Pad size on cardioversion

Q: During external electric cardioversion which size of electrode pad is preferred (select one)

A) Bigger size
B) Smaller size


Answer: A

Larger size of electrode pad (usually 12-13 cm in diameter) provides larger paddle surface area, which results in decrease resistance and increase current and may cause less cardiac muscle necrosis.



References:

1. Thomas ED, Ewy GA, Dahl CF, Ewy MD. Effectiveness of direct current defibrillation: role of paddle electrode size. Am Heart J 1977; 93:463. 

2. Ewy GA, Horan WJ. Effectiveness of direct current defibrillation: role of paddle electrode size: II. Am Heart J 1977; 93:674. 

3. Dahl CF, Ewy GA, Warner ED, Thomas ED. Myocardial necrosis from direct current countershock. Effect of paddle electrode size and time interval between discharges. Circulation 1974; 50:956.