Metaraminol Tartrate

UNCONTROLLED WHEN PRINTED

Introduction

Metaraminol is a sympathomimetic, adrenoceptor stimulant.
It directly and indirectly stimulates the alpha receptors in the sympathetic nervous system.
Alpha stimulation causes vasoconstriction with an increase in both systolic and diastolic blood pressure and an increase in systemic vascular resistance.
It has a positive inotropic effect on the heart and a peripheral vasoconstrictor action
Onset: 1 to 2 minutes. Duration up to 20 minutes. Half-life only minutes.

Indications

Adjunctive treatment of hypotension after adequate fluid resuscitation due to:

Contraindications

Precautions / Notes

Use of Metaraminol with (MAOI’s) or tricyclic antidepressants may result in potentiation of the pressor effect.
Hypotension can be defines as less than 30% of the patients base line SBP or in children (70mmHg +(2xage)) in the 1- 10yo.
Asthma – risk of allergy to sulphides
Digitalised patients – risk of arrythmias

Management

Critical Care Paramedic only

Adult:

IV/IO:
- IV/IO 0.5mg - 1mg, repeat >3 min
- Dilute 10mg/1ml into 20ml NaCl 0.9% to provide a solution of 0.5mg/ml.
Infusion:
- 20mg in 50ml in NaCl 0.9% at 0.5 to 5 ml/hr (0.4mg/ml) titrate to BP/haemodynamic status

Paediatric:

IV/IO:
- 0.01mg/kg, repeat >3 min
- Dilute 5mg/0.5ml into 50ml normal saline to provide solution of 0.1mg/ml
Infusion:
- 0.15mg/kg in 50ml in normal saline at 1 to 10 ml/hr (0.05-0.5mcg/kg/min)
- Titrate to BP / haemodynamic status.

Special Considerations

Administer dose cautiously as rapidly induced hypertensive response may cause:

Causes tissue necrosis, avoid extravasation.

References

Presentation

10 mg/mL ampoule

Colour assist:

Directorate

Clinical Services

Responsible Manager

Head of Clinical Services

Date of Issue

Date of Expiry