Continuous arteriovenous hemofiltration: an alternative to hemodialysis

Area of Science:

• Nephrology
• Critical Care Medicine

Background:

• Continuous arteriovenous hemofiltration (CAVH) was developed for hemodynamically unstable patients with acute renal failure.
• CAVH is now utilized for fluid overload and acid-base disturbances in conditions like pulmonary edema, heart failure, and septic shock.
• It is beneficial in oliguric states requiring large fluid volumes for nutrition or medications.

Purpose of the Study:

• To introduce the procedure of continuous arteriovenous hemofiltration (CAVH).
• To review the application of CAVH in managing acute renal failure and related complications.
• To compare CAVH with hemodialysis in terms of mechanism, benefits, and limitations.

Main Methods:

• CAVH utilizes the patient's mean arterial pressure to drive ultrafiltration across a hemofilter membrane.
• Fluid and uremic toxins are removed via slow, continuous ultrafiltration.
• Membrane materials allow removal of plasma water and non-protein-bound solutes (<10,000 MW).

Main Results:

• CAVH avoids hypotension, muscle cramps, and disequilibrium syndrome associated with hemodialysis.
• It permits increased fluid administration for nutrition and medications without restriction.
• Heparin is often required to prevent clotting, potentially increasing hemorrhage risk in some patients.

Conclusions:

• CAVH is a valuable tool for managing acute renal failure, fluid overload, and acid-base disturbances.
• Its continuous, slow ultrafiltration offers a safer alternative to hemodialysis for unstable patients.
• CAVH facilitates aggressive fluid resuscitation and nutritional support in critical care settings.