Heparin-induced hyperkalemia

We have described three patients with diabetes and renal insufficiency who had hyperkalemia during heparin therapy. These cases lend support to previous findings, and emphasize the clinical importance of this entity. We believe that heparin-induced hyperkalemia is a potentially life-threatening problem that is more common than previously appreciated. We suggest that in high-risk patients (ie, those with diabetes and/or renal insufficiency) serum potassium be monitored frequently during heparin therapy.     

Heparin-induced hyperkalemia

Heparin sodium is an extremely useful medication with demonstrated benefit in a number of clinical settings. Physicians need to be aware of the potential complication of hyperkalemia, especially in patients with renal insufficiency or diabetes mellitus. Discontinuation of heparin therapy is necessary to reverse the suppression of aldosterone. If heparin is the cause, the hyperkalemia will resolve within 5 days.     

Transfusion-associated hyperkalemia

The supernatant potassium concentration [K+] of red blood cell (RBC) units is frequently much higher than normal human plasma potassium levels, especially in units nearing the end of their storage life. Clinical hyperkalemia resulting from RBC transfusions has been recognized as a transfusion complication for decades, and there have been reported cardiac arrests attributed to transfusion-associated hyperkalemia. This review summarizes the evidence surrounding RBC [K+] levels, effects of irradiation and washing on [K+], the evidence for clinical hyperkalemia and cardiac arrests resulting from transfusion, predictors of post-transfusion hyperkalemia, and their preventative strategies. Key points include: (a) the [K+] (in mmol/L) increases linearly and is approximately equal to the number of days of RBC unit storage; (b) irradiation causes a rapid increase in [K+]; (c) there is potentially sufficient potassium in the supernatant of current RBC preparations to lead to hyperkalemia with large transfusion volumes; (d) any rise in patient potassium after transfusion is usually transient due to the redistribution of the potassium load; (e) transfusion-associated hyperkalemic cardiac arrests probably do occur, although it is difficult to prove this fact conclusively; and (f) promising strategies to combat transfusion-associated hyperkalemia include RBC washing, the use of in-line potassium filters, and the use of traditional treatments for hyperkalemia such as the use of insulin.     

Extreme hyperkalemia

Hyperkalemia is a potentially fatal condition and is defined by a serum potassium level (K+) of greater than 5.5 mmol/L. The associated prevalence of cardiac arrhythmia increases directly with the degree of hyperkalemia. The danger in the majority of hyperkalemia cases is cardiac dysrhythmia, and often ventricular fibrillation or asystole is the terminating event. Although there are many previous reports addressing this threatening problem and associated therapeutic maneuvers, there have not been many previous reports citing the fatal concentration of hyperkalemia irrespective of the causes. However, it is uniformly accepted that a K+ concentration greater than 10.0 mmol/L is fatal unless urgent treatment is instituted. This report describes a case of nonfatal hyperkalemia of 14 mmol/L with intact survival and complete recovery. Potassium homeostasis is revisited, and some explanations are proffered regarding the protective mechanism against hyperkalemia, including transcellular flux, renal tubular function, and endocrine responses.     

Heparin-induced hyperkalemia

Because heparin sodium is used so frequently, physicians need to be aware of hyperkalemia, a potentially life-threatening adverse effect. In this article, Dr Edes discusses a case that typifies the clinical course and treatment of this problem.     

Beating the bangs!

ABSTRACT:

With the firework season looming, followed closely by Christmas and New Year, we must think about how our pets will react to the loud noises and bright lights. This article outlines the practical steps that owners can take to help their pets throughout the party season and, in turn, help prevent fears turning into phobias.