Effects of remimazolam combined with remifentanil on quality of recovery after ambulatory hysteroscopic surgery: a prospective, observational study

Background@#Remimazolam, a new benzodiazepine, is known for its quick onset of effects and recovery time. Recently, it has been licensed for general anesthesia and sedation in Korea and its use is increasing in other countries. However, less is known about its effect on postoperative recovery. We used a patient-reported outcome questionnaire to examine the effect of remimazolam on postoperative recovery. @*Methods@#Patients who underwent hysteroscopy on day surgery basis were administered an induction dose of remimazolam 6 mg/kg/h followed by a maintenance dose of 1–2 mg/kg/h. After surgery, the translated Korean version of 15-item Quality of Recovery scale (QoR-15K) including post-discharge nausea and vomiting (PDNV) and/or pain, was surveyed 24 h after surgery to evaluate patient recovery. @*Results@#Total of 38 patients were enrolled in this prospective, observational study. All patients successfully completed QoR-15K. Only one patient scored low for moderate pain and PDNV. On average, patients scored 9 and above for all QoR-15K items except for moderate pain (8.66 ± 1.68). When QoR-15K items were grouped into dimensions, all dimensions scored an average of 9 or higher on a 10-point scale. In addition, 19 out of 38 patients gave score range of 148 to 150 out of possible 150. @*Conclusions@#Psychometric evaluation based on postoperative QoR-15K among patients receiving remimazolam shows satisfactory patient recovery profiles without significant pain or PDNV. Considering its effectiveness and safety, remimazolam could be one of useful agents for general anesthesia of day surgery in terms of postoperative recovery.

Underutilisation of Physical Rehabilitation Therapy by Cancer Patients in Korea: a Population-based Study of 958,928 Korean Cancer Patients

Background@#Advanced cancers are associated with more severe symptoms and greater impairment. Although most patients with metastatic cancer would benefit from rehabilitation, few patients receive appropriate rehabilitation therapy. We explored the use of rehabilitation therapy by cancer patients. Our data represented the entire population of Korea. The analyses were performed according to cancer type and stage. @*Methods@#We extracted rehabilitation utilization data of patients newly diagnosed with cancer in the period of 2011–2015 from the Korea Central Cancer Registry, which is linked to the claims database of the National Health Insurance Service (n = 958,928). @*Results@#The utilisation rate increased during the study period, from 6.0% (11,504) of 192,835 newly diagnosed patients in 2011 to 6.8% (12,455) of 183,084 newly diagnosed patients in 2015. Patients with central nervous system (28.4%) and bone (27.8%) cancer were most likely to undergo physical rehabilitation. The rehabilitation rate was higher in patients with metastatic than localised or regional cancer (8.7% vs. 5.3% vs. 5.5%). @*Conclusion@#This claims-based study revealed that rehabilitation therapy for cancer patients is underutilised in Korea. Although patients with metastasis underwent more intensive rehabilitation than patients with early stage cancer, those without brain and bone tumours (the treatment of which is covered by insurance) were less likely to use rehabilitation services. Further efforts to improve the use of rehabilitation would improve the outcomes of cancer patients.

Supervised Physical Rehabilitation in the Treatment of Patients with Advanced Cancer: a Systematic Review and Meta-analysis

Background@#As the survival rate of cancer patients increases, the clinical importance of rehabilitation provided by healthcare professionals also increases. However, the evidence supporting the relevance of rehabilitation programs is insufficient. This study aimed to review the literature on effectiveness in physical function, quality of life (QOL) or fatigue of supervised physical rehabilitation in patients with advanced cancer. @*Methods@#A systematic review and meta-analysis was conducted following the Cochrane guidelines. We narratively described the results when meta-analysis was not applicable or appropriate. Literature databases including Ovid-MEDLINE, Ovid-EMBASE, and the Cochrane Library, as well as several Korean domestic databases, were searched up to June 2017 for studies that investigated the effectiveness of supervised physical rehabilitation programs on physical function, QOL or fatigue in patients with advanced cancer. The quality of the selected studies was evaluated independently by paired reviewers. @*Results@#Eleven studies with 922 participants were finally selected among 2,459 articles. The meta-analysis revealed that after physical exercise, the physical activity level and strength of patients with advanced cancer increased significantly. The QOL showed a statistically significant improvement after physical rehabilitation according to the European Organization for Research and Treatment of Cancer version C30. Though some of measurements about cardiovascular endurance or strength in several studies were not able to be synthesized, each study reported that they were significantly improved after receiving rehabilitation. @*Conclusion@#Supervised physical rehabilitation for patients with advanced cancer is effective in improving physical activity, strength, and QOL. However, more trials are needed to prove the effectiveness of supervised exercise and to strengthen the evidence.

Development of the short version of the Gynecologic Cancer Lymphedema Questionnaire: GCLQ-7 / 부인종양

OBJECTIVE: The Gynecologic Cancer Lymphedema Questionnaire (GCLQ) was designed to identify gynecologic cancer patients with lower limb lymphedema (LLL). The questionnaire consists of 20 items distributed over 7 symptom clusters. The present study aimed to develop an abridged form of the GCLQ for simpler screening and more effective follow-up of LLL. METHODS: Data that had been collected for the development and validation of the Korean version of the GCLQ (GCLQ-K) were used in this study. Receiver-operating characteristic (ROC) curves were drawn according to the individual items of the GCLQ-K. Based on discrimination ability, the candidate items were selected in each symptom cluster. After combining the items, the best model was identified and named GCLQ-7. The area under the ROC curve (AUC) was compared between the GCLQ-7 and the original GCLQ-K. RESULTS: In total, 11 candidate items were selected from the original GCLQ-K. Among the models made with the candidate items, GCLQ-7, the best model, was constructed with 7 items as follows: 1) limited knee movement, 2) general swelling, 3) redness, 4) firmness/tightness, 5) groin swelling, 6) heaviness, and 7) aching. This model exhibited an AUC of 0.945 (95% confidence interval [CI], 0.900–0.991), which is comparable with that of the original GCLQ-K (AUC, 0.867; 95% CI, 0.779–0.956). The best cutoff value was 2 points, at which the sensitivity and specificity were 97.0% and 76.5%, respectively. CONCLUSION: The newly developed short version model, GCLQ-7, showed acceptable discrimination ability as compared with the original GCLQ-K.

Computed tomography-based quantitative assessment of lower extremity lymphedema following treatment for gynecologic cancer / 부인종양

OBJECTIVE: To develop an algorithmic quantitative skin and subcutaneous tissue volume measurement protocol for lower extremity lymphedema (LEL) patients using computed tomography (CT), to verify the usefulness of the measurement techniques in LEL patients, and to observe the structural characteristics of subcutaneous tissue according to the progression of LEL in gynecologic cancer. METHODS: A program for algorithmic quantitative analysis of lower extremity CT scans has been developed to measure the skin and subcutaneous volume, muscle compartment volume, and the extent of the peculiar trabecular area with a honeycombed pattern. The CT venographies of 50 lower extremities from 25 subjects were reviewed in two groups (acute and chronic lymphedema). RESULTS: A significant increase in the total volume, subcutaneous volume, and extent of peculiar trabecular area with a honeycombed pattern except quantitative muscle volume was identified in the more-affected limb. The correlation of CT-based total volume and subcutaneous volume measurements with volumetry measurement was strong (correlation coefficient: 0.747 and 0.749, respectively). The larger extent of peculiar trabecular area with a honeycombed pattern in the subcutaneous tissue was identified in the more-affected limb of chronic lymphedema group. CONCLUSION: CT-based quantitative assessments could provide objective volume measurements and information about the structural characteristics of subcutaneous tissue in women with LEL following treatment for gynecologic cancer.

A Case of Auditory Neuropathy Caused by Pontine Hemorrhage in an Adult

A pontine hemorrhage can evoke several neurological symptoms because the pons contains various nuclei and nerve fibers. Hearing loss can develop as a result of a pontine hemorrhage because there is an auditory conduction pathway in the cochlear nucleus of the pons. However, very few cases of hearing loss caused by pontine lesions have been reported, and there have been no reports of auditory neuropathy that developed following a pontine hemorrhage. Recently we had a patient who experienced a nontraumatic pontine hemorrhage who was diagnosed with auditory neuropathy. The 34-year-old male patient was admitted to the emergency department with sudden alteration of mental status. His brain computed tomographic imaging revealed a hemorrhage in the central pons. He complained of hearing difficulties after his mental status recovered through conservative treatment, but a pure-tone audiogram showed very mild hearing loss in both ears. Further hearing tests using otoacoustic emissions, which showed normal responses, and auditory brainstem responses, which showed no waveforms at maximum stimulus intensity, revealed that his hearing difficulties were caused by auditory neuropathy. This case implies that the threshold of sound detection can be preserved in patients with pontine hemorrhage who complain of hearing difficulties. Auditory neuropathy should be considered as a possible cause of hearing difficulties in these patients and appropriate hearing tests should be performed.

Identification of Prognostic Risk Factors for Transient and Persistent Lymphedema after Multimodal Treatment for Breast Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study is to identify risk factors for transient lymphedema (TLE) and persistent lymphedema (PLE) following treatment for breast cancer. MATERIALS AND METHODS: A total of 1,073 patients who underwent curative breast surgery were analyzed. TLE was defined as one episode of arm swelling that had resolved spontaneously by the next follow-up; arm swelling that persisted over two consecutive examinations was considered PLE. RESULTS: At a median follow-up period of 5.1 years, 370 cases of lymphedema were reported, including 120 TLE (11.2%) and 250 PLE (23.3%). Initial grade 1 swelling was observed in 351 patients, of which 120 were limited to TLE (34%), while the other 231 progressed to PLE (66%). All initial swelling observed in TLE patients was classified as grade 1. In multivariate analysis, chemotherapy with taxane and supraclavicular radiation therapy (SCRT) were associated with development of TLE, whereas SCRT, stage III cancer and chemotherapy with taxane were identified as risk factors for PLE (p < 0.05). The estimated incidence of TLE among initial grade 1 patients was calculated using up to three treatment-related risk factors (number of dissected axillary lymph nodes, SCRT, and taxane chemotherapy). The approximate ratios of TLE and PLE based on the number of risk factors were 7:1 (no factor), 1:1 (one factor), 1:2 (two factors), and 1:3 (three factors). CONCLUSION: One-third of initial swelling events were transient, whereas the other two-thirds of patients experienced PLE. Estimation of TLE and PLE based on known treatment factors could facilitate prediction of this life-long complication.

Current Practice and Barriers in Cancer Rehabilitation: Perspectives of Korean Physiatrists / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study was to assess clinical practice and barriers associated with cancer rehabilitation from the perspective of Korean physiatrists. MATERIALS AND METHODS: All active members of the Korean Academy of Rehabilitation Medicine were invited to complete an online survey developed after focus group discussions. RESULTS: A total of 97 physiatrists (72 males and 25 females) in Korea completed the survey. Of these, 77% reported familiarity with the term 'cancer survivors.' More than 50% of respondents reported that they provided rehabilitation services for patients with breast cancer (61.9%), brain tumors (64.9%), and spinal tumors (63.9%), whereas 86.6% of respondents reported that they had never or rarely provided rehabilitation programs for patients with gynecological, colorectal, or prostate cancer. Physiatrists who received referrals from a well-organized cooperative referral system reported providing services such as exercise programs for patients with gynecological cancer (odds ratio [OR], 2.16; p=0.044) as well as education regarding lymphedema (OR, 1.81; p=0.047) and neuropathic pain (OR, 1.96; p=0.026). CONCLUSION: Although most of the physiatrists surveyed believed that they should contribute to the management of cancer patients, they considered themselves ill equipped to provide appropriate rehabilitation services. This lack of understanding of the effectiveness of rehabilitation services for cancer patients and absence of a cooperative referral system are the major barriers to providing rehabilitation services to cancer survivors in Korea.

Implementation of Hospital Examination Reservation System Using Data Mining Technique / 대한의료정보학회지

OBJECTIVES: New methods for obtaining appropriate information for users have been attempted with the development of information technology and the Internet. Among such methods, the demand for systems and services that can improve patient satisfaction has increased in hospital care environments. METHODS: In this paper, we proposed the Hospital Exam Reservation System (HERS), which uses the data mining method. First, we focused on carrying clinical exam data and finding the optimal schedule for generating rules using the multi-examination pattern-mining algorithm. Then, HERS was applied by a rule master and recommending system with an exam log. Finally, HERS was designed as a user-friendly interface. RESULTS: HERS has been applied at the National Cancer Center in Korea since June 2014. As the number of scheduled exams increased, the time required to schedule more than a single condition decreased (from 398.67% to 168.67% and from 448.49% to 188.49%; p < 0.0001). As the number of tests increased, the difference between HERS and non-HERS increased (from 0.18 days to 0.81 days). CONCLUSIONS: It was possible to expand the efficiency of HERS studies using mining technology in not only exam reservations, but also the medical environment. The proposed system based on doctor prescription removes exams that were not executed in order to improve recommendation accuracy. In addition, we expect HERS to become an effective system in various medical environments.

Service-Oriented Security Framework for Remote Medical Services in the Internet of Things Environment / 대한의료정보학회지

OBJECTIVES: Remote medical services have been expanding globally, and this is expansion is steadily increasing. It has had many positive effects, including medical access convenience, timeliness of service, and cost reduction. The speed of research and development in remote medical technology has been gradually accelerating. Therefore, it is expected to expand to enable various high-tech information and communications technology (ICT)-based remote medical services. However, the current state lacks an appropriate security framework that can resolve security issues centered on the Internet of things (IoT) environment that will be utilized significantly in telemedicine. METHODS: This study developed a medical service-oriented frame work for secure remote medical services, possessing flexibility regarding new service and security elements through its service-oriented structure. First, the common architecture of remote medical services is defined. Next medical-oriented secu rity threats and requirements within the IoT environment are identified. Finally, we propose a "service-oriented security frame work for remote medical services" based on previous work and requirements for secure remote medical services in the IoT. RESULTS: The proposed framework is a secure framework based on service-oriented cases in the medical environment. A com parative analysis focusing on the security elements (confidentiality, integrity, availability, privacy) was conducted, and the analysis results demonstrate the security of the proposed framework for remote medical services with IoT. CONCLUSIONS: The proposed framework is service-oriented structure. It can support dynamic security elements in accordance with demands related to new remote medical services which will be diversely generated in the IoT environment. We anticipate that it will enable secure services to be provided that can guarantee confidentiality, integrity, and availability for all, including patients, non-patients, and medical staff.

Development of a Document Management System for the Standardization of Clinical Laboratory Documents

BACKGROUND: Documentation is very important; a considerable number of documents exist for use in accreditation inspection. However, most laboratories do not effectively manage the processes of documentation, organization, and storage. The purpose of this study was to facilitate the establishment of a strategically effective and sustainably standardized document management system. METHODS: A document code formatting system was modified by comparing the document list data received from 3 major university hospitals. In addition, a questionnaire regarding document code standardization was created and sent to 268 institutes to establish document classifications and generate a standard coding scheme. A computerized document management system was developed. RESULTS: Only 32% (8 out of 25 institutes) answered that they were able to identify all of the document types and their numbers. In total, 76% of institutes (19 out of 25) answered that a systematic document management system was necessary. Disorganized document files were systemized by classifying them into 8 major groups according to their characteristics: patient test records (T), test quality control (Q), manuals (M), equipment and environment management (E), statistics (S), division administration (A), department administration (R), and others (X). CONCLUSIONS: Our documentation system may serve as a basis for the standardization of documents and the creation of a document management system for all hospital laboratories.

Discrepant Causes of Death between Medical Death Certificates and Autopsy Reports (II) / 대한법의학회지

The postmortem examination certificate and death certificate provide proof of death and supply important data used to establish health statistics. However, the format of the form and the accuracy of postmortem examination and death certificates yield errors that must be corrected by comparison with postmortem studies. We reviewed 401 autopsies performed in the Department of Forensic Medicine of Chonnam National University Medical School from January 1, 2009 to December 31, 2011 and compared the reports with their postmortem examination certificates and death certificates. Of the 252 cases submitted with death certifications, 60 cases were concordant with the cause of death on the autopsy report. Eighty-nine cases had clear descriptions of the cause of death. Of these cases, 47 were from postmortem examination, 42 were from death certificates; 17 were natural deaths, 72 were unnatural. Concordance in each group was 59.6% (28/47 cases), 76.2% (32/42 cases), 41.2% (7/17 cases), and 73.6% (53/72 cases). We thus identified various types of errors in postmortem examination and death certificates. This study reveals a high rate of discrepancy between causes of death reported on death certificates and postmortem examination certificates. There are a few useful death certificate and postmortem examination certificates that can be used as a model, based on which we propose several remedies to increase the accuracy of death and postmortem examination certificates.

The Significance of Ventricular Volume in the Evaluation of Secondary Cardiomyopathy at Autopsy

BACKGROUND: The weight, shape and consistency of the heart, and the thickness of the ventricular wall are used as parameters for evaluating postmortem heart and diagnosing cardiomyopathy at autopsy. METHODS: The weight and volume of the ventricles and the thickness of the left ventricular wall of 58 hearts were measured and analyzed. RESULTS: In the group of dilated hearts, the ventricular weight, ventricular volume, ventricular volume/ventricular weight, and left ventricular volume/right ventricular volume increased, whereas ventricular wall thickness decreased. In the group of hypertrophied hearts, the ventricular weight, ventricular volume, and thickness of the ventricular wall increased but ventricular volume/ventricular weight and left ventricular volume/right ventricular volume did not change significantly. In the group of undetermined hearts, it was later found that four of the cases should have been included in the dilated heart group and another two cases in the hypertrophied heart group. CONCLUSIONS: In addition to conventional methods, the measuring ventricular volume is useful for evaluating a postmortem heart and may suggest postmortem differential diagnoses of dilated or hypertrophied forms of secondary cardiomyopathies.

Cultured human chromaffin cells grafted in spinal subarachnoid space relieves allodynia in a pain rat model / 대한마취과학회지

BACKGROUND: Implantation of xenogenic chromaffin cells into the spinal subarachnoid space can produce analgesia in neuropathic pain models. However, transplantation of xenogeneic chromaffin cell has a potential risk of viral or bacterial infections from animals to humans including encephalopathy due to prion transmission. The aim of this study was to investigate the possibility of developing a homogeneic source of therapeutic chromaffin cells. METHODS: Anti-allodynic effects of human chromaffin cells (HCCs) were evaluated in a neuropathic pain model in rats induced by chronic constriction injury of the sciatic nerve. HCCs encapsulated with alginate-poly-L-lysine-alginate were intrathecally implanted into rats (n = 10), while empty capsules were intrathecally implanted as a control (n = 8). Levels of norepinephrine from encapsulated HCCs before and after nicotinic stimulation were measured. We then perfomed a behavior test (cold allodynia) with acetone. In addition, to assess the potential contribution to pain reduction of opioid peptides released from the HCCs, all animals were injected with naloxone. RESULTS: The concentration of norepinephrine after nicotine stimulation was significantly increased compared to basal levels. Intrathecal implantation of encapsulated HCCs, significantly reduced cold allodynia as compared to rats receiving empty capsules (P < 0.05). Fifteen minutes after the injection of naloxone, cold allodynia significantly decreased in rats with HCCs (P < 0.05), while the degree of cold allodynia in control animals was unaltered. CONCLUSIONS: From these results, it appears that HCCs have a possibility as an analgesic source for transplants delivering pain-reducing neuroactive substances.

A Case of the Carotid Rupture in Procedure of Tracheostomy / 대한이비인후과학회지

In order to avoid complications of tracheostomy, it is important to treat the tendency to bleed preoperatively and to control it meticulously during the operation as well. Also, careful dissection of trachea and tracheal fenestration technique is helpful for a safe tracheostomy. Recently, the authors experienced a rare case of a ruptured common carotid artery that took place during the dissection of peritracheal soft tissues caused by a lack of operative carefulness. It was controled by suture of the common carotid artery under direct vision of the vessel with the help of CS department. The authors report it with a review of literature.

Fatal Pulmonary Thromboembolism Following Cast Immobilization of Fibular Shaft Fracture / 대한법의학회지

Pulmonary thromboembolism (PTE) is one of the most common and dangerous complications in orthopedic surgery. We experienced a fatal PTE in a 29-year-old man who had a simple fibular shaft fracture and cast immobilization for about one month. Despite simple fibular shaft fracture in patient with low risk for venous thromboembolism (VTE), a terrible outcome occurred. During immobilization, thromboprophylaxis such as low molecular weight heparin should be always considered. We report a rare case of PTE after simple fibular shaft fracture.

A Probable Community-Acquired Pneumonia due to Acinetobacter baumannii Infection Presenting the Positive Pneumothorax Test at Autopsy / 대한법의학회지

We report on a 56-year-old male laborer who injured his thorax in a construction field and complained of chest pain. About 3 weeks later, he was diagnosed as multiple rib fractures and hemothorax and found dead 3 days later at his house. At autopsy, the pneumothorax test was positive, due to not pulmonary parenchymal rupture but pleural adhesion and cavitary abscess from Acinetobacter baumannii pneumonia. Acinetobacter baumannii often causes hospital-acquired pneumonia, but rarely causes community-acquired pneumonia. This is the first report in Korea of a positive pneumothorax test at autopsy caused by community-acquired pneumonia due to Acinetobacter baumannii.

Severe back pain following surgery was successfully treated by a lumbar medial branch block : A case report / 대한마취과학회지

Lower back pain commonly develops following spinal anesthesia. This pain is likely caused by strain on the ligaments associated with paraspinous muscle relaxation and positioning during the operation. We describe a case involving a healthy 61-year-old woman with a varicose vein that was scheduled for phlebotomy under spinal anesthesia. Two days after spinal anesthesia, the patient experienced severe lower back pain that was markedly aggravated by twisting and extension of the spine, but subsided with rest. Immediately after a lumbar medial branch block was performed at the area of tenderness the pain subsided. Thease results suggest that immediate treatment of acute lower back pain is important for preventing progression to chronic low back pain.

Difficult endotracheal intubation due to an undiagnosed epiglottic cyst :A case report / 대한마취과학회지

An epiglottic cyst is a common form of laryngeal cysts which are rare causes of upper airway obstruction. A congenital laryngeal cyst always causes neonatal respiratory distress, but an acquired cyst shows very wide spectrum of symptoms such as no specific complaints, dysphagia, respiratory difficulty, or even death according to its size, location, or age. From anesthesiologists' point of view, an asymptomatic undiagnosed laryngeal cyst is a major concern. Unexpectedly, it can cause difficult airway such as 'cannnot intubate' or 'cannot intubate and cannot ventilate' situation during anesthesia. Recently we discovered an undiagnosed epiglottic cyst obscuring laryngeal inlet, leading to difficult intubation during general anesthesia for decompression and fusion of lumbar vertebrae. Fortunately, mask ventilation was possible, and after failed attempts of direct laryngoscopy, we could perform oral fiberoptic bronchoscope-aided intubation. He was discharged 10 days later with no harmful events.

Response of cerebral oximetry to increase in alveolar concentration of desflurane: effect of remifentanil and cerebrovascular CO2 reactivity / 대한마취과학회지

BACKGROUND: It is known that sympathetic stimulation and increase in cerebral blood flow velocity can be induced by desflurane. Cerebral oxygen balance could be disturbed during desflurane induction. Aim of this study was to elucidate that cerebral oxygen imbalance induced by desflurane mask induction can be reduced by combination of remifentanil and hypocapnia. METHODS: Twenty ASA 1-2 subjects were allocated randomly into 5 groups divided by concentration of remifentanil (0.0, 0.5, 1.0, 1.5, and 2.0 ng/ml). After confirmation of attaining proposed concentration of remifentanil, propofol and vecuronium were administered and mechanical ventilation was done with 8% desflurane with facial mask. Subsequently, changes in regional cerebral oxygen saturation (DeltarSO2), arterial blood pressure, heart rate, cardiac index, estimated alveolar concentration of desflurane (PDESF), and end-tidal concentration of carbon dioxide (PETCO2) were recorded for the following 10 minutes. According to concentration of desflurane and remifentanil, DeltarSO2 and hemodynamic factors were checked. RESULTS: During desflurane induction, changes in cerebral oximetry reached up to +10% (6 [first quartile], 13 [third quartile]). Arterial blood pressure, heart rate, and cardiac index were changed within clinical ranges. The DeltarSO2 showed S-shaped increasing pattern according to increasing PDESF. Hypocapnia and concentration of remifentanil reduced the maximum DeltarSO2 (P = 0.0046, P = 0.0060). Hypocapnia also shifted the curve to left (P = 0.0001). CONCLUSIONS: During 8% desflurane induction, regional cerebral oxygen saturation (rSO2) increases maximum +25%. Hypocapnia and use of remifentanil can reduce the increase in regional cerebral oxygen saturation.