Hospital-acquired acute kidney injury in medical, surgical, and intensive care unit: A comparative study

Acute kidney injury (AKI) is a common complication in hospitalized patients. There are few comparative studies on hospital-acquired AKI (HAAKI) in medical, surgical, and ICU patients. This study was conducted to compare the epidemiological characteristics, clinical profiles, and outcomes of HAAKI among these three units. All adult patients (>18 years) of either gender who developed AKI based on RIFLE criteria (using serum creatinine), 48 h after hospitalization were included in the study. Patients of acute on chronic renal failure and AKI in pregnancy were excluded. Incidence of HAAKI in medical, surgical, and ICU wards were 0.54%, 0.72%, and 2.2% respectively (P < 0.0001). There was no difference in age distribution among the groups, but onset of HAAKI was earliest in the medical ward (P = 0.001). RIFLE-R was the most common AKI in medical (39.2%) and ICU (50%) wards but in the surgical ward, it was RIFLE-F that was most common (52.6%). Acute tubular necrosis was more common in ICU (P = 0.043). Most common etiology of HAAKI in medical unit was drug induced (39.2%), whereas in surgical and ICU, it was sepsis (34% and 35.2% respectively). Mortality in ICU, surgical and medical units were 73.5%, 43.42%, and 37.2%, respectively (P = 0.003). Length of hospital stay in surgical, ICU and medical units were different (P = 0.007). This study highlights that the characters of HAAKI are different in some aspects among different hospital settings.