Transthoracic defibrillation: effect of sternotomy on chest impedance
RE Kerber,
S Vance,
SJ Schomer,
DJ Mariano,
and
F Charbonnier
Cardiovascular Division, University of Iowa Hospital, Iowa City 52242.
The purpose of this study was to determine the effect of sternotomy on transthoracic impedance, a major determinant of current flow and defibrillation success. Transthoracic impedance was determined by using a validated test-pulse technique that does not require actual shocks. Seventeen patients undergoing median sternotomy were studied prospectively. Transthoracic impedance was determined before operation, 3 to 5 days after operation and (in eight patients) greater than or equal to 1 month after operation. When measured using paddle electrodes placed in the standard apex-right parasternal defibrillating position, transthoracic impedance declined after sternotomy in all patients, from 77 +/- 18 to 59 +/- 17 omega (p less than 0.01); smaller declines were demonstrated by using other electrode positions. Transthoracic impedance remained below the preoperative level in the eight patients who underwent a second set of measurements at least 1 month after operation. Six normal subjects not undergoing sternotomy underwent serial transthoracic impedance measurements at least 5 days apart; mean transthoracic impedance did not change. It is concluded that transthoracic impedance declines after sternotomy. At any operator-selected energy level a higher current flow will result after sternotomy; this may facilitate postoperative defibrillation.
This article has been cited by other articles:
|
|
|
|
 
J. Dunning, A. Fabbri, P. H. Kolh, A. Levine, U. Lockowandt, J. Mackay, A. J. Pavie, T. Strang, M. I. M. Versteegh, S. A. M. Nashef, et al.
Guideline for resuscitation in cardiac arrest after cardiac surgery
Eur J Cardiothorac Surg,
July 1, 2009;
36(1):
3 - 28.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
T P Mathew, A Moore, M McIntyre, M T Harbinson, N P S Campbell, A A J Adgey, and G W N Dalzell
Randomised comparison of electrode positions for cardioversion of atrial fibrillation
Heart,
June 1, 1999;
81(6):
576 - 579.
[Abstract]
[Full Text]
|
|
|
|
|
|
|
P. C. Fotuhi, R. E. Ideker, S. F. Idriss, R. L. Callihan, R. G. Walker, and E. U. Alt
Influence of Epicardial Patches on Defibrillation Threshold With Nonthoracotomy Lead Configurations
Circulation,
November 15, 1995;
92(10):
3082 - 3088.
[Abstract]
[Full Text]
|
|
|
|
