Ketofol simulations for dosing in pediatric anesthesia.

Area of Science:

• Anesthesiology
• Pharmacology
• Pediatric Medicine

Background:

• Ketofol (ketamine-propofol mixture) is increasingly used for procedural sedation and anesthesia.
• Optimal ketofol ratios and infusion rates for pediatric anesthesia are not established.
• Understanding dose-response relationships is crucial for safe administration.

Purpose of the Study:

• To determine optimal ketofol dosing regimens for pediatric anesthesia.
• To evaluate the impact of different ketamine-propofol ratios and infusion rates on recovery time.
• To ensure adequate anesthesia while minimizing prolonged sedation.

Main Methods:

• Pharmacokinetic-pharmacodynamic modeling was used to simulate drug concentrations and effects.
• Simulations explored various ketamine-propofol ratios (1:1 to 10:1) and infusion rates.
• The primary endpoint was the predicted 50% probability of return of response after infusion (P(50)) in a healthy child.

Main Results:

• Higher ketamine ratios prolonged P(50), indicating longer recovery.
• Adjusting infusion rates significantly reduced P(50) across different ratios.
• Specific rates were identified to achieve P(50) of ~20 min for 30-min anesthesia and ~60 min for 1.5-h anesthesia.

Conclusions:

• Ketamine addition to propofol prolongs recovery unless infusion rates are reduced.
• Recommended optimal ratios: 1:5 for 30-min and 1:6.7 for 90-min anesthesia.
• These ratios may enhance antiemetic effects and reduce postoperative nausea.