Dopamine Hydrochloride for newborn intensive care
To improve cardiac output, blood pressure and urine output in critically ill infants with hypotension.
Dose and administration
2-20 micrograms/kg/minute by continuous IV infusion¹.
Begin at a low dose and titrate by monitoring clinical response.
Maximum recommended dose 20 micrograms/kg/minute².
If doses greater than 10 - 15 micrograms/kg/min are required then dobutamine or noradrenaline may be added¹.
Administer via a central line (UVC, Longline, or Surgical CVL). If no central access available, use a large vein.
Usual dilution 30 mg/kg (0.75 ml/kg) dopamine to make 50 ml with Normal Saline or D5W
1 ml/hour = 10 micrograms/kg/minute.
Dopamine (mg) in 50ml IV solution = 3 x weight (kg) x dose (micrograms/kg/min)
IV Rate (ml/hr)
Indications
To improve cardiac output, blood pressure and urine output in critically ill infants with hypotension.
Contraindications
Hypersensitivity to sympathomimetic amines and sulfites.
Uncorrected tachyarrhythmias.
Precautions
Hypovolaemia- correct before commencing dopamine
Hyperthyroidism
Caution if administration concurrent with phenytoin.
Clinical pharmacology
Dopamine is a sympathomimetic catecholamine which exhibits alpha adrenergic, beta adrenergic, and dopaminergic agonism. The mechanism of action in neonates is controversial. Relative effects of dopamine at different doses are uncertain because of developmental differences in:
endogenous noradrenaline stores
alpha and beta adrenergic, and dopaminergic receptor functions
the ability of the neonatal heart to increase stroke volume. Responses tend to be individualised.
Dopamine is metabolised very rapidly and is effective only when administered intravenously by continuous infusion. The half-life of dopamine effect is 2 minutes, which is the same as the other catecholamines. No information available on protein binding. 97% is excreted in the urine as metabolites.
Drug effects are dose dependent:
Low dose: 2-5 micrograms/kg/minute. Little effect seen on heart rate or cardiac output. Increased blood flow accompanied by increased urine output.
Intermediate doses: 5-15 micrograms/kg/minute. An increase in cardiac contractility and cardiac output results in increased normal blood flow and heart rate.
High dose: 15 micrograms/kg/minute. Alpha adrenergic effects begin to dominate: increased systemic and pulmonary vascular resistance,a decrease in blood flow, and a reduction in cardiac output in the neonate especially in the first few days of life³. Decrease in normal perfusion.
Possible adverse effects
Venous irritation, soft tissue injury at the site of IV injection.
Vomiting, tachycardia, vasoconstriction, hypotension.
Infusions > 20 micrograms/kg/minute are associated with an increased risk of dysrhythmias eg. tachycardia and, bradycardia, and vasoconstriction¹
Less common: bradycardia, hypertension.
Special considerations
Dosage range is determined by type of desired clinical effect. Start at the lower end of the desired range and titrate according to clinical response.
Volume loading is considered before commencing dopamine infusion.
Use with caution in patients with persistent pulmonary hypertension of the newborn.
Suggested treatment for tissue sloughing following IV infiltration: inject a 1 mg/ml solution of phentolamine into the affected area. The usual amount needed is 1-5 ml, depending on the size of the infiltrate.
Dopamine effects are prolonged and intensified by beta blockers.
General anaesthetic: increased risk of arrhythmias or hypertension.
Phenytoin may lower blood pressure.
Acidosis decreases effectiveness of dopamine.
Administration via the UAC is not recommended¹
Management of Dopamine Administration
Description
Clear, colourless solution 40 mg/ml in 5 ml ampoules.
pH 2.5-4.5 (contains 1% sodium metabisulfite)
Prescription
Charted on fluid chart giving:
rate in ml/hour
dose in micrograms/kg/minute
Also charted on drug chart under continuous infusions giving:
amount of drug to be added
base fluid type and volume
rate in mL/hour and dose in micrograms/kg/minute
Administration
Continuous Infusion
Should be administered via a central line (UVC, Longline, or Surgical CVL). If no central access available, use a cannula in a large vein.
Administered by a nurse with Neonatal IV Drug Certification.
Discoloration of solution (yellow, brown, pink, purple) indicates decomposition and should be discarded.
Dilute 30 mg/kg (0.75 ml/kg) dopamine to make 50ml with NS or D5W - 1 ml/hour = 10 micrograms/kg/minute.
Compatible with sodium chloride 0.9%, glucose 5% and glucose 10%
Compatible at Y injection site with dobutamine, morphine, heparin, PGE1.
Incompatible with acyclovir, indomethacin, insulin, frusemide,, sodium bicarbonate and other alkaline solutions including phenytoin. No information available on IVN, therefore avoid co-infusion if possible.
Do NOT mix with any other drug, blood, or blood products. Do NOT flush line.
Administer via a syringe pump.
Change fluid and tubing every 48 hours or earlier if solution is discoloured.
Nursing considerations
Monitor for adverse reactions.
Observe closely for IV filtration; discontinue immediately and notify doctor/NS-ANP. Avoid extravasation of drug as may cause necrosis and tissue sloughing.
Assess colour and temperature of extremities.
Continuous blood pressure monitoring. If a disproportionate rise in diastolic pressure (decreased pulse pressure) notify doctor/NS-ANP immediately.
Continuous cardiorespiratory monitoring.
Document vital signs hourly and PRN.
Monitor urinary output.
Storage
At room temperature <30°C. Protect from light.
Diluted solution stable for 48 hours at room temperature.