48-hour video-EEG monitoring for epilepsy presurgical evaluation is cost-effective and safe in resource-limited setting.

INTRODUCTION: Video-EEG monitoring is one of the key investigations in epilepsy pre-surgical evaluation but limited by cost. This study aimed to determine the efficacy and safety of a 48-hour (3-day) video EEG monitoring, with rapid pre-monitoring antiepileptic drugs withdrawal. MATERIAL AND METHODS: This is a retrospective study of epilepsy cases with VEM performed in University Malaya Medical Center (UMMC), Kuala Lumpur, from January 2012 till August 2016. RESULTS: A total of 137 cases were included. The mean age was 34.5 years old (range 15-62) and 76 (55.8 %) were male. On the first 24 -h of recording (D1), 81 cases (59.1 %) had seizure occurrence, and 109 (79.6 %) by day 2 (D2). One-hundred and nine VEMs (79.6 %) were diagnostic, in guiding surgical decision or further investigations. Of these, 21 had less than 2 seizures recorded in the first 48 h but were considered as diagnostic because of concordant interictal ± ictal activities, or a diagnosis such as psychogenic non-epileptic seizure was made. Twenty-eight patients had extension of VEM for another 24-48 h, and 11 developed seizures during the extension period. Extra-temporal lobe epilepsy and seizure frequency were significant predictors for diagnostic 48 -h VEM. Three patients developed complications, including status epilepticus required anaesthetic agents (1), seizure clusters (2) with postictal psychosis or dysphasia, and all recovered subsequently. CONCLUSIONS: 48-h video EEG monitoring is cost-effective in resource limited setting.

Doing More with Less: A Minimally Invasive, Cost-Conscious Approach to Stereoelectroencephalography.

BACKGROUND: Stereoelectroencephalography (SEEG) is a commonly used technique for mapping the epileptogenic zone before epilepsy surgery. Many SEEG depth electrode implantation techniques involve the use of extensive technological equipment and shaving of the patient's entire head before electrode implantation. Our goal was to evaluate an SEEG depth electrode implantation technique that used readily available cost-effective neurosurgical equipment, was minimally invasive in nature, and required negligible hair shaving. METHODS: Data on demographic characteristics, operative time, hemorrhagic complications, implantation complications, infection, morbidity, and mortality among patients who underwent this procedure were reviewed retrospectively. RESULTS: Between April 2016 and March 2018, 23 patients underwent implantation of 213 depth electrodes with use of this technique. Mean (SD) operative time was 123 (32) minutes (range, 66-181 minutes). A mean (SD) of 9.3 (1.4) electrodes were placed for each patient (range, 8-13 electrodes). Two of the 213 electrodes (0.9%) were associated with postimplantation asymptomatic hemorrhage. One of the 213 electrodes (0.5%) was placed extradurally or incorrectly. None of the 213 electrodes was associated with symptomatic complications. No patients experienced infectious complications at any point in the preoperative, perioperative, or postoperative stages. CONCLUSIONS: This minimally invasive, cost-effective technique for SEEG depth electrode implantation is a safe, efficient method that uses readily available basic neurosurgical equipment. This technique may be useful in neurosurgery centers with more limited resources. This study suggests that leaving the patient's hair largely intact throughout the procedure does not pose an additional infection risk.

Yield and cost-effectiveness of tilt table tests combined with video-EEG.

To study the outcomes of a series of consecutive tilt table tests combined with video-EEG (TTVE) at a single center, and assess their cost-effectiveness compared with other neurophysiological tests. We retrospectively reviewed medical records of patients who underwent TTVE studies between March 1st, 2013 to April 1st, 2018. Detailed clinical history, including patient demographics, reasons for referral, anti-seizure medications, and neurophysiological studies obtained prior to the TTVE studies were extracted from chart reviews. The fee for each neurophysiological test was identified from the Centers for Medicare & Medicaid Services. Fifty-two patients underwent TTVE studies. Thirteen patients (25%) were diagnosed with vasovagal syncope, two (3.8%) were diagnosed with postural orthostatic tachycardia syndrome, and three (5.8%) had psychogenic non-epileptic events during the test. Four out of 12 patients stopped anti-seizure medication(s) after the TTVE. Prior to referral for TTVE, an average of $3,748 per person was spent on neurophysiological tests, which were inconclusive. The average fee for one TTVE test was $535.32, and the fee per test affecting diagnosis or management (defined as the cost divided by the yield of the test) was $1,547. The TTVE test is cost-effective in evaluating refractory episodes of loss of consciousness, atypical of epileptic seizures. In addition to diagnosing syncope, TTVE can be valuable in identifying psychogenic events.

Stereoelectroencephalography for Refractory Epileptic Patients Considered for Surgery: Systematic Review, Meta-Analysis, and Economic Evaluation.

BACKGROUND: Stereoelectroencephalography (SEEG) has been shown to be a valuable tool for the anatomoelectroclinical definition of the epileptogenic zone (EZ) in patients with medically refractory epilepsy considered for surgery (RES patients). In Spain, many of those patients are not offered this diagnostic procedure. OBJECTIVE: To evaluate the effectiveness, safety, and cost-effectiveness of SEEG to define the EZ in RES patients compared to no SEEG intervention, ie, remaining with further antiepileptic drugs. METHODS: We undertook a systematic review with meta-analyses on the effectiveness and safety of SEEG. A cost-effectiveness analysis was conducted using a Markov model, which simulates the costs and health outcomes of individuals for a lifetime horizon from the perspective of the Spanish National Health Service. The effectiveness measure was quality-adjusted life years (QALYs). We ran extensive sensitivity analyses, including a probabilistic sensitivity analysis. RESULTS: The EZ was found in 92% of patients who underwent SEEG (95% confidence interval [CI]: 0.87-0.96); 72% were eligible for epilepsy surgery (95% CI: 0.66-0.78) and 33% were free of seizures after surgery (95% CI: 0.27-0.42). Of the patients who underwent surgery, 47% were free of seizures after surgery (95% CI: 0.37-0.58). Complications related to implantation and monitoring of SEEG and the subsequent intervention occurred in 1.3% of patients (95% CI: 0.01-0.02). In the base case analysis, SEEG led to higher QALYs and healthcare costs with an estimated incremental cost-effectiveness ratio of 10 368 EUR per QALY (95% CI: dominant-113 911), making the probability of cost-effectiveness between 75% and 88%. Further sensitivity analyses showed that the results of the study were robust. CONCLUSION: SEEG is a cost-effective technology in RES patients when compared to no SEEG intervention.

Screening for Sturge-Weber syndrome: A state-of-the-art review.

Infants with a high-risk distribution of port-wine stains are commonly screened for Sturge-Weber syndrome using brain magnetic resonance imaging. There is no consensus about which port-wine stain phenotypes to screen, optimal timing, screening sensitivity, or whether presymptomatic diagnosis improves neurodevelopmental outcomes. This state-of-the-art review examines the evidence in favor of screening for Sturge-Weber syndrome, based on its effect on neurodevelopmental outcomes, against the risks and limitations of screening magnetic resonance imaging and electroencephalography. A literature search of PubMed/MEDLINE was conducted between January 2005 and May 2017 using key search terms. Relevant articles published in English were reviewed; 34 articles meeting the search criteria were analyzed according to the following outcome measures: neurodevelopmental outcome benefit of screening, diagnostic yield, financial costs, procedural risks, and limitations of screening magnetic resonance imaging and electroencephalography. There is no evidence that a presymptomatic Sturge-Weber syndrome diagnosis with magnetic resonance imaging results in better neurodevelopmental outcomes. The utility of electroencephalographic screening is also unestablished. In Sturge-Weber syndrome, neurodevelopmental outcomes depend on prompt recognition of neurologic red flags and early seizure control. Small numbers and a lack of prospective randomized controlled trials limit these findings. For infants with port-wine stain involving skin derived from the frontonasal placode (forehead and hemifacial phenotypes), we recommend early referral to a pediatric neurologist for parental education, counselling, and monitoring for neurologic red flags and seizures and consideration of electroencephalography regardless of whether magnetic resonance imaging is performed or its findings.

Cost-Utility of Video-Electroencephalography Monitoring Followed by Surgery in Adults with Drug-Resistant Focal Epilepsy in Thailand.

OBJECTIVES: This study assessed whether video-electroencephalography (VEEG) monitoring followed by surgery was cost-effective in adult patients with drug-resistant focal epilepsy under Thai health care context, as compared with continued medical treatment without VEEG. METHODS: The total cost (in Thai Baht, THB) and effectiveness (in quality-adjusted life years, QALYs) were estimated over a lifetime horizon, using a decision tree and a Markov model. Data on short-term surgical outcomes, direct health care costs, and utilities were collected from Thai patients in a specialized hospital. Long-term outcomes and relative effectiveness of the surgery over medical treatment were derived, using systematic reviews of published literature. RESULTS: Seizure-free rates at years 1 and 2 after surgery were 79.4% and 77.8%, respectively. Costs of VEEG and surgery plus 1-year follow-up care were 216,782 THB, of which the VEEG and other necessary investigations were the main cost drivers (42.8%). On the basis of societal perspective, the total cost over a 40-year horizon accrued to 1,168,679 THB for the VEEG option, 64,939 THB higher than that for no VEEG. The VEEG option contributed to an additional 1.50 QALYs over no VEEG, resulting in an incremental cost-effectiveness ratio of 43,251 THB (USD 1236) per 1 QALY gained. Changes in key parameters had a minimal impact on the incremental cost-effectiveness ratio. Accounting for uncertainty, there was an 84% probability that the VEEG option was cost-effective on the basis of Thailand's cost-effective threshold of 160,000 THB/QALY. CONCLUSIONS: For patients with drug-resistant epilepsy, VEEG monitoring followed by epilepsy surgery was cost-effective in Thailand. Therefore it should be recommended for health insurance coverage.

Discrete classification technique applied to TV advertisements liking recognition system based on low-cost EEG headsets.

BACKGROUND: In this paper a new approach is applied to the area of marketing research. The aim of this paper is to recognize how brain activity responds during the visualization of short video advertisements using discrete classification techniques. By means of low cost electroencephalography devices (EEG), the activation level of some brain regions have been studied while the ads are shown to users. We may wonder about how useful is the use of neuroscience knowledge in marketing, or what could provide neuroscience to marketing sector, or why this approach can improve the accuracy and the final user acceptance compared to other works. METHODS: By using discrete techniques over EEG frequency bands of a generated dataset, C4.5, ANN and the new recognition system based on Ameva, a discretization algorithm, is applied to obtain the score given by subjects to each TV ad. RESULTS: The proposed technique allows to reach more than 75 % of accuracy, which is an excellent result taking into account the typology of EEG sensors used in this work. Furthermore, the time consumption of the algorithm proposed is reduced up to 30 % compared to other techniques presented in this paper. CONCLUSIONS: This bring about a battery lifetime improvement on the devices where the algorithm is running, extending the experience in the ubiquitous context where the new approach has been tested.

How long is long enough? The utility of prolonged inpatient video EEG monitoring.

Video EEG monitoring (VEM) is a valuable tool for the diagnosis of epileptic seizures (ES) and psychogenic nonepileptic seizures (PNES). We sought to determine the benefits of prolonged length of stay (LOS). We retrospectively reviewed the records of patients admitted for VEM. We analyzed LOS for ES and PNES patients to determine if there was reduced utility, as evidenced by a significantly higher inconclusive outcome, beyond a certain duration. We calculated receiver operating characteristic (ROC) curves to determine optimal cut off points for LOS based on futility. Patients admitted with presumed PNES were significantly more likely to have an inconclusive admission (31/150, 20.7%) versus all others (58/446, 13%, p=0.033). There was no significant difference in the likelihood of having an inconclusive admission if monitoring was continued for any duration in patients with ES (area under curve, AUC, 0.46). For patients with PNES, a LOS ≥5 days was associated with an increased risk of the stay being inconclusive (28% versus 12.5%, p=0.026). Although the ROC curve suggested a cut off of 5.5 days, it did not predict outcomes well (AUC 0.52, sensitivity 0.55, specificity 0.5). Based on our data, prolonging VEM appears useful for the proper classification and localization of ES.

A critical appraisal on the utility of long-term video-EEG monitoring in older adults.

BACKGROUND: World-over, the majority of patients undergoing video-EEG monitoring (VEM) are in their second or third decades. Although elderly represent the fastest growing segment of population with epilepsy, only few of them undergo VEM. We critically evaluated the utility of VEM in the diagnosis and long-term management of older adults with paroxysmal behavioral events. METHODS: 148 consecutive patients aged 45 and above, who underwent long-term (≥8 h) inpatient VEM from 1996 to 2009 formed the study cohort. Utilizing a structured proforma, we gathered their demographic, clinical, electrophysiological and long-term outcome data. VEM was considered as "useful" when it changed the diagnosis and/or management; it was "corroborative" when it helped the treating physician to confirm the diagnosis and "not useful" when it neither helped to improve the diagnosis nor the management. RESULTS: The mean age was 51.3 (SD 6.4) years; mean duration of VEM was 69.3 h. Out of 117 patients with a diagnosis of epileptic seizures referred for presurgical evaluation or classification, VEM was "useful" or "corroborative" in 111 patients (94.8%; p=0.0001). It was also "useful" or "corroborative" in 29 out of 31 patients (93.5%) referred with a suspicion of associated or pure psychogenic non-epileptic seizures (p=0.0001). None developed any complications during monitoring. At a mean follow-up of 37.7 months there was significant reduction in AED usage in patients with epilepsy (p=0.0001) and epilepsy with associated PNES (p=0.001). At a mean follow-up of 34.2 months, all patients with pure PNES were event-free and medication-free at last follow-up (p=0.002). Twenty-three patients (19.6%) underwent surgery, all except one remaining seizure-free at a mean follow-up of 39.2 months. CONCLUSIONS: VEM is a safe and cost-effective investigation strategy in older-adults. It aided in improving the diagnosis, offered better treatment including surgery and helped in excluding non-epileptic paroxysmal events in majority.

How to effectively constrain the cost of presurgical evaluation for resective surgery in low-income population: clinically oriented opinions.

Epilepsy surgery plays a pivotal role in the successful treatments of intractable epilepsy. In China, economic burden for epileptic patients is heavy. Because of limited economic resources, appropriate utilization of presurgical evaluation technologies is especially important for low-income patients, who could benefit from surgery. This study proposed the strategies for restricting the cost of presurgical evaluation for resective surgery in low-income population with refractory epilepsy. A retrospective study was performed on the database of patients with resective surgery from January 2007 to June 2009 in West China Hospital of Sichuan University. Presurgical evaluation technologies and outcome were analyzed. As a result, 143 patients underwent resective operation were included in this study. Seizure free can be reached at 63.8% patients with (ATL) and 61.1% with focal lesionectomy (FLE). Magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), positron emission tomography (PET), routine electroencephalography (REEG), video-EEG (VEEG) and invasive-EEG (IEEG) were used for investigation. The cost of those technologies was listed for consultation. Based on these findings, how to make the proper choice for surgery candidates was suggested according to different types of epilepsy.

Significance and cost-effectiveness of somatosensory evoked potential monitoring in cervical spine surgery.

BACKGROUND: Intraoperative somatosensory evoked potential (SSEP) monitoring during cervical spine surgery is not a universally accepted standard of care. Our retrospective study evaluated the efficacy and cost-effectiveness of intraoperative SSEP in a single surgeon's practice. MATERIALS AND METHODS: Intraoperative SSEP monitoring was performed on 210 consecutive patients who had cervical spine surgery: anterior cervical approach 140 and posterior approach 70. They were screened for degradation or loss of SSEP data. A cost analysis included annual medical costs for health and human services, durable goods and expendable commodities. RESULTS: Temporary loss of the electrical wave during cauterization resolved upon discontinuation of the cautery. We had no loss of cortical wave with preservation of the popliteal potential. A drop in the amplitude of the cortical wave was observed in three patients. This drop was resolved after hemodynamic stabilization in the first patient, readjusting the bone graft in the second patient, and interrupting the surgery in the third patient. The additional cost for SSEP monitoring was $835 per case and the total cost of the surgery was $13,835 per case. By spending $31,546 per year on SSEP, our institution is saving a total cost ranging from $64,074 to $102,192 per patient injured per year. CONCLUSION: Intraoperative SSEP monitoring is a reliable and cost-effective method for preventing postoperative neurological deficit by the early detection of vascular or mechanical compromise, and the immediate alteration of the anesthetic or surgical technique.

A prospective study on the cost-effective utilization of long-term inpatient video-EEG monitoring in a developing country.

To investigate diagnostic value, therapeutic benefit and cost-effective utilization of video-EEG monitoring (VEM) in a comprehensive epilepsy program in a developing country. The authors prospectively recruited all patients who underwent long-term (> or =3 hours) inpatient VEM during a 10-month period. The cohort was followed to gather information about the proportion of patients in whom long-term management was altered by VEM and resultant impact on direct health care costs. Out of 143 study subjects (median age 22 years), 102 (71.3%) were referred for presurgical evaluation. The median duration of VEM was 61 hours, and median number of events recorded per patient was 3. Video-EEG monitoring helped to clarify the epilepsy syndromic diagnosis in 123 of 132 (93.2%) patients referred with the diagnosis of epileptic seizures. Video-EEG monitoring confirmed coexistent complex partial seizures in 4 of 11 (36.4%) patients with a referral diagnosis of psychogenic nonepileptic events. During mean follow-up period of 2.2 years, 48 patients (33.6%) underwent epilepsy surgery. A significant decrease in antiepileptic drug polytherapy, and minimization in recurring direct medical and nonmedical costs occurred. In addition to immediate diagnostic usefulness, VEM contributes significantly to long-term therapeutic and economic benefits for patients with difficult to diagnose and treat paroxysmal events.

Use of conventional ECG electrodes for depth of anaesthesia monitoring using the cerebral state index: a clinical study in day surgery.

BACKGROUND: The cost-benefit relationship for depth of anaesthesia monitors is complicated by the high cost of specially designed EEG electrodes. The cerebral state index (CSI) monitor will accept regular ECG electrodes with snap connectors. The purpose of this study was to determine if generic ECG electrodes could replace the more expensive proprietary EEG electrodes for the CSI monitor. METHODS: Two identical cerebral state monitors were used simultaneously during sevoflurane anaesthesia for knee arthroscopy in 14 ASA I-II patients. One monitor used proprietary (Danmeter) EEG electrodes and the other used ECG electrodes (3M Red Dot Diagnostic ECG Electrodes). Paired CSI values were recorded every other minute. Anaesthetic depth was titrated clinically. Sedation depth was scored according to the Observer's Assessment of Alertness/Sedation (OAAS) scale. RESULTS: The agreement between the two measures was found to be high, mean difference--0.23, and the overall repeatability mean bias was 6.6 and 153/163 pairs (94%) were located within the 95% limits of agreement. No major difference was noted in impedance, noise, or artifacts. A large overlap in CSI was noted for each level of the OAAS scale; patients with CSI values as low as 40-50 responded whereas patients not responding to surgical stimulation had CSI values as high as 75. The direct cost of disposables decreased from 4euro to 0.50euro per patient by using ordinary ECG electrodes. CONCLUSIONS: Switching from proprietary EEG electrodes to ordinary generic ECG electrodes maintains the same accuracy at about a 10th of the cost when measuring CSI during day surgery with sevoflurane anaesthesia.

Correlation of carotid artery stump pressure and neurologic changes during 474 carotid endarterectomies performed in awake patients.

PURPOSE: A carotid artery stump pressure (SP) of < 50 mm Hg and abnormal electroencephalography (EEG) changes have been suggested as indications for selective shunting in patients undergoing carotid endarterectomy (CEA) under general anesthesia. We attempted to determine the optimal SP threshold that correlated with neurologic changes in awake patients undergoing CEA using cervical block anesthesia (CBA) and performed a cost comparison with EEG monitoring. METHODS: Between July 1, 1995, and December 31, 2004, SP was measured during 474 CEAs performed under CBA by inserting a 19-gauge butterfly needle into the common carotid artery. A saline-filled intravenous bag in the patient's contralateral hand was connected to pressure tubing to generate waveforms with hand squeezing that could be visualized on a monitor. Systemic pressure was maintained approximately 10 mm Hg higher than baseline. Accurate SPs were confirmed by the finding of flatline waveforms after internal carotid artery clamping. Selective shunting was performed when neurologic changes occurred (aphasia, inability to squeeze the contralateral hand, decreased consciousness), regardless of SP. During this same period, 142 patients underwent CEA using GA, and SP was also measured. RESULTS: Shunting was necessary because of neurologic changes in 7.2% (34/474) of all CEAs performed using CBA: 0.9% (3/335) with SPs > or = 50 mm Hg systolic vs 1.0% (4/402) with SPs > or = 40 mm Hg systolic, and 22% (31/139) with SPs < 50 mm Hg systolic vs 42% (30/72) with SPs < 40 mm Hg systolic. If these 474 CEAs had been performed using GA, shunts would have been used in 29% (139/474) of patients for a SP < 50 mm Hg systolic vs 15% (72/474) for a SP < 40 mm Hg systolic. In patients not shunted, the perioperative stroke/death rate was 1.2% in patients (4/332) with SPs > or = 50 mm Hg vs 1.0% (4/398) with SPs > or = 40 mm Hg. Three of the four strokes occurred > 24 hours postoperatively and were unrelated to lack of shunting and ischemia. There was no significant difference in the percentage of patients with SPs > or = 50 mm Hg who underwent CEA using CBA (70%, 335/474) vs GA (67%, 96/142) during this time period. At our hospital, charges for SPe measurement, including anesthesia charges and tubing, were 229 dollars per case vs 3439 dollars per case for EEG monitoring. Use of SP measurements in these 474 patients would have resulted in reduced charges of 1,521,540 dollars compared with EEG monitoring if CEA had been performed under GA. CONCLUSION: Using 40 mm Hg systolic as a threshold, the need for shunting (15%) and the false-negative rate (1.0%) for SP in our series were equivalent to the results of EEG monitoring during CEA reported in the literature. However, charges for SP measurements are dramatically lower compared with EEG monitoring. Our results suggest that a carotid artery SP > or = 40 mm Hg systolic may be considered as an equally reliable but more cost-effective method to predict the need for carotid shunting during CEA under GA compared with EEG monitoring, but further investigation is warranted.

Is the patient state analyzer with the PSArray2 a cost-effective alternative to the bispectral index monitor during the perioperative period?

New disposable electrodes, the PSArray and XP sensor, have been developed for the patient state analyzer (PSA) and the bispectral index (BIS) monitors, respectively. We designed this clinical study to compare the sensitivity and specificity of the patient state index (PSI) with the BIS during the perioperative period when the new electrode sensors were used. Twenty-two consenting patients scheduled for elective laparoscopic procedures were enrolled in this prospective study. The elapsed time to apply electrodes and obtain a baseline index value was recorded, as were the comparative PSI and BIS values at specific time intervals during the induction, maintenance, and emergence periods in patients who were administered a standardized general anesthetic. In addition, the changes in these indices were recorded after a bolus dose of propofol (20 mg IV) or a 2% increase or decrease in the inspired concentration of desflurane during the maintenance period. The total elapsed time to obtain an index value was similar with both devices (66 +/- 32 s versus 72 +/- 41 s for the PSA and BIS, respectively). By using logistic regression models, both the BIS and PSI were found to be equally effective as predictors of unconsciousness (i.e., failure to respond to verbal stimuli). The PSI also correlated with the BIS during both the induction of (R = 0.85) and the emergence from (R = 0.74) general anesthesia. The area under the receiver operating characteristic curve for detection of consciousness also indicated a similar performance with the PSI (0.98 +/- 0.05) and the BIS (0.97 +/- 0.05). During the maintenance period, the PSI values tended to be lower than the BIS value; however, the responses to changes in propofol and desflurane were similar. Finally, the PSI (versus BIS) values showed less interference from the electrocautery unit during the operation (31% versus 73%, respectively). Although the list price of the PSArray(2) disposable electrode strip (USD $24.95) was higher than that of the BIS XP sensor (USD $17.50), the average sale price (USD $14.95) was identical for both electrode systems. Therefore, we conclude that the PSA monitor with the PSArray(2) is a cost-effective alternative to the BIS monitor with the XP sensor for evaluating consciousness during the induction of and emergence from general anesthesia, as well as for titrating propofol and desflurane during the maintenance period.

Effects of Bispectral Index monitoring on ambulatory anesthesia: a meta-analysis of randomized controlled trials and a cost analysis.

BACKGROUND: Ambulatory surgery is growing in popularity worldwide. For example, 50-70% of surgical procedures in North America are performed on an ambulatory basis. Use of Bispectral Index (BIS) monitoring for titration of general anesthesia may allow use of less anesthetics, reduction in side effects, and faster patient recovery. METHODS: MEDLINE and other databases were searched for randomized controlled trials examining the use of BIS monitoring versus standard practice in ambulatory surgery patients. Outcomes were extracted from these articles, and a meta-analysis was performed. RESULTS: One thousand three hundred eighty subjects from 11 trials were included in the meta-analysis. The use of BIS monitoring significantly reduced anesthetic consumption by 19%, reduced the incidence of nausea/vomiting (32% vs. 38%; odds ratio, 0.77), and reduced time in the recovery room by 4 min. However, these benefits did not result in significant reduction in time until patient discharge from the ambulatory surgery unit. Cost analysis using pooled costs to reflect North America, Europe, and Asia indicated that use of BIS monitoring increased the cost per patient by 5.55 US dollars because of the cost of BIS electrodes. CONCLUSIONS: The use of BIS monitoring modestly reduced anesthetic consumption, risk of nausea and vomiting, and recovery room time. These benefits did not reduce time spent in the ambulatory surgery unit, and cost of the BIS electrode exceeded any cost savings.

Bispectral index-guided anesthesia in patients undergoing aortocoronary bypass grafting.

In this prospective, randomized study, we compared hemodynamics, oxygenation, possible intraoperative awareness, and costs in 62 patients undergoing first-time elective coronary artery bypass grafting at 2 different levels of anesthesia. Depth of anesthesia was assessed with bispectral index (BIS). All patients were anesthetized with sufentanil/midazolam. The dosage of sufentanil/midazolam was adjusted to achieve a BIS level of 45-55 in 32 patients (Group BIS 50), whereas in 30 patients a BIS level of 35-45 was intended (Group BIS 40). Data were obtained at six different time points before, during, and after surgery. All patients were asked about possible intraoperative awareness on the third postoperative day. There were no significant differences of any hemodynamic or oxygenation variables at any time between the two groups. BIS 40 patients received significantly (P < 0.05) more sufentanil (BIS 40, 888 +/- 211 microg; BIS 50, 514 +/- 99 microg) and midazolam (BIS 40, 22.4 +/- 5.6 mg; BIS 50, 16.6 +/- 3.7 mg) than BIS 50 patients. The reduction in anesthetic drugs used saved euro;13.78/US$12.54 per patient (P < 0.05) in Group BIS 50, but one BIS electrode caused additional costs of 19.95 Euros/18.15 US dollars. Time to extubation was not significantly prolonged in Group BIS 40 (BIS 40, 14.3 +/- 4.6 h; BIS 50, 11.8 +/- 3.8 h). There was no explicit memory during anesthesia in either group. BIS-guided reduction of anesthetic medication saved costs and did not increase the risk of intraoperative awareness. However, total costs were increased by monitoring BIS, because of the BIS electrodes.

Assessment and cost comparison of sleep-deprived EEG, MRI and PET in the prediction of surgical treatment for epilepsy.

Our aim was to determine if less expensive interictal indices can predict which epilepsy patients may benefit from the more expensive comprehensive pre-surgical evaluation. Surgical treatment was determined based on the results of a comprehensive inpatient continuous video-EEG monitoring. This evaluation included three interictal tests, which were reviewed retrospectively-2 hour-sleep-deprived electroencephalogram (SDEEG), magnetic resonance imaging (MRI), and positron emission tomography (PET). Sixty-nine patients were evaluated with 35 patients having focal resection (33 temporal, two frontal). When two or more interictal tests were positive, 77% (27 /35) went to surgery, but when one test was positive 23% (8 /34) had surgery. When all tests were negative, only a single patient (1 /13 or 7.7%) had surgery, a frontal resection. The positive predictive value for any single interictal test was 68%, while it was higher for any combination of two positive tests (77-83%). PET was the most sensitive (0.86) single interictal test, compared to SDEEG (0.66) and MRI (0.66). The odds ratio for predicting surgical treatment for a positive PET, SDEEG, or MRI was 8.57, 4.01, and 4.01, respectively. MRI was three and PET was six times the cost of a SDEEG. The combination of SDEEG and MRI had the best cost/PPV ratio. Seventy-nine percent (11 /14) of the patients with three positive tests were seizure free following focal resection compared to 43% (9 /21) when less than three tests were positive ( P

Simple, cost-effective technique for portable digital eletrocorticography.

We revised 16 patients submitted to epilepsy surgery using a new method of digital, real-time, portable electrocorticography. Patients were operated upon over a period of 28 months. There were no complications. The exam was useful in 13 cases. The low installation and operational costs, the reliability and simplicity of the method, indicate it may be useful for defining the epileptogenic regions in a variety of circumstances, including surgery for tumors, vascular malformations, and other cortical lesions associated with seizure disorders.

EEG bispectral index monitoring in sevoflurane or propofol anaesthesia: analysis of direct costs and immediate recovery.

BACKGROUND: Recent studies have suggested that electroencephalogram (EEG) bispectral index (BIS) monitoring can improve recovery after anaesthesia and save money by shortening patients' postoperative stay. We wanted to evaluate the direct costs of BIS monitoring and to measure immediate recovery after anaesthesia in patients with or without BIS monitoring. METHODS: Eighty patients undergoing gynaecological surgery were studied. At first, 40 patients were randomized to receive either propofol or sevoflurane anaesthesia. In these patients, BIS was collected but the information was not displayed. Thereafter, the anaesthesiologists were trained to follow and understand the BIS information, and 40 patients were anaesthetized with aid of the monitoring. Recovery times were measured by a study coordinator. Drug consumption was calculated. RESULTS: BIS monitoring improved the immediate recovery after propofol anaesthesia, while no differences were seen in patients receiving sevoflurane. The consumption of both propofol and sevoflurane decreased significantly (29% and 40%, respectively). BIS monitoring increased direct costs in these patients; the break-even times (704 min for propofol and 282 min for sevoflurane) were not reached. CONCLUSION: BIS monitoring decreased the consumption of both propofol and sevoflurane and hastened the immediate recovery after propofol anaesthesia. Detailed cost analysis showed that the monitoring increased direct costs of anaesthesia treatment in these patients, mainly due to the price of special EEG electrodes used for relatively short anaesthesias.