A Mystery Case of Blood Leak Alarm Triggering
The mandatory blood leak detector (BLD) in a hemodialysis machine protects patients from harm by automatically shutting down the instrument if a leak is detected. Mechanical issues such as air bubbles or grease depositis may falsely activate the BLD alarm. Hemolysis has also been shown to activate the BLD . Hydroxocobalmin is known to interfere with the blood leak detector, causing a false alarm, which leads to the inability to perform dialysis.
A 68-year-old male with end stage renal disease on intermittent hemodialysis was admitted to the hospital after presenting with weakness and fatigue. He was previously scheduled to have outpatient coronary artery bypass grafting due to severe coronary artery disease. Patient was found to have aortic valve infective endocarditis and underwent urgent aortic valve replacement along with coronary artery bypass grafting. His postoperative course was complicated by hypotension, resulting in acute kidney injury requiring hemodialysis. He initially received intermittent hemodialysis with a 2008K Fresenius dialyzer instruments with adequate tolerance.
On post-operative day 10, BLD interrupted dialysis as the dialysate effluent became read in color. Work up for hemolysis returned negative. Hemoglobin remained stable. Hemodialysis was attempted twice again using different 2008K Fresenius dialyzer instruments and the BLD alarm interrupted dialysis on each occasion. We bypassed the BLD alarms by testing the dialysate fluid for leaks every 15 minutes and by continuously resetting the alarm.
Review of administered medications revealed that the patient received 5 mg of hydroxocobalmin (Vitamin B12A) intravenously on the day preceding the first blood leak alarm for vasoplegia syndrome. Rifampin was included in the patient’s antibiotic regimen for infective endocarditis and is known to cause reddish discoloration of bodily fluids. Rifampin was discontinued but did not resolve the issue. The BLD no longer alarmed two days following discontinuation of hydroxocobalmin. Rifampin was restarted without any additional blood leak alarms.
This case highlights the importance of recognizing other etiologies of BLD alarms, especially when mechanical issues and hemolysis have been ruled out. It is important to recognize hydroxocobalmin as a cause for BLD false alarms. Fleishman issued a black box warning several months after our case.
Maditz R, Hakim S, *Lohani S, Zarouk S. A mystery case of blood leak alarm triggering. American College of Physicians (ACP) Michigan Chapter Scientific Meeting, Acme, MI, October 19-22, 2017.