Pulmonary Artery versus Central Venous Catheter Monitoring in the Outcome of Patients Undergoing Bilateral Total Knee Replacement

Abstract

Bilateral total knee replacement (BTKR) has been associated with a higher incidence of fat embolism (FES) compared to single knee replacement. Consequently, intraoperative monitoring with a pulmonary artery catheter (PAC) has been recommended. This study compares clinical outcome in BTKR patients monitored with central venous pressure versus PAC. A retrospective chart review of 249 consecutive patients undergoing BTKR, 132 of whom had PAC insertion versus 117 who had central line insertion, over a 1-year period were included in the study. Their medical records were reviewed for co-morbidities, baseline characteristics, and type of intraoperative monitoring. Need and duration for postoperative monitoring in the postoperative care, length of hospital stay (LOHS), signs of fat embolism, development of arrhythmias, and respiratory failure were all outcome measures. A total of four patients (1.6%) had FES as per Schonfeld criteria. One of these patients died within 48 h of surgery. They all had PAC monitoring intraoperatively. Pulmonary artery pressure (PAP) remained unchanged during surgery which raises doubt as to the clinical utility and advisability of the use of PAC's in this setting. There was no statistically significant difference in cardiac or pulmonary complications, or LOHS between the two groups. Central venous pressure monitoring appears to be sufficient in patients undergoing BTKR.