Furosemide Stress Test (FST) for AKI Progression
Functional test predicting progression to severe AKI (Chawla 2013). Single-dose IV furosemide (adults: 1.0 mg/kg if loop-naïve, 1.5 mg/kg if prior loop exposure); measure 2-hour urine output. Output < 200 mL in 2 h indicates non-responsiveness and high risk of progression. Children: use a children's formulary.
Score interpretation
2-hour urine output ≥ 200 mL after the furosemide dose.
→ Continue standard AKI care: stop nephrotoxins, optimise volume status, monitor creatinine and urine output.
< 200 mL in 2 hours predicted progression to stage 3 AKI with sensitivity 87.1 % and specificity 84.1 % (Chawla 2013) and predicted renal replacement therapy (Koyner 2015).
→ Early nephrology / critical care review and plan for possible renal replacement therapy. Non-response alone is not an indication to start RRT: early RRT in non-responders did not change 28-day mortality (Lumlertgul 2018).
Interpretation bands for the Furosemide Stress Test. Apply clinical judgement and local guidance.
References
Related
Curated clinical cross-links plus same-class fallbacks.
- Furosemide (IV — ICU) · Loop Diuretic
- Hydrocortisone (ICU — Stress Dosing) · Corticosteroid (ICU/Septic Shock)
- Furosemide · Diuretic
- Dobutamine (Acute HF / Stress Echo) · Inotrope / Acute Heart Failure
- Amiloride hydrochloride · Potassium-sparing diuretic (epithelial Na+ channel blocker)
- Furosemide with triamterene · Loop diuretic + potassium-sparing
- Hyperkalaemia Management · UK Kidney Association Guidelines 2020; NICE CKD Guidelines
- Rhabdomyolysis · Renal Association 2018; UpToDate 2024
- Hypocalcaemia (Adult) · Society for Endocrinology
- SIADH (Endocrine Perspective) · European Hyponatraemia Guidelines 2014
- Hepatorenal Syndrome · EASL 2018; ICA 2015
- Acute Kidney Injury (AKI) · KDIGO 2012 / NICE AKI 2019
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.