Can hemodialysis be avoided in selected patients with significant serum levels of ethylene glycol?

May 30, 2012, 11:47 am

★★★☆☆

Ethylene Glycol Elimination Kinetics and Outcomes in Patients Managed Without Hemodialysis. Levine M et al. Ann Emerg Med 2012 Jun;59:527-531.

Abstract

It is now generally accepted that patients who have ingested ethylene glycol can be managed with fomepizole alone if they do not have significant metabolic acidosis and they do not have renal insufficiency. This study looked retrospectively at a non-randomized cohort of 40 such patients to determine the kinetics of ethylene glycol after treatment with fomepizole, as well as clinical outcomes.

In these patients, median peak ethylene glycol level was 127 mg/dl (range, 40-635 mg/dl). Initial pH ranged from 7.29-7.43, and initial anion gap from 4-29.  One patient had an asymptomatic bump in serum creatinine level that resolved without hemodialysis.  All patients recovered. The mean elimination half-life for ethylene glycol was 14.2 hours (95% confidence interval, 13.1-15.3 hours). There is no indication in the data how long these patients needed to remain on fomepizole.

The authors conclude that:

In selected patients with acute ethylene glycol toxicity (e.g., those with normal renal function and without severe metabolic acidosis), the use of fomepizole without adjunctive hemodialysis appears to be safe.

Some important points to keep in mind when reading this paper:

  1. If a patient who has ingested ethylene glycol comes in with significant metabolic acidosis, this indicates that toxic metabolites have already accumulated, and hemodialysis should be considered both to remove the metabolites and help correct acidosis.
  2. If an ethylene glycol toxic patient has renal failure, the elimination half-life of the toxic alcohol would be prolonged, and hemodialysis should be considered to accelerate elimination.
  3. The findings and conclusions of this paper do not apply to methanol, which has a significantly longer elimination half-life  after fomepizole treatment (approximately 54 hours), making it less practical and cost-effective to avoid hemodialysis by relying on fomepizole alone to treat patients with significant levels, even in the absence of metabolic acidosis or renal failure.

 

Comments are closed.