Correlation Between Processed Electroencephalogram and Clinical Findings During Wake-Up Test in Prone Position for Scheduled Posterior Cervical Spine Surgery: A Case Report.

A 65-year-old man undergoing posterior cervical decompression and fusion demonstrated absent lower extremity evoked potential (EP) after prone positioning and before incision. Localized EP change pointed to either a technical or positional culprit. After excluding technical causes, we performed a wake-up test to rule out positioning as the culprit. During the test, we observed both symmetrical and asymmetrical hemispheric changes in density spectral array ß and γ bands that correlated with awakening, eye-opening, and extremity movements. By providing real-time information on brain state, processed electroencephalogram (EEG) can facilitate a safe wake-up test by showing high-power ß and γ activities that precede awakening.

Cost-effectiveness of elective laparoscopic cholecystectomy versus observation in older patients presenting with mild biliary disease.

Our objective was to determine the probability threshold for recurrent symptoms at which elective cholecystectomy compared to observation in older patients with symptomatic cholelithiasis is the more effective and cost-effective option. We built a decision model of elective cholecystectomy versus observation in patients >65 presenting with initial episodes of symptomatic cholelithiasis that did not require initial hospitalization or cholecystectomy. Probabilities for subsequent hospitalization, emergency cholecystectomy, and perioperative complications were based on previously published probabilities from a 5 % national sample of Medicare patients. Costs were estimated from Medicare reimbursements and from the Healthcare Cost and Utilization Project. Utilities (quality-adjusted life years, QALYs) were obtained from established literature estimates. Elective cholecystectomy compared to observation in all patients was associated with lower effectiveness (-0.10 QALYs) and had an increased cost of $3,422.83 per patient at 2-year follow-up. Elective cholecystectomy became the more effective option when the likelihood for continued symptoms exceeded 45.3 %. Elective cholecystectomy was both more effective and less costly when the probability for continued symptoms exceeded 82.7 %. An individualized shared decision-making strategy based on these data can increase elective cholecystectomy rates in patients at high risk for recurrent symptoms and minimize unnecessary cholecystectomy for patients unlikely to benefit.