Cardiology · Medical Literature
Effect of Buerger-Allen Exercises on Lower Extremity Perfusion in Diabetes Mellitus Patients Undergoing Coronary Artery Bypass Grafting With Saphenous Vein Harvesting: A Randomized Controlled Trial.
Abstract
Patients with diabetes mellitus undergoing coronary artery bypass grafting (CABG) with saphenous vein harvesting are at increased risk of impaired lower extremity perfusion and wound-related complications. Buerger-Allen exercises have been proposed to improve peripheral circulation; however, evidence supporting their effectiveness following CABG remains limited. This study evaluated the effect of Buerger-Allen exercises as an adjunct to phase I cardiac rehabilitation on lower extremity perfusion and wound healing in diabetic patients undergoing CABG. A randomized controlled trial was conducted involving 60 diabetic patients undergoing CABG with saphenous vein harvesting. Participants were randomly allocated to an intervention group receiving standard phase I cardiac rehabilitation plus Buerger-Allen exercises (n = 30) or a control group receiving standard rehabilitation alone (n = 30). The primary outcome was ankle-brachial index (ABI). Secondary outcomes included wound healing disturbances and peripheral ankle swelling. Postoperative ABI was analyzed using two-way repeated-measures ANOVA, whereas categorical outcomes were analyzed using Fisher's exact test or the Chi-squared test. A significant effect of time on ABI was observed (p = 0.004), whereas neither the group effect (p = 0.754) nor the group × time interaction (p = 0.711) was statistically significant. An earlier resolution of mild wound-related pain was observed on postoperative day 3 in the intervention group (p = 0.038); however, no between-group differences were present on postoperative day 5. No intervention-related adverse events were reported. Buerger-Allen exercises were safe and feasible during early postoperative rehabilitation but did not provide additional improvement in lower extremity perfusion beyond standard rehabilitation during the 5-day postoperative period. The isolated improvement in wound-related pain should be interpreted cautiously. Buerger-Allen exercises did not significantly improve the primary outcome of lower extremity perfusion following CABG. Although they appeared safe and were associated with transient improvement in wound-related pain, further adequately powered studies with longer follow-up are required to determine whether clinically meaningful benefits exist. This study was prospectively registered in the Clinical Trial Registry India (CTRI/2023/10/058535).
Clinical relevance
Diabetic patients undergoing CABG with saphenous vein harvesting represent a high-risk population for impaired lower extremity perfusion and wound-related complications, yet evidence-based adjunctive rehabilitation strategies for this subgroup remain scarce. Buerger-Allen exercises, a gravity-dependent positional exercise protocol designed to enhance peripheral circulation, have been proposed but lack rigorous evaluation in the post-CABG context. This RCT directly addresses that evidence gap, providing timely data to inform phase I cardiac rehabilitation protocols in diabetic surgical patients.
Key findings
1. Primary outcome — Ankle-Brachial Index (ABI): A significant effect of time on ABI was observed across both groups (p = 0.004), indicating postoperative ABI changes over the 5-day period; however, neither the group effect (p = 0.754) nor the group × time interaction (p = 0.711) reached statistical significance, meaning Buerger-Allen exercises did not produce superior ABI improvement over standard rehabilitation alone. 2. Sample and design: 60 diabetic CABG patients with saphenous vein harvesting were randomized 1:1 — intervention group (n = 30) received standard phase I cardiac rehabilitation plus Buerger-Allen exercises; control group (n = 30) received standard rehabilitation alone. 3. Wound-related pain (secondary outcome): A statistically significant earlier resolution of mild wound-related pain was observed on postoperative day 3 in the intervention group (p = 0.038); this between-group difference was no longer present by postoperative day 5, indicating a transient rather than sustained effect. 4. Peripheral ankle swelling (secondary outcome): No between-group differences in peripheral ankle swelling were reported across the postoperative assessment period. 5. Safety and feasibility: No intervention-related adverse events were reported in either group, supporting the safety and feasibility of Buerger-Allen exercises during the early postoperative inpatient phase. 6. Statistical methodology: Postoperative ABI was analyzed using two-way repeated-measures ANOVA; categorical outcomes (wound healing disturbances, swelling) were analyzed using Fisher's exact test or the Chi-squared test. The study was prospectively registered (CTRI/2023/10/058535); NNT/NNH and confidence intervals were not reported in the abstract.
Practice implications
Buerger-Allen exercises should not be routinely added to standard phase I cardiac rehabilitation protocols in diabetic post-CABG patients with the expectation of meaningfully improving lower extremity perfusion or reducing wound complications, as no significant benefit over standard care was demonstrated within the 5-day postoperative window. Given their established safety profile and a signal toward transient early wound-pain relief on postoperative day 3, these exercises may still be incorporated as a low-risk adjunct, particularly in patients with symptomatic mild wound discomfort, while clearly communicating to patients that evidence of perfusion benefit is lacking. Future adequately powered RCTs with longer follow-up durations, stratification by peripheral artery disease severity, and objective wound-healing endpoints are needed before any revision of clinical practice guidelines can be justified.