The definition of Pain, “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage” (International Association for the Study of Pain : IASP, 1994), which is often used to explain its subjectivity. It is necessary to evaluate the pain objectively for diagnosis and effectiveness of therapy.
As an evaluation method of chronic pain, Visual Analog Scale (VAS) and Numerical Rating Scale (NRS) are used. Recent years, face visual analog scale and Current Perception Threshold (CPT) testing are also used commonly. Drug challenge test draws attention as it combines an evaluation method and an effective therapy. Meanwhile as a therapy of chronic pain, the reports of epiduroscopy and phototherapy are increasing. The epiduroscopy is an endoscopic operation for patients with the chronic low back pain. In Japan the therapy is performed increasingly for patients with the low back pain of spinal canal stenosis, failed back syndrome and lumbar disc herniation. Regarding the phototherapy, the reports which show the effectiveness of linear polarized infrared raytherapy and xenon phototherapy are mainly observed. Though the nerve block is still the dominant therapy in pain clinics, acupuncture therapy and phototherapy are prospected to increase their demands in future.

We investigated the usefulness of the method of producing sedation with midazolam and reversing with antagonist flumazenil in upper gastrointestinal endoscopy. Twenty-five adult outpatients underwent diagnostic upper gastrointestinal endoscopy 3 min after having an intravenous injection of 5 mg of midazolam for sedation, and received 0.25 mg of flumazenil intravenously 5 min after the removal of the endoscope. Blood pressure, heart rate, and percutaneous arterial oxygen saturation (SpO2) were measured, recorded, and compared at nine points : 1 min before midazolam injection, 2 min after midazolam injection, 1, 3, and 5 min after the insertion of the endoscope, 1 and 3 min after the removal of the endoscope, 1 min after flumazenil injection, and their awakening time at which they are easily able to respond to verbal commands. Fifteen minntes after their awakening, we asked those patients about their memory during the endoscopy and evaluated their pain with the Visual Analogue Scale (VAS). A significant decrease in systolic blood pressure was noted 2 min after midazolam injection. But the systolic blood pressure measured 1 min after the insertion of the endoscope significantly increased when compared with the level 2 min after midazolam injection. Then it gradually started decreasing. Although the systolic blood pressures 1 min after flumazenil injection and at their awakening time increased slightly, the levels were significantly lower than those 1 min before midazolam injection. The heart rate increased to the maximum 1 min after the insertion of the endoscope. Then it gradually started decreasing. The heart rates 1 min after flumazenil injection and at their awakening time decreased significantly when compared with those 1 min after the insertion of the endoscope. SpO2 significantly decreased from 97.6±1.6% 1 min before midazolam injection to 95.7±2.5% 2 min after midazolam injection and remained depressing around 95% during the endoscopy. However, SpO2 recovered 96.6±2.0% at their awakening time. Two patients had a vague memory but all the rest had no memory recollection at all of what happened during the examination. VAS was 20 mm for one patient and 0 mm for another patient. We showed the clinical usefulness of the method of antagonizing with flumazenil after upper gastrointestinal endoscopy performed on patients given an i.v. injection of midazolam, because this method might provide a minimal circulatory change due to some protection against hemodynamics stress in response to manipulation of the endoscope, anterograde amnesia, and disappearance of pain. However, we should take care of respiratory depression of the patient during endoscopy.
Minute of time ; Midazolam ; Injections ; Flumazenil ; Awake

This study aimed to estimate the cost-effectiveness of pregabalin treatment for neuropathic pain.
Design:Long-term simulations based on state transition models.
Methods:We examined the cost-effectiveness of pregabalin for treatment of three common peripheral neuropathic pains, postherpetic neuralgia(PHN), painful diabetic peripheral neuropathy(DPN), and radiculopathy, using the incremental cost-effectiveness ratio(ICER). We used quality-adjusted life years(QALYs)as an index of effectiveness, and also estimated medical costs. For PHN and DPN, we constructed state transition models comprising two states, with and without pregabalin treatment, and performed 52-week simulations. The pain scores reported in Japanese phaseIII studies were used to set patients' weekly pain scores. The results of utility surveys conducted overseas were used as utility scores, while values randomly sampled from probability distributions were used to set weekly pain scores and drop-out rates. In base-case analyses, we performed 1000 1st-order Monte Carlo simulations using 1000 values randomly sampled from probability distributions, and calculated QALYs and medical costs for 52 weeks for each group. For radiculopathy, the ICER was calculated from changes in QALYs for 12 weeks reported overseas and medical costs estimated separately for the identical period.
Results:The ICERs for PHN, DPN, and radiculopathy were 1,116,886 Yen/QALY, 1,100,420 Yen/QALY, and 1,095,943 Yen/QALY, respectively, which were well below the upper limits of ICER ranges for treatments considered cost-effective. There were no cases in which ICERs obtained from scenario and sensitivity analyses differed significantly.
Conclusion:Pregabalin was shown to be cost-effective treatment for neuropathic pain.