When Things Go Wrong
If a patient requires reversal of medication-induced respiratory depression, either naloxone or flumazenil may work. No good studies demonstrate which of these is the drug of choice. Obviously, if the patient has received only a narcotic, naloxone is indicated, whereas if a benzodiazepine alone was used, flumazenil should be given. If both a narcotic and benzodiazepine were used to sedate the patient, either drug would theoretically work. Because the analgesic effect of the narcotic may still be important, some suggest using flumazenil to reverse respiratory depression in these circumstances. Several studies show that flumazenil is safe and efficacious in reversing sedation in patients given a combination of a benzodiazepine and an opioid.63-65 However, flumazenil will sometimes restore consciousness without improving respiration.66,67 Patients who do not breathe adequately after flumazenil may require naloxone. Drugs such as propofol or methohexital cannot be reversed.
Another anxiety-provoking event during procedural sedation is laryngospasm. Frequently this response is transient and may require no interventions. If it persists for more than several seconds, laryngospasm may be reversed with bagging. On rare occasions, persistent severe laryngospasm may require nebulized lidocaine or very small doses of succinylcholine (0.1 mg/kg).68 One case report suggested that flumazenil can reverse midazolam-induced laryngospasm.69
Other adverse effects include vomiting either intraor post-procedure. Since aspiration is always a consideration, roll the patient on his or her side and suction as needed. As mentioned before, some children may have paradoxical reactions to benzodiazepines, which are sometimes responsive to flumazenil.