Related Experiment Videos
Ventilation, ventilatory carbon dioxide and hormonal response during halothane anaesthesia and surgery in children
Insights
A higher dose of midazolam improved sedation and reduced stress hormones in children undergoing surgery. While it slightly decreased ventilation, the overall response to carbon dioxide remained adequate post-operation.
Area of Science:
- Pediatric Anesthesiology
- Pharmacology
- Pediatric Surgery
Background:
- Midazolam is a common sedative used in pediatric anesthesia.
- Understanding its dose-dependent effects on ventilation and stress response is crucial for patient safety.
Purpose of the Study:
- To investigate the influence of two different intramuscular midazolam doses (0.1 mg/kg vs. 0.2 mg/kg) on sedation, ventilation, ventilatory response to carbon dioxide, and hormonal stress response in children.
- To compare the effects of midazolam premedication during halothane anesthesia for minor surgical procedures.
Main Methods:
- A study involving 14 intubated, spontaneously breathing children (8.3-25.6 kg) divided into two groups receiving different midazolam doses.
- Measurement of catecholamines, ACTH, and cortisol levels at various time points: post-induction, during anesthesia, during surgery, and post-surgery.
- Assessment of sedation, ventilation parameters (VE, respiratory rate), and ventilatory response to carbon dioxide.
Main Results:
- The higher midazolam dose (0.2 mg/kg) resulted in better sedation and lower plasma catecholamine levels during anesthesia.
- A dose-dependent depression of the ventilatory response to carbon dioxide was observed.
- Hormone concentrations did not differ between groups during surgery or recovery, but all increased significantly in recovery compared to undisturbed anesthesia.
Conclusions:
- Higher dose midazolam (0.2 mg/kg) offers improved sedation and attenuated hormonal stress response in pediatric patients.
- While a dose-dependent decrease in ventilatory response to CO2 occurs, it remains clinically adequate post-surgery.
- Midazolam premedication influences sedation and stress response, with ventilatory effects being dose-dependent but manageable.
Abstract:
In 14 intubated, spontaneously breathing children with body weight (bw) ranging from 8.3 to 25.6 kg, the influence of midazolam 0.1 mg kg-1 i.m. (group M0.1, n = 7) and 0.2 mg kg-1 i.m. (group M0.2, n = 7) as premedication, on sedation, ventilation, ventilatory response to carbon dioxide and hormonal stress response was studied in connection with minor surgical procedures during halothane anaesthesia. The concentrations of catecholamines, ACTH and cortisol were measured immediately after induction, during undisturbed anaesthesia, during surgery and 15 min after the end of the surgical procedure. Sedation was better and plasma catecholamine concentrations during undisturbed anaesthesia were less in children receiving the larger dose of midazolam. During surgery and in recovery there were no differences in hormone concentrations. In recovery, the concentrations of all hormones were significantly greater compared with during undisturbed anaesthesia. During surgery, VE and respiratory rate were somewhat lower in group M0.2 while E' CO2 was similar. A dose dependent depression of the response to carbon dioxide was found. However, clinically, the ventilatory response to carbon dioxide after surgery was considered to be adequate in both groups.