Flow triggering added to pressure support ventilation improves comfort andreduces work of breathing in mechanically ventilated patients

Purpose: The purpose of this study was to measure the effect of flow trigge ring (FI), added to pressure support ventilation (PSV), during spontaneous breathing in intubated patients. Materials and Methods: A prospective observational study was conducted at a Comprehensive Cancer Center, University Hospital. Fourteen consecutive cri tically ill, mechanically ventilated patients on PSV with positive end-expi ratory pressure were studied. Flow triggering was added to PSV in spontaneo usly breathing ventilated patients, Results: Respiratory rate (f), minute ventilation (V epsilon), patient work of breathing (WOBp), respiratory drive (P-0.1), rapid shallow breathing in dex (f/V-t), tidal volume (V-t) and a visual analog scare of breathing effo rt and comfort all improved. There was a large decrease in WOBP and P-0.1 w hen flow triggering was added to PSV (P < .001). There was a moderate decre ase in f/V-t during the same procedure (P < .01), Twelve patients felt subj ectively better with the intervention. Conclusions: Flow triggering offers an excellent complement to PSV because it improves patient comfort and reduces the magnitude of the inspiratory ef fort as well as the delay time between inspiratory muscle contraction and g as flow. it augments gas exchange at no metabolic cost to the patient while reducing the work of breathing, Copyright (C) 1999 by W.B. Saunders Compan y.