Background: Aerobic exercise is a critical component of cardiac rehabilitation following cardiac surgery. Aerobic exercise is traditionally commenced 2-6 weeks following hospital discharge and most commonly includes stationary cycling or treadmill walking. The initiation of aerobic exercise within this early postoperative period not only introduces the benefits associated with aerobic activity sooner, but also ameliorates the negative effects of immobilization associated with the early postoperative period.
Methods: A systematic review identified all studies reporting safety and efficacy outcomes of aerobic exercise commenced within two weeks of cardiac surgery. A meta-analysis was performed comparing functional, aerobic and safety outcomes in patients receiving early postoperative aerobic exercise compared with usual postoperative care.
Results: Six-minute walk test distance at hospital discharge was 419 ± 88 m in early aerobic exercise patients versus 341 ± 81 m in those receiving usual care (mean difference 69.5 m, 95% confidence interval (CI) 39.2-99.7 m, p < 0.00001). Peak aerobic power was 18.6 ± 3.8 ml·kg-1·min-1 in those receiving early exercise versus 15.0 ± 2.1 ml·kg-1·min-1 in usual care (mean difference 3.20 ml·kg-1·min-1, 95% CI 1.45-4.95, p = 0.0003). There was no significant difference in adverse events rates between the two groups (odds ratio 0.41, 95% CI 0.12-1.42, p = 0.16).
Conclusion: Aerobic exercise commenced early after cardiac surgery significantly improves functional and aerobic capacity following cardiac surgery. While adverse event rates did not differ significantly, patients included were very low risk. Further studies are required to adequately assess safety outcomes of aerobic exercise commenced early after cardiac surgery.
Keywords: Early rehabilitation; aerobic exercise; cardiac rehabilitation; cardiac surgery; exercise rehabilitation; rehabilitation safety.