FACTORS INFLUENCING DEEP-VEIN THROMBOSIS FOLLOWING TOTAL HIP-ARTHROPLASTY UNDER EPIDURAL-ANESTHESIA

To determine intraoperative factors which may influence deep vein thro mbosis rate, we studied surgeries performed by one surgeon on 441 cons ecutive patients undergoing primary total hip arthroplasty under epidu ral anesthesia. Operative limb venography was performed on the fourth or fifth postoperative day in 381 patients, who received 650 mg of asp irin daily as the only postoperative thromboprophylaxis. Of 381 (15%) patients, 58 had a positive venogram; 13 (3%) had proximal thrombi. Of 178 patients (9.5%) with surgery lasting less than 70 min, 17 develop ed deep vein thrombosis whereas 41 of 203 patients (20.3%) with surger y lasting more than 70 n-dn developed deep vein thrombosis (P < 0.05). Corresponding proximal deep vein thrombosis rates increased from 1.7% to 4.9%. Deep vein thrombosis was observed in 12.5% of patients recei ving intravenous low-dose epinephrine, 10.3% receiving intravenous sod ium nitroprusside, 14.5% receiving both low-dose epinephrine and sodiu m nitroprusside concurrently, and 25% receiving intravenous fluid alon e. Proximal deep vein thrombosis rates were 2.4% 0%, 1.45%, and 9.3% i n these groups, respectively. These data suggest that the intraoperati ve management of both surgery and anesthesia influence rates of deep v ein thrombosis following total hip arthroplasty.