Diagnosis, Treatment, and Prevention of Hemodialysis Emergencies

Abstract

Given the high comorbidity in patients on hemodialysis and the complexity of the dialysis treatment, it is remarkable how rarely a life-threatening complication occurs during dialysis. The low rate of dialysis emergencies can be attributed to numerous safety features in modern dialysis machines; meticulous treatment and testing of the dialysate solution to prevent exposure to trace elements, toxins, and pathogens; adherence to detailed treatment protocols; and extensive training of dialysis staff to handle medical emergencies. Most hemodialysis emergencies can be attributed to human error. A smaller number are due to rare idiosyncratic reactions. In this review, we highlight major emergencies that may occur during hemodialysis treatments, describe their pathogenesis, offer measures to minimize them, and provide specific interventions to prevent catastrophic consequences on the rare occasions when such emergencies arise. These emergencies include dialysis disequilibrium syndrome, venous air embolism, hemolysis, venous needle dislodgement, vascular access hemorrhage, major allergic reactions to the dialyzer or treatment medications, and disruption or contamination of the dialysis water system. Finally, we describe root cause analysis after a dialysis emergency has occurred to prevent a future recurrence.

Keywords: Air; Artificial; Clinical Protocols; Dialysis Solutions; Embolism; Emergencies; Hemolysis; Humans; Hypersensitivity; Kidneys; Needles; Pharmaceutical Solutions; Recurrence; Root Cause Analysis; Trace Elements; Water; air embolism; dialysis disequilibrium; hemolysis; renal dialysis.

Figure 1.

Venous air embolism may arise from 4 possible areas of air entry into the dialysis circuit. Schematic diagram of a hemodialysis circuit depicting four possible areas of air entry. (1) A broken or loose luer connection between the arterial needle and the tubing can result in air entry, because this segment has negative intraluminal pressure. (2) A hole in the arterial tubing can suck air into the arterial line. (3) Air entry can occur during administration of anticoagulation or saline. (4) Inadequate priming can result in air entry from the dialyzer or dialysis tubing. A crack in the venous bloodline will not cause air entry due to the positive intraluminal pressure. Air entering the circuit presents to the venous air trap and forms foam/bubble at the top of blood level. As soon as the blood level in the venous air trap chamber falls below the air detector level, it immediately triggers an alarm and stops blood flow. As a consequence, venous air embolism occurs due to human error.

Figure 2.

Schematic diagram illustrating an approach to evaluation of a suspected case of hemolysis during hemodialysis (HD) and its root cause analysis to prevent future episodes. LDH, lactate dehydrogenase.

Figure 3.

Flow chart of possible causes of allergic or allergic-like reactions during hemodialysis. Similar symptoms could also be caused by other etiologies, like endotoxin back filtration causing pyrogenic reaction, hemolysis, and rarely, air embolism. Heparin can cause anaphylaxis or anaphylactoid associated with positive heparin–induced thrombocytopenia (HIT) antibodies. Blood products, antibiotics, and other medications used with dialysis may also cause allergic reaction. Intravenous iron may cause a reaction due to IgE-mediated or complement activation–related pseudoallergy (CARPA); at-risk patients have history of atopy, faster infusion, and possible iron dextran exposure than iron sucrose. Ethylene oxide may bind to HSA and act as a hapten to induce an allergic reaction. Although an allergic reaction to synthetic biocompatible dialyzers is rare, it has been reported. A dialyzer with different housing compound or modified cellulose dialyzer may be considered if other causes are ruled out. Occasionally, measuring tryptase and IgE levels may be helpful; additional immunoassays and prick testing may be undertaken after consultation with an allergist. ACEi, angiotensin–converting enzyme inhibitor; AN69, acrylonitrile; HSA, human serum albumin; IV, intravenous; PAN, polyacrylonitrile.

Figure 4.

An arteriovenous graft with evidence of thin shiny surface (arrow) and superficial ulceration (arrow head) over a pseudoaneurysm.

Figure 5.

A basic scheme for root cause analysis (RCA) after an adverse event related to hemodialysis (HD).