Key Points
- Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets and reassess frequently.
- Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.
Algorithm
- Confirm AKI and stage with KDIGO; review meds and exposures; assess volume status.
- Differentiate prerenal vs intrinsic vs postrenal with UA/sediment, indices, and ultrasound.
- Treat cause; manage complications (K+, acidosis, volume); call nephrology for RRT indications (AEIOU).
Clinical Synopsis & Reasoning
AKI is an abrupt decline in kidney function. Identify prerenal, intrinsic, and postrenal causes using history, exam, labs, and ultrasound; stage using KDIGO criteria; stop nephrotoxins; optimize hemodynamics; and involve nephrology for refractory complications or RRT indications.
Treatment Strategy & Disposition
Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.
Epidemiology / Risk Factors
- Risk varies by comorbidity and precipitants; see citations for condition‑specific data.
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|---|---|---|
| Urinalysis with sediment and FeNa/FeUrea | Etiology | Prerenal vs ATN vs GN | Casts guide diagnosis |
| Renal ultrasound | Postrenal | Hydronephrosis | Quick screen |
| Daily weights, I/O, and medication review | Management | Volume and nephrotoxins | Titrate fluids/diuretics |
High-Risk & Disposition Triggers
| Trigger | Why it matters | Action |
|---|---|---|
| Refractory hyperkalemia/pulmonary edema/uremia | Dialysis indication | Urgent RRT |
| Rapid Cr rise or anuria | Progression | Nephrology consult |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|---|---|---|---|
| Balanced crystalloids for prerenal states | Fluids | Hours | Restore perfusion | Avoid overload |
| Diuretics for volume overload | Diuretic | Hours | Symptom control | Does not treat ATN per se |
| Immunosuppression for GN (selected) | Disease-modifying | Days-weeks | Condition-specific | Specialist guided |
Prognosis / Complications
- Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.
Patient Education / Counseling
- Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.
References
- KDIGO AKI guideline — Link
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