By Scott Woolf, DO, (left) Sydney Moseley, MD, (center) Hussein Alshammari, MD (center) and Fawaz Al-Mufti, MD1 (right)
1 Department of Neurology and Neurosurgery, Westchester Medical Center at New York Medical College
The authors have no actual or potential conflict of interest in relation to the topics discussed in this column. This article may discuss non-FDA-approved devices and “off-label” uses. The NCS and Currents do not endorse any particular device.
Clinical, subclinical and non-convulsive seizures (NCSZs) are commonplace in critically ill patients — and even more common in patients in the neuro ICU. Therefore, a means to more rapidly and readily identify and treat such cases should be considered, studied and subsequently implemented.
Quantitative Continuous Electroencephalography
Quantitative continuous electroencephalography (qEEG) records and compresses EEG information into simplified data patterns of frequencies, amplitude, power and rhythm. Current programs, such as density spectral array (DSA) and compressed spectral array (CSA), enable seizure detection via color (instead of waveforms) from long-term EEG data.
An interpretive software program could alert staff that changes have occurred, which would enable a rapid course of action without immediately requiring a trained electroencephalographer to interpret the raw data, thereby treating in a prompt and timely manner. Since studies have shown EEG interpretation having a statistically high rate of misreading, this also removes the initial variable of human error in reading and interpreting EEGs. One study found that epilepsy has a misdiagnosis estimated percentage of 30%. That said, cEEG has been become more available and portable over the past few decades and has high potential for utility in the ICU. This use includes patient demographics in which suspected seizure threshold is lower, as found in patients with stroke (ischemic or hemorrhagic), traumatic brain injury and in primary seizure disorders.
The “Brain Stethoscope”
Similar to quantitative continuous electroencephalography (qEEG), the brain stethoscope is a clinical tool that has been developed to allow for rapid analysis of brain activity and prompt treatment of aberrant rhythms. Similar to a stethoscope used to auscultate the heart and lungs, the brain stethoscope is able to be used by healthcare professionals with various levels of training to evaluate brain activity.
The brain stethoscope is a 10-lead portable EEG device that converts EEG waveform data to sounds that can be interpreted by the user at the bedside. Brain stethoscope setup time is faster than cEEG — 36 minutes versus 1.77 hours respectively. The brain stethoscope was also associated with more accurate treatment of patients with electrographic seizure and decreased erroneous treatment of patients without electrographic seizure when compared with independent epileptologist’s interpretation of the same EEG waveforms. Given these findings, the brain stethoscope would be a valuable asset to the have in the neuro ICU setting and could increase the speed and accuracy with which seizures are diagnosed and treated.
These devices could change to way the neuro ICU and its staff interfaces with emerging technologies for patient care. Additional screens, alarms and software programs would need to be installed. Staff would need to be trained and educated on use and limitations of these modalities. The addition of said programs would also add to an already sensory overloaded ICU system. A cost-benefit analysis would have to validate said technologies role if these programs are to be widely implemented and distributed. Though it is exciting to consider the addition of advanced diagnostic modalities in the treatment and management of neuro ICU patients, some barriers must be addressed and overcome.
In conclusion, though these technologies are not a perfect solution to electrographic findings on EEG, and epileptologists are still very much necessary in the interpretation and management of EEG correlates, advanced EEG technology is likely underutilized in the neuro ICU and should be under consideration as another so-called vital sign monitor in that setting. This can be done using a multidisciplinary approach consisting of the interpretive software, ICU nursing staff, critical care physicians and a neurologist.
Time and resources may be saved by using interpretive software that enables someone without encephalography training to recognize abnormalities, prompting them to alert the physicians when seizure activity is suspected. This cannot practically be done using conventional long-term video bedside cEEG monitoring. Therefore, a strategic and systematic approach should be entertained to address the problem of unrecognized seizures and/or concerning EEG patterns. Further studies and trials may be done to determine if this approach would improve overall outcomes in the neuro ICU patient population.
- Kramer AH, Kromm J. Quantitative Continuous EEG: Bridging the Gap Between the ICU Bedside and the EEG Interpreter. Neurocrit Care. 2019 Feb 20.
- Kubota Y, Nakamoto H, Egawa S, Kawamata T. Continuous EEG monitoring in ICU. J Intensive Care. 2018 Jul 17
- Collins N. Stanford researchers listen for silent seizures with "brain stethoscope" that turns brain waves into sound. Stanford News
- Hobbs K, Mlynash M, Gururangan K. The Brain Stethoscope: Instant Seizure Detection by Sonification of EEG in the ICU. Abstract in American Epilepsy Society.