Alfenta+bentley+notes

From Dr: Bentley's slides and note set on opioids:


 * Alfentanil**:


 * Developed/synthesized in the late 1970s
 * 1/3 less potency & duration of fentanyl
 * Less lipid soluble than fentanyl
 * Highly protein bound to alpha 1-acid glycoprotein
 * Undergoes hepatic metabolism
 * via N-dealkylation
 * efficient @ 96% in 60 minutes
 * unpredictable infusion relation to CYP450-3A4 variability in activity in individuals
 * erythromycin may prolong
 * Increased N/V
 * Rapid effect-site equilibration=1.4 minutes
 * because of low pKa, 90% is unionized so crosses BBB
 * Useful to blund SNS stimuli
 * Smaller Vd
 * highly protein bound