Samuel Quan1, Neesh Pannu2, Todd Wilson1, Chad Ball3, Zhi Tan1, Marcello Tonelli1,4, Brenda R Hemmelgarn1,4, Elijah Dixon3,4, Matthew T James1,4. 1. Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. 2. Department of Medicine, University of Alberta, Edmonton, AB, Canada. 3. Department of Surgery, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. 4. Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
Abstract
BACKGROUND: Current guidelines recommend staging acute kidney injury (AKI) according to the serum creatinine (SCr) or urine output (UO) criteria that achieve the highest stage. There is little information about the implications of adding UO to SCr measurements for staging AKI outside intensive care units and after cardiac surgery. METHODS: We performed a cohort study of all adults without end-stage renal disease who underwent major noncardiac surgery between January 2005 and March 2011 in Calgary, AB, Canada. Participants required at least two SCr and UO measurements to be included. We examined the implications of adding UO to SCr to stage AKI based on Kidney Disease: Improving Global Outcomes criteria. Logistic and linear regression models were used to examine the associations between AKI stage and 30-day mortality or hospital length of stay (LOS), respectively. RESULTS: A total of 4229 (17%) surgical patients had sufficient SCr and UO measurements for inclusion in the cohort. The apparent incidence of postoperative AKI substantially increased with the addition of UO to SCr criteria (8.1% with SCr alone versus 64.0% with SCr and UO). Mortality for a given stage of AKI was lower when UO was added to SCr criteria (0.3, 3.2, 1.9 and 3.0% for no AKI and Stages 1, 2 and 3, respectively) versus with SCr alone (1.2, 4.2, 15.4 and 12.8%). However, among participants without AKI based on the SCr criterion, the odds of mortality and mean LOS both significantly increased with lower UO. Models that reclassified AKI stage based on UO in addition SCr criteria had the best discrimination for mortality and LOS. CONCLUSIONS: Adding UO to SCr criteria substantially increases the apparent incidence of AKI on hospital wards and significantly changes the prognostic implications of AKI identification and staging. These measures should not be considered equivalent criteria in AKI staging.
BACKGROUND: Current guidelines recommend staging acute kidney injury (AKI) according to the serum creatinine (SCr) or urine output (UO) criteria that achieve the highest stage. There is little information about the implications of adding UO to SCr measurements for staging AKI outside intensive care units and after cardiac surgery. METHODS: We performed a cohort study of all adults without end-stage renal disease who underwent major noncardiac surgery between January 2005 and March 2011 in Calgary, AB, Canada. Participants required at least two SCr and UO measurements to be included. We examined the implications of adding UO to SCr to stage AKI based on Kidney Disease: Improving Global Outcomes criteria. Logistic and linear regression models were used to examine the associations between AKI stage and 30-day mortality or hospital length of stay (LOS), respectively. RESULTS: A total of 4229 (17%) surgical patients had sufficient SCr and UO measurements for inclusion in the cohort. The apparent incidence of postoperative AKI substantially increased with the addition of UO to SCr criteria (8.1% with SCr alone versus 64.0% with SCr and UO). Mortality for a given stage of AKI was lower when UO was added to SCr criteria (0.3, 3.2, 1.9 and 3.0% for no AKI and Stages 1, 2 and 3, respectively) versus with SCr alone (1.2, 4.2, 15.4 and 12.8%). However, among participants without AKI based on the SCr criterion, the odds of mortality and mean LOS both significantly increased with lower UO. Models that reclassified AKI stage based on UO in addition SCr criteria had the best discrimination for mortality and LOS. CONCLUSIONS: Adding UO to SCr criteria substantially increases the apparent incidence of AKI on hospital wards and significantly changes the prognostic implications of AKI identification and staging. These measures should not be considered equivalent criteria in AKI staging.
Authors: Mitra K Nadim; Lui G Forni; Azra Bihorac; Charles Hobson; Jay L Koyner; Andrew Shaw; George J Arnaoutakis; Xiaoqiang Ding; Daniel T Engelman; Hrvoje Gasparovic; Vladimir Gasparovic; Charles A Herzog; Kianoush Kashani; Nevin Katz; Kathleen D Liu; Ravindra L Mehta; Marlies Ostermann; Neesh Pannu; Peter Pickkers; Susanna Price; Zaccaria Ricci; Jeffrey B Rich; Lokeswara R Sajja; Fred A Weaver; Alexander Zarbock; Claudio Ronco; John A Kellum Journal: J Am Heart Assoc Date: 2018-06-01 Impact factor: 5.501
Authors: Anthony Bonavia; Milad Javaherian; Alexander J Skojec; Vernon M Chinchilli; Berend Mets; Kunal Karamchandani Journal: Medicine (Baltimore) Date: 2019-08 Impact factor: 1.817