P. Schultz et al., Onset and duration of action of rocuronium - from tracheal intubation, through intense block to complete recovery, ACT ANAE SC, 45(5), 2001, pp. 612-617
Citations number
17
Categorie Soggetti
Aneshtesia & Intensive Care","Medical Research Diagnosis & Treatment
Background: The primary objective of this study was to establish the relati
on between the post tetanic count (PTC) and the time to reappearance of the
first response (T-1) in train-of-four (TOF) nerve stimulation following ro
curonium 0.6 mg/kg, 0.9 mg/kg, and 1.2 mg/kg. The secondary objective was t
o evaluate the intubation conditions after 1 min.
Methods: One hundred and eight patients were randomised to one of three dos
es of rocuronium: 0.6, 0.9 or 1.2 mg/kg. Tracheal intubation was performed
at 60 s by a blinded investigator During propofol, fentanyl, midazolam anae
sthesia the neuromuscular block was monitored by mechanography using TOF st
imulation every 12 s. At 6 min intervals, a tetanic stimulation (50 Hz) was
applied for 5 s preceded and followed by a 30 s period of 1 Hz stimulation
until the reappearance of T-1.
Results: There was a significant difference in recovery following the high
dose and the two lower doses. The relation between time (min) to reappearan
ce of T-1 (t) and PTC can be expressed as follows: t((0.6 and 0.9 mg/kg)(mi
n)) = 18.8-6.46 root PTC and t((1.2 mg/kg)(min)) = 26.1-9.12 root PCT. T-1
was seen at a mean PTC level of 8 or 9 in all three soups. The intubation c
onditions were graded as excellent or good in all patients except in two pa
tients following the 0.6 mg/kg dose of rocuronium.
Conclusion: The PTC method can be used to predict the time to first respons
e to TOF nerve stimulation during intense rocuronium induced neuromuscular
blockade. The relation between PTC and the time to T-1 was prolonged after
1.2 mg/kg compared with 0.6 mg/kg and 0.9 mg/kg. No further improvement in
intubation conditions at 60 s was evident by increasing the rocuronium dose
from 0.9 mg/kg to 1.2 mg/kg.