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The impact of oral premedication with midazolam on respiratory function in children

Britta S von Ungern-Sternberg1, Thomas O Erb, Walid Habre

  • 1Department of Anesthesia, Princess Margaret Hospital for Children, Perth, Australia. britta.regli-vonungern@health.wa.gov.au

Anesthesia and Analgesia
|May 19, 2009
PubMed

Insights

Oral midazolam premedication in children causes mild respiratory changes, including decreased functional residual capacity (FRC) and increased ventilation inhomogeneity. Anesthesiologists should monitor respiratory function closely, especially in at-risk children.

Area of Science:

  • Pediatric Anesthesiology
  • Respiratory Physiology

Background:

  • Midazolam premedication is common in pediatric anesthesia to reduce anxiety.
  • Its muscle relaxant properties may affect respiratory function.
  • Assessing these effects on lung function is crucial for patient safety.

Purpose of the Study:

  • To evaluate the impact of oral midazolam premedication on respiratory parameters in children.
  • To assess changes in functional residual capacity (FRC), ventilation homogeneity (lung clearance index - LCI), and respiratory mechanics.

Main Methods:

  • SF(6) multibreath washout technique used to measure FRC and LCI.
  • Forced oscillation technique employed to determine respiratory resistance and elastance.
  • Measurements taken in 18 children (3-8 years) before and after midazolam administration.

Main Results:

  • A statistically significant decrease in FRC (6.5%) and increase in LCI (7.8%) were observed.
  • Respiratory resistance increased by 7.4% and elastance by 9.2%.
  • All observed changes were significantly correlated.

Conclusions:

  • Low-dose oral midazolam causes mild, transient respiratory alterations in children with healthy lungs.
  • Anesthesiologists must consider potential exacerbation of respiratory compromise in high-risk pediatric patients.
Abstract

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