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Background: This study was designed to evaluate the feasibility of propofol infusion by a closed-loop system for the titration of anaesthetic induction guided by Bispectral Index. Methods: Forty patients were prospectively and randomly allocated into two groups: the target control infusion (TCI) group, where propofol titration was performed manually guided by the Bispectral Index using a commercial pharmacokinetic model (Diprifusor device) and the closed-loop group where titration was performed using a proportional differential algorithm. For both groups, the objective was to achieve a Bispectral Index of 50. Remifentanil TCI was infused at a target of 2 ng mL-1 and was maintained constant throughout the study. Feasibility of automatic induction was evaluated with performance error and haemodynamic data. Results: Bispectral Index overshoot (-9 ± 13% vs. -16 ± 20%, P = 0.035) and mean duration of induction (381 ± 106s vs. 490 ± 131s, P = 0.004) were lower in the closed-loop group than in the TCI group. Haemodynamic data were similar between groups with a similar use of ephedrine bolus. Conclusion: The system was able to allow induction clinically for all patients. Automated titration guided by Bispectral Index for propofol infusion was feasible without increase in haemodynamic adverse effects. [ABSTRACT FROM AUTHOR]

Background: The impact of albumin use during major surgery is unknown, and a dearth of evidence governing its use in major noncardiac surgery has long precluded its standardization in clinical guidelines., Objective: In this study, we investigate institutional variation in albumin use among medical centers in the United States during major noncardiac surgery and explore the association of intraoperative albumin administration with important postoperative outcomes., Methods: The study is an observational retrospective cohort analysis performed among 54 U.S. hospitals in the Multicenter Perioperative Outcomes Group and includes adult patients who underwent major noncardiac surgery under general anesthesia between January 2014 and June 2020. The primary endpoint was the incidence of albumin administration. Secondary endpoints are acute kidney injury (AKI), net-positive fluid balance, pulmonary complications, and 30-day mortality. Albumin-exposed and albumin-unexposed cases were compared within a propensity score-matched cohort to evaluate associations of albumin use with outcomes., Results: Among 614,215 major surgeries, predominantly iso-oncotic albumin was administered in 15.3% of cases and featured significant inter-institutional variability in use patterns. Cases receiving intraoperative albumin involved patients of higher American Society of Anesthesiologists physical status and featured larger infused crystalloid volumes, greater blood loss, and vasopressor use. Overall, albumin was most often administered at high-volume surgery centers with academic affiliation, and within a propensity score-matched cohort (n=153,218), the use of albumin was associated with AKI (aOR 1.24, 95% CI 1.20-1.28, P <0.001), severe AKI (aOR 1.45, 95% CI 1.34-1.56, P <0.001), net-positive fluid balance (aOR 1.18, 95% CI 1.16-1.20, P <0.001), pulmonary complications (aOR 1.56, 95% CI 1.30-1.86, P <0.001), and 30-day all-cause mortality (aOR 1.37, 95% CI 1.26-1.49, P <0.001)., Conclusions: Intravenous albumin is commonly administered among noncardiac surgeries with significant inter-institutional variability in use in the United States. Albumin administration was associated with an increased risk of postoperative complications., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Acute hypotensive episodes (AHE), defined as a drop in the mean arterial pressure (MAP) <65 mm Hg lasting at least 5 consecutive minutes, are among the most critical events in the intensive care unit (ICU). They are known to be associated with adverse outcome in critically ill patients. AHE prediction is of prime interest because it could allow for treatment adjustment to predict or shorten AHE., Methods: The Super Learner (SL) algorithm is an ensemble machine-learning algorithm that we specifically trained to predict an AHE 10 minutes in advance. Potential predictors included age, sex, type of care unit, severity scores, and time-evolving characteristics such as mechanical ventilation, vasopressors, or sedation medication as well as features extracted from physiological signals: heart rate, pulse oximetry, and arterial blood pressure. The algorithm was trained on the Medical Information Mart for Intensive Care dataset (MIMIC II) database. Internal validation was based on the area under the receiver operating characteristic curve (AUROC) and the Brier score (BS). External validation was performed using an external dataset from Lariboisière hospital, Paris, France., Results: Among 1151 patients included, 826 (72%) patients had at least 1 AHE during their ICU stay. Using 1 single random period per patient, the SL algorithm with Haar wavelets transform preprocessing was associated with an AUROC of 0.929 (95% confidence interval [CI], 0.899-0.958) and a BS of 0.08. Using all available periods for each patient, SL with Haar wavelets transform preprocessing was associated with an AUROC of 0.890 (95% CI, 0.886-0.895) and a BS of 0.11. In the external validation cohort, the AUROC reached 0.884 (95% CI, 0.775-0.993) with 1 random period per patient and 0.889 (0.768-1) with all available periods and BSs <0.1., Conclusions: The SL algorithm exhibits good performance for the prediction of an AHE 10 minutes ahead of time. It allows an efficient, robust, and rapid evaluation of the risk of hypotension that opens the way to routine use.

Objectives: Neutropenic enterocolitis occurs in about 5.3% of patients hospitalized for hematologic malignancies receiving chemotherapy. Data from critically ill patients with neutropenic enterocolitis are scarce. Our objectives were to describe the population of patients with neutropenic enterocolitis admitted to an ICU and to investigate the risk factors of invasive fungal disease., Design: A multicentric retrospective cohort study between January 2010 and August 2017., Setting: Six French ICUs members of the Groupe de Recherche Respiratoire en Onco-Hématologie research network., Patients: Adult neutropenic patients hospitalized in the ICU with a diagnosis of enteritis and/or colitis. Patients with differential diagnosis (Clostridium difficile colitis, viral colitis, inflammatory enterocolitis, mesenteric ischemia, radiation-induced gastrointestinal toxicity, and Graft vs Host Disease) were excluded., Interventions: None., Measurement and Main Results: We included 134 patients (median Sequential Organ Failure Assessment 10 [8-12]), with 38.8% hospital mortality and 32.1% ICU mortality rates. The main underlying malignancies were acute leukemia (n = 65, 48.5%), lymphoma (n = 49, 36.6%), solid tumor (n = 14, 10.4%), and myeloma (n = 4, 3.0%). Patients were neutropenic during a median of 14 days (9-22 d). Infection was documented in 81 patients (60.4%), including an isolated bacterial infection in 64 patients (47.8%), an isolated fungal infection in nine patients (6.7%), and a coinfection with both pathogens in eight patients (5.0%). Radiologically assessed enteritis (odds ratio, 2.60; 95% CI, 1.32-7.56; p = 0.015) and HIV infection (odds ratio, 2.03; 95% CI, 1.21-3.31; p = 0.016) were independently associated with invasive fungal disease., Conclusions: The rate of invasive fungal disease reaches 20% in patients with neutropenic enterocolitis when enteritis is considered. To avoid treatment delay, antifungal therapy might be systematically discussed in ICU patients admitted for neutropenic enterocolitis with radiologically assessed enteritis.

Objectives: The Fragility Index, which represents the number of patients responsible for a statistically significant finding, has been suggested as an aid for interpreting the robustness of results from clinical trials. A small Fragility Index indicates that the statistical significance of a trial depends on only a few events. Our objectives were to calculate the Fragility Index of statistically significant results from randomized controlled trials of anesthesia and critical care interventions and to determine the frequency of distorted presentation of results or "spin"., Data Sources: We systematically searched MEDLINE from January 01, 2007, to February 22, 2017, to identify randomized controlled trials exploring the effect of critical care medicine or anesthesia interventions., Study Selection: Studies were included if they randomized patients 1:1 into two parallel arms and reported at least one statistically significant (p < 0.05) binary outcome (primary or secondary)., Data Extraction: Two reviewers independently assessed eligibility and extracted data. The Fragility Index was determined for the chosen outcome. We assessed the level of spin in negative trials and the presence of recommendations for clinical practice in positive trials., Data Synthesis: We identified 166 eligible randomized controlled trials with a median sample size of 207 patients (interquartile range, 109-497). The median Fragility Index was 3 (interquartile range, 1-7), which means that adding three events to one of the trials treatment arms eliminated its statistical significance. High spin was identified in 42% (n = 30) of negative randomized controlled trials, whereas 21% (n = 20) of positive randomized controlled trials provided recommendations. Lower levels of spin and recommendations were associated with publication in journals with high impact factors (p < 0.001 for both)., Conclusions: Statistically significant results in anesthesia and critical care randomized controlled trials are often fragile, and study conclusions are frequently affected by spin. Routine calculation of the Fragility Index in medical literature may allow for better understanding of trials and therefore enhance the quality of reporting.

Objectives: To determine whether a policy based on provisional replacement of catheters every 5 days had an impact on the incidence of arterial catheter-related bloodstream infections in a population of adult surgical intensive care unit patients., Design: Prepost study in which all patients with an arterial catheter who were admitted between 1997 and 2004 were observed. Scheduled replacement of arterial catheters every 5 days during period A (before 2000) was compared to nonscheduled replacement during period B (after 2000)., Setting: A 20-bed surgical intensive care unit at a French university hospital., Patients: All intensive care unit patients requiring an arterial catheter., Interventions: Modification to the catheter maintenance policies between period A and period B., Measurements and Main Results: A total of 1,672 consecutive patients were included, and 3,247 arterial catheters were analyzed, yielding an average number of 1.9 (sd, 1.7) arterial catheters per patient. The rate of colonization (14.2% before 2000 vs. 16.4% after 2000; p = .10) and the incidence density of arterial catheter colonization (31.32 [95% confidence interval] 27.07-36.25 per 1,000 catheter-days before 2000 vs. 29.79 [95% confidence interval, 26.72-33.21] per 1,000 catheter-days after 2000; p = .11) did not differ significantly between the two periods. However, the rate of arterial catheter-related bloodstream infections (1.4% before 2000 vs. 0.6% after 2000; p = .01) and the arterial catheter-related bloodstream infections incidence density (3.13 [95% confidence interval, 1.97-4.97] before 2000 vs. 1.01 [95% confidence interval, 0.56-1.82] per 1,000 catheter-days after 2000; p < .0001) was significantly higher before 2000., Conclusion: Discontinuation of scheduled replacement of arterial catheters every 5 days did not increase the risk of colonization but decreased the risk of bloodstream infections.

Background: The resuscitation strategy for hemorrhagic shock remains controversial, with the kidney being especially prone to hypoxia., Methods: The authors used a three-phase hemorrhagic shock model to investigate the effects of fluid resuscitation on renal oxygenation. After a 1-h shock phase, rats were randomized into four groups to receive either normal saline or hypertonic saline targeting a mean arterial pressure (MAP) of either 40 or 80 mmHg. After such resuscitation, rats were transfused with the shed blood. Renal macro- and microcirculation were monitored with cortical and outer-medullary microvascular oxygen pressure, renal oxygen delivery, and renal oxygen consumption measured using oxygen-dependent quenching of phosphorescence., Results: Hemorrhagic shock was characterized by a drop of aortic blood flow, MAP, renal blood flow, renal oxygen delivery, renal oxygen consumption, and renal microvascular PO2. During the fluid resuscitation phase, normal saline targeting a MAP = 80 mmHg was the sole strategy able to restore aortic blood flow, renal blood flow, and renal oxygen consumption, although without improving renal oxygen delivery. However, none of the strategies using either normal saline or hypertonic saline or targeting a high MAP could restore the renal microvascular Po2. Blood transfusion increased microvascular Po2 but was unable to totally restore renal microvascular oxygenation to baseline values., Conclusions: This experimental rat study shows that (1) high MAP-directed fluid resuscitation (80 mmHg) does not lead to higher renal microvascular Po2 compared with fluid resuscitation targeted to MAP (40 mmHg); (2) hypertonic saline is not superior to normal saline regarding renal oxygenation; and (3) decreased renal oxygenation persists after blood transfusion.

Background: : Ventilator-associated pneumonia is associated with an increase in morbidity and mortality. The delay before adequate antibiotherapy is known to influence patients' outcome. We hypothesized that the results of upper airways samples performed at immediately intensive care unit admission could help the clinician to choose the adequate empiric antibiotherapy for a ventilator-associated pneumonia occurring during the first 5 days of intensive care unit admission., Objectives: : To compare the bacterial content of the upper airways samples to that of the pulmonary plugged specimen performed when ventilator-associated pneumonia was suspected., Design: : Prospective observational study., Setting: : Twenty beds in a surgical intensive care unit of a teaching hospital., Patients: : All patients between 1996 and 2001, who were ventilated for more than 48 hours and presented a suspicion of ventilator-associated pneumonia, occurring during the first 5 days., Interventions: : As compared to the results of pulmonary plugged specimen, upper airways samples performance was tested by determining sensitivity, specificity, and positive likelihood ratios for each microorganism., Measurements and Main Results: : Five hundred eighty-eight patients ventilated for more than 48 hours were suspected to suffer from a VAP and benefited from a pulmonary plugged specimen: 136 (48%) patients had a positive pulmonary plugged specimen and received antibiotics. Of these 136, 125 (92%) had had a positive upper airway samples at intensive care unit admission. For all microorganisms, upper airway sample specificity exceeded 85%. For all bacteria except Streptococcus species, the likelihood ratios exceeded 6, threshold considered as significant to rule in the diagnosis., Conclusions: : In this study, we found high specificities and likelihood ratios for upper airways samples to predict the microorganisms involved in a ventilator-associated pneumonia. These results suggest that upper airways samples might provide an adjunctive assistance in selecting therapy for ventilator-associated pneumonia.

Purpose of Review: B-type natriuretic peptides are quantitative markers of heart failure (and/or cardiac stress) that summarize the extent of systolic and diastolic left ventricular dysfunction, valvular dysfunction, and right ventricular dysfunction. Based on the observation that heart failure is common albeit difficult to diagnose in the ICU, several studies have begun to evaluate the potential use of B-type natriuretic peptides in various ICU settings., Recent Findings: Previous pilot studies have examined the use of B-type natriuretic peptide in the differential diagnosis of hypoxemic respiratory failure, to differentiate cardiogenic from noncardiogenic shocks or to predict fluid responsiveness, to assess myocardial dysfunction and prognosis in patients with severe sepsis, and to predict ventilatory weaning failure., Summary: Although previous studies were small, they highlight the potential of using B-type natriuretic peptides as a noninvasive easily available tool to quantify cardiac stress.