title: Impaired functional capacity is associated with all-cause mortality after major elective intra-abdominal surgery.
abstract: BACKGROUND
  Studies of preoperative cardiopulmonary exercise testing (CPET) have shown that a reduced oxygen uptake at anaerobic threshold (AT) and elevated ventilatory equivalent for carbon dioxide (VE/VCO(2)) were associated with reduced short- and medium-term survival after major surgery. The aim of this study was to determine the relative values of these, and also clinical risk factors, in identifying patients at risk of death after major intra-abdominal, non-vascular surgery.
  
  
  METHODS
  Patients aged >55 yr, undergoing elective colorectal resection, radical nephrectomy, or cystectomy between June 2004 and May 2009 had CPET during their routine pre-assessment clinic visit. We performed a retrospective analysis of known clinical risk factors and data from CPET to assess their relationship to all-cause mortality after surgery.
  
  
  RESULTS
  Eight hundred and forty-seven patients underwent surgery, of whom 18 (2.1%) died. A clinical history of ischaemic heart disease (RR 3.1, 95% CI 1.3-7.7), a VE/VCO(2) >34 (RR 4.6, 95% CI 1.4-14.8), and an AT < or =10.9 ml kg(-1) min(-1) (RR 6.8, 95% CI 1.6-29.5) were all significant predictors of all-cause hospital and 90 day mortality. The effect of reduced AT was most pronounced in patients with no history of cardiac risk factors (RR 10.0, 95% CI 1.7-61.0).
  
  
  CONCLUSIONS
  The routine measurement of AT and VE/VCO(2) using CPET for patients undergoing high-risk surgery can accurately identify the majority of high-risk patients, while the use of clinical risk factors alone will only identify a relatively small proportion of at-risk patients.
authors.affiliation: Department of Anaesthetics, York Hospital, Wigginton Road, York YO31 8HE, UK. rjtw@mac.com
authors.forename: R J T
authors.initials: RJ
authors.lastname: Wilson
authors.forename: S
authors.initials: S
authors.lastname: Davies
authors.forename: D
authors.initials: D
authors.lastname: Yates
authors.forename: J
authors.initials: J
authors.lastname: Redman
authors.forename: M
authors.initials: M
authors.lastname: Stone
mesh_terms: D000005:Abdomen / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002423:Cause of Death; D003106:Colon / Q000601:surgery; D015653:Cystectomy / Q000009:adverse effects / Q000401:mortality; D004812:Epidemiologic Methods; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications / Q000401:mortality; D009392:Nephrectomy / Q000009:adverse effects / Q000401:mortality; D010101:Oxygen Consumption / Q000502:physiology*; D011183:Postoperative Complications; D011379:Prognosis; D011659:Pulmonary Gas Exchange / Q000502:physiology*; D012007:Rectum / Q000601:surgery