Annals of Intensive Care最新文献

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.

Background: The optimal timing of weaning from venovenous extracorporeal membrane oxygenation (VV ECMO) and its modalities have been rarely studied.

Methods: Retrospective, multicenter cohort study over 7 years in two tertiary ICUs, high-volume ECMO centers in France and Italy. Patients with ARDS on ECMO and successfully weaned from VV ECMO were classified based on their mechanical ventilation modality during the sweep gas-off trial (SGOT) with either controlled mechanical ventilation or spontaneous breathing (i.e. pressure support ventilation). The primary endpoint was the time to successful weaning from mechanical ventilation within 90 days post-ECMO weaning.

Results: 292 adult patients with severe ARDS were weaned from controlled ventilation, and 101 were on spontaneous breathing during SGOT. The 90-day probability of successful weaning from mechanical ventilation was not significantly different between the two groups (sHR [95% CI], 1.23 [0.84-1.82]). ECMO-related complications were not statistically different between patients receiving these two mechanical ventilation strategies. After adjusting for covariates, older age, higher pre-ECMO sequential organ failure assessment score, pneumothorax, ventilator-associated pneumonia, and renal replacement therapy, but not mechanical ventilation modalities during SGOT, were independently associated with a lower probability of successful weaning from mechanical ventilation after ECMO weaning.

Conclusions: Time to successful weaning from mechanical ventilation within 90 days post-ECMO was not associated with the mechanical ventilation strategy used during SGOT. Further research is needed to assess the optimal ventilation strategy during weaning off VV ECMO and its impact on short- and long-term outcomes.

Background: The coronavirus-related disease (COVID-19) is mainly characterized by a respiratory involvement. The renin-angiotensin system (RAS) has a relevant role in the pathogenesis of COVID-19, as the virus enters host's cells via the angiotensin-converting enzyme 2 (ACE2).

Methods: This investigator-initiated, seamless phase 1-2 randomized clinical trial was conceived to test the safety and efficacy of continuous short-term (up to 7 days) intravenous administration of Angiotensin-(1-7) in COVID-19 patients admitted to two intensive care units (ICU). In addition to standard of care, intravenous administration of Angiotensin-(1-7) was started at 5 mcg/Kg day and increased to 10 mcg/Kg day after 24 h (Phase 1; open label trial) or given at 10 mcg/Kg day and continued for a maximum of 7 days or until ICU discharge (Phase 2; double-blind randomized controlled trial). The rate of serious adverse events (SAEs) served as the primary outcome of the study for Phase 1, and the number of oxygen free days (OFDs) by day 28 for Phase 2.

Results: Between August 2020 and July 2021, when the study was prematurely stopped due to low recruitment rate, 28 patients were included in Phase 1 and 79 patients in Phase 2. Of those, 78 were included in the intention to treat analysis, and the primary outcome was available for 77 patients. During Phase 1, one SAE (i.e., bradycardia) was considered possibly related to the infusion, justifying its discontinuation. In Phase 2, OFDs did not differ between groups (median 19 [0-21] vs. 14 [0-18] days; p = 0.15). When patients from both phases were analyzed in a pooled intention to treat approach (Phase 1-2 trial), OFDs were significantly higher in treated patients, when compared to controls (19 [0-21] vs. 14 [0-18] days; absolute difference -5 days, 95% CI [0-7] p = 0.04).

Conclusions: The main findings of our study indicate that continuous intravenous infusion of Angiotensin-(1-7) at 10 mcg/Kg day in COVID-19 patients admitted to the ICU with severe pneumonia is safe. In Phase II intention to treat analysis, there was no significant difference in OFD between groups. Trial Registration ClinicalTrials.gov Identifier: NCT04633772-Registro Brasileiro de Ensaios Clínicos, UTN number: U1111-1255-7167.

Background: Severe trauma is the leading cause of disability and mortality in the patients under 35 years of age. Surgical site infections (SSI) represent a significant complication in this patient population. However, they are often inadequately investigated, potentially impacting the quality of patient outcomes. The aim of this study was to investigate the epidemiology of SSI and risk factors in severe trauma patients.

Methods: We conducted a multicenter retrospective cohort study screening the severe trauma patients (STP) admitted to two intensive care units of an academic institution in Marseille between years2018 and 2019. Those who underwent orthopedic or spinal surgery within 5 days after admission were included and classified into two groups according to the occurrence of SSI (defined by the Centers for Disease Control (CDC) international diagnostic criteria) or not. Our secondary goal was to evaluate STP survival at 48 months, risk factors for SSI and microbiological features of SSI.

Results: Forty-seven (23%) out of 207 STP developed an SSI. Mortality at 48-months did not differ between SSI and non-SSI patients (12.7% vs. 10.0%; p = 0.59). The fractures of 22 (47%) severe trauma patients with SSI were classified as Cauchoix 3 grade and 18 (38%) SSI were associated with the need for external fixators. Thirty (64%) severe trauma patients with SSI had polymicrobial infection, including 34 (72%) due to Gram-positive cocci. Empirical antibiotic therapy was effective in 31 (66%) cases. Multivariate analysis revealed that risk factors such as low hemoglobin, arterial oxygenation levels, hyperlactatemia, high serum creatinine and glycemia, and Cauchoix 3 grade on the day of surgery were associated with SSI in severe trauma patients. The generated predictive model showed a good prognosis performance with an AUC of 0.80 [0.73-0.88] and a high NPV of 95.9 [88.6-98.5] %.

Conclusions: Our study found a high rate of SSI in severe trauma patients, although SSI was not associated with 48-month mortality. Several modifiable risk factors for SSI may be effectively managed through enhanced perioperative monitoring and the implementation of a patient blood management strategy.

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.

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.

Background: Optimal balance between macro- and microcirculation in critically ill patients is crucial for ensuring optimal organ perfusion. Nitric oxide (NO) is a regulator of vascular hemostasis and tone. The availability of NO is controlled by asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), and the availability of the NO substrates arginine and homoarginine. We investigated the changes in plasma concentrations of ADMA, SDMA, arginine, and homoarginine days 1-5 of intensive care unit (ICU) admission and the association between the change in concentration days 1-3 and 30-day all-cause mortality.

Methods: Single-center cohort study of adult critically ill patients from the ICU at Copenhagen University Hospital - North Zealand. ADMA, SDMA, arginine, and homoarginine (NO-biomarkers) were measured on days 1-5. Initially, we determined the changes in NO-biomarkers days 1-5 with linear mixed models, and subsequently how the changes in NO-biomarkers days 1-3 were associated with 30-day all-cause mortality. Post-hoc we analyzed the association between plasma concentration at admission and 30-day all-cause mortality.

Results: In total 567 out of 577 patients had plasma samples from days 1-5. Plasma concentrations of ADMA and arginine increased from days 1-5. SDMA concentrations increased from days 1-2, followed by a decrease from days 2-5. Concentrations of homoarginine did not change from days 1-3 but slightly increased from days 3-5. In total 512 patients were alive 3 days after ICU admission. Among these patients, a daily twofold increase in ADMA concentration from days 1-3 was associated with decreased mortality in multivariate analysis (HR 0.45; 95% CI 0.21-0.98; p = 0.046). An increase in SDMA, arginine, or homoarginine was not associated with mortality. Post-hoc we found that a twofold increase in ADMA or SDMA concentrations at admission was associated with mortality (HR 1.78; 95% CI 1.24-2.57; p = 0.0025, and HR 1.41; 95% CI 1.05-1.90; p = 0.024, respectively).

Conclusions: Increasing ADMA concentrations on days 1-3 are inversely associated with mortality, however not with the same strength as high ADMA or SDMA concentrations at admission. We suggest that admission concentrations are the focus of future research on ADMA and SDMA as predictors of mortality or potential therapeutical targets in ICU patients.

Background: By controlling hypercapnia, respiratory acidosis, and associated consequences, extracorporeal CO₂ removal (ECCO₂R) has the potential to facilitate ultra-protective lung ventilation (UPLV) strategies and to decrease injury from mechanical ventilation. We convened a meeting of European intensivists and nephrologists and used a modified Delphi process to provide updated insights into the role of ECCO₂R in acute respiratory distress syndrome (ARDS) and to identify recommendations for a future randomized controlled trial.

Results: The group agreed that lung protective ventilation and UPLV should have distinct definitions, with UPLV primarily defined by a tidal volume (V_T) of 4-6 mL/kg predicted body weight with a driving pressure (ΔP) ≤ 14-15 cmH₂O. Fourteen (93%) participants agreed that ECCO₂R would be needed in the majority of patients to implement UPLV. Furthermore, 10 participants (majority, 63%) would select patients with PaO₂:FiO₂ > 100 mmHg (> 13.3 kPa) and 14 (consensus, 88%) would select patients with a ventilatory ratio of > 2.5-3. A minimum CO₂ removal rate of 80 mL/min delivered by continuous renal support machines was suggested (11/14 participants, 79%) for this objective, using a short, double-lumen catheter inserted into the right internal jugular vein as the preferred vascular access. Of the participants, 14/15 (93%, consensus) stated that a new randomized trial of ECCO₂R is needed in patients with ARDS. A ΔP of ≥ 14-15 cmH₂O was suggested by 12/14 participants (86%) as the primary inclusion criterion.

Conclusions: ECCO₂R may facilitate UPLV with lower volume and pressures provided by the ventilator, while controlling respiratory acidosis. Since recent European Society of Intensive Care Medicine guidelines on ARDS recommended against the use of ECCO₂R for the treatment of ARDS outside of randomized controlled trials, new trials of ECCO₂R are urgently needed, with a ΔP of ≥ 14-15 cmH₂O suggested as the primary inclusion criterion.

Background: Nitric oxide (NO) is a strong vasodilator, selectively directed on pulmonary circulation through inhaled administration. In adult intensive care units (ICU), it is mainly used for refractory hypoxemia in mechanically ventilated patients. Several medical delivery devices have been developed to deliver inhaled nitric oxide (iNO). The main purpose of those devices is to guarantee an accurate inspiratory NO concentration, whatever the ventilator used, with NO₂ concentrations lower than 0.3 ppm. We hypothesized that the performances of the different available iNO delivery systems could depend on their working principle and could be influenced by the ventilator settings. The objective of this study was to assess the accuracy of seven different iNO-devices combined with different ICU ventilators' flow-by to reach inspiratory NO concentration targets and to evaluate their potential risk of toxicity.

Methods: We tested seven iNO-devices on a test-lung connected to distinct ICU ventilators offering four different levels of flow-by. We measured the flow in the inspiratory limb of the patient circuit and the airway pressure. The nitric oxide/nitrogen (NO/N₂) flow was measured on the administration line of the iNO-devices. NO and NO₂ concentrations were measured in the test-lung using an electrochemical analyzer.

Results: We identified three iNO-device generations based on the way they deliver NO flow: "Continuous", "Sequential to inspiratory phase" (I-Sequential) and "Proportional to inspiratory and expiratory ventilator flow" (Proportional). Median accuracy of iNO concentration measured in the test lung was 2% (interquartile range, IQR -19; 36), -23% (IQR -29; -17) and 0% (IQR -2; 0) with Continuous, I-Sequential and Proportional devices, respectively. Increased ventilator flow-by resulted in decreased iNO concentration in the test-lung with Continuous and I-Sequential devices, but not with Proportional ones. NO₂ formation measured to assess potential risks of toxicity never exceeded the predefined safety target of 0.5 ppm. However, NO₂ concentrations higher than or equal to 0.3 ppm, a concentration that can cause bronchoconstriction, were observed in 19% of the different configurations.

Conclusion: We identified three different generations of iNO-devices, based on their gas administration modalities, that were associated with highly variable iNO concentrations' accuracy. Ventilator's flow by significantly impacted iNO concentration. Only the Proportional devices permitted to accurately deliver iNO whatever the conditions and the ventilators tested.