2006 Abstract : 1- 13

Authors: Javad Parvizi, MD*; Elie Ghanem, MD; Peter F Sharkey, MD; Richard H Rothman, MD; William Hozack, MD

Title: Does Excessive Anticoagulation Predispose The Patient To Periprosthetic Infection?

Addresses: Rothman Institute, 925 Chestnut Street, Philadelphia, Pa 19107

Purpose: Periprosthetic infection (PPI) remains one of most challenging complications of joint replacement. A number of predisposing risk factors for PPI have been identified. The aim of this study is to determine whether postoperative hematoma formation, wound drainage, and excess anticoagulation are predisposing factors for PPI.

Methods: We conducted a 2 to 1 case-control study to determine risk factors for PPI including postoperative INR. 78 cases without prior history of PPI underwent revision for septic failure. The control group consisted of 156 patients who underwent revision procedure for aseptic failure and were followed up for the same period. The two groups were strictly matched for age, sex, surgeon, type of prosthesis, and date of implantation. The anticoagulation protocol was the same throughout the study period. Patient co-morbidities, preoperative medications, intraoperative factors, and postoperative factors were collected and compared between the two groups using univariate and multivariate analysis.

Results: Among the 78 infected cases, 26 patients had developed wound drainage and 11 patients had incisional hematoma necessitating surgical evacuation following the primary procedure. The postoperative INR was higher among the group of patients who later developed PPI. There were only two patients from the control group who developed hematoma and another had post-operative wound drainage. The development of hematoma (p < 0.001), wound drainage (p < 0.001), or both (p < 0.001) was significantly higher in the infected group as compared to the control group respectively.

Discussion: The incidence of postoperative wound drainage and incisional hematoma was significantly higher in patients who later became infected after their primary procedure. The INR of those patients who later developed PPI was higher than their aseptic counterparts. Postoperative hematoma formation and wound drainage are potential risk factors for development of PPI.Cautious anticoagulation to prevent hematoma formation and/or wound drainage is critical to prevent PPI and its devastating complications. Aggressive surgical management of persistent wound drainage and wound hematoma needs to be investigated.