Perioperative pulmonary circulatory changes during bilateral total hip arthroplasty under regional anesthesia.

Background and Objectives—The transient and rarely clinically relevant effect of bone and cement embolization during unilateral joint arthroplasty is a known phenomenon. However, available studies do not address events surrounding bilateral total hip arthroplasties, during which embolic load is presumably doubled. To elucidate events surrounding this increasingly utilized procedure and assess the effect on the pulmonary hemodynamics in the intra- and postoperative period, we studied 24 subjects undergoing cemented bilateral total hip arthroplasty during the same anesthetic session. Materials—Twenty four patients without previous pulmonary history undergoing cemented bilateral total hip arthroplasty under controlled epidural hypotension were enrolled. Pulmonary artery catheters were inserted and hemodynamic variables were recorded at baseline, 5 minutes after the implantation of each hip joint, 1 hour and 1 day postoperatively. Mixed venous blood gases and complete blood counts were analyzed at every time point. Results—An increase in pulmonary vascular resistance was observed after the second but not the first hip implantation when compared to values at incision. Pulmonary vascular resistance remained elevated 1 hour postoperatively. Pulmonary artery pressures were significantly elevated on post operative day 1 compared to baseline values. The white blood cell count increased in response to the second hip implantation but not the first compared to incision. Conclusion—The embolization of material during bilateral total hip arthroplasty is associated with prolonged increases in pulmonary artery pressures and vascular resistance, particularly after the second side. The performance of bilateral procedures should be cautiously considered in patients with diseases suggesting decreased right ventricular reserve.