Failure to recruit patients further

Purpose of this study is to evaluate the short-term hemodynamic effects of changes in blood flow rates in critically ill patients receiving continuous renal replacement therapy.

Inclusion Criteria:

• Age 18-89
• Acute renal failure or end-stage renal disease necessitating CRRT
• Admitted to the MICU service
• If on vasopressor/inotropic agent, norepinephrine as only intravenous pressor
• If on vasopressor/inotropic agent, at stable pressor dose for at least four hours
• If on IV fluids, stable dose of crystalloids <= 100cc/hour and is not receiving colloids for 4 hours or more prior to initiation of CRRT
• Mean arterial pressure (MAP) >= 65
• Arterial catheter present for continuous blood pressure monitoring
• CRRT duration of 48 hours or less using NxStage System One dialysis system
• successfully tolerated CRRT for at least 4 hours without clotting or hemodynamic instability
• no other procedures, blood products transfusion, or additional medication administration are anticipated during the study period

Exclusion Criteria:

• listed for organ transplant
• atrial fibrillation, other irregular heart rhythm, unstable arrhythmia
• need for more than one intravenous vasopressor agent
• intravenous vasopressor/inotropic agent other than norepinephrine (ie dobutamine, dopamine, vasopressin, epinephrine)
• therapeutic anticoagulation being administered
• known acute myocardial infarction as defined by elevated troponin along with a documented clinical diagnosis during current hospitalization
• known acute stroke, intracerebral hemorrhage, intracranial mass effect, or elevated intracranial pressure within the last 30 days.
• dialysis catheter malfunction and unable to maintain target blood flow rate
• fluid removal (ultrafiltration) rate > 100mL/hour

40 minutes