Related Experiment Videos
Efficacy of an epidural test dose in children anesthetized with halothane
J Desparmet1, J Mateo, C Ecoffey
1Department of Anesthesiology, Hopital de Bicêtre, Université Paris-Sud, Le Kremlin-Bicêtre, France.
Insights
Atropine improves the reliability of intravenous lidocaine test doses in children receiving halothane anesthesia. However, this test dose does not guarantee the detection of all intravascular injections.
Area of Science:
- Anesthesiology
- Pediatric Anesthesia
- Pharmacology
Background:
- Epidural anesthesia is common in pediatric procedures.
- Accurate test doses are crucial to prevent accidental intravascular injection.
- Lidocaine with epinephrine is a common test dose, but its reliability in children needs evaluation.
Purpose of the Study:
- To assess the reliability of an intravenous lidocaine with epinephrine test dose in children.
- To determine the effect of atropine on the reliability of this test dose.
- To evaluate hemodynamic changes indicative of intravascular injection.
Main Methods:
- Sixty-five children (1 month to 11 years) undergoing anesthesia with halothane and nitrous oxide were studied.
- Four groups received varying combinations of atropine and an intravenous test dose of lidocaine with or without epinephrine.
- Heart rate and blood pressure were monitored following the test dose.
Main Results:
- Intravenous test doses containing epinephrine, especially with prior atropine administration, increased heart rate and blood pressure.
- Atropine improved the detectability of the test dose's effects on heart rate.
- Test doses without epinephrine did not produce significant hemodynamic changes.
- Some intravascular injections were still not reliably detected, even with atropine.
Conclusions:
- Atropine (10 micrograms/kg) enhances the reliability of an intravenous lidocaine with epinephrine test dose in pediatric patients under halothane anesthesia.
- The test dose is not foolproof and does not ensure complete detection of all intravascular injections.
- Further research may be needed to optimize test dose protocols in pediatric anesthesia.
Abstract:
The effect of an intravenous (iv) injection of lidocaine with epinephrine was studied to determine if such a test dose would cause a reliably detectable increase in heart rate and systemic blood pressure in children anesthetized with halothane and nitrous oxide. The effect of the injection of atropine before the test dose on these parameters was also determined. Sixty-five children 1 month to 11 yr of age and weighing 3.9-35 kg were studied. The children were assigned to one of four groups, each of which was anesthetized with 1% halothane and 50% nitrous oxide. Group 1 (n = 20) received 10 micrograms/kg atropine followed 5 min later by an iv dose of 0.1 ml/kg 1% lidocaine with 1/200,000 epinephrine (0.5 micrograms/kg) to simulate an intravascularly administered epidural test dose. Group 2 (n = 21) was identical to group 1 but did not receive atropine prior to the simulated intravascular test dose. Groups 3 (n = 12) and 4 (n = 11) were identical to groups 1 and 2, but the simulated intravascular test dose did not contain epinephrine: group 3 received atropine prior to the test dose and group 4 did not. The simulated intravascular test dose increased heart rate in group 1 (with atropine) at each time period from 15 to 120 s, but only at 45 and 60 s in group 2 (without atropine). Following the iv test dose, 6 of 21 children in group 2 had an increase in heart rate of less than 10 beats/min, while only one child in group 1 had an increase in heart rate of less than 10 beats/min. Intravenous test doses that did not contain epinephrine (groups 3 and 4) had no effect on heart rate or blood pressure. Atropine, 10 micrograms/kg, improves the reliability of an epidural test dose in children anesthetized with halothane and nitrous oxide but does not ensure total reliability in detecting an intravascular injection.