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

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.

Diagnosis of Pancreatic Tumors: Comparison of MR Pancreatograp hy (MRP )and Endoscopic Retrograde Pancreatography(ERP)

PURPOSE: Magnetic resonance pancreatography(MRP) is a non-invasive imaging technique for visualization of the pancreatic duct system, and is similar to those obtained by means of endoscopic retrograde pancreatography (ERP). To determine the role of MRP in the diagnosis of pancreatic tumors, the diagnostic confidence and imaginal difference of MRP and ERP were compared. MATERIALS AND METHODS: Twenty patients (13 male and 7 female, mean age 59 years) with pancreatic tumors underwent MRP and ERP. The former involved the use of a single shot fast spinecho sequence on a 1.5T system. All images were retrospectively reviewed by a radiologist and a gastroenterologist, working together. Both MRP and ERP were compared for separate visualization of the head, body and tail portion of the pancreatic duct, and scored as excellent (4), good (3), fair (2), poor (1), or no visualization (0). In addition, the overall diagnostic confidence of both modalities was graded subjectively from non-diagnoses (0) to definite information (4). The final diagnoses derived from surgical findings (n=9) or imaging findings and clinical follow-up (n=7) were as follows : pancreatic cancer (n=12), mucin-producing pancreatic cancer (n=2), mucinous ductectatic tumor (n=4), serous cystadenoma (n=2). To assess the statistical significance of difference, the paired t-test was used. RESULTS: Mean scores of visualization of the pancreatic duct by MRP and ERP were 2.91 and 3.15 in the pancreatic head (p=NS), 3.11 and 2.18 in the pancreatic body (p=NS), and 3.07 and 1.09 in the pancreatic tail (p<0.01). The mean score of diagnostic confidence was 4.03 for MRP and 2.51 for ERP, a statistically significant difference (p <0.05). In 11 patients with obstruction of the pancreatic duct due to malignant lesions, MRP visualized the duct both proximally and distally to the site of obstruction, while ERP visualized only the distal duct to the site of obstruction. MRP was also better at defining the extent of tumor by visualization of surrounding pancreatic parenchyma. In two cases of serous cystadenoma with lack of communication between the pancreatic duct and cystic neoplasm, MRP depicted the lesion clearly whereas ERP showed no information. CONCLUSION: MRP is better than ERP at visualizing the of pancreatic duct proximal to obstruction, assessment of tumoral extent, and diagnosis of a cystic neoplasm which does not communicate with the pancreatic duct.