title: Inferior mesenteric venous sampling, pulse oximetry, and assessment of colonic perfusion during aortic aneurysm surgery.
abstract: Ischemic colitis is a serious complication of aortic surgery. The condition continues to be difficult to diagnose at an early stage. This study monitors the biochemical changes in systemic and selective inferior mesenteric vein (IMV) blood sampling during aortic surgery and compares the reproducibility of this method to intraoperative colonic pulse oximetry in a series of 18 patients undergoing infrarenal aortic aneurysm repair. Base excess, pH, pCO2, and lactate were altered by aortic cross-clamping but returned to normal within 48 hr. IMV inorganic phosphate levels were higher than systemic values, suggesting improved sensitivity with selective sampling. BB isoenzymes of creatine kinase remained normal in all patients. Pulse oximetry signals were inconsistently obtained from the colon. This study establishes the physiological changes in IMV biochemistry during aortic surgery. Unlike intraoperative pulse oximetry, selective IMV sampling provides reproducible measurements of colonic perfusion. This simple and safe technique warrants further assessment of its accuracy at diagnosing ischemic colitis.
authors.affiliation: Department of Surgery, St. Vincent's Hospital, Elm Park, Dublin, Ireland.
authors.forename: C P
authors.initials: CP
authors.lastname: Delaney
authors.forename: N F
authors.initials: NF
authors.lastname: Couse
authors.forename: D
authors.initials: D
authors.lastname: Mehigan
authors.forename: T V
authors.initials: TV
authors.lastname: Keaveny
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000469:Alkaline Phosphatase / Q000097:blood; D001014:Aortic Aneurysm / Q000378:metabolism / Q000503:physiopathology / Q000601:surgery*; D001663:Bilirubin / Q000097:blood; D001800:Blood Specimen Collection; D002245:Carbon Dioxide / Q000378:metabolism; D003106:Colon / Q000098:blood supply* / Q000378:metabolism; D003113:Colonoscopy; D003402:Creatine Kinase / Q000097:blood; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007432:Intraoperative Period; D007527:Isoenzymes; D019344:Lactic Acid / Q000097:blood; D008642:Mesenteric Veins; D010092:Oximetry; D010313:Partial Pressure; D010710:Phosphates / Q000097:blood; D012039:Regional Blood Flow; D015203:Reproducibility of Results; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D007527:Isoenzymes; D010710:Phosphates; D002245:Carbon Dioxide; D019344:Lactic Acid; D005723:gamma-Glutamyltransferase; D000410:Alanine Transaminase; D003402:Creatine Kinase; D000469:Alkaline Phosphatase; D001663:Bilirubin