Continuous Renal Replacement Therapy (CRRT)

In the ICU you may have patients that require CRRT therapy.

Types of CRRT

SCUF (slow, continuous, ultrafiltration)

Rate: 100-300 mL.hr

Function: fluid removal

Nursing considerations: may require anticoagulation

CVVH (continuous venovenous hemofiltration)

Rate: 35 mL/kg/hr

Function: Fluid removal, solute removal by convection

Nursing considerations: fluid pre-dilution or replacement required

CVVHD (continuous venovenous hemodialysis)

Rate: 35 mL/kg/hr

Function: Fluid removal, solute removal by diffusion

Nursing considerations: dialysate solution is required

CVVHDF (continuous venovenous hemodiafiltration)

Rate: Ultrafiltration is limited by the amount of pre/post-dilution or dialysate fluid infused

Function: Fluid removal, solute removal by convection and diffusion

Nursing considerations: fluid pre-dilution or replacement required, dialysate required

Requirements: Venous access for SCUF, CVVH, CVVHD, and CVVHDF. A blood pump, a filter, and therapy fluid (dialysate, pre-dilution, or post-dilution)

Specific Indications: Fluid overload unresponsive to diuretics, electrolyte imbalance, drug overdose, inability to tolerate hemodialysis, acute or chronic renal failure in a hemodynamically unstable patient, can also be used in sepsis, lactic acidosis, heart failure, multi-organ dysfunction, hepatic failure, or rhabdomyolysis.

Contraindications: Lack of venovenous access, rapid treatment required, coagulopathy.

Advantages: Removes solutes gradually, Decreased risk of hemodynamic instability,

Disadvantages: The patient has to be in bed if access is in the femoral site or is unstable, complicates dosing of medications that are dialyzable.

Complications: Hypotension, hypovolemia, hypothermia, electrolyte imbalance of potassium magnesium calcium and phosphorus, acid-base imbalances, access complications to include infection, clotting and bleeding, hemorrhage related to anticoagulation disruption of filter or tubing, and air embolism.