4.1 Therapeutic indications
Noradrenaline ((CAPITAL 'N' DELETED)(norepinephrine) 1:1000 is recommended for use as an emergency measure in the restoration of blood pressure in cases of acute hypotension.
4.2 Posology and method of administration
Route of Administration:
For intravenous use.
Route and method of infusion:
Noradrenaline (((CAPITAL 'N' DELETED)(norepinephrine) 1:1000 should be administered in a diluted solution via a central venous catheter.
The infusion should be at a controlled rate using either a syringe pump or an infusion pump or a
drip counter.
Dilution instructions:
Noradrenaline (((CAPITAL 'N' DELETED)(norepinephrine) 1:1000 should be diluted either with dextrose 5%, or with isotonic dextrose saline.
Adults:
Either add 2 ml of noradrenaline ((CAPITAL 'N' DELETED)(norepinephrine) 1:1000 to 48 ml 5% dextrose for administration by syringe pump, or add 20 ml of noradrenaline (norepinephrine) 1:1000 to 480 ml 5% dextrose for administration by drip counter.
In both cases the final concentration of the infusion solution is 80 mg/litre noradrenaline (NOREPINEPHRINE DELETED) tartrate, which is equivalent to 40 mg/litre noradrenaline (NOREPINEPHRINE DELETED) base. If other dilutions are used check the calculation carefully before starting treatment.
Initial rate of infusion:
The initial rate of infusion should be between 10 ml/hour and 20 ml/hour (0.16 ml/min to 0.33 ml/min). This is equivalent to 0.8 mg/hr to 1.6 mg/hr noradrenaline (NOREPINEPHRINE DELETED) tartrate (or 0.4 mg/hr to 0.8 mg/hr noradrenaline (NOREPINEPHRINE DELETED) base).
Titration of dose:
Once an infusion of noradrenaline (NOREPINEPHRINE DELETED) has been established the dose should be titrated according to the pressor effect observed. There is great individual variation in the dose required to attain and maintain normotension. The aim should be to establish a low normal systolic blood pressure (100-120 mm Hg) or to achieve an adequate mean arterial blood pressure (greater than 80 mm Hg).
Duration of Treatment and Monitoring:
Noradrenaline ((CAPITAL 'N' DELETED)(norepinephrine) 1:1000 should be continued for as long as vasoactive drug support is indicated. The patient should be monitored carefully for the duration of noradrenaline (norepinephrine) 1:1000 therapy.
4.3 Contraindications
The use of pressor amines during cyclopropane or halothane anaesthesia may cause serious cardiac arrhythmias. Because of the possibility of increasing the risk of ventricular fibrillation, noradrenaline ((CAPITAL 'N' DELETED)(norepinephrine) 1:1000 should be used with caution in patients receiving these or any other cardiac sensitising agent or who exhibit profound hypoxia or hypercarbia.
Particular caution should be observed in patients with coronary, mesenteric or peripheral vascular thrombosis because noradrenaline (norepinephrine) 1:1000 may increase the ischemia and extend the area of infarction. Similar caution should be observed in patients with hypotension following myocardial infarction and in patients with Prinzmetal’s variant angina.
4.4 Special warnings and precautions for use
Noradrenaline (CAPITAL 'N' DELETED)(norepinephrine) 1:1000 should be used only in conjunction with appropriate blood volume replacement. When infusing noradrenaline (norepinephrine) 1:1000, the blood pressure and rate of flow should be checked frequently to avoid hypertension. Extravasation of the solution may cause local tissue necrosis. The infusion site should be checked frequently. If extravasation occurs, the area should be infiltrated with phentolamine without delay.
It has been suggested that phentolamine may be added directly to the infusion flask to act as an antidote against sloughing without affecting the vasopressor activity of noradrenaline (norepinephrine) 1:1000.
4.5 Interaction with other medicinal products and other forms of interaction
Noradrenaline ((CAPITAL 'N' DELETED)norepinephrine) 1:1000 should be used with extreme caution in patients receiving monoamine oxidase inhibitors or tricyclic antidepressants because severe, prolonged hypertension may result. The elderly may be especially sensitive to the effects of Noradrenaline ((CAPITAL 'N' DELETED)norepinephrine) 1:1000.
4.6 Pregnancy and lactation
Noradrenaline (CAPITAL 'N' DELETED)norepinephrine) 1:1000 may impair placental perfusion and induce foetal bradycardia. It may also exert a contractile effect on the pregnant uterus and lead to foetal asphyxia in late pregnancy. These possible risks to the foetus should therefore be weighed against the potential benefit to the mother.
6.2 Incompatibilities
NORPINEPHRINE DELETED
Infusion solutions containing noradrenaline tartrate have been reported to be incompatible with the following substances: alkalis and oxidising agents, barbiturates, chlorpheniramine, chlorothiazide, nitrofurantoin, novobiocin, phenytoin, sodium bicarbonate, sodium iodide, streptomycin.
