Kids in cardiac arrest get suboptimal shock doses
Last Updated: 2010-12-22 16:25:02 -0400 (Reuters Health)
By Dave Levitan
NEW YORK (Reuters Health) - National guidelines that stipulate shock doses for bringing kids out of cardiac arrest are off the mark, a new study shows - and an alternative dose tested in the study didn't work too well, either.
"The optimal pediatric defibrillation dose remains unknown," the researchers say.
The American Heart Association advises an initial shock dose of 2 J/kg for children with ventricular fibrillation or pulseless ventricular tachycardia and cardiac arrest.
But the study's authors say this recommendation is based only on "a limited study, anecdotal experience, and expert consensus."
"Because recent investigations by ourselves and others indicated that 2 J/kg is often ineffective at terminating fibrillation, and because success at termination is dose-dependent, we hypothesized that (a) higher dose (4 J/kg) would be more effective," said senior author Dr. Robert Berg of Children's Hospital of Philadelphia in e-mail to Reuters Health.
Dr. Berg and colleagues analyzed 2000-2008 data from the National Registry of Cardiopulmonary Resuscitation on 266 children with 285 in-hospital events.
According to their report, published online December 20th in Pediatrics, fibrillation was terminated after the initial shock in 152 events (53%). One hundred seventy-three children survived the event (65%), although only 61 survived to discharge (23%). The researchers compared children who received a shock dose of 2 J/kg to historical controls and found a significantly worse rate of VF termination in the new cohort (56% vs. 91%; p<0.001).
However, there was no difference in fibrillation termination rates between the 2 J/kg or 4 J/kg doses. Children who received an initial dose of 4 J/kg, though, had lower odds ratios for return of spontaneous circulation (OR 0.41) and event survival (OR 0.42).
Dr. Berg said the results did come as a disappointment. "But it is important to re-emphasize that we do not know why the higher dose (4 J/kg) was administered," he said. "Did the physicians provide a higher dose for sicker children, or was the non-recommended dose (4 J/kg) used by a team that deviated from recommended guidelines in other ways and perhaps provided inadequate resuscitation efforts?"
Unfortunately, the database used for this study did not provide answers to these questions, leaving the optimal dosing for in-hospital defibrillation unknown. The group is planning further studies to fill in that gap.
SOURCE:http://link.reuters.com/meh43r
Pediatrics 2011.
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