J Korean Pediatr Soc.  2001 Feb;44(2):177-184.

The Relationship between Change of Cardiac Function and Systemic Oxygen Consumption according to the Dose of Dopamine in the Rabbit

• Park HJ
• Yoon SH
• Choi BS
• Choi JH
• Kim KT
• Kim SY
• Nam SO
• Lee BL

Abstract

PURPOSE: We'd like to know the relationship between the changes of cardiac function and systemic O2 consumption according to the increasing dose of dopamine.
METHODS
Ten rabbits(from 2kg to 2.8kg) were used in this experiment. Anesthesia was induced with intraperitoneal pentobarbital sodium(35mg/kg) and tracheostomy was done. It was maintained by ventilation with a mixture of 1-3% halothane and 67-69% oxygen. Polyvinyl catheters were inserted into the femoral artery and vein and to check blood pressure and arterial blood gas analysis during the surgical procedure. Two other catheters were inserted into the internal carotid artery and external jugular vein and advanced into left ventricle and right atrium to check the pressure of each chamber, LV maximal dP/dt and to obtain blood samples of each chamber. Thoracotomy was done to expose aorta and coronary artery to check the cardiac output and coronary blood flow. We injected dopamine every 10 minutes according to the scheduled dose through external jugular vein and recorded heart rate, cardiac output, aortic pressure, maximal dP/dt, coronary blood flow by computer. Systemic O2 consumption was calculated by Fick method
RESULTS
The heart rate and mean aortic pressure increased slowly according to the dose of dopamine from 20 microgram/kg/min. The cardiac otuput the maximal dP/dt and coronary blood flow was not changed until 5 microgram/kg/min, but from 7.5microgram/kg/min, it increased according to the dose of dopamine.
CONCLUSION
Dopamine was a powerful inotrophic agent without increasing the systemic O2 consumption until 20microgram/kg/min, but systemic O2 consumption increased markedly at more than 20 microgram/kg/min of dopamine.

Keyword

Heart rate; Mean aortic pressure; Cardiac output; Maximal dP/dt; Coronary blood flow; Systemic O2 consumption; Dopamine

MeSH Terms

Anesthesia
Aorta
Arterial Pressure
Blood Gas Analysis
Blood Pressure
Cardiac Output
Carotid Artery, Internal
Catheters
Coronary Vessels
Dopamine*
Femoral Artery
Halothane
Heart Atria
Heart Rate
Heart Ventricles
Jugular Veins
Oxygen Consumption*
Oxygen*
Pentobarbital
Polyvinyls
Thoracotomy
Tracheostomy
Veins
Ventilation
Dopamine
Halothane
Oxygen
Pentobarbital
Polyvinyls