1994 Fiscal Year Final Research Report Summary
Study for elevating effect of defibrillation threshold by antiarrythmic drugs during the treatment of arrythmia
| Project/Area Number |
05454414
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Anesthesiology/Resuscitation studies
|
|---|
| Research Institution | University of Tsukuba |
|---|
Principal Investigator |
NAITO Hiroshi Inst.of Clin.Med., Univ.of Tsukuba Professor, 臨床医学系, 教授 (60045341)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OKUBO Naomitsu Inst.of Clin.Med., Univ.of Tsukuba Assistant Professor, 臨床医学系, 助手 (20223761)
TAKESHIMA Reiko Mito Saiseikai General Hosp.Chief Anesthetist, 医長 (30188180)
SATO Shigehito Inst.of Clin.Med., Univ.of Tsukuba Associate Professor, 臨床医学系, 助教授 (30143176)
|
|---|
| Project Period (FY) |
1993 – 1994
|
| Keywords | mexiletine / flecainide / defibrillation threshold / ventricular fibrillation / antiarrythmic drug / sudden cardiac arrest |
|---|
| Research Abstract |
Abstract of 1st year : Many of the antiarrhythmic drugs produce a rise in the ventricular defibrillation threshold (DFT). Although mexiletine has also been reported as the probable cause of a significant elevation of DFT,there has been no previous study ; therefore, the effect of mexiletine on DFT was investigated in the present study. The experiments were performed on ten mongrel dogs. Mexiletine 1,2,4,6, or 8 mg/kg was administered as the loading dose, followed by the same dose/kg per hour. In these five groups, fibrillation/defibrillation (F/D) trials were performed repeatedly every 10 minutes, until 60 minutes after starting the maintenance dose. F/D trials were also performed at 30,45, and 60 minutes after the completion of mexiletine infusion. Applying internal paddles to the heart, energies of 2,3,5,7,10,20, and 30 J maximum were used. The mexiletine concentration in each group changed from 0 to 6.11 mug/ml, DFE ranged from 2-10 J,and no statistical correlation was found between mexiletine concentration and DFT.We conclude that mexiletine does not induce an increase in DFT in dogs.
Abstract of 2nd year : The effect of mexiletine on DFT during continuous administration of flecainide was investigated in the 2nd year. The animals were prepared as same as 1st year. Flecainide 2 mg/kg was administered as the loading dose, followed by the same dose/kg per hour. Then, mexiletine 1,2,3,4,5 mg/kg was consecutively administered until the failure of defibrillation. F/D trials were performed in each phase. The minimal energy shock that caused defibrillation (DFT) increased according the increment dose of mexiletine. In conclusion, in a patient administered flecainide, we must be careful for administration of mexiletine in treating ventricular fibrillation.
|
Research Products
(1 results)
