CRRT Basics

Starting Treatment

So, the nephrologist placed orders for CRRT; what will you need? First things first, access needs to be established. The patient will need a double lumen dialysis catheter.

Fistulas are common for established dialysis patients but cannot be used with CRRT. This is because it is pump-driven and incorporates venovenous extracorporeal circuits. There is a red and a blue line, but it will both be venous and should never be arterial. Once the line is established, it needs to be anticoagulated as soon as it is inserted. The amount of required heparin will be labeled on each port hub. CRRT machine orders will be given by the nephrologist and can be adjusted during the treatment. Patients will either run with a positive, negative, even, or zero fluid balance. Blood flow rate can be adjusted to help prevent clotting, and dialysate rate is usually calculated depending on patient weight and electrolytes. Lab orders and ABGs are followed based on physician preference, patient condition, and/or for any acute change. 

Complications

Clotting is the #1 complication during CRRT, whether it is the circuit clotting or the line itself clotting off. Circuit clotting needs to be closely monitored for and anticipated during the treatment. The bedside nurse should always have saline flushes and heparin (or the anticoagulant ordered) within reach if the machine decides to clot off and stop cycling the blood. If the  machine stops  cycling and appears to be trying to clot, the patient’s blood should be returned and therapy discontinued with the current circuit. Each circuit can hold approximately 150-250 mL blood, which can add up, especially if circuits are replaced 2-3 times a shift.

Other complications the nurse should be aware of and aim to prevent include but are not limited to, infections, bleeding, hypotension, electrolyte imbalances, All of these complications need to be monitored closely and the bedside nurse should utilize the multiple services consulted for the patient for optimal prevention and treatment. Depending on the institution, infectious disease, Heme/Onc and GI/GU may be following the patient as well as Critical Care and Nephrology.