Supervised exercise program improves aerobic fitness in patients awaiting abdominal aortic aneurysm repair

Aerobic fitness is an important predictor of postoperative outcome in major surgery. In this study, we assess the effects of a period of preoperative exercise on aerobic fitness as measured by cardiopulmonary exercise testing (CPET) in patients scheduled for abdominal aortic aneurysm (AAA) repair.

As part of a randomized trial, the first patients recruited in the intervention group were enrolled in a supervised exercise program of six week duration. Treadmill CPET parameters were measured before and after exercise preoperatively for these patients. These parameters were as follows: peak oxygen uptake (VO2 peak), anaerobic threshold (AT), and ventilator equivalents for oxygen and carbon dioxide (VE/VO2 and VE/VCO2, respectively). Total exercise time and the time at which AT was achieved were also recorded. A comparison between pre- and postexercise parameters was made to detect for a possible improvement in aerobic fitness.

Twenty patients with AAA (17 men; mean age: 74.9 ± 5.9 years) were included in this study. Thirty-five percent of patients had a history of ischemic heart disease, 25% of obstructive airway disease, and 15% of cerebral vascular events. Seventy percent were previous smokers, and 15% were current smokers. Fifty-five percent of patients were taking aspirin and 75% were undergoing statin therapy. The median (interquartile range) VO2 peak at baseline was 18.2 (15.4-19.9) mL/kg/min, and after exercise was 19.9 (17.1-21.1; P = 0.048). Median AT at baseline was 12.2 (10.5-14.9), and 14.4 (12.3-15.4) after exercise (P = 0.023). Time of exercise tolerated also improved from a median of 379 to 604 sec (P = 0.001). No significant changes were seen in VE/VO2, VE/VCO2, or the time at which AT was achieved.

This study shows that cardiopulmonary aerobic fitness improves after a period of supervised exercise in patients scheduled for AAA repair. This is justification for a randomized trial to assess whether this affects morbidity and mortality after AAA repair.