Related Experiment Video
Updated: Oct 8, 2025
08:49
Assessing Changes in Volatile General Anesthetic Sensitivity of Mice after Local or Systemic Pharmacological Intervention
Published on: October 16, 2013
14.0K
Propofol context-sensitive decrement times in children.
James D Morse1, Luis Ignacio Cortinez2, Stephen Meneely3
1Department of Pharmacology & Clinical Pharmacology, Auckland University, Auckland, New Zealand.
Paediatric Anaesthesia
|December 31, 2021
Summary
Propofol
Area of Science:
- Pharmacology
- Anesthesiology
- Pediatric Anesthesia
Background:
- Plasma drug concentration links anesthetic dose to effect.
- Context-sensitive half-time (CSHT) correlates with recovery but may not precisely predict return to consciousness.
- Effect-site concentration is a better predictor of consciousness recovery than plasma concentration.
Purpose of the Study:
- To simulate propofol decrement times to a specific arousal concentration in children.
- To evaluate the influence of age, infusion duration, and target concentration on recovery times.
- To provide a basis for guiding post-anesthesia recovery in pediatric patients.
Main Methods:
- Simulated propofol decrement time to a target effect-site concentration of 2 µg/mL.
- Calculated decrement time to consciousness (CSTAWAKE) from a steady-state target of 3.5 µg/mL.
- Analyzed effects of age (infant to adolescent), infusion duration (15 min to 2 hours), and target concentration (3.5 vs. 6 µg/mL).
Main Results:
- CSTAWAKE ranged from 7.5 min (1-year-old, 15 min infusion) to 13.5 min (15-year-old, 2-hour infusion).
- Neonates exhibited prolonged increment times (10-18 min).
- Higher target concentrations (6 µg/mL) doubled decrement times, indicating context-sensitivity.
Conclusions:
- Propofol decrement times to arousal are influenced by age, infusion duration, and target concentration.
- Simulated times offer insights into pediatric recovery but individual variability exists.
- Understanding these decrement times can optimize anesthetic recovery protocols for children.
Related Concept Videos
01:24Parenteral Anesthetics: Overview
320
Intravenous anesthetics are drugs administered parenterally to induce anesthesia or sedation. Propofol is a widely used agent formulated as a 1% emulsion in soybean oil, glycerol, and egg phosphatide. It induces rapid anesthesia primarily due to its rapid distribution from the bloodstream to target tissues and is metabolized in the liver. However, it can cause significant pain on injection and hypertriglyceridemia. Fospropofol, a water-based prodrug of propofol, lacks these adverse effects.
320
01:29Drug Dosing: Infants and Children
24
Pediatric patient dosages diverge from adults due to disparities in body surface area, total body water, and extracellular fluid per kilogram of body weight. The dosing regimen considers the variations in pharmacokinetics and pharmacology across distinct age groups, encompassing preterm newborns, infants, young children, older children, and adolescents. Calculation of pediatric patient doses is predicated on determining body surface area, which exhibits a superior correlation with the child's...
24
01:19Depolarizing Blockers: Pharmocokinetics
403
Depolarizing blockers are administered through intravenous injection. Succinylcholine is the most common choice of depolarizing blockers in emergency clinical practices. Although they have a rapid onset, they readily diffuse away from the motor end plate into the extracellular fluid. They are metabolized by enzymes such as liver butyrylcholinesterase and plasma pseudocholinesterases. This produces a short duration of action, typically 5-10 minutes long, unlike nondepolarizing blockers, which...
403
01:24Pharmacokinetics in Pediatric Patients: Drug Metabolism
20
In pediatric care, understanding the nuances of hepatic drug metabolism is crucial, as it significantly differs from that of adults. This divergence is primarily due to the developmental stage of drug-metabolizing enzymes, which affects how medications are processed in the body. In neonates, for instance, the activity of Phase I enzymes—critical for the initial breakdown of drugs—is markedly reduced, functioning at just 20–40% of the levels seen in adults. This reduction poses...
20
01:23Pharmacokinetics in Pediatric Patients: Overview and Drug Absorption
14
Understanding the physiological differences in the pediatric population is crucial for effective pharmacotherapy. Neonates, infants, and children exhibit significant variations in gastric pH, gastric emptying time, intestinal transit time, and biliary function. These variations profoundly affect oral drug absorption, necessitating a nuanced approach to pediatric dosing.Neonates present with a unique physiological profile, having a gastric pH greater than 4 and faster and more irregular gastric...
14
01:26Pharmacokinetics in Pediatric Patients: Drug Excretion
15
In pediatric medicine, understanding the renal function and drug elimination nuances is crucial for administering safe and effective treatments. Newborns, in particular, display markedly slower renal functions than adults, profoundly affecting how drugs are cleared from their bodies. This slower drug clearance requires clinicians to extend the dosing intervals for many medications to prevent drug accumulation and toxicity while ensuring therapeutic efficacy.One key area where these adjustments...
15