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Pharmacokinetics of remifentanil in anesthetized pediatric patients undergoing elective surgery or diagnostic

A K Ross1, P J Davis, G L Dear Gd

  • 1Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina, USA.

Anesthesia and Analgesia
|December 1, 2001
PubMed

Insights

Remifentanil pharmacokinetics in children show age-related changes in clearance and distribution, but not half-life. This ultra-short-acting opioid, remifentanil hydrochloride, is rapidly eliminated, differing from other opioids.

Area of Science:

  • Pharmacology
  • Pediatric Anesthesiology
  • Pharmacokinetics

Background:

  • Remifentanil hydrochloride is an ultra-short-acting opioid metabolized by esterases.
  • Understanding remifentanil pharmacokinetics in pediatric populations is crucial for safe anesthesia.

Purpose of the Study:

  • To characterize the pharmacokinetics of remifentanil after a single-bolus dose in children aged 0 to 18 years.
  • To determine the hemodynamic profile of remifentanil in pediatric patients.

Main Methods:

  • Forty-two children (0-18 yr) received a 5 microg/kg remifentanil bolus.
  • Pharmacokinetic analysis using mass spectroscopy on arterial blood samples.
  • Hemodynamic measurements were recorded post-infusion.

Main Results:

  • Volume of distribution was largest in infants (<2 mo) and decreased with age.
  • Clearance was more rapid in infants (<2 yr) compared to older children and adolescents.
  • Half-life remained consistent across all age groups (3.4-5.7 min).
  • Hypotension occurred in 17% of subjects.

Conclusions:

  • Remifentanil exhibits age-related changes in clearance and volume of distribution in children.
  • Unlike other opioids, young infants show increased remifentanil clearance.
  • A 5 microg/kg remifentanil bolus may induce hypotension in anesthetized children.
Abstract

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