Acute hypotension despite fluid therapy in shock (in children, preferably use epinephrine for this indication)
Forms and strengths, route of administration
8 mg of norepinephrine tartrate in 4 ml ampoule (2 mg/ml), equivalent to 4 mg of norepinephrine base in 4 ml (1 mg/ml),for IV infusion
Dosage
The doses are expressed as norepinephrine tartrate and intended for peripheral IV administration only.
Use diluted solution in 0.9% sodium chloride (NaCl 0.9%) or 5% glucose (G5%) or Ringer lactate (RL):
Child under 40 kg: add 1 ml (2 mg of NEP tartrate) to 39 ml of NaCl 0.9%, G5% or RL to obtaina 0.05 mg/ml (50 micrograms/ml) solution
Child 40 kg and over and adult: add 2 ml (4 mg of NEP tartrate) to 38 ml of NaCl 0.9%, G5% or RL to obtain a 0.1 mg/ml (100 micrograms/ml) solution
Administer by continuous IV infusion usingan infusion or syringe pump:
Child and adult: 0.1 microgram/kg/min, increaseif necessary by 0.05 micrograms/kg/min every 10 minutes for the first hour, then every hour (max. 1 microgram/kg/min)
Once desired response is achieved, discontinue gradually, in decrements of 0.05 micrograms/kg/min every hour. Do not discontinue abruptly.
The infusion rate is calculated as follows:[desired dose (microgram/kg/min) x weight (kg) x 60 min] ÷ concentration (microgram/ml).
Example, for a child 20 kg, dose 0.1 microgram/kg/min, solution concentration 50 micrograms/ml:
NEP dose (microgram/kg/min)
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Infusion rate(ml/hour)
2.4
3.6
4.8
6
7.2
8.4
9.6
10.8
12
Contra-indications, adverse effects, precautions
Administer with caution to patients with hypertension, hypotension due to volume depletion (except as an emergency measure), thrombosis, hyperthyroidism and to older patients.
May cause: arrhythmia, hypertension, agitation, headache; tissue necrosis following extravasation (use a large vein for IV administration).
Pregnancy and breast-feeding: no contra-indication
Remarks
Norepinephrine is colourless: discard any ampoules with a pink or brownish colour.