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

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)]. 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. 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˙O2\,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