TAM (Treatments and Medicines) NHS Highland
For use in Critical Care Areas for adults only. Administer via a large peripheral vein or central line (*caution: different strengths*).
MECHANISM OF ACTION:
- Stimulates beta-1 and beta-2 adrenoceptors producing an increase in cardiac output by increasing heart rate and myocardial contractility.
- Half-life = 2.5 to 5 minutes.
USES:
- For bradycardia in patients with adverse signs (systemic hypotension, signs of cerebral hypoperfusion, progressive heart failure, angina, or life-threatening ventricular arrhythmias) and/or risk of asystole which has not responded to atropine, until temporary or permanent pacing can be initiated.
CONTRA-INDICATIONS:
- Recent MI: may increase myocardial oxygen demand.
- Do not give at the same time as adrenaline.
- Ventricular arrhythmias or tachyarrhythmias.
- Heart block due to digoxin toxicity.
- Angina: may exacerbate.
CAUTIONS:
- Phaeochromocytoma.
- Hypotension due to uncorrected hypovolaemia.
- Hyperthyroidism.
PRESENTATION:
- Isoprenaline hydrochloride 1mg in 5mL ampoules.
- Stored in refrigerator.
ADMINISTRATION:
For PERIPHERAL administration (4 micrograms per mL):
- Add 2mg (10mL) to 500mL glucose 5% (withdraw 10mL from bag before adding Isoprenaline) to prepare a 4 microgram per mL solution.
- Glucose 5% is the preferred diluent but sodium chloride 0.9% may be used if there are concerns around hyperglycaemia.
- Administer via a volumetric pump via a large peripheral vein.
For CENTRAL administration (40 micrograms per mL)
- Dilute 2mg (10mL) to 50mL with glucose 5% to prepare a 40 microgram per mL solution.
- Administer via syringe pump.
| Isoprenaline | Peripheral Administration (volumetric infusion) |
Central Administration (syringe pump) |
| Prescribe | 2mg in 500mL | 2mg in 50mL |
| Drug dose to be added | 2mg in 10mL (2 ampoules) | 2mg in 10L (2 ampoules) |
| Diluent to be added |
490mL glucose 5% (withdraw 10mL from 500mL bag glucose 5% before adding isoprenaline) *sodium chloride 0.9% may be used if concerns around hyperglycaemia* |
40mL glucose 5% |
| Final volume | 500mL | 50mL |
| Final concentration | 4micrograms/mL | 40micrograms/mL |
DOSE AND RATE:
- Usual dose is 1 to 5 micrograms/minute.
- Commence at 1 microgram/minute and titrate upwards at intervals of 2 to 3 minutes until an adequate heart rate is achieved (50 to 60 beats per minute or target set by medical team). Discuss with medical staff before increasing rate further if side-effects such as hypotension or arrhythmias occur.
| Dose (micrograms/minute) | Rate (mL/hour) 4 micrograms/mL solution PERIPHERAL administration |
Rate (mL/hour) 40 micrograms/mL solution CENTRAL administration |
| 1 | 15 | 1.5 |
| 2 | 30 | 3.0 |
| 3 | 45 | 4.5 |
| 4 | 60 | 6.0 |
| 5 | 75 | 7.5 |
STABILITY:
- 24 hours.
- Do not allow the syringe or infusion to run out. A syringe or infusion can be made up to a maximum of one hour in advance and labelled clearly with contents and expiry. Refer to local nursing guidelines for switching over infusions or syringes.
EXTRAVASATION:
- The infusion has a low pH and extravasation is likely to cause venous irritation and tissue damage. If given peripherally, use a large vein with monitoring for phlebitis. Resite catheter at first signs of inflammation.
- Please refer to Peripheral extravasation injury (Non-cancer).
SIDE-EFFECTS:
- Tachycardia and arrhythmias.
- Angina.
MONITORING:
- Continuous ECG and blood pressure monitoring.
- Renal function and urine output/fluid balance.