Risk factor assessment in 101 total hip arthroplasties: a medical perspective.

: Our experience with 101 consecutive T.H.A.'s in 91 patients was examined in an attempt to identify preoperative risk factors for postoperative medical complications, especially pulmonary embolism and thrombophlebitis. Six per cent of patients developed postoperative clinical thrombophlebitis, and 8% a pulmonary embolism. Advancing age and previous venous thrombosis served as predictors for pulmonary embolism and thrombophlebitis, respectively (p less than 0.01), but obesity, venous varicosities, diabetes mellitus, cigarette smoking, previous pulmonary embolism, and length of surgery did not, for either. Fifty per cent of the patients with preoperative abnormal kidney function developed some form of medical complication postoperatively, a significant increase in risk (p less than 0.05) over patients with normal kidney function. We were unable to identify an increase in postoperative atelectasis or pneumonia associated with smoking or obesity in these patients. No consistent decrease in post-operative medical morbidity could be assigned to preoperative medical consultations, suggesting that we have not yet identified all significant risk factors. A thorough preoperative preparation and improvement in intra- and postoperative techniques and management may account for differences found in this study from traditionally held risk factors.