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@#BACKGROUND: Peripheral venous pressure (PVP) has been shown to correlate with central venous pressure (CVP) in a number of reports. Few studies, however, have explored the relationship between tissue pressure (TP) and PVP/CVP correlation. METHODS: PVP and CVP were simultaneously recorded in a bench-top model of the venous circulation of the upper limb and in a single human volunteer after undergoing graded manipulation of tissue pressure surrounding the intervening venous conduit. Measures of correlation were determined below and above a point wherein absolute CVP exceeded TP. RESULTS: Greater correlation was observed between PVP and CVP when CVP exceeded TP in both models. Linear regression slope was 0.975 (95％ CI: 0.959-0.990); r20.998 above tissue pressure 10 cmH2O vs. 0.393 (95％ CI: 0.360-0.426); and r20.972 below 10 cmH2O at a flow rate of 2000 mL/h in the in vitro model. Linear regression slope was 0.839 (95％ CI: 0.754-0.925); r20.933 above tissue pressure 10 mmHg vs. slope 0.238 (95％ CI: ?0.052-0.528); and r20.276 in the en vivo model. CONCLUSION: PVP more accurately reflects CVP when absolute CVP values exceed tissue pressure.
RESUMEN
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.