Dallas, Texas - According to new research in the American Heart Association’s journal Circulation, resuscitation and post-resuscitation care after cardiac arrest have both improved but mortality remains high. Most of the poor outcomes and deaths of cardiac arrest survivors have been attributed to widespread brain injury, but inaccurate neurologic prognostication, resulting in withdrawal of life-sustaining treatment and deaths, may significantly bias clinical studies, leading to failure in detecting the true study outcomes.

The vast majority of patients who are successfully resuscitated from cardiac arrest are diagnosed after their resuscitation with coma or with an altered level of consciousness due to lack of oxygen to the brain before resuscitation. Most deaths associated with brain injury after cardiac arrest result from active withdrawal of life-sustaining treatment because a poor neurologic outcome is predicted. While most deaths in patients initially resuscitated from cardiac arrest are attributed to brain injury, only about 10% of these deaths meet clinical criteria for brain death.

Determining prognosis after successful resuscitation is a central component of post-cardiac arrest care. Unfortunately, the quality of science that supports prediction of outcome in comatose survivors of cardiac arrest is low. This low quality of science leads to error in predictions of outcomes that are likely to have a negative impact on patient care and clinical trials.

The American Heart Association has released a scientific statement that provides a roadmap for how studies in the prediction of outcomes ought to be undertaken so that quality will be improved, which may result in better patient care and improvement in clinical trials. The statement provides suggestions to improve the scientific quality of neurologic prognostication studies in comatose adult and pediatric survivors of cardiac arrest.

“At the current state of affairs, we have to acknowledge the limitations in our practices in this area because we don’t have high-quality science to back our decision-making. We owe it to patients and families to ensure we are doing the best to both not prolong unnecessary suffering while balancing that with not withdrawing care too soon if the person has the potential to recover with a reasonably good quality of life,”2 said Romergryko G. Geocadin, MD, Professor of Neurology at Johns Hopkins Hospital and author of the new scientific statement published in the American Heart Association journal Circulation.

Examples of the suggestions in the statement include:

• Create index tests based on neurologic functions that are directly related to functional outcomes and contribute to quality of life for survivors
• Provide summary measures of accuracy and precision for clinical studies
• Specify measures of functional outcome and cause of death differentiated as cardiovascular or neurologic
• Target timing of primary and secondary outcome assessments
• Consider prearrest lifestyle and comorbidity factors

Relevant stats: 

• There are about 326,200 out-of-hospital cardiac arrests and 209,000 in-hospital cardiac arrest each year in the U.S.
• The survival to hospital discharge in 2016 was 12% for out-of-hospital cardiac arrests and 25% for in-hospital cardiac arrests.
• Survival with good neurologic outcome for out-of-hospital is 8%.

Co-authors are  Clifton W. Callaway, MD, PhD; Ericka L. Fink, MD, MS; Eyal Golan, MD; David M. Greer, MD, MA, FAHA; Nerissa U. Ko, MD, MAS; Eddy Lang, MD; Daniel J. Licht, MD; Bradley S. Marino, MD, MPP, MSCE; Norma McNair, PhD, RN, FAHA; Mary Ann Peberdy, MD; Sarah M. Perman, MD, MSCE; Daniel B. Sims, MD; Jasmeet Soar, MA, MB, BChir; Claudio Sandroni, MD