A human almost experiences no pain when pricked by a mosquito. The detailed insertion mechanism of the mosquito proboscis was investigated based on the observation of its penetrating motion into a transparent polymer material using a high speed camera system. Among the parts of the mosquito proboscis, a center labrum and two maxillae beside it were biomimicked, creating the engineering equivalent of three microneedles by using a micromachining process. It was proven that the resistance force during insertion into an artificial skin is markedly reduced by cooperatively moving the three needles in a certain time phase to each other as the mosquito does. It is expected that pain would be reduced using the fabricated microneedles, since pain and resistance force have a positive correlation.

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  Psychosocial factors are strongly related to the onset of chronic pain, so chronicity of pain should be prevented from an early stage. However, simple methods for evaluating such psychiatric problems are limited. The Brief Scale for Psychiatiric Problems in Orthopaedic Patients (BS-POP), a simple questionnaire enabling evaluation of psychiatric problems in orthopaedic patients, was recently developed at our university. The reliability, factorial validity, criterion validity, and reproducibility of the BS-POP were studied. Orthopaedic surgeons should consider patients' psychiatric problems before operating. We should consider not only psychiatric problems but also brain dysfunctions that could be related to chronic pain.

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  Anesthesiologists have experienced difficulties in the perioperative management of patients who smoke. It has been known that smoking-related disorders such as pulmonary/cardiovascular diseases increase perioperative risk, and smoking itself could increase the risk of morbidity. However, the significance of perioperative smoking cessation is not fully understood. In the perioperative period, cigarette smokers have significantly higher risks of cardiopulmonary complications (such as pneumonia, unplanned intubation, mechanical ventilation, cardiac arrest, myocardial infarction, and stroke) and infectious complications (such as superficial/deep incisional infections, sepsis, organ space infections, and septic shock) compared to non-smokers. With regard to the duration of the preoperative smoke-free period, it was recently reported that each week of cessation could increase the magnitude of effect by 19%. In addition, it is indicated that the short-term smoking cessation at least 12 hours before surgery will eliminate problems in tissue oxygen uptake by CO and reduce the cardiovascular effect of nicotine. Thus, it is important to advise patients to quit smoking some time before surgery. We also present here a possible solution to the problem of managing anesthesia in smokers during surgery.

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  Anesthesiologists need to adjust dosing regimens of i.v. anesthetics with a basic understanding of pharmacokinetics because obesity alters the pharmacokinetics of such drugs. The results from pharmacokinetic simulations and/or target-controlled infusions for obese patients using pharmacokinetic models, which are not built for such populations, can be inaccurate. Modified pharmacokinetic models, or newly constructed pharmacokinetic models using an allometric scaling technique and/or 3/4 rule are currently being published. These models can be utilized for pharmacokinetic simulations and dose modifications of anesthetics.

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  Nitrous oxide has been used for many decades as a basic gas component of general anesthesia. Due to increased concerns about environmental pollution and possible adverse effects of nitrous oxide, however, the role of this important carrier gas has been limited in current anesthesia practice. The role of nitrous oxide was also re-evaluated after remifentanil became available in Janan. Nitrous oxide is destructive to the ozone layer as well as possessing global warming potential. However, volatile inhaled anesthetics are also recognized greenhouse gases. Desflurane has a greater potential impact on global warming than other inhaled anesthetics. Additional 60% of nitrous oxide combined with desflurane to deliver 1 MAC may decrease the 20-year environmental impact. There are specific contraindications to the use of nitrous oxide, but in the absence of these, its use with low fresh gas flow rates may still be useful in current anesthesia practice.

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  Xenon's anesthetic properties were discovered in 1946. Since then, a number of studies of xenon anesthesia have been conducted. Xenon is currently approved for clinical use as an anesthetic in Europe and may be approved in Japan in the future. Xenon has many of the properties of an ideal inhalational agent, including rapid induction and emergence, analgesic properties, cardiovascular stability, and neuroprotective qualities. On the other hand, the high cost of xenon associated with its production has discouraged more widespread use. This article reviews the advantages and disadvantages of xenon anesthesia, and discusses future perspectives.

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  Previous clinical studies on desflurane conducted in Western countries have shown that it enables faster and better recovery from anesthesia than other volatile anesthetics. Desflurane was launched in Japan in August 2011, but there have been few studies on it in clinical practice. Therefore, a retrospective comparative study was conducted in 238 patients who underwent general anesthesia with end-tracheal intubation from August 2011 to July 2012. We investigated the differential effects of desflurane and sevoflurane on time to extubation and recovery after anesthesia. Our study showed that time to extubation and recovery in patients administered desflurane was significantly shorter than in patients administered sevoflurane. The use of desflurane may also improve the quality of recovery from anesthesia for Japanese patients.

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  More than 20 years have passed since the laryngeal mask airway (LMA) was developed. It was expected to increase opportunities to use supraglottic airway devices (SADs) in pediatric anesthesia practices. Insertion of a SAD is generally easier and less invasive than tracheal intubation, but the safe use of SADs in pediatric patients requires an understanding of the anatomical features of the pediatric airway and how to deal with predictable airway problems such as laryngospasm. To date, various SADs have been developed. The features of each device must be understood to ensure its effective use. For the purpose of using pediatric SADs safely and effectively, it is important to be trained in pediatric anesthesia practice and in the handling of SADs.

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  Many anesthesiologists hesitate to use supraglottic airway (SGA) in pediatric anesthesia. SGA is an attractive device because of its ability to secure the airway without neuromuscular blockade for short duration surgical procedures. Other benefits of SGA are feasibility and low risk of airway injury. On the other hand, SGA has disadvantages such as uncertainly in securing the airway and fitting, laryngospasm, and risk of pharyngeal injury. Even anesthesiologists who are used to using SGA in adult patients may prefer tracheal intubation to SGA for children. This review summarizes points to note and procedures to use when using SGA in children.

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  Though several useful airway devices for pediatric patients have been developed, there are still some difficulties associated with device insertion in pediatric patients, who have a higher position of the larynx inside the throat (C2-3), a larynx that is more angled over the glottis, a cone-shaped larynx, long epiglottis and hypertrophy of the adenoids. The I-gel, which has a soft, gel-like, non-inflatable cuff, is a second generation supraglottic airway. The smallest I-gel was developed for neonates. We would like to introduce our initial clinical evaluation of the I-gel in pediatric patients. The overall insertion success rate at the first attempt was 98% by residents. Leak pressure was 22±1 cm H₂O. The tidal volume per body weight was 22±1 ml/kg. A good view by the fiberscope was achieved in 76% of cases. These results show that the i-gel airway is safe and effective for pediatric patients. I would also like to discuss how to manage the airway in pediatric patients with upper respiratory infections.

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  It is known that psychosocial factors such as mental health, stress and job satisfaction are strongly related to the onset of increase and chronicity of pain. Psychiatric problems should be evaluated from an early stage. The Brief Scale for Psychiatric Problems in Orthopaedic Patients (BS-POP) is a simple questionnaire and a useful tool for quick and easy evaluation to assess patients' psychiatric problems. In addition, the presence of structural disorders of the brain in chronic pain patients should be investigated. Multidisciplinary evaluation of various types is indispensable to assess a patient's background for chronic pain.
  It is important to address psychological and social problems in order to relieve pain and improve quality of life from an early stage.

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  FiRST (Fibromyalgia Rapid Screening Tool) is a brief questionnaire comprised of six “yes/no” questions for the detection of fibromyalgia syndrome, although it requires further validation among various chronic pain syndromes for clinical use. After authorized translation into Japanese and FiRST authorization for academic use, we used the Japanese FiRST in our chronic pain outpatients as questionnaires. The FiRST questionnaire was used to assess 81 patients with chronic pain due to fibromyalgia (n=11), and the results compared with other chronic pain patients (n=70). A cut-off score of 5 (the number of positive items) identified fibromyalgia patients with a sensitivity of 100% and a specificity of 71.6%. Each of the six questions revealed a significant difference (Fisher-test) in comparison between fibromyalgia and another chronic pain syndromes group. In conclusion, FiRST is a simple questionnaire with excellent discriminative value in daily practice, comprehensively delineating fibromyalgia. However, it is not good enough to use as the sole diagnostic tool.

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  This study describes the roles of anesthesiologists in efficient perioperative management. Surgical services are the largest source of revenue for acute care hospitals, and anesthesiologists need to play a central role in the efficient management of operating rooms. Standardization is a prerequisite to achieve efficiency. Standardization may include not only structure, design, and management of operating rooms ; management of medical equipment and supplies but also perioperative management modalities such as ERAS protocol. However, the promotion of efficiency may compromise safety. As leaders of the perioperative management team, anesthesiologists must contribute to faster recoveries and shorter hospital stays of patients, and they must also aggressively practice the safety measures of perioperative management.

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  An increasing number of hospitals have recently revised the duration of preoperative fasting and introduced oral carbohydrate loading just prior to surgery. Although our hospital has done the same, we have faced several problems related to these changes, and found it necessary to discuss in detail the definition of clear fluid, cases to be excluded, and specifics of the time period during which patients cannot drink before surgery. In addition, it is important to determine how to check the preoperative fasting instructions provided by the anesthesiology department so that, for example, patients with gastrointestinal obstruction are not allowed to drink anything. Finally, the method of instructing the patient when the carbohydrate loading drink is to be delivered as a meal remains to be determined. For effective introduction of oral carbohydrate loading just prior to surgery, these problems must be addressed.

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  Preoperative 12.6% oral carbohydrate loading is an element of the Enhanced Recovery After Surgery (ERAS) protocol aimed at alleviating postoperative insulin resistance. In this study, we investigated the effectiveness of 18% carbohydrate loading in alleviating insulin resistance. Six healthy volunteers participated in this crossover-randomized study and were segregated into 2 groups : volunteers in the carbohydrate-loading group (group A) who fasted from after 9 pm and ingested 375 mL of a beverage containing 18% carbohydrate (ArginaidWater^TM ; Nestle, Tokyo, Japan) between 9 pm and 12 pm and 250 mL of the same at 6.30 am and volunteers in control group (group B) who were allowed to drink only water. At 8.30 am, a hyperinsulinemic normoglycemic clamp was initiated. The glucose infusion rate (GIR) was evaluated as a marker of insulin resistance. The GIR in group A was significantly higher than in group B (11.5 ± 2.4 vs. 6.2 ± 2.2 mg/kg/min, p = 0.005). In conclusion, preoperative 18% carbohydrate loading could prevent a decrease in insulin sensitivity and suppress catabolism in healthy volunteers. Thus, carbohydrate loading with a beverage with 18% carbohydrate content might contribute to improvements in perioperative management.

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  We compared the effect and necessary amount of preoperative oral rehydration solution (OS-1^® [OS1] and Arginaid^® water [AW] ) in perioperative management. Study subjects included patients undergoing total hip arthroplasty with spinal anesthesia planned for the afternoon. In Study 1, 40 patients were randomized into 2 groups : OS1 1,000 ml (n=20) and AW 1,000 ml (n=20). In Study 2, 40 patients were randomized into 2 groups : AW 1,000 ml (n=20) and AW 250 ml (n=20). Results of both studies showed no significant difference in ΔFENa (fractional excretion of sodium). We concluded that the two solutions are suitable as preoperative oral rehydration solutions in perioperative management and that both 1,000 ml and 250 ml of AW compensated equally for dehydration. Consequently, drinking 1,000 ml of fluid as dehydration therapy may be unnecessary.

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  The wrong drug during anesthesia is the most common adverse event, and many of these errors are due to syringe swaps. As one measure to prevent the wrong drug from being selected and administrated, standardized color codes for prepared drug syringe labels have been introduced in many countries. Since Professor Foster PA at the University of Stellenbosch in South Africa created the original concept for the color code in the 1980s, international standards for color coding have spread to several countries. Since the ISO (International Organization for Standardization) formulated the ISO26825 in 2008, recommendations in many countries have been revised to align with the ISO standard.
  We reviewed the literature on the standardized color code of drug syringes, and summarized the history of the enactment, also would suggest the introduction of a color code standard in Japan.

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  A 73-year-old man with severe mitral regurgitation underwent laparoscopic adrenalectomy for an adrenaline predominant pheochromocytoma. After inducing anesthesia, we monitored his cardiac index and central venous oxygen saturation using a PreSep Catheter^TM and FloTrac^TM. During surgical manipulation around the tumor, phentolamine was infused intermittently because blood pressure and systemic vascular resistance increased. After the tumor was removed, dobutamine was required to keep blood pressure and cardiac index at normal levels. Monitoring these levels may contribute to anesthetic management of pheochromocytoma with mitral regurgitation.

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  We experienced a case of malignant hyperthermia (MH) after pediatric cardiac surgery that was difficult to diagnose. MH has declined with improvements in anesthesia in recent years, but it is still a lethal intra- and post-operative complication. The signs of MH are often overlooked during cardiac surgery. In addition, it takes a long time to perform skeletal muscle and genetic tests in Japan. In this case, we strongly suspected MH but the results of genetic tests were negative. If we suspect MH, we should take rapid action without a definitive diagnosis during surgery for congenital cardiac anomalies.

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  We report a case of epidural hematoma in an elderly patient with severe vertebral deformation. An 84-year-old woman suffered from pain caused by herpes zoster. She had a past history of L1 fracture and spinal canal stenosis. She had normal bleeding time, coagulation test, and platelet count. She underwent a single epidural block for treatment without difficulty.
  On the way home from the hospital she started having back pain. Most of the pain was relieved by medication, but she continued to experience slight back pain and weakness of her lower limbs. MRI of the spine demonstrated a small (12×7×39 mm) hematoma at Th12, just above the fracture of L1. We believe that the severe vertebral deformation prevented blood from spreading vertically and that a small volume hematoma resulted in compression on the spinal cord. Patients with severe vertebral deformation including fracture or spinal canal stenosis have a potential risk for neurological complications by hematoma after epidural block, so adequate care should be taken in treating such patients.

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  We conducted a survey about the attitudes toward cardiopulmonary resuscitation (CPR) of medical staffs who participated in the AHA-BLS Healthcare Provider Course (HCP). Almost all participants had recognized the importance of calling for help or activating emergency response system even before taking the AHA-BLS-HCP. AHA-BLS-HCP significantly improved positivity toward starting CPR to strangers (P<0.001). Hesitation about rescue breathing to family did not change (P=0.232), but concern about infection and hesitation about mouth-to-mouth ventilation to strangers significantly decreased after the AHA-BLS-HCP (P<0.001, P=0.047). Almost all participants considered education of citizens regarding CPR to be important. Furthermore, positive attitudes to actual instruction to citizens were significantly improved (P=0.004). The AHA-BLS-HCP may improve the positivity of medical staff toward activating emergency response system, giving mouth-to-mouth ventilation and educating citizens with regard to CPR.

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  The American Society of Anesthesiologists released practice guidelines for management of the difficult airway in February 2013. Members of the Japanese Association for Medical Simulation have translated this guideline into Japanese, and the guideline is presented in this issue. The differences between this guideline and the previous guideline and the underlying evidence that influenced the revision are discussed in this review.

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