Assessment of diaphragmatic dysfunction in the critically ill patient with ultrasound: a systematic review.

PURPOSE: Diaphragmatic dysfunction (DD) has a high incidence in critically ill patients and is an under-recognized cause of respiratory failure and prolonged weaning from mechanical ventilation. Among different methods to assess diaphragmatic function, diaphragm ultrasonography (DU) is noninvasive, rapid, and easy to perform at the bedside. We systematically reviewed the current literature assessing the usefulness and accuracy of DU in intensive care unit (ICU) patients. METHODS: Pubmed, Cochrane Database of Systematic Reviews, Embase, Scopus, and Google Scholar Databases were searched for pertinent studies. We included all original, peer-reviewed studies about the use of DU in ICU patients. RESULTS: Twenty studies including 875 patients were included in the final analysis. DU was performed with different techniques to measure diaphragmatic inspiratory excursion, thickness of diaphragm (Tdi), and thickening fraction (TF). DU is feasible, highly reproducible, and allows one to detect diaphragmatic dysfunction in critically ill patients. During weaning from mechanical ventilation and spontaneous breathing trials, both diaphragmatic excursion and diaphragmatic thickening measurements have been used to predict extubation success or failure. Optimal cutoffs ranged from 10 to 14 mm for excursion and 30-36 % for thickening fraction. During assisted mechanical ventilation, diaphragmatic thickening has been found to be an accurate index of respiratory muscles workload. Observational studies suggest DU as a reliable method to assess diaphragm atrophy in patients undergoing mechanical ventilation. CONCLUSIONS: Current literature suggests that DU could be a useful and accurate tool to detect diaphragmatic dysfunction in critically ill patients, to predict extubation success or failure, to monitor respiratory workload, and to assess atrophy in patients who are mechanically ventilated.

Long-Term Survival Rate in Patients With Acute Respiratory Failure Treated With Noninvasive Ventilation in Ordinary Wards.

OBJECTIVE: Noninvasive ventilation is a life-saving technique increasingly used to treat acute respiratory failure. Noninvasive ventilation has been applied mostly in ICUs, but several reasons brought to an increasing application of noninvasive ventilation in ordinary wards. Few articles evaluated the outcomes of patients receiving noninvasive ventilation including long-term follow-up. The aim of the present study was to assess 1-year survival rate of patients treated with noninvasive ventilation outside the ICU for acute respiratory failure of heterogeneous causes and to identify the predictors of long-term mortality. DESIGN: Prospective, observational, pragmatic study. SETTING: Ordinary wards of a teaching hospital. PATIENTS: Consecutive patients treated with noninvasive ventilation for acute respiratory failure. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Two-hundred and twenty-patients were enrolled. Mortality rates at 30-day, 90-days, and 1-year follow-up were 20%, 26%, and 34%. When excluding patients with "do-not-resuscitate" status, mortality rates were 13%, 19%, and 28%. The multivariate analyses identified solid cancer, pneumonia in hematologic patients, and do-not-resuscitate status as independent predictors of mortality with postoperative acute respiratory failure associated with improved survival. The same predictors were confirmed when excluding do-not-resuscitate patients from the analyses. CONCLUSIONS: Noninvasive ventilation applied in ordinary wards was effective, with long-term outcomes not different from those reported for ICU settings. Solid cancer, pneumonia in hematologic malignancies, and do-not-resuscitate status predicted mortality, whereas patients with postoperative acute respiratory failure had the best survival rate. Additional studies are required to evaluate noninvasive ventilation efficacy in the wards compared with ICU.

Mortality in Multicenter Critical Care Trials: An Analysis of Interventions With a Significant Effect.

OBJECTIVES: We aimed to identify all treatments that affect mortality in adult critically ill patients in multicenter randomized controlled trials. We also evaluated the methodological aspects of these studies, and we surveyed clinicians' opinion and usual practice for the selected interventions. DATA SOURCES: MEDLINE/PubMed, Scopus, and Embase were searched. Further articles were suggested for inclusion from experts and cross-check of references. STUDY SELECTION: We selected the articles that fulfilled the following criteria: publication in a peer-reviewed journal; multicenter randomized controlled trial design; dealing with nonsurgical interventions in adult critically ill patients; and statistically significant effect in unadjusted landmark mortality. A consensus conference assessed all interventions and excluded those with lack of reproducibility, lack of generalizability, high probability of type I error, major baseline imbalances between intervention and control groups, major design flaws, contradiction by subsequent larger higher quality trials, modified intention to treat analysis, effect found only after adjustments, and lack of biological plausibility. DATA EXTRACTION: For all selected studies, we recorded the intervention and its comparator, the setting, the sample size, whether enrollment was completed or interrupted, the presence of blinding, the effect size, and the duration of follow-up. DATA SYNTHESIS: We found 15 interventions that affected mortality in 24 multicenter randomized controlled trials. Median sample size was small (199 patients) as was median centers number (10). Blinded trials enrolled significantly more patients and involved more centers. Multicenter randomized controlled trials showing harm also involved significantly more centers and more patients (p = 0.016 and p = 0.04, respectively). Five hundred fifty-five clinicians from 61 countries showed variable agreement on perceived validity of such interventions. CONCLUSIONS: We identified 15 treatments that decreased/increased mortality in critically ill patients in 24 multicenter randomized controlled trials. However, design affected trial size and larger trials were more likely to show harm. Finally, clinicians view of such trials and their translation into practice varied.