Antagonists available for sedative drugs used in bronchoscopy
| Drug | Dose | Speed of Onset / Duration of Action / Half-life | Common / Serious Side Effects | Comments |
|---|---|---|---|---|
| Flumazenil | To reverse midazolam ▸ Initial dose: 200 micrograms IV over 15 secs ▸ Supplemental doses: 100 micrograms every 60 secs if inadequate response ▸ Typical cumulative dose range: 300-600 micrograms ▸ Maximum total dose: 1 mg | Onset of Action ▸ 1 min Duration of Action ▸ 1-4 hours Approximate half-life ▸ 40-80 mins | Nausea, vomiting, anxiety, agitation, dizziness, hypertension, tachycardia. May lower seizure threshold. May cause withdrawal in chronic benzodiazepine users. | Flumazenil has a shorter duration of action than midazolam, and so patients should be observed long enough to ensure that sedation and cardiorespiratory depression does not recur once the effect of flumazenil ceases. Further doses may be required. Where combined sedation with midazolam and opioid has been used, it is recommended that flumazenil is administered first, unless a large dose of opioid has been given |
| Naloxone | To reverse opioids ▸ Initial dose: 100-200 micrograms IV ▸ Supplemental dose: 100 micrograms every 2 mins if inadequate response | Onset of Action ▸ 2-3 mins Duration of Action ▸ 45 mins to 4 hours Approximate half-life ▸ 1-1.5 hours | Nausea, vomiting, dizziness, headache, tachycardia, hypo/hypertension. May cause withdrawal in chronic opioid users. | Naloxone has a shorter duration of action than many opioids, and so patients should be observed long enough to ensure that sedation and cardiorespiratory depression does not recur once its effect ceases. Further doses may be required. |
Adapted from 'Drugs in Bronchoscopy' (BTS Bronchoscopy eLearning Module available at: http://learninghub.brit-thoracic.org.uk/?bts=topic¶m=3), with kind permission of Toby Capstick and Daniel G Peckham.