Quantitative electroencephalography characteristics of tilt-induced neurally-mediated syncope among youth.

OBJECTIVE: To characterize the quantitative electroencephalographic (QEEG) patterns associated with tilt-induced syncope in youth. METHODS: Several QEEG parameters were analyzed. Data were calculated for peak or nadir changes with syncope for amplitude-EEG, fast Fourier transform (FFT) power in several frequency ranges, 8-13 Hz/1-4 Hz frequency ratio, and FFT edge. RESULTS: Changes in QEEG parameters were present among all patients with tilt-induced syncope (n = 76). These changes included increases in the low frequency FFT power (1-4 Hz range), decreases in the power ratio (8-13 Hz/1-4 Hz) and decreases in the FFT edge (95%, 1-18 Hz). All patients had suppression of EEG amplitudes that closely followed loss of consciousness. Asymmetry indices demonstrated cerebral hemisphere lateralization at multiple periods during the evolution of syncope, but the side of lateralization did not differ from 0.5 probability. CONCLUSIONS: QEEG parameters can be used to characterize EEG changes associated with tilt-induced, neurally-mediated syncope. SIGNIFICANCE: QEEG may serve as a useful tool for the study of syncope neurophysiology, and the modeling of changes with syncope may improve our understanding of other neurologic disorders caused by defects in cerebral perfusion.

Diagnosis of Electrical Status Epilepticus During Slow-Wave Sleep With 100 Seconds of Sleep.

PURPOSE: Strategies for diagnosing electrical status epilepticus during slow-wave sleep (ESES) vary among interpreting neurologists. Our aim was to evaluate if the spike-wave index (SWI) for the first 100 seconds of sleep is reflective of the SWI when compared with a conventional method. METHODS: We reviewed EEGs from 2005 to 2011 that were considered diagnostic of ESES based on unspecified methods. The SWI for the first nonrapid eye movement sleep cycle (long method) was calculated by two neurophysiologists. Two different neurophysiologists calculated SWI for the first 100 seconds of sleep (short method). For the purposes of this study, ESES was defined as an SWI of >85%. The two SWI scores were compared. RESULTS: Fourteen EEGs were reviewed. Despite being considered by the initial interpreter as diagnostic of ESES, only 4 of the studies had an SWI of >85% based on each of the methods. For a diagnosis of ESES, the sensitivity of the short method is 80% and the specificity is 89%. Wilcoxon signed rank test was used to compare the long and short methods. A P value of 0.70 indicates no significant difference between the methods. Additionally, the Spearman correlation coefficient is 0.553 (P = 0.04), indicating moderate correlation between the methods. CONCLUSIONS: The SWI for the first 100 seconds of nonrapid eye movement sleep is predictive of the SWI for the entire first sleep cycle with a good sensitivity and specificity in our cohort. This suggests an alternative method for diagnosing ESES, which is comparable to analysis of a full night of sleep.

Prehospital rapid-sequence intubation: a pilot training program.

OBJECTIVE: To develop a training program enabling paramedics to use sedation and paralytic medications to facilitate endotracheal intubation in patients who otherwise could not be successfully intubated. METHODS: Paramedics underwent a training program consisting of six hours of didactic education, two four-hour mannequin labs, one four-hour animal intubation lab, and operating room experience. Rapid-sequence intubation (RSI) runs were reviewed for appropriateness in patient selection and medication use. Non-RSI runs were reviewed to determine whether appropriate patients were being missed. Intubation success rates continue to be followed. Long-term quality assurance includes monthly run reviews, periodic quizzes, and unannounced on-site practical tests. RESULTS: 101 patients have been intubated using RSI, including medical, trauma, pediatric, and adult cases. Of all patients receiving RSI drugs, 100 of 101 were successfully intubated. There were no undetected esophageal intubations. Paramedics were able to demonstrate proper patient selection and appropriately administer RSI medications. The use of sheep labs was a critical component of this training because it permitted multiple intubations in a live model possessing an airway quite similar to that of the human. The gum elastic bougie was felt to be critical in the intubation of three patients. CONCLUSION: This RSI training model can serve as a template for other agencies seeking to implement RSI. Limitations of this model include the availability of live animal labs and the expense of conducting the training. Intense medical director involvement has been key to the success of this prehospital RSI program.