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Purpose of Review A review of American history is presented to understand how public policy has contributed to a disproportionate burden of disease in members of underrepresented groups. A review of research conducted in the Stroke Belt provides an opportunity to examine more closely traditional and non-traditional risk factors in an effort to consider strategies for change. Recent Findings A diverse physician workforce has been offered as a way of improving care for our increasingly diverse populace. Given the expected increased prevalence of stroke in communities of color and the impact of stress from discrimination on health, proactive strategies to promote inclusion and equity to support diversity in perioperative neuroscience is warranted. Summary Public policy rooted in structural racism has left marginalized groups economically and educationally disadvantaged with less access to health care. Mistrust and fear from ongoing discrimination compels the neuroscience community to broaden their approach for developing a more reassuring and supportive educational environment for patients and trainees.

Patients with hypertension, diabetes, and heart disease are at risk for chronic kidney disease and therefore require close monitoring of potassium (K+) levels in order to avoid some of the more concerning consequences of hyperkalemia. Medical therapy in these patients, which often includes angiotensin converting enzyme inhibitors, angiotensin receptor blockers, renin inhibitors, and mineralocorticoid receptor antagonists, while helpful in managing some of the aforementioned comorbidities and ameliorating chronic kidney disease in these patients, places them at increased risk for unwanted K+ elevations. Symptoms of hyperkalemia maybe nonspecific (fatigue, weakness, and gastrointestinal upset), requiring attention therefore to preoperative laboratory analysis to avert the potentially lethal intraoperative consequences of hyperkalemia like asystole and ventricular fibrillation. Emergency surgery in these patients after trauma complicated by crush injury is particularly challenging requiring that the anesthesiologist be well-versed in recognizing the signs of and managing intraoperative hyperkalemia.

Summary Indications for carotid endarterectomy (CEA) have been expanded recently, and a consensus statement has been made regarding these changes. However, the debate regarding the “ideal” anesthetic for CEA remains on-going. This study was designed to evaluate the actual anesthetic techniques used by anesthesiologists for CEA. A total of 426 1-page questionnaires were mailed to all current (1995) members of the Society of Neurosurgical Anesthesia and Critical Care (SNACC). Of these, 216 (50.7%) were completed and returned. The majority of these respondents (84.7%) administered general anesthesia (GA) for CEA. Regional anesthesia (RA) was the anesthetic method of choice for 16.7%, whereas 2.8% each chose either local anesthesia (LOC) or a combined regional/general (RA/GA) technique. Despite the controversial role of nitrous oxide in neuroanesthesia, 74.6% of those returning the survey use nitrous oxide during CEA. Intraoperative neuromonitoring use was reported by 90% of the respondents, with the electroencephalography (EEG) the favored modality (67.5%). Specific intraoperative neuroprotective measures were provided by only 22.2% of all respondents, with barbiturates as the favorite method (50.0%). The technique of intraoperative hypertension is practiced by a majority of those surveyed (61.1%), with the most common target blood pressures being either preoperative baseline or preoperative baseline plus 20%. Although there is some trend towards nonintensive care setting for postoperative care, the intensive care remains the location of choice for overnight care of CEA patients (71.8%). The results of this study show that despite arguments for RA over GA, the majority of anesthesiologists surveyed choose GA for CEA.

The authors discuss the role of intravenous anesthetic agents in brain protection. The newer intravenous anesthetics, etomidate and propofol, have been proposed as neuroprotective agents. Thiopental remains the drug of choice, however, for use prior to intraoperative ischemic events. The anesthetic ketamine presents surprising similarities to other N-methyl-D-aspartate receptor inhibitors, but remains controversial in its use in neurologically compromised patients.

✓ Blood temperature at the jugular bulb was monitored in 10 patients undergoing neurovascular procedures that used induced mild hypothermia, and its correlation with surface brain, core, and peripheral temperatures was determined. The study was motivated by the difficulty encountered in directly measuring global brain temperature and the poor correlations between various core and peripheral sites temperatures and brain temperature, particularly during deep hypothermia. Although not statistically significant, previous studies have suggested a trend toward higher brain temperatures. Temperatures from the jugular bulb (collected using a No. 5 French Swan—Ganz catheter) as well as from subdural, pulmonary artery, esophagus, tympanic membrane, and bladder sites were analyzed during three surgical conditions: prior to incision, with the dura open, and after closure of the dura. No complications related to placement of the jugular bulb catheter, induced hypothermia, or temperature monitoring were seen. The authors found that jugular bulb temperature was similar to pulmonary artery and esophageal temperatures; although prior to incision it tended to be higher than that found at the pulmonary artery, most commonly by 0.2°C. Surface brain temperature was cooler than all other temperatures (p < 0.05), except that of the tympanic membrane, and was particularly sensitive to environmental variations. Finally, as has been shown by others, bladder temperature lagged substantially behind core temperatures particularly during rapid cooling and rewarming of the patient. In summary, monitoring of jugular bulb temperature is a feasible technique, and temperatures measured in the jugular bulb are similar to core temperatures.

The primary objective of this study was to evaluate the electrophysiologic effects of large-dose propofol, used as the sole anesthetic in patients with epilepsy. Nine patients with medically intractable complex partial epilepsy undergoing a three-stage approach to the surgical management of epilepsy were recruited. State I involved placement of the intracranial electrode array, while Stage II consisted of extraoperative localization of the seizure focus. The patients were studied during induction of anesthesia for Stage III (removal of electrodes and resection of seizure focus). Unpremedicated patients were induced with a propofol infusion (0.5 mg.kg-1.min-1) until one of the following occurred: 1) electrical seizure activity, 2) burst suppression, or 3) total dose of 10 mg/mg. Electrocorticography (ECoG) was recorded continuously during this period. Two patients were excluded from the study after experiencing delayed awakening after the Stage I procedure. Both had received propofol along with other anesthetics. No ECoG evidence of seizure activity was detected in the seven patients completing the study. Burst suppression was attained in six patients using a mean dose of 5.7 mg/kg +/- 2.6. We conclude that large dose propofol alone does not trigger electrical epileptiform activity on the ECoG of seizure patients.