Inpatient and outpatient nephrology management of critically ill patients with acute kidney injury.

Introduction: Acute kidney injury (AKI) during critical illness increases the risk of subsequent chronic kidney disease. Guidelines recommend inpatient nephrology assessment and review at 3 months.

Objectives: To quantify the prevalence and predictors of inpatient and outpatient nephrology follow-up of AKI patients admitted to critical care areas within a tertiary hospital.

Methods: Retrospective study of all critically ill adults with AKI between January 1, 2012 and December 31, 2016 with a baseline estimated glomerular filtration rate (eGFR) >30 mL/min/1.73 m and alive and independent of renal replacement therapy for 30 days after hospital discharge. We used logistic regression models to examine the primary outcome of nephrology review at 3 months. Secondary outcomes included inpatient nephrology review, renal recovery at discharge and the development of a major adverse kidney event (MAKE) at 1 year.

Results: Of 702 critically ill patients with AKI (mean age 66 years, 64% male, baseline eGFR 78 mL/min/1.73 m ), 43 patients (6%) received nephrology follow-up at 3 months and 63 patients (9%) at 1 year. Nephrology follow-up occurred more frequently in patients with a higher baseline creatinine, a higher discharge creatinine and greater severity of AKI. Seventy patients (10%) underwent inpatient nephrology review. Overall, 414 (59%) had recovery of renal function by the time of discharge and 239 (34%) developed a MAKE at 12 months.

Conclusion: Inpatient and outpatient nephrology follow-up of AKI patients after admission to a critical care area was uncommon although one-third developed a MAKE. These findings provide the rationale for controlled studies of nephrology follow-up.