Have you ever spent half your shift working to save a cardiac arrest patient only to have them die in the ICU from anoxic brain death? Of course. We all have. We have all seen it a lot!!! Getting return of spontaneous circulation (ROSC) is completely different from getting return of neurologic function (RONF). The difference between these two outcomes is two to five times higher for ROSC than for RONF. That means we, as emergency practitioners, admit a large numbers of cardiac arrest patients who ultimately die in the ICU from anoxic encephalopathy. What if we could change this? What if we could decide when we first start resuscitating the patient whether they have enough brain left to make our efforts worthwhile. This is where the concept of, “Time-Zero Neuroprognostication” comes into play. “Time-Zero” meaning intra-arrest or immediately at the time of ROSC and “Neuroprognostication” meaning predicting future neurological outcomes.
Imagine two different scenarios:
- an older patient with known severe dementia sustains an unwitnessed out of hospital cardiac arrest. The medics have done all the usual ACLS interventions as they bring the patient to your facility. With a simple bedside device, you determine that the brain has a less a 0.1% chance of recovery. You are able to reliably decide that the interventions are futile and pronounce the patient.
- The second scenario is a middle aged female who has a witnessed cardiac arrest with bystander CPR. Her downtime is 35 minutes when she presents to your ER. With use of the same device, you decide that she still has a good chance of having neurological recovery. You continue ACLS and ultimately achieve ROSC. She has a prolonged hospitalization but is ultimately discharged neurologically intact.
Both of these situations are still futuristic dreams, but we do have some exciting possibilities on the horizon to potentially make time-zero neuroprognostication a reality.
Current Neuroprognostication
You already do this. Currently, you neuroprognosticate every critically ill patient that presents to the ED. That is a core component of your ED or critical care training. You attempt to determine whether a patient should embark upon a “curative route” or a “palliative route,” and that decision is complex. You currently decide who to transport to the hospital after out-of-hospital cardiac arrest. You decide how long to continue CPR after cardiac arrest. You already do this!
These situations all incorporate cardiac and neuro-prognostication. You believe you have a grasp on making these decisions, but to what extent is that belief based on outcome-driven data versus unfounded gestalt? Termination of Resuscitation (TOR) guidelines (attached) provide some data about which patients to pronounce in the field, but even these are fraught with discrepancies. The traditional view of neuro-prognostication involves determination of brain function after ROSC. This typically involves a neurologist and/or intensivist. Unfortunately, there is very little prognostic indicators that can be assessed at the time of ROSC.
The Future of Neuro-Prognostication
The ideal scenario would involve rapid, noninvasive determination of neurologic function intra-arrest or immediately upon ROSC. Currently, two devices show some promise in this area. Bispectral Index Scores (BIS) have been explored, but are suppressed by patient sedation (Resuscitation 84 (2013) 794– 797 & Resuscitation 83 (2012) e193). Recent studies using Near Infrared Spectroscopy (NIRS) for peri-arrest neuro-prognostication have shown promise (Resuscitation 83 (2012) 46– 50 & Resuscitation 83 (2012) 11– 12).
Neuro-Prognostication and Decision to Stop Care
A major dilemma in resuscitation research is the substantial difference in when cessation of care occurs. If aggressive management is continued in one ICU for an average of 7 days and another for only 2 days, the survival of the patient will hinge upon location. When chest compression rate, epinephrine infusion, or even intra-arrest neuroprognostication devices are studied, outcomes will depend on the longevity of the ICU stay. Controlling for this variable can be difficult as even within hospitals this outcome can vary significantly.
