Sedatives typically have more than one of these actions, although one may predominate.
This determines the equipment that one should have readily available prior to starting the procedure.
It is insoluble in water and is commercially prepared in propylene glycol. The onset of action is relatively rapid, but the duration of action is 2-4 hours.
It is metabolized almost exclusively in the liver; therefore, this drug should not be used in patients with cirrhosis.
Benzodiazepines differ by the methods they can be given, time of onset, action duration, mechanism of metabolism, and presence of active metabolites.
As mentioned earlier, their mechanism of action is seen clinically as anxiolysis, amnesia, and sedation; if a particular procedure is painful, these drugs must be given with analgesic agents.
Cardiovascular depression, resulting in hypotension with reflex tachycardia, is another adverse effect, but it is not significant at typical doses unless hypovolemia is present or unless it is coadministered with centrally acting analgesics.
Be cautious when giving a hepatically metabolized benzodiazepine (eg, midazolam) to a patient with cirrhosis.Stimulation of this receptor potentiates the inhibitory effects of gamma-aminobutyric acid (GABA) on GABA-A receptors.This results in chloride influx, hyperpolarization, and decreased ability of the neuron to reach an action potential, producing sedation and anxiolysis.When drugs are used as adjuncts, decreasing the dose of each respective drug is important, so as to decrease the incidence of adverse effects.The medications below are presented according to pharmacologic class.Nonetheless, clinicians may underuse sedation, usually from a lack of experience or from unchallenged myths regarding its use.