# The effects of continuing aspirin and clopidogrel on perioperative outcomes in primary elective total knee and hip replacement: A systematic review and meta-analysis

## TL;DR

This study reviews the effects of continuing aspirin or clopidogrel during hip and knee replacement surgeries and finds that it increases blood transfusion risk in knee replacements but not hip replacements.

## Contribution

The study provides a meta-analysis of perioperative outcomes for continuing antiplatelet therapy in total hip and knee replacements.

## Key findings

- Continuing antiplatelet therapy did not affect intraoperative blood loss in THR or TKR.
- TKR patients on antiplatelets had a higher risk of blood transfusion.
- No significant differences were found in infection, cardiac events, or mortality between groups.

## Abstract

Approximately 20 % of patients undergoing primary elective total hip (THR) or knee replacement (TKR) take an antiplatelet medication. The two main management strategies are continuing or discontinuing the antiplatelet medication pre-operatively. Continuing antiplatelets may increase the risk of bleeding, wound complications, and infection. Discontinuing antiplatelets may increase the risk of cardiac and cerebrovascular adverse events. This systematic review and meta-analysis evaluated the effects of continuing aspirin or clopidogrel on the perioperative outcomes of patients undergoing THR or TKR.

Medline, Embase, Web of Science, and Cochrane Library were searched for randomised controlled trials and cohort studies reporting on outcomes blood loss, infection, wound complications, operative duration, length of stay, venous thromboembolism, cardiac and cerebrovascular events, mortality, and others. Random effects meta-analysis was performed.

Eight studies enabled inclusion of data on 928 THRs and 3526 TKRs. Continuing antiplatelet therapy did not affect intraoperative blood loss in THR (MD -16.57 ml, 95 % CI -120.75–87.61, p = 0.76) or TKR (MD -0.06 ml, 95 %CI -6.04–5.91, p = 0.98). However, TKR patients continuing antiplatelet therapy had a higher risk of blood transfusion (OR 1.63, 95 %CI 1.25–2.13, p = 0.0003) although there were no differences observed in THR patients (OR 1.71, 95 %CI 0.84–3.49, p = 0.14). No significant differences were found for outcomes infection, cardiac and cerebrovascular events, and post-operative mortality between patient groups following THR and TKR.

Continuing antiplatelet use during TKR, but not THR, was associated with an increased risk of blood transfusion. Surgical complications and medical adverse events were not influenced by antiplatelet use. Further research with larger sample sizes is needed to draw definitive conclusions.

PROSPERO (CRD42024470601)