ROLE OF FUROSEMIDE STRESS TEST TO PREDICT OUTCOMES IN PATIENTS WITH ACUTE KIDNEY INJURY

Introduction:

Currently, serum creatinine and urine output are using to diagnose and manage of AKI but they have some limitations because even after controlling for numerous potential confounders, those with AKI still have higher morbidities and mortality. In patients with AKI, the furosemide stress test (FST) is an assessment tool for renal tubular function in clinically euvolemic patients and it has the predictive capacity to identify those with severe and progressive AKI.

Methods:

This study was a prospective, hospital based cross sectional analytical study conducted between October 2021 and September 2022 in No (2) Defence Services General Hospital (1000 bedded) Naypyitaw, Myanmar. Patients who were found to have AKI during hospital admission and systolic blood pressure ≥ 90 mmHg were given furosemide (1mg/kg) in furosemide naive patients and (1.5mg/kg) in history of previous furosemide exposure within 7 days. Patient who had at least 200 ml urine output after 2 hr of furosemide injection were defined as passed furosemide stress test and less than 200 ml was defined as failed furosemide stress test. AKI outcomes like worsening of AKI, dialysis requirement and hospital mortality were recorded and analysis was done whether furosemide stress test results could be predicted these outcomes in patients with AKI. Worsening of AKI was defined in patient whose condition was worsen to AKI -KDIGO stage 3 from early stages 1 or 2 during study period and dialysis requirement was defined patients who required haemodialysis during hospitalization and hospital mortality was defined patient was expired during hospitalization. Outcomes were followed at the time of furosemide injection to when the patients who was discharged from hospital or expired during hospitalization. 

Results:

After total of 178 patients with AKI were analysed, 46 (25.8%) patients suffered at least one of three outcomes and the rest 132 (74.2%) of patients were stable or recovered. Sixteen of 108 (16.7%) were worsening to stage 3 AKI from early stages, 31 of 178 (17.4%) patients were required dialysis and 26 of 178 (14.6%) were death during hospital period. The mean age was 49.1±15.2 years with the oldest and youngest age were 84 and 19 years respectively. About 70% of population were male because study area was done in military hospital. After furosemide stress test, the first 2 hours urine output < 200 ml had good predictive capacity for worsening of AKI with an AUC (±SEM) of 0.94 ± 0.037 (p<0.001), dialysis requirement with an AUC (±SEM) of 0.96 ± 0.013 (p<0.001), all cause hospital mortality with an AUC (±SEM) of 0.82 ± 0.05 (p<0.001). Majority of the patients were safe because almost 90 % of patients had no side effects. A few side effects about 10 % were found such as hypotension (0.6%), hyponatremia (1.1%), hypokalaemia (9%) respectively after furosemide injection. No patient was experienced tinnitus after furosemide injection.

Conclusions:

Furosemide stress test found to have ability to predict outcomes in patients with AKI and it can be used to make the decision for early referral for nephrologist consultation for further management especially in low resources areas.  

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.