ACUTE KIDNEY INJURY: A DESCRIPTIVE AND ANALYTICAL STUDY IN A PUBLIC HOSPITAL IN BUENOS AIRES, ARGENTINA.

Acute kidney injury (AKI) is becoming increasingly prevalent both in developing and developed countries, and it is associated with severe morbidity and mortality. AKI is common in the critically ill population, occurring in 35-50% of patients admitted to the intensive care unit (ICU).

Individuals who develop an AKI in the ICU have hospital mortality of more than 30%, the magnitude of which increases with the severity of AKI.AKI may increase the risk of chronic kidney disease (CKD) and end-stage renal disease. To date, there is little data in this regard in our country.

The clinical records of Ps developing AKI between August 1, 2022 and October 30, 2023 were reviewed.

154 Ps required dialysis in our institution, 37 of whom were already receiving dialysis due to their CKD and were therefore excluded from this analysis.

Some Ps received more than one type of therapy. We used the Fresenius MultiFiltrate PRO system for continuous dialysis, and Nipro for intermittent dialysis.

Their kidney function was assessed by estimating the glomerular filtration rate (eGFR), using CKD‑EPI and plasma creatinine. AKI was classified as per KDIGO.

117 Ps developed AKI.

Sex distribution: 78 men (66.6%) and 39 women (33.3%); average age: 58.17 years (19‑90); overall mortality rate: 50.42% (59 Ps).

50 Ps had comorbidities and 12 Ps were kidney transplant recipients.

The causes of AKI: sepsis: 63.2% (n: 74); cardio-renal: 20.5% (n: 20); obstructive: 8.5% (n: 10); nephrotoxic: 5.9% (n: 7); and rhabdomyolysis: 1.7% (n:2).

Regarding the type of renal replacement therapy, 114 of 117 Ps received renal replacement therapy. Of them, 90% received intermittent hemodialysis; 30%, continuous venovenous hemodiafiltration; and 30%, SLEDD.

In slow continuous therapies, the average dialysis time was 33.3 hrs (4-72).

Average number of hemodialysis sessions: 6.58 (1-21).

The overall mortality rate in our study was 50.4% (n: 59). Recovery from AKI was 32% (n: 38)

When comparing the groups of deceased and survivors, age was 64 vs. 52.8 (p<0.05) and there were no gender differences (39 M vs. 20 F).

In terms of comorbidities, the deceased Ps had more history of heart disease (25 vs. 14, p<0.05), and there were no differences in terms of HBP, DM, obesity and CKD not going on dialysis.

As regards the cause of AKI, sepsis was observed in 39 of the deceased Ps vs. 26 of the surviving Ps (p<0.05), and there were no differences in terms of other causes of AKI.

ICU admission and mechanical ventilation requirements in deceased and surviving groups: 55 vs. 39 (p<0.05) and 55 vs. 28 (p<0.05), respectively.

Of the 58 survivors, 34 (58.6%) recovered their renal function and 24 (41.4%) remained on dialysis. Comparing the Ps remaining on dialysis and those recovering, there was a history of CKD in 19/24 (79%) in the former, and in 10/34 (29.4%) (p<0.05) in the latter.

The overall mortality rates in AKI patients were similar to those described in the literature. Risk factors of mortality included old age, history of heart disease and ICU admission and mechanical ventilation requirements. The main cause of AKI was sepsis. The lack of renal function recovery was associated with a history of CKD.