Corticothalamic Connectivity in Aneurysmal Subarachnoid Hemorrhage: Relationship with Disordered Consciousness and Clinical Outcomes.

BACKGROUND: We present an exploratory analysis of the occurrence of early corticothalamic connectivity disruption after aneurysmal subarachnoid hemorrhage (SAH) and its correlation with clinical outcomes. METHODS: We conducted a retrospective study of patients with acute SAH who underwent continuous electroencephalography (EEG) for impairment of consciousness. Only patients undergoing endovascular aneurysm treatment were included. Continuous EEG tracings were reviewed to obtain artifact-free segments. Power spectral analyses were performed, and segments were classified as A (only delta power), B (predominant delta and theta), C (predominant theta and beta), or D (predominant alpha and beta). Each incremental category from A to D implies greater preservation of corticothalamic connectivity. We dichotomized categories as AB for poor connectivity and CD for good connectivity. The modified Rankin Scale score at follow-up and in-hospital mortality were used as outcome measures. RESULTS: Sixty-nine patients were included, of whom 58 had good quality EEG segments for classification: 28 were AB and 30 were CD. Hunt and Hess and World Federation of Neurological Surgeons grades were higher and the initial Glasgow Coma Scale score was lower in the AB group compared with the CD group. AB classification was associated with an adjusted odds ratio of 5.71 (95% confidence interval 1.61-20.30; p < 0.01) for poor outcome (modified Rankin Scale score 4-6) at a median follow-up of 4 months (interquartile range 2-6) and an odds ratio of 5.6 (95% confidence interval 0.98-31.95; p = 0.03) for in-hospital mortality, compared with CD. CONCLUSIONS: EEG spectral-power-based classification demonstrates early corticothalamic connectivity disruption following aneurysmal SAH and may be a mechanism involved in early brain injury. Furthermore, the extent of this disruption appears to be associated with functional outcome and in-hospital mortality in patients with aneurysmal SAH and appears to be a potentially useful predictive tool that must be validated prospectively.

Hypertonic Saline is Superior to Mannitol for the Combined Effect on Intracranial Pressure and Cerebral Perfusion Pressure Burdens in Patients With Severe Traumatic Brain Injury.

BACKGROUND: Hypertonic saline (HTS) and mannitol are effective in reducing intracranial pressure (ICP) after severe traumatic brain injury (TBI). However, their simultaneous effect on the cerebral perfusion pressure (CPP) and ICP has not been studied rigorously. OBJECTIVE: To determine the difference in effects of HTS and mannitol on the combined burden of high ICP and low CPP in patients with severe TBI. METHODS: We performed a case-control study using prospectively collected data from the New York State TBI-trac® database (Brain Trauma Foundation, New York, New York). Patients who received only 1 hyperosmotic agent, either mannitol or HTS for raised ICP, were included. Patients in the 2 groups were matched (1:1 and 1:2) for factors associated with 2-wk mortality: age, Glasgow Coma Scale score, pupillary reactivity, hypotension, abnormal computed tomography scans, and craniotomy. Primary endpoint was the combined burden of ICPhigh (> 25 mm Hg) and CPPlow (< 60 mm Hg). RESULTS: There were 25 matched pairs for 1:1 comparison and 24 HTS patients matched to 48 mannitol patients in 1:2 comparisons. Cumulative median osmolar doses in the 2 groups were similar. In patients treated with HTS compared to mannitol, total number of days (0.6 ± 0.8 vs 2.4 ± 2.3 d, P < .01), percentage of days with (8.8 ± 10.6 vs 28.1 ± 26.9%, P < .01), and the total duration of ICPhigh + CPPlow (11.12 ± 14.11 vs 30.56 ± 31.89 h, P = .01) were significantly lower. These results were replicated in the 1:2 match comparisons. CONCLUSION: HTS bolus therapy appears to be superior to mannitol in reduction of the combined burden of intracranial hypertension and associated hypoperfusion in severe TBI patients.

Association of Seizure Occurrence with Aneurysm Treatment Modality in Aneurysmal Subarachnoid Hemorrhage Patients.

BACKGROUND: Data on new-onset seizures after treatment of aneurysmal subarachnoid hemorrhage (aSAH) patients are limited and variable. We examined the association between new-onset seizures after aSAH and aneurysm treatment modality, as well their relationship with initial clinical severity of aSAH and outcomes. METHODS: This is a retrospective cohort study of all aSAH patients admitted to our institution over a 6-year period. 'Seizures' were defined as any observed clinical seizure or electrographic seizure on continuous electroencephalogram (cEEG) recordings, as determined by the reviewing neurophysiologist. Subgroup analyses were performed in low-grade (Hunt-Hess 1-3) and high-grade (Hunt-Hess 4-5) patients. Outcomes measures were Glasgow Coma Score (GCS) at intensive care unit (ICU) discharge and modified Rankin Scale (mRS) at outpatient follow-up. RESULTS: There were 282 patients with aSAH; 203 (72.0%) suffered low-grade and 79 (28%) high-grade aSAH. Patients were treated with endovascular coiling (N = 194, 68.8%) or surgical clipping (N = 66, 23.4%). Eighteen (6.4%) patients had seizures, of whom 10 (5.5%) had aneurysm coiling and 7 (10.6%) underwent clipping (p = 0.15). In low-grade patients, seizures occurred less frequently (p = 0.016) and were more common after surgical clipping (p = 0.0089). Seizures correlated with lower GCS upon ICU discharge (p < 0.001), in clipped (p = 0.011) and coiled (p < 0.001) patients and in low-grade aSAH (p < 0.001). Seizures correlated with higher mRS on follow-up (p < 0.001), in clipped (p = 0.032) and coiled (p = 0.004) patients and in low-grade aSAH (p = 0.003). CONCLUSIONS: New-onset seizures after aSAH occurred infrequently, and their incidence after aneurysm clipping versus coiling was not significantly different. However, in low-grade patients, new seizures were more frequently associated with clipping than coiling. Additionally, non-convulsive seizures did not occur in low-grade patients treated with coiling. These findings may explain, in part, previous work suggesting better outcomes in coiled patients and encourage physicians to have a lower threshold for cEEG utilization in low-grade patients suspected to have acute seizures after surgical clipping.

Severe Traumatic Brain Injury at a Tertiary Referral Center in Tanzania: Epidemiology and Adherence to Brain Trauma Foundation Guidelines.

BACKGROUND: Severe traumatic brain injury (TBI) is a major cause of death and disability worldwide. Prospective TBI data from sub-Saharan Africa are sparse. This study examines epidemiology and explores management of patients with severe TBI and adherence to Brain Trauma Foundation Guidelines at a tertiary care referral hospital in Tanzania. METHODS: Patients with severe TBI hospitalized at Bugando Medical Centre were recorded in a prospective registry including epidemiologic, clinical, treatment, and outcome data. RESULTS: Between September 2013 and October 2015, 371 patients with TBI were admitted; 33% (115/371) had severe TBI. Mean age was 32.0 years ± 20.1, and most patients were male (80.0%). Vehicular injuries were the most common cause of injury (65.2%). Approximately half of the patients (47.8%) were hospitalized on the day of injury. Computed tomography of the brain was performed in 49.6% of patients, and 58.3% were admitted to the intensive care unit. Continuous arterial blood pressure monitoring and intracranial pressure monitoring were not performed in any patient. Of patients with severe TBI, 38.3% received hyperosmolar therapy, and 35.7% underwent craniotomy. The 2-week mortality was 34.8%. CONCLUSIONS: Mortality of patients with severe TBI at Bugando Medical Centre, Tanzania, is approximately twice that in high-income countries. Intensive care unit care, computed tomography imaging, and continuous arterial blood pressure and intracranial pressure monitoring are underused or unavailable in the tertiary referral hospital setting. Improving outcomes after severe TBI will require concerted investment in prehospital care and improvement in availability of intensive care unit resources, computed tomography, and expertise in multidisciplinary care.

Circumferential cervical surgery: to stage or not to stage?

STUDY DESIGN: Retrospective review. OBJECTIVE: The objective of the study was to determine the morbidity and mortality rate associated with same day versus staged cervical circumferential approach. SUMMARY OF BACKGROUND DATA: A combined approach to the cervical spine is often indicated for complex cervical pathologies. Previous studies suggested superior results associated with same day combined surgery for thoracolumbar patients. This study examines the usefulness of p-Physiological and Operative Severity Score for enumeration of Morbidity and Mortality (POSSUM), an estimated mortality risk assessment for cervical spine patients and will compare same day surgery to staged procedures. METHODS: This is a retrospective chart review including patients who underwent ventral and dorsal approach within 2 weeks. Estimated mortality was calculated using p-POSSUM. The cohort was divided into same day surgery group and staged group. Risk factors were compared between groups. Mean p-POSSUM was calculated and compared with the actual mortality rate. Univariate analysis was used to compare the risk factors between groups and the groups' outcomes. Multivariable analysis was used to adjust for risk factor differences when comparing group outcomes. RESULTS: One hundred thirty-five patients were included, 106 patients were in the same day surgery group whereas 29 patients were in the staged group. Mean p-POSSUM was 2.8% predicted mortality with a 95% confidence interval of 1.6% to 4.1%. The actual mortality rate was 3.7%. The groups did not vary in most risk factors assessed. Univariate analysis demonstrated a statistically significantly higher rate of major complications (0.62 vs. 0.34, P=0.0369), infection (41.4% vs. 9.4%, P<0.0001), and length of hospital stay (9.3 vs. 6.8 d, P=0.0120) in the staged group. Multivariable analysis demonstrated significantly higher infection rate in the staged group. CONCLUSIONS: P-POSSUM mortality estimate may serve as a useful and valid tool for spine surgery studies. Staged combined cervical surgery harbors a higher complication rate and may be associated with lengthier hospitalization.