Role of cardiopulmonary exercise testing as a risk-assessment method in patients undergoing intra-abdominal surgery: a systematic review

Abstract Background Cardiopulmonary exercise testing (CPET) is used as a preoperative risk-stratification tool for patients undergoing non-cardiopulmonary intra-abdominal surgery. Previous studies indicate that CPET may be beneficial, but research is needed to quantify CPET values protective against poor postoperative outcome [mortality, morbidity, and length of stay (LOS)]. Methods This systematic review aimed to assess the ability of CPET to predict postoperative outcome. The following databases were searched: PubMed, EMBASE, PEDro, The Cochrane Library, Cinahl, and AMED. Thirty-seven full-text articles were included. Data extraction included the following: author, patient characteristics, setting, surgery type, postoperative outcome measure, and CPET outcomes. Results Surgeries reviewed were hepatic transplant and resection ( n +7), abdominal aortic aneurysm (AAA) repair ( n +5), colorectal ( n +6), pancreatic ( n +4), renal transplant ( n +2), upper gastrointestinal ( n +4), bariatric ( n +2), and general intra-abdominal surgery ( n +12). Cardiopulmonary exercise testing-derived cut-points, peak oxygen consumption ( V ˙ O 2 \,peak ), and anaerobic threshold (AT) predicted the following postoperative outcomes: 90 day–3 yr survival (AT 9–11 ml kg −1 min −1 ) and intensive care unit admission (AT −1 min −1 ) after hepatic transplant and resection, 90 day survival after AAA repair ( V ˙ O 2 \,peak 15 ml kg −1 min −1 ), LOS and morbidity after pancreatic surgery (AT −1 min −1 ), and mortality and morbidity after intra-abdominal surgery (AT 10.9 and −1 min −1 , respectively). Conclusion Cardiopulmonary exercise testing is a useful preoperative risk-stratification tool that can predict postoperative outcome. Further research is needed to justify the ability of CPET to predict postoperative outcome in renal transplant, colorectal, upper gastrointestinal, and bariatric surgery.