Incidence of acute kidney injury in obese patients undergoing cardiac surgery.

Abstract

OBJECTIVE: To determine the incidence of acute renal injury in obese patients undergoing Cardiac Surgery in the Adult Intensive Care Unit (ICU) at the Clinical Hospital.

DESIGN: retrospective cohort.

PARTICIPANTS AND INCLUSION CRITERIA: Patients older than 18 years undergoing any cardiac surgery, admitted to the ICU in the period of time between 2016 and 2019. A total of 77 patients were recruited consecutively, matched 16/53 (exposed / not exposed).

No interventions were performed.

OUTCOMES: incidence of acute renal injury in obese patients, days of hospitalization, days of mechanical ventilation, frequency of tracheostomy, frequency of Acute Renal Injury and staging of Kidney Disease: Improving Global Outcomes (KDIGO), frequency of requirement of renal replacement therapy, mortality.

RESULTS: 66% male. The mean age of the sample was 54.12 ± 16.07. The baseline variables for the obese / non-obese cohorts were similar in both groups. Myocardial revascularization surgery was the most prevalent. The frequency of obese patients is 24 patients (31%). The frequency of acute kidney injury in the general population 62%. The incidence of acute kidney injury in the obese population was 79% with RR: 1.44, p <0.05. The outcomes: hospitalization days, ventilator days, hemodialysis, tracheostomy and mortality were more frequent in the obese group.

CONCLUSIONS: The incidence of acute kidney injury in the obese cohort was 79%, most of them KDIGO stage 3. All adverse secondary outcomes (except frequency of KDIGO stage 1) are more frequent in the obese population undergoing cardiac surgery.

Key words: obesity, cardiac surgical procedures, acute kidney injury, critical care.