[The effect of preoperative epidural morphine on postoperative pain].

Postoperative analgesia was assessed by examining nurses' records of 421 gynecological operative cases between January, 1989 and November, 1990. The criterion used in the analysis was the need for analgesics for pain within 24 hours postoperatively. After receiving morphine (2 mg, 4 mg, 5 mg, 6 mg) with local anesthetics or physiological saline solution into the epidural space (lower thoracic, lower lumbar, or both regions), the patient was intubated with thiopental, diazepam, and a muscle relaxant (vecuronium or pancuronium). Anesthesia was maintained with N2O, O2 and vecuronium or a pancuronium supplemented with a low concentration of enflurane or without enflurane. In the control group, anesthesia was maintained with an epidural block with local anesthetics and N2O, O2 supplemented with enflurane or without enflurane. In the groups receiving 2 mg or 4 mg of morphine, the percentage of patients with pain was 69.4+ (34 out of 49 cases) and 54.5% (30 out of 55 cases), respectively. Also, in the groups receiving 5 mg or 6 mg of morphine, the percentage of patients with pain was 39.5% (15 out of 38 cases) and 22.4% (51 out of 224 cases), respectively. In the control group, (with no epidural morphine) 89.1% (49 out of 55 cases) required analgesics. The percentage of patients without pain was significantly larger in the group receiving 6 mg of morphine even in comparison with the groups receiving lesser doses. No serious complications occurred postoperatively in any group. In conclusion, preoperative morphine administered into the epidural space is effective for postoperative analgesia in gynecological operation, especially when morphine 6 mg was administered in the lower epidural (4 mg) and lower lumbar epidural (2 mg) space.

Safety of ablation of the sigmoid and transverse sinuses: an experimental study.

If the sigmoid and transverse sinuses could be divided safely, surgeons could broaden their access during skull base surgery without retracting the brain extensively. We undertook this study in monkeys to assess the risk of sacrificing these sinuses. We learned that when bilateral transverse sinuses were occluded, the sinus pressure measured in the superior sagittal sinus increased significantly as blood was purged from sinus venules. Unilateral sacrifice of sigmoid and transverse sinuses, however, did not change proximal sinus pressure in any ipsilateral or contralateral sinus. Furthermore, no change in regional cerebral blood flow or motor evoked potentials was seen in the parietal lobe nor did auditory brainstem response change significantly with sinus ablation. We conclude that, unilaterally, sigmoid and transverse sinuses may be ablated safely because collateral circulation via the vein of Labbé, superior petrosal sinus, petrosal vein, and backflow from the transverse sinus to the contralateral sinus may be established.

[A successful treatment of spontaneous carotid cavernous fistula causing hemorrhagic infarction treated by detachable balloon].

A rare case of hemorrhagic infarction associated with carotid-cavernous fistula is reported. The patient was a 74-year-old female. CT scan showed hemorrhagic infarction of the left superior temporal gyrus, irregular vascular enhancement of the bilateral front-temporal lobe, and dilatation of the cavernous sinus. Left carotid angiogram revealed a high-flow left-sided CCF, cross filling to the right cavernous sinus, and intracavernous aneurysm. Bilateral front-temporal cortical veins were visualized early in the arterial phase. In this case, there was a direct shunt between the internal carotid artery and the cavernous sinus, and venous hypertension. Therefore urgent treatment using detachable balloon catheters was performed. Postoperative digital subtraction angiography revealed the disappearance of CCF. In conclusion, in CCF with cortical venous drainage there is a high possibility of developing hemorrhagic infarction. Only immediate detachable balloon occlusion can improve the outcome in elderly patients.

[A simple method of extracorporeal membrane oxygenation (ECMO)--3. The effects of pumpless ECMO (arterio-venous shunt) on arterial blood gas measured for 24 hours].

In eight anesthetized mongrel dogs, the pumpless ECMO applied between the femoral artery and vein was performed under the condition of hypoventilation for 24 hours. The methods were same as the first and second reports, except the pumpless ECMO was used. The abnormal parameters in the cardiovascular and respiratory system (blood gas analysis and end expiratory gas analysis), induced by hypoventilation, recovered to almost normal ranges, by operation of the pumpless ECMO for 24 hours. The pumpless ECMO might have such advantages over ECMO with pump as the less destruction of blood cell, easy performance and simple apparatus. In conclusion, pumpless ECMO using arterio-venous shunt may be applied clinically on respiratory distress conditions.

[A simple method of extracorporeal membrane oxygenation (ECMO)--2: The effects of ECMO (arterio-venous shunt) on the arterial blood gases measured for 24 hours].

In eight anesthetized mongrel dogs with thiopental, diazepam and pancuronium bromide, ECMO with arterio-venous shunt was performed under hypoventilation for 24 hours. The blood flow through the ECMO which was connected between the femoral artery and vein was approximately 40% of the cardiac output. Hypoventilation was induced to decrease PaO2 to around 40mmHg and increase PaCO2 to around 80 mmHg. The ECMO improved the abnormal parameters, which were induced by the hypoventilation, to almost normal range (PaO2 80mmHg, PaCO2 30mmHg) for 24 hours. Furthermore, there were no abnormalities in cardiovascular and other systems during ECMO.

[Treatment of vegetative status with dorsum column stimulation].

UNLABELLED: We have already reported that DCS (Dorsum Column Stimulation) alleviates the clinical symptoms of patients in vegetative status. Since then, we have accumulated information about 23 cases that have been treated by DCS therapy. In this paper, we describe the clinical outcome and compare cases where the treatment was effective with those where it was non-effective to evaluate the indications for further use of this treatment. RESULTS: 1) Eight of these cases showed good clinical improvement. 2) Most of the cases where the treatment was effective were young. Starting neurostimulation early brought about better clinical effects. 3) The clinical effects appeared 1-12 months after the start of the neurostimulation. 4) CT findings in the cases which had been treated effectively showed no marked cerebral atrophy, and no bilateral large diffuse low-density areas not involving the thalamus. Neither did they show any definite and large low-density areas in the brainstem. In conclusion, when the dorsum column was stimulated to treat vegetative status in which CT disclosed none of the abnormal findings described above, it increased r-CBF, enhanced the metabolism of catecholamine, and brought clinical improvement.

A pitfall in the interhemispheric translamina terminalis approach for the removal of a craniopharyngioma. Significance of preserving draining veins. Part I. Clinical study.

The interhemispheric translamina terminalis approach has made total removal of a craniopharyngioma less risky. Nevertheless, one of the pitfalls of this approach is cutting of the draining veins combined with retraction. A case of craniopharyngioma in which a subcortical hematoma developed is reported. The divided draining veins and the 60-minute retraction period were thought to have caused this complication. We therefore determined the clinical effect of cutting the draining veins and retraction on the regional cerebral blood flow and the motor nerve action potential. There were marked changes and a hematoma occurred mostly when the veins were divided and retraction was applied over the area.

A pitfall in the interhemispheric translamina terminalis approach for the removal of a craniopharyngioma. Significance of preserving draining veins. Part II. Experimental study.

The authors have reported a case of a craniopharyngioma removed by the interhemispheric translamina terminalis approach, and the postoperative development of a subcortical hematoma. We suspected that the cause of the subcortical hematoma was dividing the bridging veins and applying a retractor over them. In this paper, we report our experimental study, using dogs and monkeys, to evaluate the effect of cutting the vein and applying a retractor over it. The incidence of a subcortical hematoma was highest (60%) when the veins were cut and the retraction was applied. Vein occlusion only did not cause hematoma to develop, and the retraction alone caused 13% of the hematomas. This clearly indicated that the clinical case reported in Part I developed the subcortical hematoma postoperatively because the frontal bridging vein was cut and a retractor was applied for 60 minutes over the cut vein.

Enkephalin degrading enzymes in cerebrospinal fluid.

Enkephalins were rapidly degraded by specific enzyme systems in vivo. In cerebrospinal fluid (CSF), however, it has been undefined whether these enzyme systems existed. Our experiments showed enkephalins were hydrolyzed by the enzymatic activity in both CSF of human and monkey. The results by the thin layer chromatography and the high performance liquid chromatography revealed the reaction products of CSF and enkephalin were tyrosine, tyrosyl-glycine and tyrosyl-glycyl-glycine. Therefore, the enzymes in CSF were considered to be an aminopeptidase, a dipeptidyl aminopeptidase and a dipeptidyl carboxypeptidase. Our results suggest that in the assay of enkephalin in CSF, the effects of these enzymes should be considered.