A new pattern of nerve stimulation-double burst stimulation (DBS)-to detect residual neuromuscular blockade using only with peripheral nerve stimulator was presented. The DBS consists of two short lasting, 50Hz tetanic stimuli or bursts separated by a 750msec. interval. The response to this pattern of stimulation is two single separated muscle contractions of which the second is less than the first during non-depolarizing neuromuscular blockade. The ability to identify fade manually at different train-of-four (TOF) ratios was compared in three DBS modes (DBS_2.2, DBS_3.2 and DBS_3.3) in which different numbers of impulses in the individual bursts were combined. The DBS with three and two impulses in each burst (DBS_3.2) was considered to be the most suitable mode for clinical practice especially when residual anesthesia remained.

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This investigation was conducted to know the effect of stellate ganglion block (SGB) on oxygen saturation measured by use of a pulse oximeter (SpO₂) (Ohmeda Biox 3700, U.S.A.), in comparison to oxygen saturation of arterial blood (SaO₂). Two pulse oximeters were attached to the 3rd finger of both side of 21 patients recieving SGB at pain clinic in our University Hospital. The SpO₂ for both fingers was measured shortly before SGB and after at minutes 5, 10 and 20.
SpO₂ values for both fingers showed a significant decrease at minute 5 after SGB, reading the lowest value at minute 10. The significant decrease continued for 20 minutes. The decrease in SpO₂ values were calculated to be equivalent 10 to 20mmHg of SaO₂. The value was validated by direct measurement of blood gas analysis of 4 patients. The SpO₂ values proportionally decrease to the SaO₂ values. This depleation was more evident in smaller and older patients.
Furthermore, irrespective of laterality of SGB performed, the decrease of SpO₂ values between right and left hands did not show significant difference indicating SGB cause generalized SaO₂ depletion. Further studies to answer the mechanism are now in prog-ress in our department.

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Forty-five patients in which autologous blood transfusion (autotransfusion) was used during abdominal aortic reconstruction were studied retrospectively. The autotrans-fusion system we used has two roller pumps, one for sucking shed blood from the operation field and the other for re-infusing the filtered blood with out washing. Anticoagulation was achieved with systemic administration of heparin sodium and infusion of acid-citrate-dextrose solution into the autotransfusion circuit. The average amount of autotransfused blood was 2, 282ml, which accounted for 79% of the total amount of blood transfused during the operation. 18 patients (40%) did not require homologous blood transfusion. In these 18 patients, postoperative blood analysis revealed decreases in hemoglobin concentration and platelet count, and increases in serum bilirubin concentration and alveolar-arterial Po₂ difference (A-aDo₂). Moreover, an increase in plasma beta-thromboglobulin level was observed after autotransfusion, sug-gesting an activation of platelet function. However, no patient developed serious post-operative complications such an coagulopathy, sepsis or renal dysfunction. Inconclu-sion, autotransfusion is a simple procedure, which can save the amount of homologous blood transfusion without serious complications, and may diminish transfusion related risks such as infections and allergic reactions.

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We investigated the effects of halothane and enflurane on the respiratory timing and driving mechanism in 16 patients. Under the condition of constant end-tidal anesthetic concentration (approximately 1.0 minimum alveolar concentration), respiratory par-ameters were measured. All measurements were made before the bigining of surgery. Both inspiratory time (T_I) and expiratory time (T_E) were significantly (p<0.05) longer with enflurane than with halothane anesthesia. As a result, respiratory frequency was significantly lower with enflurane anesthesia. Withdrawal of phasic vagal influence by airway occlusion revealed that Hering-Breuer inflation reflex was not operative in two groups. VT and Pmax were not significantly different between the groups. By contrast, reflecting the difference of respiratory rate, minute volume (V_E) was significantly smaller with enflurane anesthesia. The mean inspiratory flow rate (V_T/T_I) with enflur-ane was smaller than that with halothane. Consequently the value of F_ETCO₂ and Paco₂ were greater with enflurane than with halothane anesthesia. These results suggest that halothane and enflurane have different effects on the respiratory timing and driving mechanisms, and that the difference is not related to phasic vagal feedback mechanism.

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Perioperative managements for a patient, who received removal operation of a large cerebral arteriovenous malformation (AVM) which is at high risk of development of normal perfusion pressure breakthrough (NPPB), were discussed. In the case, new anesthetic technique, that is made up of high dose barbiturate anesthesia combined with blood pressure reduction to 80 or 90mmHg of systolic by using trimethaphan, was applied.
Following bolus injection of 8mg/kg of thiopental, thiopental was continuously infused at the rate of 5-8mg/kg/hour from the beginning of the operation for a few days. The hypotension was also induced at the time of excision of the AVM. And the control of blood pressure was continued for several days postoperatively. In the case, no complica-tions like bleeding and brain swelling were experienced throughout patient's postoper-ative course.
This prophylactic approach therefore seems promising for the perioperative manage-ment in the patients with large AVM, and may be prevent the occurrence of NPPB.

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We report the case of a patient (12 year old) with Klippel-Weber syndrome undergoing surgery of leg fingers.
This syndrome is characterized by: 1) a more or less extensive nevus on the involved limb, 2) varicose veins on the involved limb arising in childhood, and 3) hypertrophy of all of the tissue and especially of the bones in the impaired limb.General anesthesia was induced with dTc 3mg, thiopental 200mg and SCC 80mg under pulse oximetry monitoring. Anesthesia was maintained with N₂O-O₂-Enflurane and butorphanol 1mg. Sao₂ was over 97% during anesthesia and postoperative course was uneventful.
Preoperative assessment of systemic angiomatous lesion and careful intraoperative management are essential to assure the safety of anesthesia in a patient with Klippel-Weber syndrome.

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