Abstract
IntroductionDyspnea is common and often severe symptom in mechanically ventilated patients. Proportional assist ventilation (PAV) is an assist ventilatory mode that adjusts the level of assistance to the activity of respiratory muscles. We hypothesized that PAV reduce dyspnea compared to pressure support ventilation (PSV).Patients and methodsMechanically ventilated patients with clinically significant dyspnea were included. Dyspnea intensity was assessed by the Dyspnea—Visual Analog Scale (D-VAS) and the Intensive Care-Respiratory Distress Observation Scale (IC-RDOS) at inclusion (PSV-Baseline), after personalization of ventilator settings in order to minimize dyspnea (PSV-Personalization), and after switch to PAV. Respiratory drive was assessed by record of electromyographic activity of inspiratory muscles, the proportion of asynchrony was analyzed.ResultsThirty-four patients were included (73% males, median age of 66 [57–77] years). The D-VAS score was lower with PSV-Personalization (37 mm [20‒55]) and PAV (31 mm [14‒45]) than with PSV-Baseline (62 mm [28‒76]) (p < 0.05). The IC-RDOS score was lower with PAV (4.2 [2.4‒4.7]) and PSV-Personalization (4.4 [2.4‒4.9]) than with PSV-Baseline (4.8 [4.1‒6.5]) (p < 0.05). The electromyographic activity of parasternal intercostal muscles was lower with PAV and PSV-Personalization than with PSV-Baseline. The asynchrony index was lower with PAV (0% [0‒0.55]) than with PSV-Baseline and PSV-Personalization (0.68% [0‒2.28] and 0.60% [0.31‒1.41], respectively) (p < 0.05).ConclusionIn mechanically ventilated patients exhibiting clinically significant dyspnea with PSV, personalization of PSV settings and PAV results in not different decreased dyspnea and activity of muscles to a similar degree, even though PAV was able to reduce asynchrony more effectively.
Highlights
Dyspnea is common and often severe symptom in mechanically ventilated patients
The Dyspnea—Visual Analog Scale (D-VAS) score was lower with pressure support ventilation (PSV)-Personalization (37 mm [20‒55]) and Proportional assist ventilation (PAV) (31 mm [14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45]) than with PSV-Baseline (62 mm [28‒76]) (p < 0.05)
The Intensive Care Respiratory Distress Observation Scale (IC-RDOS) score was lower with PAV (4.2 [2.4‒4.7]) and PSV-Personalization (4.4 [2.4‒4.9]) than with PSV-Baseline (4.8 [4.1‒6.5]) (p < 0.05)
Summary
Dyspnea is common and often severe symptom in mechanically ventilated patients. Proportional assist ventilation (PAV) is an assist ventilatory mode that adjusts the level of assistance to the activity of respiratory muscles. Dyspnea in mechanically ventilated patients is partly due to a mismatch between the patient’s inspiratory effort and the level of assistance, corresponding to underassistance [2] This mismatch may generate patient– ventilator asynchrony, which is associated with poorer clinical outcomes [4]. A mismatch between the patient’s inspiratory effort and the level of Bureau et al Annals of Intensive Care (2021) 11:177 assistance is likely to occur [2, 5,6,7,8,9,10,11] Ventilator settings such as the assist control mode and a low pressure support level are associated with increased dyspnea [2, 12]. Few data are currently available concerning the impact of PAV + on dyspnea, as most studies have been conducted in healthy subjects or ICU patients without clinically significant dyspnea [13,14,15,16,17, 19,20,21]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
