BACKGROUND: Peripheral venous pressure (PVP) was known to have significant correlation with central venous pressure (CVP) in patients with normal and abnormal cardiac function. The purpose of this study is to evaluate the possibility of PVP as a substitute of CVP for volume status monitoring.
METHODS: 41 hypovolemic patients with pulmonary capillary wedge pressure (PCWP) below 10 mmHg, scheduled for elective coronary artery bypass graft were included. CVP and PVP were measured from proximal port of pulmonary artery (PA) catheter and antecubital vein, respectively. Each was connected to the same monitoring system by rigid tubes of same length. Measurements were performed as follows: after PA catheter insertion; after increasing PCWP above 10 mmHg by I.V. fluid infusion; and after anesthesia induction. Hemodynamic variables were recorded at end-expiration after stabilizing for 5 10 minutes. For statistical analysis, Bland and Altman plot was created.
RESULTS: The overall mean bias between CVP and PVP was 0.7 mmHg (95% confidence interval, 1 0.5). Limits of agreement of mean bias was 2.1 3.6 mmHg. 118 out of 121 PVP measurements were within the ranges of CVP ± 3 mmHg (98%). The direction of CVP change was predicted by PVP in 68%. However, larger changes of PVP (≥ or = 2 mmHg) predicted the changes of CVP with increased accuracy (90%). There were only 5 cases that CVP and PVP had changed in opposite direction.
CONCLUSIONS: In conclusion, PVP has a potential to be a substitutional hemodynamic parameter of CVP.