Could the loss of diaphragm thickness measured by computer tomography predict the rate of reintubation?

Abstract

Background: Diaphragm function loss is very common in the intensive care unit (ICU) and can predict the success of weaning. However, whether diaphragm thickness loss during mechanical ventilation (MV) as measured by computed tomography (CT) can predict the rate of reintubation remains unclear. Therefore, we hypothesized that a loss of diaphragm thickness would impact the outcome of weaning. Methods: A retrospective study was performed on patients who received MV in the ICU of West China Hospital, Sichuan University. The diaphragm thickness of each patient on the CT scans within 48 hours after MV and 24 hours before weaning were measured by at least two independent investigators. The primary outcome was the rate of reintubation, and the second outcomes included hospital mortality and the length of ICU stay (ICU LOS) after extubation. Results: A total of 145 patients were included in the analysis. According to the receiver operating characteristic curve, all patients were divided into two groups (less or more than 1.55 mm diaphragm thickness loss in reintubation). As a result, less loss of diaphragm thickness was a protective factor for the rate of reintubation [33% vs. 12%; adjusted odds ratio (aOR) 0.001; 95% confidence interval (CI), 0.001–0.271; P=0.018] and hospital mortality (18% vs. 4%; aOR 0.001; 95% CI, 0.001–0.035; P=0.007). However, no significant difference was found in the ICU LOS after extubation between the two groups. Conclusions: Less diaphragm thickness loss was related to a lower rate of reintubation and hospital mortality.