Dobutamine hydrochloride

dr.joan

Dobutamine hydrochloride:
Trade name: Dobutrex

Drug classes:

· Sympathomimetic
· β1-selective adrenergic agonist
Pregnancy: (Category

Therapeutic actions:

Positive inotropic effects are mediated by β1- adrenergic receptors in the heart; increases the force of myocardial contraction with relatively minor effects on heart rate, arrhythmogenesis; has minor effects on blood vessels.

Indications

· For inotropic support in the short-term treatment of adults with cardiac decompensation due to depressed contractility, resulting from either organic heart disease or from cardiac surgical procedures
· Investigational use in children with congenital heart disease undergoing diagnostic cardiac catheterization, to augment CV function

Dosage

§ Available Forms: Injection 12.5 mg/mL.
§ Administer only by IV infusion.
§ Titrate on the basis of the patient's homodynamic/renal response.
§ Close monitoring is necessary.

Adult:

2.5---15 µg/kg/min IV is usual rate to increase cardiac output; rarely, rates up to 40 µg/kg per minute are needed.

IV facts

• Preparation: Reconstitute by adding 10 mL Sterile Water for Injection or 5% Dextrose Injection to 250-mg vial. If material is not completely dissolved, add 10 mL of diluent. Further dilute to at least 50 mL with 5% Dextrose Injection, 0.9% Sodium Chloride Injection, or Sodium Lactate Injection. Store reconstituted solution under refrigeration for 48 h or at room temperature for 6 h. Store final diluted solution in glass or via flex container at room temperature. Stable for 24 h. Do not freeze. (Note: drug solutions may exhibit a color that increases with time; this indicates oxidation of the drug, not a loss of potency.)
• Infusion: May be administered through common IV tubing with dopamine, lidocaine, tobramycin, nitroprusside, potassium chloride, or protamine sulfate. Titrate rate based on patient response--P, BP, rhythm; use of an infusion pump is suggested.
• Incompatibilities: Do not mix drug with alkaline solutions, such as 5% Sodium Bicarbonate Injection; do not mix with hydrocortisone sodium succinate, cefazolin, cefamandole, neutral cephalothin, penicillin, sodium ethacrynate; sodium heparin.
• Y-site Incompatibilities: Do not mix with acyclovir, alteplase, aminophylline, foscarnet.

Adverse effects

• CNS: Headache
• GI: Nausea
• CV: Increase in heart rate, increase in systolic blood pressure, increase in ventricular ectopic beats (PVCs), anginal pain, palpitations, shortness of breath

Clinically important interactions

• Drug-drug

v Increased effects with TCAs (eg, imipramine), furazolidone, methyldopa
v Risk of severe hypertension with β-blockers
v Decreased effects of guanethidine with dobutamine

Nursing Considerations

v Arrange to digitalize patients who have atrial fibrillation with a rapid ventricular rate before giving dobutamine--dobutamine facilitates AV conduction.
v Monitor urine flow, cardiac output, pulmonary wedge pressure, ECG, and BP closely during infusion; adjust dose/rate accordingly.