Dopamine

Dopamine – drug with vasopressor, cardiotonic action.

Form of release and structure

Dopamine is produced in the form of a concentrate for preparation of solution for infusions (in ampoules on 5 ml, on 5, 10, 250 or 500 ampoules in a cardboard pack or a box).

Is a part of 1 ml of drug:

• Active agent: a dopamine hydrochloride – 5, 10, 20, 40 mg;
• Auxiliary components: disodium sulfite, Acidum hydrochloricum 0,1M (to pH 3,5-5,0), water for injections.

Indications to use

• Shock of various genesis (cardiogenic shock; after recovery of volume of the circulating blood – hypovolemic, postoperative, acute and infectious and toxic anaphylaxis);
• Syndrome of "low cordial emission" at cardiac patients;
• Acute cardiovascular insufficiency;
• Arterial hypotension.

Contraindications

• Thyrotoxicosis;
• Tachyarrhythmia;
• Pheochromocytoma;
• Fibrillation of ventricles;
• Simultaneous use with monoamine oxidase inhibitors, galogensoderzhashchy anesthetics and cyclopropane;
• Hypersensitivity to drug components.

Dopamine should be applied with care to the feeding and pregnant women, children to 18 years, and also the patient with a hypovolemia expressed by a stenosis of the mouth of an aorta, a myocardial infarction, disturbances of a heart rhythm (ventricular arrhythmias, fibrillations of auricles), a metabolic acidosis, a hypercapnia, a hypoxia, hypertensia in a "small" circle of blood circulation, occlusal diseases of vessels (including a thrombembolia, atherosclerosis, the diabetic endarteritis obliterating a thromboangitis, an obliterating endarteritis, freezing injury, a Raynaud's disease), a diabetes mellitus, bronchial asthma (if in the anamnesis hypersensitivity to disulphite was noted).

Route of administration and dosage

Dopamine is entered intravenously kapelno.

The dose of drug is established individually, depending on the size of arterial pressure, severity of shock and reaction of the patient to therapy:

• Area of low doses: with a speed of 0,1-0,25 mg a minute (0,0015-0,0035 mg/kg a minute) – for receiving an inotropic effect (increase in sokratitelny activity of a myocardium) and strengthening of a diuresis;
• Area of average doses: 0,3-0,7 mg a minute (0,004-0,01 mg/kg a minute) – at intensive surgical care;
• Area of the maximum doses: 0,75-1,5 mg a minute (0,0105-0,021 mg/kg a minute) – at septic shock.

For impact on arterial pressure increase in a dose up to 0,5 mg a minute and more is recommended, or at a constant dose of a dopamine in addition appoint noradrenaline (Norepinephrinum) in a dose of 0,005 mg a minute at the body weight of the patient about 70 kg.

Irrespective of the applied doses at development of disturbances of a cordial rhythm further increase in a dose is contraindicated.

To children the drug is administered in a dose 0,004-0,006 (as much as possible – 0,01) mg/kg a minute. Children, unlike adults, need to increase a dose gradually, i.e. since the minimum dose.

Dopamine rate of administering for achievement of optimum reaction of the patient needs to be selected individually. In most cases it is possible to maintain satisfactory condition of the patient at use of doses less than 0,02 mg/kg a minute.

Duration of injections is defined by specific features of the patient. There is a positive experience of therapy lasting up to 28 days. Drug withdrawal after stabilization of a clinical situation should be carried out gradually.

For cultivation of drug it is possible to use 5% dextrose solution in Ringer's solution of a lactate, Ringer's solution of a lactate and sodium of a lactate, 0,9% solution of sodium of chloride, 5% dextrose solution (including their mixes). For preparation of solution for intravenous infusion of 400-800 mg of a dopamine it is necessary to add to 250 ml of solvent (for achievement of concentration of a dopamine of 1,6-3,2 mg/ml). Infusion solution needs to be prepared just before use (stability of solution remains for 24 hours, except mixes with Ringer-laktata solution – at most 6 hours). Solution of Dopamine has to be colourless and transparent.

Side effects

During therapy development of disturbances from some systems of an organism which are shown as is possible:

• Cardiovascular system: more often – bradycardia or tachycardia, stenocardia, heartbeat, pains behind a breast, increase in end diastolic pressure in a left ventricle, conductivity disturbances, decrease or increase in arterial pressure, a vasospasm, expansion of the QRS complex (the first phase of a ventricular complex reflecting process of depolarization of ventricles); at use in high doses – supraventricular or ventricular arrhythmias;
• Central nervous system: more often – a headache; less often – motive concern, uneasiness, a mydriasis;
• Alimentary system: more often – vomiting, nausea;
• Allergic reactions: patients with bronchial asthma have a shock, a bronchospasm;
• Local reactions: at hit of Dopamine under skin – necroses of hypodermic cellulose and skin;
• Others: less often – an azotemia, an asthma, a piloerektion; seldom – a polyuria (at introduction in low doses).

Special instructions

Before administration of Dopamine by the patient who is in state of shock the hypovolemia needs to be skorregirovat introduction of a blood plasma and other blood-substituting liquids.

Infusion should be carried out under control of arterial pressure, heart rate, a diuresis, minute volume of blood, an ECG. At reduction of a diuresis without the accompanying lowering of arterial pressure it is necessary to reduce the Dopamine dose.

Monoamine oxidase inhibitors can cause arrhythmia, headaches, vomiting and other displays of hypertensive crisis therefore the patient receiving monoamine oxidase inhibitors within the last 2-3 weeks, Dopamine is appointed in initial doses, it is no more than 10% of components of a usual dose.

18 years are younger than strictly controlled researches of use of Dopamine for patients it was not carried out (there are separate messages on development in this group of sick arrhythmias and gangrene which is connected with its ekstravazation (distribution of drug to skin and hypodermic cellulose as a result of injury of a vein) at intravenous administration). For decrease in risk of emergence of an ekstravazation Dopamine, whenever possible, is recommended to be entered into large veins. To prevent a necrosis of fabrics at ekstravazalny hit of drug it is necessary to carry out immediately infiltration of 0,9% by chloride sodium solution in a dose of 10-15 ml from 5-10 mg of phentolamine.

Purpose of Dopamine at occlusal diseases of peripheral vessels and/or the IDCS (dessiminirovanny intravascular coagulation) in the anamnesis can lead to the sharp and expressed vasoconstriction, further – to a necrosis of skin and gangrene (it is necessary to carry out careful control, and at identification of symptoms of peripheral ischemia administration of Dopamine needs to be stopped immediately).

Medicinal interaction

At simultaneous use of Dopamine with some medicines there can be undesirable effects:

• Adrenostimulyatora, monoamine oxidase inhibitors (including furasolidone, Procarbazinum, селегилин), гуанетидин (increase in duration and strengthening of the cardiostimulating and pressor effects): strengthening of sympathomimetic effect;
• Diuretics: strengthening of diuretic effect;
• Inhalation medicines for the general anesthesia, derivatives of hydrocarbons (изофлуран, chloroform, cyclopropane, a halothane, энфлуран, метоксифлуран), tricyclic antidepressants, including Maprotilinum, cocaine, other sympathomimetics: strengthening of cardiotoxic effect;
• Beta adrenoblockers (propranolol) and phenyl propyl ketones: easing of effect of Dopamine;
• Guanetidin, guanadret, Methyldopum, мекамиламин, Rauwolfia alkaloids (the last prolong effect of a dopamine): easing of their hypotensive effect;
• Levodopa: increase in probability of development of arrhythmias;
• Hormones of a thyroid gland: perhaps mutual strengthening of their action;
• Ergotamine, ergometrine, oxytocin, methylergometrine: increase in vasopressor effect and risk of a gangrenosis, ischemia and heavy arterial hypertension, up to intracraneal hemorrhage.

Dopamine lowers anti-anginal effect of nitrates which, in turn, can reduce pressor effect of sympathomimetics and increase risk of development of arterial hypotension (simultaneous use is possible depending on achievement of necessary therapeutic effect).

Phenytoinum can promote emergence of bradycardia and arterial hypotension (depends on rate of administering and a dose), ergot alkaloids – to a gangrenosis and vasoconstriction.

Dopamine pharmaceutical is incompatible with oxidizers, alkaline solutions (inactivate a dopamine), thiamin (promotes B1 vitamin destruction), iron salts; let's combine with cardiac glycosides (the additive inotropic effect, increase in risk of arrhythmias of heart is possible – control of an ECG is necessary).

Terms and storage conditions

To store in protected from light, the place, unavailable to children, at a temperature of 8-25 °C.

Period of validity – 3 years.