What is the treatment for acute on chronic renal disease?

Treatment of Acute on Chronic Renal Disease

The treatment of acute on chronic renal disease should focus on avoiding nephrotoxic medications, personalizing drug selection based on renal function, maintaining appropriate fluid balance, and considering renal replacement therapy when necessary. 1, 2

Medication Management

Nephrotoxic Medication Avoidance

• Avoid nephrotoxic medications whenever possible, especially when multiple nephrotoxic agents would be used concurrently 1, 2
• Discontinue medications that may be contributing to kidney injury:
  • ACE inhibitors and ARBs should be temporarily discontinued, especially in setting of hypovolemia 1
  • NSAIDs should be strictly avoided 1, 2
  • Aminoglycosides, contrast agents, and other known nephrotoxins should be avoided unless absolutely necessary 2

Drug Selection and Dosing

• Medication decisions must be guided by:
  • Current renal function and trajectory (improving or worsening)
  • Renal versus non-renal excretion of the drug
  • Potential for nephrotoxicity
  • Effect of renal disease on drug metabolites
  • Urgency of treatment 1
• Do not adjust medications based on eGFR formulas, as these are invalid when creatinine is not at steady state 2
• Maintain loading doses of antibiotics regardless of renal function, but extend dosing intervals rather than reducing doses 2
• Monitor drug levels more frequently when available 2

Fluid Management

• Fluid therapy must be individualized based on volume status assessment 3
• For hypovolemic patients:
  • Provide appropriate fluid resuscitation with isotonic crystalloids
  • Target euvolemia while avoiding fluid overload
  • Monitor for signs of fluid overload (peripheral edema, pulmonary congestion) 1, 3
• For euvolemic or hypervolemic patients:
  • Implement fluid restriction
  • Consider diuretics if not oliguric
  • Avoid positive fluid balance as it may delay recovery 1

Renal Replacement Therapy (RRT)

• Consider RRT when medical management fails to control:
  • Fluid overload unresponsive to diuretics
  • Severe electrolyte abnormalities (hyperkalemia)
  • Metabolic acidosis
  • Uremic symptoms 1
• RRT modality selection considerations:
  • Hemodynamic stability (continuous therapies preferred for unstable patients)
  • Fluid removal goals
  • Solute clearance needs 1
• RRT-related factors that may affect recovery:
  • Maintain hemodynamic stability during treatments
  • Avoid hypotension during dialysis
  • Avoid rapid fluid removal that may cause hypotension
  • Consider cooler dialysate temperature to minimize hypotension 1

Monitoring and Follow-up

• Regular monitoring of:
  • Renal function (creatinine, BUN)
  • Electrolytes (particularly potassium)
  • Acid-base status
  • Volume status
  • Urine output 1, 4
• Reassess medication regimen as renal function changes 2
• Monitor for complications of acute kidney disease:
  • Electrolyte abnormalities
  • Metabolic acidosis
  • Volume overload
  • Uremic symptoms 4

Common Pitfalls and Caveats

• Failing to recognize the "triple whammy" of NSAIDs, diuretics, and ACE inhibitors/ARBs which significantly increases AKI risk 1
• Inappropriate continuation of nephrotoxic medications during acute kidney injury
• Inadequate drug dosing adjustments as renal function changes
• Excessive fluid administration leading to volume overload
• Delayed initiation of renal replacement therapy when indicated
• Failure to monitor drug levels for medications with narrow therapeutic windows 1, 2
• Assuming eGFR calculations are accurate during acute changes in kidney function 2

By implementing this comprehensive approach to acute on chronic kidney disease management, focusing on medication optimization, appropriate fluid management, and timely renal replacement therapy when needed, patient outcomes can be improved with reduced morbidity and mortality.