Benchmark residual VTE risks for contemporary prophylaxis proposed
MedWire News: Approximately one in every 100 patients undergoing knee replacement and one in every 200 undergoing hip replacement will develop symptomatic venous thromboembolism (VTE) prior to discharge, even though they receive thromboprophylaxis, researchers report in JAMA.
The findings arise from a systematic review and meta analysis conducted by Jean-Marie Januel (Lausanne University Hospital, Switzerland) and colleagues.
The researchers say that "without prophylaxis, VTE (both symptomatic and asymptomatic) is the most frequent surgical adverse event after infections."
"Yet no estimate of symptomatic VTE risk prior to hospital discharge is available from the literature that can be conveyed to patients in the informed consent process," they add.
The researchers therefore searched contemporary literature (1996-2011) for randomized clinical trials (RCTs) and observational studies that reported rates of in-hospital postoperative symptomatic VTE (pulmonary embolism [PE] or deep vein thrombosis [DVT]) in patients who received recommended VTE prophylaxis after undergoing total or partial knee arthroplasty (TPKA) or total or partial hip arthroplasty (TPHA).
They identified 47 studies (six observational, 41 RCTs) with a total of 44,844 patients (21,369 undergoing TPHA and 23,475 undergoing TPKA). There were 288 cases of symptomatic postoperative VTE in the TPKA patients and 155 in the TPHA patients.
Januel and co-authors report that, in patients undergoing TPKA, the pooled incidence rates of symptomatic VTE, DVT, and PE were 1.09%, 0.63%, and 0.27%, respectively.
The corresponding values in patients undergoing TPHA were 0.53%, 0.26%, and 0.14%.
The researchers suggest that, since VTE rates after TPKA and TPHA are proposed patient safety indicators, these findings could be used as a benchmark to evaluate institutional VTE event rates.
However, in an accompanying editorial, John Heit (Mayo Clinic, Rochester, Minnesota, USA) says that "rates of symptomatic VTE before hospital discharge after THR or TKR may be suboptimal safety indicators, because the period of VTE risk extends beyond the length of hospitalization for surgery."
Therefore, "future efforts should be directed toward enlarging the period of observation to accurately collect VTE outcome events that reflect the entire period of VTE risk after THR and TKR," he concludes.
By Laura Cowen