Non-glycoside cardiotonic drugs. Adrenergic and dopaminergic agents
In its chemical origin, dopamine is a precursor of noradrenaline biosynthesis and has a specific stimulating effect on dopamine receptors, and in large doses stimulates α- and β-adrenoceptors. Dopamine-Darnitsa increases peripheral vascular resistance (systemic vascular resistance, SVR), systolic blood pressure, heart rate, and cardiac output.
Shock or states that may lead to shock:
– heart failure caused by acute myocardial infarction (cardiogenic shock);
– severe infections (septic shock);
– postoperative shock;
– marked drop in blood pressure (severe hypotension) of any genesis;
– hypersensitivity reactions (anaphylactic shock).
Doses are selected individually by the physician, taking into account the shock severity, the patient's response to dopamine treatment, and adverse effects. To obtain the desired haemodynamic effect of dopamine, the dose for each patient should be carefully titrated.
The volume of circulating blood must be restored before starting treatment. Electrolyte balance should be monitored simultaneously with dopamine administration.
Unless otherwise prescribed by the physician, the following doses are recommended:
Adult patients, who may be likely to respond to moderate maintenance of cardiac function and blood circulation, may be given an infusion of dopamine at an initial dose of 2-5 mg/kg body weight per minute.
In this case, in severely ill patients the initial dose should be 5 mg/kg, and if necessary, it can be gradually increased (e.g. every 15-30 minutes) to 5-10 mg/kg body weight per minute to a maximum dose of 20-50 mg/kg body weight per minute.
Most patients are able to achieve a satisfactory state with doses of dopamine below 20 mg/kg body weight per minute. Drug administration at a dose of more than 20 mg/kg body weight per minute may be accompanied by a decrease in renal blood flow.
In case of worsening heart failure, dopamine should be administered as an infusion at a dose of not more than 50 mg/kg body weight per minute.