When a child's heart stops, onset time of abnormal rhythms is crucialJune 01, 2006
Largest study of in-hospital cardiac arrest in children overturns conventional medical wisdom
Ventricular fibrillation, the life-threatening disordered heart rhythms that may accompany full cardiac arrest, occurs more frequently in children than commonly believed, according to a large national pediatric study.
Furthermore, not all ventricular fibrillation (VF) is the same, said study co-investigators Vinay Nadkarni, M.D., and Peter A. Meaney, M.D., M.P.H., specialists in Critical Care Medicine at The Children's Hospital of Philadelphia. They added that VF is more likely to be fatal if it is not the initial heart rhythm detected at the start of cardiac arrest, but instead develops later during the arrest, typically during resuscitation.
A research team from the American Heart Association's National Registry of Cardiopulmonary Resuscitation (CPR) analyzed records from more than 1,000 children who suffered cardiac arrests while in the hospital. The largest study by far of outcomes from VF in children, it appears in the June 1 issue of the New England Journal of Medicine. Researchers from Children's Hospital and from the University of Arizona led the study, which included records from 159 participating hospitals.
"This landmark in-hospital study challenges prevailing paradigms in pediatric cardiac critical care," said senior author Robert A. Berg, M.D., of the Steele Children's Research Center at the University of Arizona. "Abnormal rhythms were thought to be uncommon during cardiac arrests in children, occurring less than 10 percent of the time, but we found the occurrence to be 27 percent. When physicians applied shocks promptly from defibrillators, many of these children survived, and the vast majority of the survivors have good neurological outcomes."
"Secondly," continued Dr. Berg, "we learned that cardiac arrests due to initial shockable rhythms often have good outcomes, whereas cardiac arrests with shockable rhythms developing during resuscitation typically have poor outcomes. Now we have to learn what we can do to improve outcomes from the latter cases."
Of the 1,005 children who suffered in-hospital cardiac arrest, more than one in four (272 patients) had documented VF or tachycardia (rapid heart beats) that require shocks at some point during the arrest. In 104 of those patients VF or tachycardia occurred initially, while in 149 patients it occurred at a subsequent time during the arrest. Of the children with initial abnormal rhythms, 35 percent survived to hospital discharge, compared to 11 percent of children with subsequent abnormal rhythms.
The largest group of patients with cardiac arrest, 733 children, had no documented VF or tachycardia. A majority of the group, 602 patients, was known to have asystole (no heart contractions) or no pulse at the start of cardiac arrest. This group had intermediate outcomes: 27 percent survived to hospital discharge.
The researchers were surprised that this group with no VF had better outcomes than children with subsequent VF. Unlike patients with VF, shock delivery with defibrillators does not help patients with asystole or pulseless rhythms.
The question of why survival outcomes from subsequent VF were so low is interesting and requires more research, according to the researchers. One possible explanation, said Dr. Berg, is that children with subsequent VF have more severe underlying heart disease. Another possibility is that clinicians are less aware of the possibility of subsequent VF, and may not diagnose and treat it until it is recognized very late in resuscitation efforts. If this is the case, he added, better recognition, diagnosis and treatment of subsequent VF might improve survival.
The authors point out that, although outcomes may vary, the majority of children with cardiac arrest do not survive to hospital discharge. However, they stress that "CPR and advanced life support are certainly not futile," even among the group with the worst outcomes — children with subsequent VF and tachycardia.
Based partly on data reported by the National Registry of CPR, the American Heart Association recently issued new guidelines for CPR and emergency cardiovascular care, both for children and adults. "Our findings reinforce the concept that CPR with early recognition of shockable rhythms remains a most important aspect of successful cardiac resuscitation," added Dr. Nadkarni, "but clearly, we need to continue to develop, teach and implement better strategies using registries and networks that help us to discern key aspects of cardiac arrest."
Children's Hospital of Philadelphia
Related Cardiac Arrest Current Events and Cardiac Arrest News Articles
Study suggests new role for ECMO in treating patients with cardiac arrest and profound shock
Extracorporeal membrane oxygenation (ECMO), a procedure traditionally used during cardiac surgeries and in the ICU that functions as an artificial replacement for a patient's heart and lungs, has also been used to resuscitate cardiac arrest victims in Japan, Taiwan, and South Korea.
Research identifies infection and sepsis-related mortality hotspots across the US
In the past, researchers have sought to determine the geographic distribution of many life-threatening conditions, including stroke and cardiac arrest.
In Cleveland Clinic study, less than half of deaths after angioplasty result of procedure
Only 42 percent of the deaths occurring within 30 days of percutaneous coronary interventions (PCI) were attributable to complications from the procedure, according to a Cleveland Clinic study published online in the Journal of the American College of Cardiology.
And the beat goes on...: The reliable heartbeat of hibernators
At the current temperatures, all hibernators have probably emerged from their winter hibernation and are enjoying the warm weather.
Gene Offers Clues to New Treatments for a Harmful Blood Clotting Disorder
A gene associated with both protection against bacterial infection and excessive blood clotting could offer new insights into treatment strategies for deep-vein thrombosis -- the formation of a harmful clot in a deep vein.
Study finds survival from cardiac arrest highest in the operating room or post-anesthesia care unit
A University of Michigan study from the "Online First" edition of Anesthesiology found cardiac arrest was associated with improved survival when it occurred in the operating room (O.R.) or post-anesthesia care unit (PACU) compared to other hospital locations.
Beaumont doctors call for standardized, widespread training to reduce sudden cardiac arrest fatalities in schools
One of the leading causes of death in the United States is sudden cardiac arrest, which claims the lives of more than 325,000 people each year.
Ground-level ozone falling faster than model predicted
There is good news and better news about ground-level ozone in American cities. While dangerous ozone levels have fallen in places that clamp down on emissions from vehicles and industry, a new study from Rice University suggests that a model widely used to predict the impact of remediation efforts has been too conservative.
Changes needed to improve in-hospital cardiac arrest care, survival
Policy and practice changes by healthcare institutions, providers and others could greatly improve medical care and improve survival for people who have a sudden cardiac arrest in the hospital.
Life saving treatment for fire ant allergy under used
Two million Americans are allergic to insect stings, an allergy which sends more than 500,000 people to the emergency room annually.
More Cardiac Arrest Current Events and Cardiac Arrest News Articles