Theoretical biology & medical modelling
-
Theor Biol Med Model · Jul 2007
Clinical TrialThe relationship between twitch depression and twitch fade during neuromuscular block produced by vecuronium: correlation with the release of acetylcholine.
Train-of-four stimulation pattern following the administration of non-depolarizing neuromuscular blocking drugs reveals fade on successive contractions. Fade is caused by the release of fewer acetylcholine molecules by the fourth (A4) than by the first stimulus (A1). The current study was conducted to define the relationship between the clinically observed fade and the simulated decline in acetylcholine release (A4/A1) that would be necessary to produce it. ⋯ The hysteresis in the fade between onset and offset appears to be caused by a delayed decrease of A4/A1 as compared with the decrease in T1. Tentative estimates of the decrease in A4/A1 during fade produced by vecuronium are offered. However, the validity of these estimates is dependent on the validity of the assumptions made in simulations.