Difference between pre-operative and cardiopulmonary bypass mean arterial pressure is independently associated with early cardiac surgery-associated acute kidney injury
Cardiac surgery-associated acute kidney injury (CSA-AKI) contributes to increased morbidity and mortality. However, its pathophysiology remains incompletely understood.
We hypothesized that intra-operative mean arterial pressure (MAP) relative to pre-operative MAP would be an important predisposing factor for CSA-AKI.
Methods: We performed a prospective observational study of 157 consecutive high-risk patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). The primary exposure was delta MAP, defined as the pre-operative MAP minus average MAP during CPB.
Secondary exposure was CPB flow. The primary outcome was early CSA-AKI, defined by a minimum RIFLE class - RISK.
Univariate and multivariate logistic regression were performed to explore for association between delta MAP and CSA-AKI.
Results: Mean (SD) age was 65.9+/-14.7 years, 70.1% were male, 47.8% had isolated coronary bypass graft (CABG) surgery, 24.2% had isolated valve surgery and 16.6% had combined procedures. Mean (SD) pre-operative, intra-operative and delta MAP were 86.6 (13.2), 57.4 (5.0) and 29.4 (13.5) mmHg, respectively.
Sixty-five patients (41%) developed CSA-AKI within in the first 24 hours post surgery. By multivariate logistic regression, a delta MAP[greater than or equal to]26 mmHg (odds ratio [OR], 2.8; 95%CI, 1.3-6.1, p=0.009) and CPB flow rate [greater than or equal to]54 mL/kg/min (OR, 0.2, 0.1-0.5, p<0.001) were independently associated with CSA-AKI.
Additional variables associated with CSA-AKI included use of a side-biting aortic clamp (OR, 3.0; 1.3-7.1, p=0.012), and body mass index [greater than or equal to]25 (OR, 4.2; 1.6-11.2, p=0.004).
Conclusion: A large delta MAP and lower CPB flow during cardiac surgery are independently associated with early post-operative CSA-AKI in high-risk patients. Delta MAP represents a potentially modifiable intra-operative factor for development of CSA-AKI that necessitates further inquiry.
Author: Hussein KanjiCostas SchulzeMarilou Hervas-MaloPeter WangDavid RossMohamad ZibdawiSean Bagshaw
Credits/Source: Journal of Cardiothoracic Surgery 2010, 5:71
Published on: 2010-09-08
Copyright by the authors listed above - made available via BioMedCentral (Open Access). Please
make sure to read our disclaimer prior to contacting 7thSpace Interactive. To contact our editors, visit our online helpdesk. If you wish submit your own press release, click here.
Social Bookmarking
RETWEET This! | Digg this! | Post to del.icio.us | Post to Furl | Add to Netscape | Add to Yahoo! | Rojo
|
|
