[A clinical study of diaphragmatic dysfunction in subjects with mechanical ventilation in sepsis]

Objective: To investigate the prevalence of diaphragmatic dysfunction in mechanical ventilated subjects with sepsis and the relationship between diaphragmatic dysfunction and clinical outcomes. Methods: Newly intubated patients with sepsis diagnosed according to "Sepsis-3" were enrolled from January 2017 to October 2017 in Intensive Care Unit (ICU) of Sir Run Run Shaw Hospital. Diaphragm thickness was recorded ultrasonographically at end-inspiration and end-expiration when the patients' spontaneous breathing recovered. The diaphragmatic thickening fraction (DTF) was calculated as the percentage from the following formula: (Thickness at end-inspiration-Thickness at end-expiration) / Thickness at end-expiration. The subjects were stratified into a diaphragmatic dysfunction group and a non-diaphragmatic dysfunction group based on whether DTF was < 20%. Results: Fifty-three subjects were included, and the prevalence of diaphragmatic dysfunction was 41.5%(22/53). The diaphragm thickness at end-expiration of the 2 groups were similar(t=1.328, P>0.05). A significant difference of diaphragm thickness at end-inpiration was observed between the 2 groups[(2.2±0.4)mm vs. (2.8±0.8)mm, t=3.677, P<0.05]. Ventilation time after inclusion [(10±8)d vs. (6±5)d, t=2.340, P<0.05], mechanical ventilation durations [(15±8)d vs. (11±6)d, t=2.201, P<0.05] and ICU length of stay [(18±8)d vs. (14±7)d, t=2.039, P<0.05]were all significantly longer in the diaphragmatic dysfunction group than in the non-diaphragmatic dysfunction group. There was no significant difference in the mortality between these 2 groups(χ(2)=0.366, P>0.05). Conclusions: Diaphragmatic dysfunction was common in patients with sepsis treated by mechanical ventilation and was the consequence of contractile force damages. Subjects with such diaphragmatic dysfunction showed longer mechanical ventilation durations and ICU stays.