynamic deterioration, the potential role of fluids, the limits of their use, and when the fluid is given, the response to therapeutic interventions. Use of the trends in these values provide a physiologically grounded approach to clinical fluid management.

 

Upper gastrointestinal bleeding on veno-arterial extracorporeal membrane oxygenation support

 

by Quentin de Roux, Yekcan Disli, Wulfran Bougouin, Marie Renaudier, Ali Jendoubi, Jean-Claude Merle, Mathilde Delage, Lucile Picard, Faiza Sayagh, Chamsedine Cherait, Thierry Folliguet, Christophe Quesnel, Aymeric Becq and Nicolas Mongardon 

 

Annals of Intensive Care volume 14, Article number: 104, Published: 03 July 2024

 

Introduction

Patients on veno-arterial extracorporeal membrane oxygenation (V-A ECMO) support are at a high risk of hemorrhagic complications, including upper gastrointestinal bleeding (UGIB). The objective of this study was to evaluate the incidence and impact of this complication in V-A ECMO patients.

Materials and methods

A retrospective single-center study (2013–2017) was conducted on V-A ECMO patients, excluding those who died within 24 h. All patients with suspected UGIB underwent esophagogastroduodenoscopy (EGD) and were analyzed and compared to the remainder of the cohort, from the initiation of ECMO until 5 days after explantation.

Results

A total of 150 V-A ECMO cases (65 after cardiac surgery and 85 due to medical etiology) were included. 90% of the patients received prophylactic proton pump inhibitor therapy and enteral nutrition. Thirty-one patients underwent EGD for suspected UGIB, with 16 confirmed cases of UGIB. The incidence was 10.7%, with a median occurrence at 10 [7–17] days. There were no significant differences in clinical or biological characteristics on the day of EGD. However, patients with UGIB had significant increases in packed red blood cells and fresh frozen plasma needs, mechanical ventilation duration and V-A ECMO duration, as well as in length of intensive care unit and hospital stays. There was no significant difference in mortality. The only independent risk factor of UGIB was a history of peptic ulcer (OR = 7.32; 95% CI [1.07–50.01], p = 0.042).

Conclusion

UGIB occurred in at least 1 out of 10 cases of V-A ECMO patients, with significant consequences on healthcare resources. Enteral nutrition and proton pump inhibitor prophylaxis did not appear to protect V-A ECMO patients. Further studies should assess their real benefits in these patients with high risk of hemorrhage.