Temporal trends in prevention of venous thromboembolism following primary total hip or knee arthroplasty 1996-2001: findings from the Hip and Knee Registry.

BACKGROUND The Hip and Knee Registry is an observational database comprising data on practices of US orthopedic surgeons during 1996 to 2001. We examined trends in the use of prophylaxis for venous thromboembolism (VTE) among patients who underwent primary total hip arthroplasty (THA) or total knee arthroplasty (TKA). METHODS Data on 9,327 THA and 13,846 TKA patients were submitted between 1996 and 2001 by 464 orthopedic surgeons from 319 hospitals in 42 of the United States. RESULTS During 1996 to 2001, 44% of THA patients and 38% of TKA patients were male, and 93% and 92% were white, respectively. The median age of THA and TKA patients increased from 66 to 68 years and 68 to 69 years, respectively, between 1996 and 2001 (p < 0.001), while the mean length of hospital stay decreased from 4.7 to 3.7 days and 4.5 to 3.7 days, respectively (p < 0.001). Use of spinal or epidural anesthesia increased from 34 to 46% for THA and 43 to 54% for TKA patients (p < 0.001). One or more types of thromboprophylaxis were administered to 99% of patients. The following were the most common types of thromboprophylaxis: elastic stockings (61% and 58%), warfarin (56% and 53%), low-molecular-weight heparin (38% and 40%), and intermittent pneumatic compression (35% and 32%) in THA and TKA patients, respectively. Aspirin was used for thromboprophylaxis in 4% of THA and 7% of TKA patients. One or more type of in-hospital prophylaxis matching the 2001 American College of Chest Physicians (ACCP) recommendations were administered to 89% of THA and 91% of TKA patients between 1996 and 2001. During this period, in-hospital use of ACCP prophylaxis recommendations increased from 88 to 94% following THA (p < 0.001). This increase was also observed for prophylaxis administered to TKA patients, although this did not reach statistical significance. CONCLUSIONS Recent trends in the management of patients undergoing THA and TKA in the United States, including shorter lengths of hospital stay and increased use of spinal/epidural anesthesia, present a challenge to orthopedic surgeons who wish to provide their patients with effective prophylaxis for VTE. Despite these challenges, nearly all surgeons participating in the Hip and Knee Registry are providing types of prophylaxis consistent with evidence-based consensus recommendations. Although there are concerns regarding increased bleeding risk due to the use of anticoagulants in patients receiving spinal/epidural anesthesia, there was a significant increase in the use of spinal/epidural anesthesia between 1996 and 2001. During this same period, the proportion of patients receiving spinal/epidural anesthesia who were also administered anticoagulants as prophylaxis increased significantly.