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.

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.

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 NHS Highland Extravasation Protocol on intranet. 

SIDE-EFFECTS:

• Tachycardia and arrhythmias.
• Angina.

MONITORING:

• Continuous ECG and blood pressure monitoring.
• Renal function and urine output/fluid balance.