15733
document
The effect of use of pyridostigmine and requirement of vecuronium in patients with myasthenia gravis . CONTEXT Patients with myasthenia gravis receive pyridostigmine , an anticholinesterase agent , as a part of therapy . These patients demonstrate a heightened sensitivity towards non-depolarising muscle relaxants . Continuing pyridostigmine till the day of the surgery or omitting it on the night before surgery could provide variable results with regards to the effect of vecuronium . AIMS Myographic evaluation of a dose of vecuronium in patients with myasthenia gravis on pyridostigmine therapy . SETTING AND DESIGN A randomised , double-blind , clinical study conducted in a teaching hospital . SUBJECTS AND METHODS Medically ( oral pyridostigmine ) well-controlled adult patients with myasthenia gravis who were posted for thymectomy , were randomly divided into two groups . Patients in Group 1 received their last dose of pyridostigmine on the night before surgery while those in Group 2 received even the morning dose of the drug on the day of surgery . Neostigmine ( 1-2 mg ) intravenously was used as rescue medication . Vecuronium ( 0.01 mg/kg ) was used for intubation and muscle relaxation during trans-sternal thymectomy and its effect was reversed using neostigmine and atropine . RESULTS Fourteen patients ( 7 in each group ) belonging to both sexes were enrolled in the study . The intubating dose of vecuronium showed quicker onset time ( 155 sec or 2.7 min approx . ) and peak effect ( 99 % T1 suppression ) in patients belonging to Group 1 , and 3/7 ( 43 % ) complained of respiratory discomfort while waiting for surgery . By giving the morning dose of pyridostigmine ( Group 2 ) , an identical intubating dose of vecuronium showed relative resistance ( peak effect-97 % T1 suppression ) and delayed onset time ( 198 sec approx. ) . However , the reversal was complete at the end of surgery in both the regimens . CONCLUSIONS Omission of the pyridostigmine dose on the day of surgery predisposed patients with myasthenia gravis to the possibility of respiratory discomfort and sensitivity to vecuronium . Continued administration significantly prolonged the onset time of vecuronium and the patients required a higher dose of vecuronium .
15734
Intervention_Pharmacological
pyridostigmine
15735
Intervention_Pharmacological
vecuronium
15736
Intervention_Pharmacological
pyridostigmine
15737
Intervention_Pharmacological
anticholinesterase agent
15738
Intervention_Pharmacological
pyridostigmine
15739
Intervention_Pharmacological
vecuronium
15740
Intervention_Pharmacological
( oral pyridostigmine
15741
Intervention_Surgical
thymectomy
15742
Intervention_Pharmacological
pyridostigmine
15743
Intervention_Pharmacological
Neostigmine
15744
Intervention_Pharmacological
Vecuronium
15745
Intervention_Surgical
trans-sternal thymectomy
15746
Intervention_Pharmacological
pyridostigmine
15747
Intervention_Pharmacological
vecuronium
15748
Intervention_Pharmacological
pyridostigmine
15749
Intervention_Pharmacological
vecuronium
15750
Intervention_Pharmacological
vecuronium
15751
Intervention_Pharmacological
vecuronium
15752
Outcome_Physical
onset time
15753
Outcome_Physical
peak effect
15754
Outcome_Physical
relative resistance
15755
Outcome_Physical
delayed onset time
15756
Participant_Condition
patients with myasthenia gravis .