A nurse is caring for a patient with acute kidney injury (AKI) who has been receiving continuous renal replacement therapy (CRRT) for 24 hours. Which assessment finding would be the priority concern requiring immediate intervention?

Immediate Actions for Sudden Circuit Clotting:

1. Stop the pump immediately to prevent dislodging a clot into the patient's circulation.
2. Clamp both the arterial and venous lines to isolate the circuit and prevent air embolism or blood loss.
3. Do not flush the clotted circuit; flushing can push the clot into the patient.
4. Assess the patient's vital signs and hemodynamic stability, as abrupt cessation of therapy can cause fluid shifts.
5. Prepare to replace the entire extracorporeal circuit (filter and tubing set) to resume therapy as ordered.
6. Document the event, including circuit pressures prior to clotting, estimated blood loss, and patient response.

Preventive Strategies:

• Ensure adequate anticoagulation as prescribed (e.g., citrate or heparin).
• Monitor circuit pressures (arterial, venous, transmembrane) closely for trending increases indicating early clot formation.
• Maintain adequate blood flow rate; avoid frequent pump stops.
• Inspect the filter and drip chambers regularly for dark streaks or clot formation.

Clinical Reasoning: A clotted CRRT circuit is a medical emergency because it results in complete cessation of renal replacement therapy and can lead to significant blood loss (the entire circuit volume is lost). This takes priority over managing expected AKI symptoms like oliguria or even moderate hyperkalemia, which can be addressed concurrently but do not carry the same immediate risk of acute therapy failure and blood loss.