Renal Support
Description General measures Description Acute kidney injury (AKI) in critical care is a complex, heterogenous clinical syndrome presenting with varying severities, trajectories, and outcomes. LoE: IVb xii See Acute Kidney Injury , for further details. Table 23.1: Staging/Severity of Acute Kidney Injury Stage Serum creatinine Urine output 1 1.5-1.9 times baseline OR ≥26.5 µmol/l (≥ 0.3 mg/dl) inc
Description
Acute kidney injury (AKI) in critical care is a complex, heterogenous clinical syndrome presenting with varying severities, trajectories, and outcomes.
See Acute Kidney Injury, for further details.
Table 23.1: Staging/Severity of Acute Kidney Injury
| Stage | Serum creatinine | Urine output |
| 1 | 1.5-1.9 times baseline OR ≥26.5 µmol/l (≥ 0.3 mg/dl) increase |
<0.5ml/kg/h for 6-12 hours |
| 2 | 2.0-2.9 times baseline | <0.5ml/kg/h for ≥ 12 hours |
| 3 | 3 times baseline OR Increase in serum creatinine to ≥353.6 µmol/l (≥ 4.0 mg/dl) OR Initiation of kidney replacement therapy OR In patients <18 years, decrease in eGFR to <35 ml/min per 1.73 m2 |
<0.3ml/kg/h for ≥ 24 hours OR Anuria for ≥ 12 hours |
Taken from: Kidney Disease: Improving Global Outcomes (KDIGO). Acute Kidney Injury (AKI). 2012 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline for Acute Kidney Injury (AKI). 2012. Available at: https://kdigo.org/guidelines/acute-kidney-injury/
General Measures
In all patients at risk for, and with AKI:
- Avoid nephrotoxic agents (e.g. aminoglycosides; amphotericin B, NSAIDs).
- Where medication cannot be avoided, dose appropriately with use of therapeutic drug monitoring where available.
- Dose-adjust medications for reduced GFR.
- Ensure volume status is appropriate.
- Ensure optimal perfusion pressure.
- Consider functional haemodynamic monitoring.
- Monitor urine output (UO) and serum creatinine.
- Avoid hyperglycaemia.
- Consider alternatives to radiocontrast material.
- Search for reversible causes and treat.
- Consider invasive diagnostic workup.
Fluid therapy
- Use balanced salt solutions.
- For patients at high risk of AKI that also require imaging with iodine-based contrast media (e.g. eGFR <30ml/min/1.73m2 , renal transplant, large volume of contrast medium to be used, intra-arterial administration of contrast medium), ensure adequate intravenous volume expansion with 0.9% sodium chloride solution if not already volume replete.
Nutrition in acute kidney injury
- Provide total energy intake of 20-30 kCal/kg/d in all AKI stages.
- Feeds may be given orally, enterally, or parenterally depending on gut functionality and integrity.
- Do not restrict protein intake with the goal of preventing or delaying Kidney Replacement Therapy (KRT).
- Consult a dietitian as necessary and refer to the National Department of Health Clinical Nutrition Guidelines.
CAUTION
The following drugs are NOT RECOMMENDED for the prevention of AKI:
- Diuretics
- Low dose dopamine
- N-acetyl cysteine in critically ill patients with hypotension or for prevention in post-surgical AKI.
The following class of drug is NOT RECOMMENDED for the treatment of AKI:
- Diuretics (except in the management of fluid overload).
Standard Treatment Guidelines and Essential Medicines List for South Africa Adult Hospital _Chapter 23: Adult Critical Care_NEMLC Medicine Recommendations Review Cycle_ 2020_2023