This is the theoretical volume into which a drug is distributed. This is true most notably of valproic acid and acetylsalicylic acid. So a drug that may be highly protein bound in therapeutic dosing may be much less so in overdose, as plasma proteins become saturated. A person only has so much available plasma protein (e.g. Highly dialyzable toxins should be less than 80% protein bound. Examples include phenytoin, warfarin, Amanita toxin, sulfonylureas, and many antibiotics. Because proteins are so large, any drug that is primarily bound to plasma proteins will simply not be removed. Most drugs are under this cutoff – but proteins, heparin, monoclonal antibodies, and a few others are not. 2 What does this mean? See table 1 for a list of common substances and their molecular weight. This depends on the membrane pore size, but generally highly dialyzable toxins should weigh less than 15,000 Daltons. membrane materials, surface area, etc.), it is primarily determined by several characteristics of the substance itself: Although there are features of the extracorporeal circuit which may alter a substance’s dialyzability (e.g. This refers to the capacity of a drug or toxin to be removed by a dialysis membrane. 1īut when is it appropriate? What method should be used? How long should it continue? What are all of those doodads on the dialysis machine?įirst, let’s define 2 key concepts: Dialyzability and Clearance. A therapy in a shared domain, nephrology and toxicology combine expertise to identify and treat patients for whom this therapy may save a life. Hemodialysis has long been in the toxicology toolbox for overdoses in which removal of the toxin is effective and life-saving. In the midst of resuscitation, you page the nephrologist. During your initial evaluation, she has a seizure and develops a wide-complex tachycardia, which degenerates into pulseless arrest. Her triage vitals are notable for a HR of 160 bpm, and BP of 92/60 mmHg.

Dialyze This – Extracorporeal Removal Techniques for the Poisoned Patient CaseĪ 26-year-old woman presents with palpitations after intentionally ingesting 180 tablets (36 g) of caffeine in a suicide attempt.

Qtox features