title: Miniaturized cardiopulmonary bypass and acute kidney injury in coronary artery bypass graft surgery.
abstract: BACKGROUND
  Acute kidney injury (AKI) is one of the most important complications after on-pump coronary artery bypass graft surgery (CABG). Miniaturized cardiopulmonary bypass (mini-CPB) systems have been developed to allow the ease of on-pump surgery but tempering the disadvantages. Whether mini-CPB reduces the incidence of AKI remains to be determined.
  
  
  METHODS
  Using a propensity score matched analysis, we investigated the occurrence of AKI among patients undergoing CABG on mini-CPB (n = 104) versus conventional CPB (n = 601). Acute kidney injury was defined according to the recent Acute Kidney Injury Network classification.
  
  
  RESULTS
  Overall, acute kidney injury developed in 274 of 705 patients (38.8%). A total of 27 of 705 patients (3.8%) required renal replacement therapy. The median postoperative length of intensive care unit stay in survivors with AKI was 5.4 (3.9 to 6.8) days compared with 2.0 (1.0 to 3.0) days for patients without AKI (p = 0.0002). The overall incidence of AKI for patients undergoing mini-CPB was 30 of 104 (28.8%) compared with 244 of 601 (40.5%) for patients undergoing conventional CPB (p = 0.03). In the propensity score matched-pair statistical analysis, mini-CPB was independently associated with a decreased incidence of AKI (adjusted odds ratio [OR] 0.61; 95% confidence interval [CI]: 0.38 to 0.97). Other variables independently associated with AKI were preoperative glomerular filtration rate (OR 0.988 for 1 mL.min(-1).1.73 m(-2) increase; 95% CI: 0.98 to 0.99), postoperative red blood cell transfusion (OR 1.58; 95% CI: 1.12 to 2.23); CPB time (OR 1.005 for 1-minute increase; 95% CI: 1.0 to 1.009), and postoperative low output syndrome (OR 1.72; 95% CI: 1.23 to 2.41).
  
  
  CONCLUSIONS
  The present study showed that mini-CPB is associated with a lower incidence of AKI when compared with conventional CPB among patients undergoing CABG.
authors.affiliation: Department of Cardiac Surgery, II School of Medicine, University of Rome La Sapienza, Policlinico S. Andrea, Rome, Italy. u2benedetto@libero.it
authors.forename: Umberto
authors.initials: U
authors.lastname: Benedetto
authors.forename: Remo
authors.initials: R
authors.lastname: Luciani
authors.forename: Massimo
authors.initials: M
authors.lastname: Goracci
authors.forename: Fabio
authors.initials: F
authors.lastname: Capuano
authors.forename: Simone
authors.initials: S
authors.lastname: Refice
authors.forename: Emiliano
authors.initials: E
authors.lastname: Angeloni
authors.forename: Antonino
authors.initials: A
authors.lastname: Roscitano
authors.forename: Riccardo
authors.initials: R
authors.lastname: Sinatra
mesh_terms: D058186:Acute Kidney Injury / Q000209:etiology*; D000368:Aged; D002315:Cardiopulmonary Bypass / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods*; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000379:methods; D003404:Creatinine / Q000097:blood; D004867:Equipment Design; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D015994:Incidence; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000517:prevention & control; D017582:Renal Replacement Therapy; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D003404:Creatinine