What is the antihypertensive (blood pressure medication) of choice for Acute Kidney Injury (AKI)?

Antihypertensive of Choice for Acute Kidney Injury

For patients with acute kidney injury (AKI), ACE inhibitors or ARBs should be avoided, and calcium channel blockers (particularly dihydropyridine CCBs) are the preferred first-line antihypertensive agents, with careful monitoring of blood pressure to avoid hypotension. 1

Pathophysiology and Considerations in AKI

Hypertension is highly prevalent in AKI, with rates varying by etiology:

• 85% in post-renal AKI
• 75% in intrinsic renal AKI
• 30% in pre-renal AKI 2

Management of hypertension in AKI requires careful consideration of the following factors:

1. Avoid medications that worsen kidney function
2. Maintain adequate renal perfusion
3. Prevent further kidney damage

First-Line Antihypertensive Choices in AKI

Recommended:

• Dihydropyridine calcium channel blockers (e.g., amlodipine) 3, 1
  • Effectively lower blood pressure without reducing renal blood flow
  • Do not typically worsen kidney function
  • FDA-approved for hypertension with demonstrated cardiovascular benefits 4

Avoid or Use with Extreme Caution:

• ACE inhibitors and ARBs 3

  • Can cause AKI and hyperkalemia
  • May impair intrarenal blood flow
  • Should be discontinued during AKI episodes

• Diuretics 3

  • Not recommended to prevent or treat AKI except for volume overload management
  • Can worsen pre-renal AKI by reducing intravascular volume

Monitoring and Management Algorithm

1. Identify and address the underlying cause of AKI

   • Remove potential precipitating factors (nephrotoxic drugs, contrast media)
   • Optimize volume status 3

2. Blood pressure management:

   • For BP 140-159/90-99 mmHg: Start with single agent (dihydropyridine CCB)
   • For BP ≥160/100 mmHg: Consider two agents 3

3. Monitoring requirements:

   • Monitor serum creatinine and potassium regularly
   • Assess for signs of volume overload or depletion
   • Watch for hypotensive episodes, especially in dialysis patients 2

Special Considerations

• Dialysis patients: Higher risk of uncontrolled hypertension requiring more antihypertensive medications, but also at risk for intradialytic hypotension 2

• Intravenous antihypertensives: Use with caution for severe hypertension during hospitalization as they may increase AKI risk in most patients 5

• Long-term management: Once AKI resolves, reassess antihypertensive regimen and consider reintroduction of ACE inhibitors or ARBs if appropriate, especially for patients with albuminuria 3

Common Pitfalls to Avoid

1. Continuing nephrotoxic medications during AKI episodes (NSAIDs, aminoglycosides, contrast media) 3

2. Aggressive blood pressure lowering leading to hypoperfusion and worsening kidney function

3. Using ACE inhibitors or ARBs during acute kidney injury episodes 3

4. Combining ACE inhibitors and ARBs which increases risk of hyperkalemia and AKI without additional cardiovascular benefit 3

5. Using diuretics to treat AKI except for managing volume overload 3