Injúria renal aguda em pacientes de terapia intensiva: incidência e perfil clínico-epidemiológico

Abstract

Objective: To estimate the incidence of patients admitted to intensive care unit (ICU) beds affected by acute kidney injury (AKI). Methodology: Retrospective cohort study, carried out using data collected by consulting the medical records of patients admitted to the ICU at a hospital in the north of Rio Grande do Sul, from January to December 2022. All individuals were included, except those with stage 4 or 5 chronic kidney disease, AKI prior to hospitalization, a history of kidney transplantation, nephrectomy, single kidney, previous ICU admission and a stay of less than 24 hours. The diagnosis of AKI was defined by analyzing renal biomarkers and urine output criteria, according to the KDIGO guideline. The analyses included the absolute (n) and relative (%) distribution of the frequencies of the categorical variables and measures of central tendency and dispersion for the numerical variables. Results: The total study sample included 528 patients, 41.7% of whom had AKI. Regarding AKI, it was present in 54% of those admitted for respiratory causes, with its occurrence increasing in hospitalizations of more than 3 weeks (77.4%) and in those with higher degrees of obesity (58.1%). Regarding the time of admission, patients with clinical admissions (51.9%) and with diastolic arterial hypotension (52.9%) were predominantly in the AKI group. Among patients requiring mechanical ventilation, 44% were in the AKI group, as well as those with high ventilation standards (57.1%), being respiratory diseases the condition with the highest percentage of patients with ARI (64.9%). Among the drugs used, 48.3% of patients using intravenous contrast developed AKI, followed by specific antibiotics such as vancomycin and aminoglycosides, which accounted for 47.2%. In terms of symptoms, 66.6% of those with voiding alterations developed AKI and 59.4% of those with headaches. Laboratory results showed a mean creatinine level of 2.14 mg/dL (± 1.09) on the day of AKI, with 91.1% of patients having levels higher than 1.2 mg/dL. Dysnatremia was prevalent in around 85% of patients, and metabolic acidosis was also common, with a mean pH of 7.33 (± 0.14). Diuresis was predominantly non-oliguric (74.8%), and among the causes of AKI there was a predominance of pre-renal (50%). The time to onset of AKI was up to 24 hours in 67.9% of cases and only 14.6% of patients required renal replacement therapy (RRT). Among the outcomes, 86.5% of the patients who died were in the AKI group. Conclusion: Despite the limitations, the findings are consistent with recent studies, highlighting the complexity and severity of AKI in critically ill patients. In this study, parameters such as dysnatremia, metabolic acidosis and the occurrence of respiratory diseases were higher than expected. This study can contribute to similar studies, seeking to better understand the relationships, outcomes and dynamics of AKI.