Renal Replacement Therapy

Renal Replacement Therapy
Trauma Conference
By:Amanda Wheeler, MD

Principles
4 Main Modalities in ICU
* HD
* PD
* CVVH
* CVVHD

Definition of Terms
* SCUF- Slow Continuous Ultrafiltration
* CAVH- Continuous Arteriovenous Hemofiltration
* CAVH-D- Continuous Arteriovenous Hemofiltration with Dialysis
* CVVH- Continuous Venovenous Hemofiltration
* CVVH-D- Continuous Venovenous Hemofiltration with Dialysis

Indications for Continuous Renal Replacement Therapy
* Volume Overload
* Electrolyte Imbalance
* Uremia
* Acid-Base Disturbances
* Drugs

Hemodialysis vs Hemofiltration Membrane
The hemofiltration membrane consists of relatively straight channels of ever-increasing diameter that offer little resistance to fluid flow.
Hemodialysis membranes contain long, tortuous inter-connecting channels that result in high resistance to fluid flow.
Hemodialysis allows the removal of water and solutes by diffusion across a concentration gradient.

Hemodialysis
* maximum solute clearance
* best tx for severe hyper-K+
* ready availability
* limited anti-coagulation time
* bedside vascular access
* hemodynamic instability
* hypoxemia
* rapid fluid + solute shifts
* complex equipment
* specialized personnel

advantages
disadvantages

Peritoneal Dialysis
* simple to set up + perform
* easy to use
* hemodynamic stability
* no anti-coagulation
* bedside peritoneal access
* unreliable ultrafiltration
* slow fluid + solute removal
* drainage failure, leakage
* catheter obstruction
* respiratory compromise
* hyperglycemia
* peritonitis

advantages
disadvantages

CVVHD vs CVVH
CVVH
* 1. near-complete control of the rate of fluid removal (i.e. the ultrafiltration rate)
* 2. precision and stability
* 3. electrolytes or any formed element of the circulation, including platelets or red or white blood cells, can be removed or added independent of changes in the volume of total body water

CVVH
* easy to use in ICU
* rapid electrolyte correction
* excellent solute clearances
* rapid acid/base correction
* controllable fluid balance
* tolerated by unstable patients
* early use of TPN
* bedside vascular access routine
* systemic anticoagulation *
* citrate anticoagulation new
* frequent filter clotting
* hypotension

advantages
disadvantages

Renal Replacement Therapy.ppt