The impact of integrating nephrologists into the postoperative cardiac intensive care unit: a cohort study.

Background/aims: We evaluated the potential preventive effect of Nephrology On-Site (i.e. nephrologists integrated into the postoperative cardiac intensive care unit, ICU, team) versus Nephrology On-Demand (i.e. nephrology consultation depending on intensivist criteria) in the ICU on in-hospital outcomes.

Methods: This was a retrospective cohort study comparing outcomes during 2 consecutive time periods: from March 1, 2009 to February 28, 2010 with Nephrology On-Demand, and from March 1, 2010 to February 28, 2011 with Nephrology On-Site. Adult patients admitted to the postoperative cardiac ICU in an academic hospital in Mexico City were eligible. Patients with chronic kidney disease stage 5 or minimally invasive procedures were excluded.

Results: We analyzed 1,096 patients, 558 and 538 in the respective periods. The patients were 52.4 ± 16.2 years old, 56.1% were males, 17.2% had diabetes and 37.6% had hypertension. Further, the patients' median Euroscore was 5 (3-5) and their median Thakar score was 3 (2-4). With Nephrology On-Site, we observed a lower incidence of acute kidney injury [AKI; 25.7 vs. 31.9%, p = 0.02; adjusted OR 0.71 (0.53-0.95), p = 0.02], lower in-hospital mortality among patients with severe AKI [34.1 vs. 55.9%, p = 0.06; adjusted OR 0.33 (0.12-0.95), p = 0.04] and higher renal recovery [61.0 vs. 35.3%, p = 0.03; adjusted OR 3.57 (1.27-10.11), p = 0.02]. No differences were found in the length of stay at the ICU and mechanical ventilation.

Conclusion: Integrating nephrologists into the postoperative cardiac ICU team was associated with a lower incidence of AKI. Patients who developed severe AKI had lower in-hospital mortality and higher renal recovery.