Disclaimer to the On-line Edition
This Manual has been designed for use in the NICU at London Health Sciences Centre (LHSC), London, Ontario, Canada, and represents clinical practice at this institution. The information contained within the Manual may not be applicable to other centres. If users of this Manual are not familiar with a drug, it is recommended that the official monograph be consulted before it is prescribed and administered. Any user of this information is advised that the contributors, Editor and LHSC are not responsible for any errors or omissions, and / or any consequences arising from the use of the information in this Manual.
Last Uploaded: Wednesday October 29, 2014
- to increase cardiac output
- a synthetic catecholamine which is similar in structure to dopamine
- not effective when given orally because of rapid first-pass effect
- pharmacological effects are due to direct interactions with both alpha and beta adrenergic receptors; does not appear to be involved in the release of norepinephrine nor does it act at dopaminergic receptors
- a racemic (ie. 2 enantiomeric forms) mixture is used clinically; the (-) isomer is an alpha1 receptor agonist, the (+) isomer is an alpha1 receptor antagonist; both isomers appear to have agonist activity at beta1 and beta2 receptors
- stimulation of alpha1 receptors results in constriction of systemic arterioles
- stimulation of beta2 receptors results in dilation of systemic arterioles
- stimulation of beta1 receptors results in increased rate, contractility and conduction velocity of the heart
- dobutamine has relatively more prominent inotropic (contraction) than chronotropic (rate) effects on the heart; this, however, has not been a consistent finding in clinical studies
- dobutamine is about 4 times as potent as dopamine in terms of contractile potency at comparable, low doses. At higher doses dobutamine decreases peripheral resistance (presumably because the beta2 vasodilator effect predominates over the alpha1 constrictor effect) in contrast to dopamine which increases peripheral resistance (due to alpha1 receptor stimulation)
blood pressure may remain unchanged or be only slightly elevated; heart rate is usually not substantially changed
|as the result of|
- a positive inotropic effect, and
- a decrease in peripheral resistance,
- significant increases in heart rate and blood pressure have been reported in some patients
- heart rate > 200 BPM and systolic BP > 90 mmHg should be avoided. The situation should be re-assessed and the dosage adjusted accordingly.
- less frequent adverse effects include vomiting and ectopic heart beats
- local: blanching, tissue ischemia or necrosis may occur with extravasation. Use phentolamine (see phentolamine monograph) if this occurs.
- the initial recommended dose for continuous infusion is 1-2 mcg/kg/min; this may be titrated to 7.5 to 10 mcg/kg/min given as a continuous infusion, up to a maximum of 20 mcg/kg/min
- dobutamine standard concentrations for NICU implemented Oct 1, 2014:
1 kg or less 1 mg/mL
over 1 kg 2 mg/mL
- Infusion standard concentration for weight to be ordered along with desired therapeutic dosing through HUGO, rate will be calculated electronically.
- 12.5 mg/mL, 10 mL vial
- Supplied by pharmacy as standard concentrations of 1mg/mL (supplied as 50mg/50mL of IV fluid ordered) and 2mg/mL (100mg/50mL of IV fluid ordered)
- Standard Concentration Reference Sheets can be found on the NICU Intranet here
- McEvoy G K (ed): AHFS Drug Information, American Society of Hospital Pharmacists, 1991.
- The Pharmacological Basis of Therapeutics, Gilman AG, Goodman LS Rall TW and Murad F (eds), 7th Edition, MacMillan, 1985
- Roberts, RJ: Drug Therapy in Infants, W.B. Saunders, Toronto, 1984.
- Taketomo CK, Hodding JH and Kraus DM: Pediatric Dosage Handbook, Lexi-Comp Inc., Cleveland, 1992.
- Personal Communication, Eli Lilly Canada Inc.