Prevalence and time-course of diaphragmatic dysfunction following lung resection: A repeated ultrasonic assessment.

ABSTRACT

PURPOSE: Ultrasound (US) allows non-invasive repeated assessments of diaphragmatic excursion (DE) and thickening fraction (DTF) at the bedside, reflecting diaphragmatic dysfunction (DD). We aimed at determining the prevalence and time-course of DD following elective thoracic surgery and the association with postoperative complications. MATERIAL AND METHODS: Prospective, single-centre, observational study with consecutive patients undergoing thoracic surgery. DE/DTF were measured by two observers blinded to each other at 3 different time-points prior to surgery, immediately after extubation and on postoperative day 3. The changes in DE/DTF of both hemi-diaphragms over time were compared according to the side (operated/non-operated) using a two-way-ANOVA. The association with postoperative complications was assessed using logistic regression. RESULTS: Fifty patients, 60% males, aged 60 ± 15 years were included. Surgical procedures included lobectomy (n = 30), wedge-resection (n = 17) or pneumonectomy (n = 3). On the operated side, we observed a decrease in DE/DTF at D0 (-0.71 ± 0.12 mm, P < 0.05; -44 ± 30%, P < 0.05) and D3 (-0.82 ± 0.19 mm, P < 0.05; -39 ± 19%, P < 0.05) with respect to preoperative and non-operated side values over the study period. Persistent DD on the operated side was associated with an increased risk of lung infection (OR 9.0, 95% CI [1.92-65.93], P = 0.001), ICU-admission (OR 3.9, 95% CI [1.10-15.53], P = 0.04) according to univariate analysis and a prolonged length in hospital (OR 1.3, 95% CI [1.1-1.7], P = 0.016) according to multivariate analysis. CONCLUSIONS: Thoracic surgery generates DD mainly observed on the operated side, which persists at least up to postoperative D3 and is associated with an increase in hospital stay.