Cardiovascular changes during halothane induction in children.

Area of Science:

• Pediatric Anesthesiology
• Cardiovascular Physiology

Background:

• Halothane induction in children is known to cause bradycardia and myocardial depression, potentially compromising organ perfusion.
• Arrhythmias are a documented risk with halothane anesthesia.
• Limited regional data exists on cardiovascular changes during halothane induction in pediatric patients.

Purpose of the Study:

• To investigate the cardiovascular changes associated with halothane induction in children.
• To determine the incidence of arrhythmias following halothane induction in this pediatric population.

Main Methods:

• A study involving 90 pediatric patients (6 months to 12 years) classified as ASA I-II.
• Premedication with oral promethazine (1mg/kg) was administered to children over one year of age.
• Anesthesia was induced using incremental halothane (up to 3%) in 33% oxygen and nitrous oxide.

Main Results:

• Halothane induction caused a significant decrease in systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) in all patients (p < 0.005).
• Heart rate significantly decreased post-induction in children older than one year (p < 0.05).
• Arrhythmias occurred in 3.3% of patients; bradycardia was not observed. Hypotension (8.8%) and laryngeal spasm (2.2%) were noted complications.

Conclusions:

• Halothane induction in children leads to significant reductions in heart rate and blood pressure.
• Bradyarrhythmias appear to be uncommon when promethazine premedication is used in pediatric patients undergoing halothane anesthesia.