Association of protein intake with the outcomes of critically ill patients: a post hoc analysis of the PermiT trial.

Background: The optimal amount of protein intake in critically ill patients is uncertain. Objective: In this post hoc analysis of the PermiT (Permissive Underfeeding vs. Target Enteral Feeding in Adult Critically Ill Patients) trial, we tested the hypothesis that higher total protein intake was associated with lower 90-d mortality and improved protein biomarkers in critically ill patients. Design: In this post hoc analysis of the PermiT trial, we included patients who received enteral feeding for ≥3 consecutive days. Using the median protein intake of the cohort as a cutoff, patients were categorized into 2 groups: a higher-protein group (>0.80 g · kg-1 · d-1) and a lower-protein group (≤0.80 g · kg-1 · d-1). We developed a propensity score for receiving higher protein. Primary outcome was 90-d mortality. We also compared serial values of prealbumin, transferrin, 24-h urinary nitrogen, and 24-h nitrogen balance on days 1, 7, and 14. Results: Among the 729 patients included in this analysis, the average protein intake was 0.8 ± 0.3 g · kg-1 · d-1 [1.0 ± 0.2 g · kg-1 · d-1 in the higher-protein group (n = 365) and 0.6 ± 0.2 g · kg-1 · d-1 in the lower-protein group (n = 364); P < 0.0001]. There was no difference in 90-d mortality between the 2 groups [88/364 (24.2%) compared with 94/363 (25.9%), propensity score-adjusted OR: 0.80; 95% CI: 0.56, 1.16; P = 0.24]. Higher protein intake was associated with an increase in 24-h urea nitrogen excretion compared with lower protein intake, but without a significant change in prealbumin, transferrin, or 24-h nitrogen balance. Conclusions: In the PermiT trial, a moderate difference in protein intake was not associated with lower mortality. Higher protein intake was associated with increased nitrogen excretion in the urine without a corresponding change in prealbumin, transferrin, or nitrogen balance. Protein intake needs to be tested in adequately powered randomized controlled trials targeting larger differences in protein intake in high-risk populations.

The diagnostic yield and clinical impact of a chest X-ray after percutaneous dilatational tracheostomy: a prospective cohort study.

A chest X-ray (CXR) is routinely performed after percutaneous dilatational tracheostomy (PDT). The purpose of this study was to evaluate the diagnostic yield of routine CXR following PDT and its impact on patient management and to identify predictors of post-PDT CXR changes. Two-hundred-and-thirty-nine patients who underwent PDT in a 21-bed intensive care unit were included prospectively in the study. The following data were collected: patient demographics, APACHE III scores, pre-PDT FiO2 and PEEP, PDT technique, perioperative complications and the use of bronchoscopic guidance. We compared post-PDT CXR with the last pre-PDT CXR. We documented any post-PDT new radiographic findings including atelectasis, pneumothorax, pneumomediastinum, surgical emphysema, pulmonary infiltrates or tracheostomy tube malposition. We also recorded management modifications based on post-PDT radiographic changes, including increased PEEP, chest physiotherapy, therapeutic bronchoscopy or chest tube insertion. Atelectasis was the only new finding detected on post-PDT CXRs of 24 (10%) patients. The new radiographic findings resulted in a total of 14 modifications of management in 10 (4%) patients including increased PEEP in six, chest physiotherapy in six and bronchoscopy in two patients. Trauma and pre-PDT PEEP >5 cmH2O were independent predictors of post-PDT CXR changes. Routine CXR following PDT has a low diagnostic yield, detecting mainly atelectasis and leading to a change in the management in only a minority ofpatients. Routine CXR after apparently uncomplicated PDT performed by an experienced operator may not be necessary and selective use may improve its diagnostic yield. Further studies are required to validate the safety of selective versus routine post-PDT CXR.