A. Benzodiazepines
Benzodiazepines have anxiolytic and amnestic properties. They
do not have analgesic effects. Benzodiazepines act by augmenting
GABA (gamma amino butyric acid) transmission, which is an inhibitory
neurotransmitter in the brain. Clinical effects include decreased cerebral
metabolism and blood flow, sedation, hypnosis, anxiolysis,
anticonvulsant activity, anterograde amnesia, muscle relaxation, dose
dependent depression of breathing, and decreased tidal volume. Use of
benzodiazepines without opioid in presence of painful stimulus can
cause hyperalgesia and agitation [13].- Midazolam [2,13]^
water soluble, short acting, rapidly crosses BBB
Dosing:
o Loading dose: 0.2mg/kg
o continuous infusion 0.4mg/kg/minute
o invasive procedures: 0.05-0.2mg/kg bolus dose
o long term sedation with intubation: 0.025-0.05mg/kg/hour
Onset & elimination: 30 minutes. Half life 6 hours
Side effects: respiratory depression and hypotension, tolerance.
Precautions: Withdrawal symptoms after prolonged IV use, which
include agitation, poor visual tracking, constant choreoathetoid