title: Ischemic Colitis after Cardiac Surgery: Can We Foresee the Threat?
abstract: BACKGROUND
  Ischemic colitis (IC) remains a great threat after cardiac surgery with use of extracorporeal circulation. We aimed to identify predictive risk factors and influence of early catecholamine therapy for this disease.
  
  
  METHODS
  We prospectively collected and analyzed data of 224 patients, who underwent laparotomy due to IC after initial cardiac surgery with use of extracorporeal circulation during 2002 and 2014. For further comparability 58 patients were identified, who underwent bypass surgery, aortic valve replacement or combination of both. Age ±5 years, sex, BMI ± 5, left ventricular function, peripheral arterial disease, diabetes and urgency status were used for match-pair analysis (1:1) to compare outcome and detect predictive risk factors. Highest catecholamine doses during 1 POD were compared for possible predictive potential.
  
  
  RESULTS
  Patients' baseline characteristics showed no significant differences. In-hospital mortality of the IC group with a mean age of 71 years (14% female) was significantly higher than the control group with a mean age of 70 (14% female) (67% vs. 16%, p<0.001). Despite significantly longer bypass time in the IC group (133 ± 68 vs. 101 ± 42, p = 0.003), cross-clamp time remained comparable (64 ± 33 vs. 56 ± 25 p = 0.150). The majority of the IC group suffered low-output syndrome (71% vs. 14%, p<0.001) leading to significant higher lactate values within first 24h after operation (55 ± 46 mg/dl vs. 31 ± 30 mg/dl, p = 0.002). Logistic regression revealed elevated lactate values to be significant predictor for colectomy during the postoperative course (HR 1.008, CI 95% 1.003-1.014, p = 0.003). However, Receiver Operating Characteristic Curve calculates a cut-off value for lactate of 22.5 mg/dl (sensitivity 73% and specificity 57%). Furthermore, multivariate analysis showed low-output syndrome (HR 4.301, CI 95% 2.108-8.776, p<0.001) and vasopressin therapy (HR 1.108, CI 95% 1.012-1.213, p = 0.027) significantly influencing necessity of laparotomy.
  
  
  CONCLUSIONS
  Patients who undergo laparotomy for IC after initial cardiac surgery have a substantial in-hospital mortality risk. Early postoperative catecholamine levels do not influence the development of an IC except vasopressin. Elevated lactate remains merely a vague predictive risk factor.
authors.affiliation: Department of Cardiac Surgery, Heart and Marfan Center-University of Heidelberg, Heidelberg, Germany.
authors.forename: Rawa
authors.initials: R
authors.lastname: Arif
authors.affiliation: Department of Cardiac Surgery, Heart and Marfan Center-University of Heidelberg, Heidelberg, Germany.
authors.forename: Mina
authors.initials: M
authors.lastname: Farag
authors.affiliation: Department of Cardiac Surgery, Heart and Marfan Center-University of Heidelberg, Heidelberg, Germany.
authors.forename: Marcin
authors.initials: M
authors.lastname: Zaradzki
authors.affiliation: Department of Visceral, Thoracic and Vascular Surgery, University Hospital Carl Gustav Carus, Technical University Dresden, Fetscherstr. Dresden, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Reissfelder
authors.affiliation: Department of General, Visceral and Transplantation Surgery, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Pianka
authors.affiliation: Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bruckner
authors.affiliation: Department of Cardiac Surgery, Heart and Marfan Center-University of Heidelberg, Heidelberg, Germany.
authors.forename: Jamila
authors.initials: J
authors.lastname: Kremer
authors.affiliation: Department of Cardiac Surgery, Heart and Marfan Center-University of Heidelberg, Heidelberg, Germany.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Franz
authors.affiliation: Department of Cardiac Surgery, Heart and Marfan Center-University of Heidelberg, Heidelberg, Germany.
authors.forename: Arjang
authors.initials: A
authors.lastname: Ruhparwar
authors.affiliation: Department of Cardiac Surgery, Heart and Marfan Center-University of Heidelberg, Heidelberg, Germany.
authors.forename: Gabor
authors.initials: G
authors.lastname: Szabo
authors.affiliation: Department of Cardiac Surgery, Heart and Marfan Center-University of Heidelberg, Heidelberg, Germany.
authors.forename: Carsten J
authors.initials: CJ
authors.lastname: Beller
authors.affiliation: Department of Cardiac Surgery, Heart and Marfan Center-University of Heidelberg, Heidelberg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Karck
authors.affiliation: Department of Cardiac Surgery, HaerzZenter-INCCI, rue Ernest-Barblé, Luxembourg, Luxembourg.
authors.forename: Klaus
authors.initials: K
authors.lastname: Kallenbach
authors.affiliation: Department of Cardiac Surgery, Heart and Marfan Center-University of Heidelberg, Heidelberg, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Weymann
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000601:surgery; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D002395:Catecholamines / Q000627:therapeutic use; D017091:Colitis, Ischemic / Q000097:blood / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality; D001026:Coronary Artery Bypass / Q000009:adverse effects; D005112:Extracorporeal Circulation / Q000009:adverse effects; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D012372:ROC Curve; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D002395:Catecholamines; D019344:Lactic Acid