Survey finds shortcomings in assessment of neurologic function after cardiac arrest

More than a third of clinicians said they used absent corneal reflexes and absent pupillary reflexes at 24 hours to assess patient prognosis, even though guidelines recommend waiting 72 hours.

Many physicians use outdated practices to assess the neurological function of patients after cardiac arrest, according to a recent survey of specialists.

The web-based survey gathered data from 762 members of the Neurocritical Care Society, Society of Critical Care Medicine, and American Academy of Neurology to assess current practices in neuroprognostication. The respondents came from 22 countries, although the majority were in the U.S., and all reported caring for successfully resuscitated unconscious cardiac arrest patients. Results were published by Critical Care Medicine on Nov. 18.

More than a third of the respondents said they used absent corneal reflexes (33.5%) and absent pupillary reflexes (36.2%) at 24 hours to assess patient prognosis. Current guidelines recommend waiting 72 hours. Most of the respondents (87%) considered absent motor response or extensor posturing to be very or critically important prognostic indicators. The study authors noted that although these used to be considered robust predictors, more recent research has found unacceptably high false-positive rates, so the use of these indicators alone is no longer recommended.

Asked to choose which tests were very or critically important, the most respondents chose neurologic examination (97.7%), followed by myoclonic status epilepticus (80.3%), brain MRI (70.2%), electroencephalography (68.4%), head CT (62.7%), and median nerve somatosensory evoked potentials (SSEP, 53.5%). The study authors noted that SSEP have been found to have a higher predictive value than myoclonic status epilepticus or imaging. The survey also found that up to 25% of the respondents would give a poor prognosis and definitive recommendations sooner than is supported by the evidence.

“Neuroprognostic approaches to hypoxic-ischemic encephalopathy vary among physicians and are often not consistent with current guidelines. The overall inconsistency in approaches and deviation from evidence-based recommendations are concerning in this disease state where mortality is so integrally related to outcome prediction,” the authors concluded. They called for educational efforts to inform clinicians about the latest evidence and guidelines.

The July ACP Hospitalist covered the latest evidence on predicting recovery after cardiac arrest, based on an expert lecture at the American Academy of Neurology's annual meeting.