Dopamine Concentration and Hemodynamic Effects according to the Methods of Dopamine Dilution

Kim, Jin Hee; Park, Hee Pyung; Ham, Byung Moon; Kim, Yong Lak; Jeon, Yoon Seok; Seo, Jung Hoon

Abstract

BACKGROUND
Incorrect infusion of dopamine can be potentially life threatening. If the actual volume of a 100 ml intravenous bag or bottle used to mix dopamine solutions is greater than the labeled volume, overdilution of dopamine can occur, resulting in ineffective hemodynamic response. To determine the significance of dopamine overdilution induced by the excessive volume, dopamine concentration and hemodynamic effect were compared in the manually mixed dopamine and the manufactured premixed dopamine. METHODS: For 5% dextrose water (D5W) 100 ml intravenous bottle mixed with 160 mg (4 ml) of dopamine (group 1), D5W 96 ml mixed with 160 mg of dopamine (group 2), premixed dopamine with 1.6 mg/ml of concentration manufactured 2 months ago (group 3), premixed dopamine with 1.6 mg/ml of concentration manufactured 6 months ago (group 4), and D5W 100 ml intravenous bottle mixed with 160 mg (4 ml) of dopamine after removal of 4 ml dextrose water (group 5), dopamine concentration was measured by High performance liquid chromatography (HPLC). Hemodynamic data was obtained from 10 mongrel dogs for each group at baseline (T1), 15 minutes after dopamine infusion at a rate of 3 microgram/kg/min (T2), 8 microgram/kg/min (T3), and 15 microgram/kg/min (T4). RESULTS: Dopamine concentrations of group 1, 2, 3, 4, and 5 were 1.51+/- 0.09, 1.60 +/- 0.10, 1.63 +/- 0.06, 1.57+/- 0.08 and 1.57+/- 0.07 mg/ml, respectively. Group 1 showed a significantly low concentration (p< 0.05). There was no significant differences in all hemodynamic data between group 1, 2, 3, and 4. In group 1, however, there was no significant increase in both mean blood pressure at T4 and mixed venous oxygen saturation at T3 compared with T1. CONCLUSIONS: The actual volume of D5W in 100 ml intravenous bottle is greater than the labeled, and therefore can cause significant overdilution of dopamine. Premixed dopamine, however, has the same concentration and hemodynamic effects as the dopamine mixed manually but precisely.