Dr. Romergryko Geocadin is involved with numerous projects, all of which revolve around translational research in neurocritical care and the devastating neurologic injuries that occur while the brain is in a comatose state. Coma can be brought about by cardiac arrest, trauma, or mass lesions in the brain. Most of Dr. Geocadin’s work since the mid-1990s has been in the area of global cerebral ischemia after cardiac arrest. In an animal model, he and his colleagues study the progress of neurologic injury and recovery that mimic the actual clinical situation in an effort to understand how the brain revives early after injury. They seek to discover what is actually happening to the brain and how it regains consciousness from a state of unresponsiveness (a state of coma).
Dr. Geocadin entered into this line of research when he was a clinical fellow, and with support from a Career Development Grant from the American Academy of Neurology, he was able to begin to collect human data and develop novel measures by using quantifying EEG (QEEG) during periods of recovery that were not being studied elsewhere. With a translational grant from the NIH, he collaborated with Biomedical Engineering staff and others, subsequently obtaining an NIH R43 grant and collecting data via phase 1 and phase 2 trials. Their completed phase 2 trial (with 30 patients) showed that the measures that had been developed in rats robustly predicted and tracked recovery from an unresponsive state to arousal in humans after cardiac arrest and resuscitation. They are currently conducting a phase 2B (R44) multicentered trial in which they are tracking the effects of hypothermia on resuscitation from coma. In this area, Dr. Geocadin is also working on a collaborative grant proposal that would include representation from neurology, neurocritical care/ACCM, biomedical engineering, and cardiology.
In a related project, Dr. Geocadin and his colleagues are working toward developing therapeutic hypothermia to control the neurologic injury associated with cardiac arrest. Using QEEG technology in rodents, they are able to track the effects of temporary manipulation of the brain—hypothermia, normothermia, and hyperthermia. The goal is to effectively titrate hypothermia for better outcomes and then to translate these protocols to humans.
The Geocadin laboratory is also working on coma in relation to mass lesions in the brain. The most common mass lesions result from brain herniation syndromes. In experimental models, the intracranial pressure of animals is increased via balloon inflation and then measured. The group has also developed techniques by which to measure injury directly on the brain using noninvasive somatosensory-evoked potentials (SSEPs, a way of recording evoked, or stimulated, brain responses). They have shown that rapid intracranial expansion of a mass lesion and the associated increases in intracranial pressure correlates very well with changes in SSEPs. They are currently studying the role of early and frequent SSEPs in people with mass lesions to see if they can track progression of injury and recovery.
Dr. Geocadin is beginning a collaboration with the trauma service at Hopkins to rigorously study the process of coma in patients with traumatic brain injury (TBI). Most clinicians focus on Glasgow Coma Scale scores and clinical manifestation to assess the patient’s conscious state. However, the actual neurotomic substrate that presents itself as changes in consciousness has never been rigorously validated. These collaborators are utilizing a database of patients with TBI to identify the parts of the brain that are affected by TBI, understand the brain injury process in relation to coma after TBI, and develop novel, noninvasive measures to track the injury process in real time. They seek to determine if the measures that have been developed in cardiac arrest, global cerebral ischemia, etc., can be used in comatose patients with TBI.
Lastly, Dr. Geocadin seeks to study the changes in mental status and levels of consciousness in relation to encephalitis. His efforts were essential to the recent establishment of the Encephalitis Center at Hopkins. The big problem is the alternation in levels of consciousness from coma to seizures. Patients with encephalitis have altered levels of consciousness. In the best conditions, only ~40% have determinable etiology; the rest are unknown. The Encephalitis Center was formed to create a better process by which to diagnose these patients and to provide them with good neurocritical care.
Dr. Geocadin’s long-term goal is twofold: (1) to be instrumental in developing a scientifically validated, clinically relevant, and user-friendly monitoring device that can be operated by any member of the ICU or ER team for bedside neuromonitoring of brain injury after resuscitation from cardiac arrest, so that they can (relative to EKGs and pulse oximeters) tell real-time injury, stratify injury levels to match optimal therapies, track the responses to those therapies, and predict functional outcomes; and (2) to create a multifaceted, translational center for neurocritical care, where all aspects of his research can be focused toward the delivery of quality care to patients with neurocritical issues.