Annals of Intensive Care最新文献

Background: Neurally Adjusted Ventilatory Assist (NAVA) compared to Pressure Support Ventilation (PSV) improves patient-ventilator interactions in intensive care unit. No study has evaluated NAVA in patients with obesity. We aimed to assess the feasibility and safety of NAVA in patients with obesity, and to compare NAVA in patients with versus without obesity.

Methods: In this randomized cross-over study, all respiratory cycles during 1 h of mechanical ventilation from 10 patients with obesity and 11 without obesity were analyzed. Patients underwent 30 min of NAVA and 30 min of PSV in a random order. Flow, airway pressure and diaphragm electrical activity were continuously recorded. Arterial blood gases were obtained at baseline and at the end of each 30-min period. Patient-ventilator interactions were assessed with trigger delay, inspiratory time in excess, rate and type of dyssynchrony cycles. Variability of the ventilatory parameters was evaluated by the coefficient of variation (SD/mean).

Results: All patients concluded the study, with a total of 1790 ± 873 respiratory cycles analyzed per patient. In patients with obesity, NAVA versus PSV was associated with a significant reduction in trigger delay (0 [0-5] vs. 106 [34-125] ms, p < 0.05), inspiratory time in excess (96 [94-102] vs. 145 [137-202] ms, p < 0.01) and in ineffective efforts (0 [0-0.03] vs. 0.33 [0.23-0.37] events/min, p < 0.05). The global dyssynchrony index remained similar in both modes (2.2% [1.1-4.4] vs. 3.7% [2.4-5.6], p = 0.68). Compared to PSV, PaO2/FiO2 ratio significantly increased in NAVA, 238 mmHg [174-344] versus 207 mmHg [164-297], p < 0.05. The tidal volume was significantly lower during NAVA than during PSV, 6.7 mL/kg predicted body weight [5.9-7.1] versus 7.2 mL/kg [6.2-8.2], p < 0.05. Ventilatory variability was significantly higher with NAVA, 16% [11-21] versus 4% [2-4] in mean inspiratory airway pressure. These results were similar in patients without obesity and the obesity factor was never significant. No adverse event was observed in patients with and without obesity in both modes.

Conclusion: In patients with obesity, NAVA ventilation is feasible and safe, improves patient-ventilator interactions and oxygenation, with an increase ventilatory variability compared to PSV. The effects of NAVA are comparable in patients with and without obesity.

Background: Electrical impedance tomography (EIT) is a non-invasive, radiation free, lung imaging technique of lung ventilation with a low spatial but a high temporal resolution available at the bedside. Lung perfusion, and hence ventilation-to-perfusion ratios, can also be assessed with EIT. Most of the EIT studies in intensive care units (ICU) are dedicated to positive end expiratory pressure selection in patients with acute respiratory distress syndrome receiving invasive mechanical ventilation. This narrative review explores the use of EIT during change in body position, weaning and chest physiotherapy in adult intubated ICU patients.

Main body: EIT findings confirm a better ventilation and the persistence of lung perfusion in the dorsal lung regions in prone as compared to supine position. However, the response of the ventilation distribution to prone is heterogeneous across patients. For the weaning, global inhomogeneity index, end-expiratory lung impedance, absolute ventral-to-dorsal difference of the change in lung impedance and temporal skew of aeration had a good performance to predict spontaneous breathing trial (SBT) failure in some observational studies. Pendelluft that measures the risk of overstretching in dependent lung regions can only be assessed with EIT. It occurs frequently during weaning and is associated with poor patient outcome. However, its performance to predict SBT failure was moderate. Randomized controlled trials comparing SBT techniques did not find a difference in EIT indexes. The effects of other body positions and chest physiotherapy have been less investigated with EIT.

Conclusion: EIT offers the possibility to monitor lung ventilation and perfusion at the bedside and hence to deliver a personalized ventilatory management. Further designed EIT studies coupled with measurement of lung aeration and patient breathing effort are warranted during weaning to check if the technique is useful to clinical outcome. The same is true regarding the optimal use of body position including prone, and of chest physiotherapy in ICU patients.

Background: To investigate the adverse events, diagnostic yield, and therapeutic implications of liver biopsy in intensive-care-unit (ICU) patients.

Methods: Retrospective observational multicenter cohort study. Consecutive adults admitted to any of the four participating ICUs in France between January 1, 2006 and March 1, 2023, and who had a liver biopsy during the ICU stay were included.

Results: We included 139 patients (median age, 52 years; 69% male) biopsied via the transjugular (n = 97), percutaneous (n = 30), or laparoscopic (n = 1) route (missing data n = 11). The liver parenchyma was evaluable in 137/139 (99%) patients, who had 187 histological diagnoses in total. The pathological diagnoses matched the pre-biopsy diagnostic hypotheses in 83 (60%) patients. The most common were chronic or acute-on-chronic liver disease (n = 78, 56%), malignancy (n = 27, 19%), and infectious disease (n = 12, 9%). Among other diagnoses (n = 17, 12%), drug toxicity and biliary diseases predominated. The liver biopsy had therapeutic implications for 80 (58%) patients, among whom 66 (82%) received a new treatment, 7 (9%) were continued on empirically initiated treatment, and 7 (9%) were taken off the previous treatment. WHO grade 3-4 bleeding developed in 10 (7%) patients and was fatal in 2 patients. Higher severity scores, higher urea level, and absence of cirrhosis were associated with a greater risk of bleeding complications. Day-90 survival was not significantly different between the groups with vs. without therapeutic implications of the biopsy.

Conclusions: In ICU patients, liver biopsy provides a wide range of diagnoses and guides treatment decisions. However, the risk of potentially fatal bleeding is a major concern. We identified risk factors for bleeding.

Background: Whether Molecular Adsorbent Recirculating System (MARS) dialysis and high-volume plasma exchange (HVPE) may improve survival in acute liver failure (ALF) remains unclear. A referral center retrospective cohort study was conducted on patients admitted to ICU with ALF and who fulfilled liver transplantation (LTx) criteria from 2000 to 2021.

Methods: The whole study period was divided into three 7-year consecutive periods (A, B, C) depending on the patients' date of admission. MARS was optionally performed only in periods A and B and HVPE was only performed in period C. Day-21 transplant-free survival (TFS) and day-28 overall survival (OS) were endpoints. The effect of MARS was assessed in periods A and B by comparing the patients treated with MARS with those not treated. Three treatment groups consisting of two different durations of total MARS therapy or no MARS were also compared. HVPE-treated patients (period C, n = 45) were compared to a control group of patients receiving no liver support or a short duration of MARS therapy that was not considered to be effective (over periods A, B, C, n = 126). Survival curves were compared by the Gehan-Breslow-Wilcoxon test and the logrank test.

Results: 199 patients were enrolled and distributed as follows: A, n = 68; B, n = 70; C, n = 61. TFS did not differ with and without MARS (p = 0.19). Although MARS duration therapy could not be predicted at the time of MARS initiation, the patients treated ≥ 17 h (≥ 3 sessions) had better survival compared to treatment < 17 h or no MARS (78.6%, 30.4%, 43.8%; p = 0.0002). TFS was 55.6% versus 38.1% in the HVPE- and control groups (p = 0.003; adjusted HR 0.54 [0.32-0.93], p = 0.0257) and OS was 75.9% and 52.9%, respectively (p = 0.03).

Conclusions: MARS therapy improved TFS only in patients who received ≥ 3 sessions. Compared with controls, HVPE-treated patients experienced improved transplant-free and overall survival.