Effect of positive end-expiratory pressure on the central venous pressure of patients with different respiratory system compliance

Abstract

Objective To investigate the effect of positive end-expiratory pressure on the central venous pressure in patients with different respiratory system compliance. Methods In this prospective study, 55 patients under mechanical ventilation and CVP monitoring were enrolled. According to the respiratory system static compliance(Crs), the patients were divided into high compliance group [Crs≥0.63 ml/(cmH2O•kg)] and low compliance group [Crs<0.63 ml/(cmH2O•kg)]. The value of CVP, heart rate, blood pressure and respiratory mechanics were recorded at a PEEP level of 5, 10, 15 cmH2O respectively. Results CVP elevated with PEEP increased in both high compliance and low compliance groups (P<0.05); In patients with high compliance, the CVP was (8.4±2.7), (10.3±2.5), (12.2±2.5) cmH2O at a PEEP level of 5, 10, 15 cmH2O (P<0.05). Similarly, CVP was (9.6±2.9), (11.0±2.8), (12.2±2.7) cmH2O at a PEEP level of 5, 10, 15 cmH2O (P<0.05) respectively in patients with low compliance. With PEEP increased, CVP in the high compliance group increased more significantly compared to patients with low compliance (P<0.05). Conclusion For patients receiving mechanical ventilation, the CVP value was affected by the increase of PEEP especially in patients with high respiratory compliance. Key words: Positive end-expiratory pressure; Central venous pressure; Mechanical ventilation; Respiratory system compliance