Central venous pressure and ultrasonographic measurement correlation and their associations with intradialytic adverse events in hospitalized patients: A prospective observational study

Purpose: To investigate correlation of central venous pressure (CVP) with ultrasonographic measurement of central veins, along with association between these variables and occurrence of intradialytic adverse events in hospitalized patients.

Materials and methods: Patients requiring hemodialysis via dialysis catheter were prospectively enrolled. CVP measurements through catheter, internal jugular vein aspect ratio, subclavian vein collapsibility, inferior vena cava (IVC) maximal diameter, and IVC collapsibility were recorded before and after hemodialysis. Predictive accuracy of ultrasonographic measurements in discriminating high versus low CVP and their association with intradialytic adverse events were evaluated. Area under receiver operating characteristic curves (AUCs) were calculated.

Results: Fifty-nine patients were enrolled. Median (interquartile range) pre- and post-dialysis CVPs were 8 (4-13)mmHg and 6 (3-10)mmHg, respectively (P<0.01). In pre-dialysis, IVC collapsibility had the highest AUC (0.79, P<0.01) to predict CVP >8mmHg. In post-dialysis, IVC maximal diameter had the highest AUC (0.86, P<0.01) to predict CVP ≤4mmHg. Fifteen patients (25%) had adverse events. Neither pre-dialytic CVP nor ultrasonographic variables were associated with occurrence of adverse events.

Conclusions: Highest accuracy in predicting low and high CVP was observed with ultrasonographic assessment of IVC diameter and collapsibility. Adverse events were not predicted by pre-dialytic CVP or ultrasonographic measurements.