Related Experiment Video
Updated: Jan 31, 2026

An In Vivo Mouse Model of Total Intravenous Anesthesia During Cancer Resection Surgery
Published on: June 8, 2021
Effect of muscle relaxant on entropy during propofol anesthesia
Bo Song Kim1, Sang Ik Lee1, Sung Uk Choi1
1Department of Anesthesiology and Pain Medicine, College of Medicine, Korea University, Seoul, Korea. ysmin@korea.ac.kr.
Background:
The purpose of this study was to investigate whether muscle relaxant affect the values of Entropy, response entropy (RE) or state entropy (SE) during propofol anesthesia.
Methods:
Eighty patients (ASA I) scheduled for elective surgery under general anesthesia were randomly assigned to four groups. Anesthesia was maintained at a SE value of 80 (80 +/- 2) using target controlled infusion (TCI) of propofol. After maintaining SE 80 for 5 min, vecuronium 0.1 mg/kg was injected intravenously in group I and same volume of normal saline was intravenously injected in group II. After maintaining SE 60 for 5 min, vecuronium 0.1 mg/kg was injected intravenously in group III and same volume of normal saline was injected intravenously in group IV. The mean arterial pressure, heart rate, SE and RE were measured before anesthetic induction and up to 5 min after vecuronium or normal saline injection in each group.
Results:
SE and RE were not changed in group II, but significantly decreased in group I (P < 0.05, respectively). In group III and IV, SE and RE were not changed in both groups. There were no significant hemodynamic changes among the four groups.
Conclusions:
These results suggest that the effect of muscle relaxant on Entropy vary according to the baseline values of RE or SE during propofol anesthesia.
Related Concept Videos
Relaxation of Skeletal Muscles
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open....
Entropy
Entropy
When an ideal gas expands isothermally, the disorder in the gas increases. From the molecular perspective, the gas molecules have more volume to move around in.
Consider an infinitesimal step in the expansion, which...
Classification of Skeletal Muscle Relaxants
Peripherally acting skeletal muscle relaxants interfere with the neurotransmission at the neuromuscular end plate to induce paralysis during...
Skeletal Muscle Relaxants: Therapeutic Uses
Standard Entropy Change for a Reaction

