Commonly used drugs in bronchoscopy
| Drug | Dose | Speed of Onset / Duration of Action / Half-life | Common / Serious Side Effects | Comments |
|---|---|---|---|---|
| Midazolam | Slow IV injection - maximum rate 2 mg/min ▸ Initial dose: 2 mg-2.5 mg (0.5-1 mg in the frail or elderly) given 5-10 mins before procedure ▸ Supplemental doses, if required: 1 mg (0.5-1 mg in frail or elderly), at 2-10 mins intervals ▸ Usual maximum total dose: 3.5-7 mg (3.5 mg in frail or elderly) for standard bronchoscopic procedures. May be higher in longer procedures (e.g. EBUS) | Onset of Sedation ▸ Within 2 mins, with maximum effect at 5-10 mins. (May be longer in frail or elderly or those with chronic illnesses) Duration of Action ▸ Variable, but typical range is 30-120 mins Approximate half-life ▸ 1.5-2.5 hours | Respiratory depression, apnoea, bronchospasm, laryngospasm, hypotension, heart rate alterations, cardiac arrest. Life-threatening side effects and prolonged sedation are more likely in the elderly and those with impaired respiratory or cardiovascular status, hepatic impairment, renal impairment, myasthenia gravis, and with rapid IV injection. | Enhanced sedation and increased risk of respiratory depression when combined with opioids. When combined sedation is used, opioids should always be administered prior to midazolam. To prevent risk of accidental overdose, only 1 mg/mL vials should be available in bronchoscopy suites. 2 mg/mL or 5 mg/mL vials should not be available unless a formal risk assessment has been undertaken. |
| Fentanyl | Slow IV injection - usually over 1-3 mins ▸ Initial dose: 25 micrograms ▸ Supplemental doses, if required: 25 micrograms ▸ Usual maximum total dose: 50 micrograms | Onset of Sedation ▸ Almost immediate, with maximum effect at 5 mins Duration of Action ▸ Variable, but typical range is 30-60 mins Approximate half-life ▸ 2-7 hours | Nausea, vomiting and other GI upset, myoclonic movements, respiratory depression, apnoea, bronchospasm, laryngospasm, hypo/hypertension, arrhythmia, cardiac arrest. Caution in elderly patients and those with impaired respiratory or cardiovascular status, hepatic impairment and myasthenia gravis. | Enhanced sedation and respiratory depression when given with benzodiazepines. When combined sedation is used, opioids should always be administered prior to midazolam. |
| Alfentanil | Slow IV injection - usually over 30 secs ▸ Initial dose: 250 micrograms ▸ Supplemental doses, if required: 250 micrograms ▸ Usual maximum total dose: 500 micrograms | Onset of Sedation ▸ Almost immediate onset and maximum effect Duration of Action ▸ Variable, but usually shorter than fentanyl Approximate half-life ▸ 1-2 hours | See Fentanyl | See Fentanyl |
| Lidocaine | Intranasal ▸ Lidocaine 2% gel: 6 mL (120 mg) Oropharnyx ▸ Lidocaine 10% spray: 3 actuations (30 mg) Vocal cords, tracheobronchial tree ▸ Lidocaine 1% solution: 2 mL boluses applied topically, as required Maximum total dose (see Table 3) ▸ Use minimum dose to achieve effective cough suppression and patient comfort. Subjective symptoms of Lidocaine toxicity are common when >9.6 mg/kg is used; much lower doses are usually sufficient. | Onset of Action ▸ 3 to 5 mins Duration of Action ▸ Variable, but typical range is 60-90 mins Approximate half-life ▸ 1.5-2 hours | CNS effects (confusion, blurred vision, dizziness, drowsiness, lightheadedness, myoclonus, nausea, nystagmus, paraesthesia, restlessness, tremulousness, coma, convulsions, respiratory failure) CVS effects (hypotension, bradycardia, arrhythmia, cardiac arrest). Methaemoglobinaemia (rare). Caution in those with hepatic and cardiac dysfunction, and with significant renal impairment. | |
| Adrenaline | Topical ▸ Adrenaline 1:10,000: 2 to 10 mL | Hypertension, tachycardia, arrhythmia, tremor. |
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.