Inadequate gas supply to patients with an adjustable pressure-limiting valve in the fully opened position.

With spontaneous ventilation, sufficient exhaust resistance at the adjustable pressure-limiting (APL) valve when fully opened ensures that the reservoir bag fills and adequately supplies gas to patients. A lack of exhaust resistance with the APL valve fully open caused inadequate gas supply to patients with four types of anesthesia machines: SA2 (Dräger), Excel-210 SE (GE), Fabius (Dräger), and Cato (Dräger). Mechanically, the SA2 and Excel-210 SE APL valve systems, which are of the spring-loaded disc type positioned horizontally, cannot maintain sufficient exhaust resistance with the APL valve fully open. As for the Fabius and Cato, an exhaust valve independent of the APL valve should maintain sufficient exhaust resistance continuously. However, accumulated viscous substances on the thin diaphragm of the exhaust valve contributed to hindrance of diaphragm closure.

[Effectiveness of oral tramadol hydrochloride for chronic non-malignant pain].

BACKGROUND: Tramadol hydrochloride is a centrally acting analgesic agent with two distinct mechanisms of action, a weak opioid agonist and an inhibitor of monoamine neurotransmitter reuptake, which produces significant analgesic effect synergistically. Though tramadol was approved in 1978 in Japan, it has rarely been used in clinical settings compared to foreign countries, e.g. Germany and USA. The aim of this study is to investigate effectiveness of oral tramadol for chronic non-malignant pain in Japan. METHODS: Tramadol was orally administered to patients with refractory non-malignant pain. Effects and adverse effects of tramadol were assessed about one month after the start of the administration. RESULTS: Out of 17 patients using tramadol daily, tramadol was found to be significantly effective in 4 patients (23.5%) and moderately effective in 8 patients (47.1%) from the viewpoint of pain relief as well as improvement of activities of daily livings. Side effects were reported by 7 patients (41.2%), which included nausea, constipation, and dizziness, but none of the side effects were serious. CONCLUSIONS: Tramadol is a useful option to treat non-malignant chronic pain, especially considering its very low abuse potential and a more acceptable side effect profile compared to non-steroidal anti-inflammatory drugs and opioids.

Efficacy of interdisciplinary treatment for chronic nonmalignant pain patients in Japan.

OBJECTIVES: The implementation of interdisciplinary pain management is a relatively new concept in Japan. Although there are more than 4200 pain specialists in Japan at present, no multidisciplinary pain center has yet to be established. This prospective study is, to our knowledge, the first published evaluation of the effectiveness of multidisciplinary/interdisciplinary pain treatment in Japanese patients with chronic noncancer pain. METHODS: Ninety-nine patients with chronic noncancer pain were treated by an interdisciplinary approach in a Japanese outpatient pain clinic. Treatment was on the basis of the biopsychosocial model of pain and consisted of the following components: (1) education; (2) exercise and stretch; (3) long-term and short-term goal setting; (4) medication management; and (5) cognitive and behavioral techniques for problem solving and changing maladaptive behaviors. Each treatment session was 30 minutes and was held once every 1 to 3 weeks for 8 to 12 times according to the patients' progress and availability. The patients were assessed before and 2 to 4 weeks after the treatment. RESULTS: Results showed (1) 68.9% of patients reported a significant decrease in pain, (2) 92.0% stopped using inappropriate medication including nonsteroidal anti-inflammation drugs, benzodiazepines and muscle relaxants, (3) 51.4% underwent their usual daily activities without being disturbed by pain, and (4) 75.0% who had been unemployed because of pain returned to work. Overall, the treatment succeeded in 56.8% of the patients. CONCLUSIONS: Our results suggest that an interdisciplinary treatment based upon the biopsychosocial model of pain was associated with significant improvement in multiple outcomes in this sample of Japanese patients with chronic pain.

[Facial edema and pruritus after intravenous injection of midazolam].

Midazolam is a short-acting benzodiazepine commonly used for conscious sedation for a variety of procedures. Severe adverse reactions, including respiratory depression, respiratory arrest, and anaphylactoid reaction, have been described by manufacturers. We report a patient who developed facial edema after iv injection of midazolam during caesarian section. A 26-year-old woman with a history of atopy and pollen allergy was scheduled for caesarian section. Spinal anesthesia was induced with bupivacaine without significant medical problems. Shortly after receiving 2 mg of iv midazolam 15 minutes after delivery for conscious sedation, she developed pruritus and severe facial edema. Airway obstruction did not occur and no specific medical treatment was necessary. However she was not able to open her eyes for 8 hours because of severe eyelid swelling. We should be more careful in administering midazolam which is generally regarded as safe and well tolerated.

[Anesthesia management may alter long-term outcome-review of recent reports].

Perioperative management including anesthesia may alter long-term outcome of surgical patients. We have reviewed abstracts for meeting and articles published recently concerning effects of anesthetic depth, volatile anesthetic preconditioning, beta-blockers, alpha-agonists, statins, and glucose control on long-term outcome. Although research in this area has just been started, we, anesthesiologists should recognize its importance.