Methohexital is an ultra-sho-acting barbiturate that provides sedation and amnesia for sho, invasive procedures. Barbiturate administration may precipitate bronchospasm in patients with moderate to severe reactive airway disease, thus limiting its use in those patients. There is some evidence that ketamine may have a mild, transient bronchodilatory effect. Midazolam, etomidate, and propofol have no clinically significant effect on bronchial smooth muscle tone. Of the listed agents, only ketamine provides analgesia in addition to sedation.