Hyperchloremia and postoperative acute kidney injury: a retrospective analysis of data from the surgical intensive care unit

Abstract

BackgroundWhether perioperative hyperchloremia can induce postoperative acute kidney injury (AKI) is controversial. We investigated the association between perioperative hyperchloremia and postoperative AKI in patients admitted to the intensive care unit (ICU) after surgery.MethodsWe performed a retrospective observational study of patients admitted to the surgical ICU at a single tertiary care hospital between January 2011 and June 2016. Our primary objective was to determine whether hyperchloremia or an increase in serum chloride levels was associated with postoperative AKI. Perioperative hyperchloremia was defined as serum chloride levels ≥ 110 mmol·L− 1 during postoperative days (PODs) 0–3. The increase in serum chloride levels was defined as the difference between preoperative and maximum postoperative serum chloride levels during the first 3 days after surgery.ResultsOf the 7991 patients included in the final analysis, 1876 (23.5%) developed hyperchloremia during PODs 0–3, and 1187 (14.9%) developed postoperative AKI. Exposure to hyperchloremia during the first 3 days after surgery was not associated with postoperative AKI (odds ratio, 1.09; 95% confidence interval, 0.80–1.49; P = 0.571). However, among patients with preoperative chronic kidney disease stage ≥ 3 (estimated glomerular filtration rate < 60 mL·min− 1·1.73·m− 2), the incidence of postoperative AKI was higher in patients with an increase > 6 mmol·L− 1 in serum chloride levels than in patients with an increase ≤ 1 mmol·L− 1 (odds ratio, 1.42; 95% confidence interval, 1.09–1.84; P = 0.009). In addition, the incidence of postoperative AKI stage ≥ 2 was not associated with exposure to hyperchloremia or with the increase in serum chloride levels during PODs 0–3, regardless of preoperative kidney function.ConclusionsExposure to perioperative hyperchloremia is not associated with postoperative AKI in surgical ICU patients. However, in patients with moderate-to-severe chronic kidney disease (stage ≥ 3), a substantial perioperative increase in serum chloride levels may reflect a higher risk of AKI.Electronic supplementary materialThe online version of this article (10.1186/s13054-018-2216-5) contains supplementary material, which is available to authorized users.

Fluctuations in Serum Chloride and Acute Kidney Injury among Critically Ill Patients: A Retrospective Association Study

“…This study succeeds a previous study [18] that analyzed the medical records of patients in the surgical ICU at our institution from 2011 to 2016. The previous study reported that exposure to hyperchloremia in the postoperative period in the surgical ICU was not associated with the incidence of AKI.…”

“…The difference in the results regarding positive fluctuations in Cl − between this study and our previous study is also interesting [18]. In our previous study, we found that hyperchloremia (>110 mmol L −1 ) was not associated with postoperative AKI in the surgical ICU, and there was a positive association in the increase from the preoperative Cl − (which was measured within 1 month prior to surgery) to the maximum Cl − measured 0–3 days postoperatively in patients with a CKD stage ≥3.…”

Exposure to Hyperchloremia Is Associated with Poor Early Recovery of Kidney Graft Function after Living-Donor Kidney Transplantation: A Propensity Score-Matching Analysis

“…Many studies have examined the impact of hyperchloremia on AKI in critically ill patients, but debate persists regarding the relation between hyperchloremia and the occurrence of AKI [5,6,23,30,31]. A study of severely septic patients in the ICU showed that hyperchloremia was common in these patients due to aggressive fluid resuscitation, but that neither hyperchloremia nor an increase in the serum chloride level was associated with an increased risk of AKI development within the first three days of ICU admission [23].…”

Hyperchloremia-associated acute chronic kidney injury: beware of confounders!

“…We read with great interest the recent paper by Oh et al [1] investigating the association between perioperative hyperchloremia and postoperative acute kidney injury (AKI) in a large population of postsurgical patients admitted to the intensive care unit (ICU). One of the conclusions was that a substantial perioperative increase in serum chloride levels may reflect a higher risk of AKI in patients with moderate-to-severe chronic kidney disease (CKD) [1].…”

“…One of the conclusions was that a substantial perioperative increase in serum chloride levels may reflect a higher risk of AKI in patients with moderate-to-severe chronic kidney disease (CKD) [1]. …”