title: Perioperative hemoglobin area under the curve is an independent predictor of renal failure after cardiac surgery. Results from a Spanish multicenter retrospective cohort study.
abstract: Perioperative anemia is an important risk factor for cardiac surgery-associated acute kidney injury (CSA-AKI). Nonetheless, the severity of the anemia and the time in the perioperative period in which the hemoglobin level should be considered as a risk factor is conflicting. The present study introduces the concept of perioperative hemoglobin area under the curve (pHb-AUC) as a surrogate marker of the evolution of perioperative hemoglobin concentration. Through a retrospective analysis of prospectively collected data, we assessed this new variable as a risk factor for the development of acute kidney injury after cardiac surgery in 966 adult patients who underwent cardiac surgery with cardiopulmonary bypass, at twenty-three academic hospitals in Spain. Exclusion criteria were patients on renal replacement therapy, who needed a reoperation because of bleeding and/or with missing perioperative hemoglobin or creatinine values. Using a multivariate regression analysis, we found that a pHb-AUC <19 g/dL was an independent risk factor for CSA-AKI even after adjustment for intraoperative red blood cell transfusion (OR 1.41, p <0.05). It was also associated with mortality (OR 2.48, p <0.01) and prolonged hospital length of stay (4.67 ± 0.99 days, p <0.001).
authors.affiliation: Department of Anesthesia and Critical Care, Clínica Universidad de Navarra, Pamplona, Navarra, Spain.
authors.forename: Paula
authors.initials: P
authors.lastname: Duque-Sosa
authors.affiliation: Department of Internal Medicine, Division of Intermediate Care and Hospitalists Unit, Clínica Universidad de Navarra, Pamplona, Navarra Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Martínez-Urbistondo
authors.affiliation: Department of Anesthesia and Critical Care, Clínica Universidad de Navarra, Pamplona, Navarra, Spain.
authors.forename: Gemma
authors.initials: G
authors.lastname: Echarri
authors.affiliation: Department of Anesthesia and Critical Care, Clínica Universidad de Navarra, Pamplona, Navarra, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Callejas
authors.affiliation: Department of Anesthesia and Critical Care, Clínica Universidad de Navarra, Pamplona, Navarra, Spain.
authors.forename: María Josefa
authors.initials: MJ
authors.lastname: Iribarren
authors.affiliation: Department of Cardiovascular Surgery, Clínica Universidad de Navarra, Pamplona, Navarra, Spain.
authors.forename: Gregorio
authors.initials: G
authors.lastname: Rábago
authors.affiliation: Department of Anesthesia and Critical Care, Clínica Universidad de Navarra, Pamplona, Navarra, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Monedero
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D000368:Aged; D019540:Area Under Curve; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D005260:Female; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D059035:Perioperative Period; D011183:Postoperative Complications / Q000097:blood / Q000175:diagnosis / Q000209:etiology; D011237:Predictive Value of Tests; D011379:Prognosis; D000091402:Prohibitins; D051437:Renal Insufficiency / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D012189:Retrospective Studies; D012307:Risk Factors; D013030:Spain
chemical_list: D006454:Hemoglobins; C000717328:PHB protein, human; D000091402:Prohibitins