Effect of extradural compliance and resistance on spread of extradural analgesia

We have studied the effect of extradural compliance and extradural resistance on the spread of extradural analgesia. In 111 patients aged 21-75 yr, compliance and resistance of the extradural space were calculated by a mathematical analysis (using the Windkessel theory) of the extradural pressure-response curve to injection of a given volume of local anaesthetic. The calculated mean extradural compliance was 0.39 (SD 0.13) ml mm Hg-1 and this increased with advancing age (P less than 0.01). The total number of analgesic segments blocked was related to extradural compliance (P less than 0.01). Segmental dose requirement was related inversely to extradural compliance (P less than 0.01). Calculated extradural resistance was 26.8 (14.5) mm Hg s ml-1 and this decreased with advancing age (P less than 0.05). The total number of analgesic segments blocked was related inversely to extradural resistance (P less than 0.05). Segmental dose requirement was related to extradural resistance (P less than 0.05).

The echocardiographic assessment of left ventricular performance during sevoflurane and halothane anesthesia

The cardiovascular effects of sevoflurane were studied and compared with those of halothane in 30 healthy patients. The patients were assigned to receive 1 MAC sevoflurane (n = 10), 2 MAC sevoflurane (n = 10) or 1 MAC halothane (n = 10) in N(2)O 2 l.min(-1) and O(2) 4 l.min(-1). The changes in left ventricular diastolic and systolic dimension (Dd and Ds), fractional shortening (FS), mean velocity of circumferential fiber shortening (mVcf), left ventricular diastolic and systolic volume (Vd and Vs), stroke volume (SV), ejection fraction (EF) and cardiac index (CI) were evaluated by echocardiography. Sevoflurane produced significant dose-dependent decreases in FS, mVcf, EF and SV, but no significant changes in Dd and Vd. Therefore, the decrease in SV was due mainly to the increase in left ventricular residual volume (Vs). One MAC halothane produced a more significant decrease in FS, mVcf, EF and SV, when compared to values obtained at 1 MAC sevoflourane ( P < 0.01). CI was more significantly decreased with 1 MAC halothane than with 1 MAC and 2 MAC sevoflurane ( P < 0.01). This was brought about by a slight decrease in HR with halothane and a slight increase in HR with sevoflurane, in addition to a smaller decrease in SV with sevoflurane than with halothane. This study suggests that sevoflurane may better preserve cardiac function as a pump in healthy patients, when compared to halothane.

[Intraarterial combination immunotherapy in hepatocellular carcinoma]

Unresectable hepatocellular carcinoma (HCC) has a poor prognosis and little sensitivity to anticancer agents. We planned a combination immunotherapy, associating with rIL-2 continuous injection. Combination immunotherapy consists of 5 different biological response modifiers (BRM), i.e., rIL-2, OK-432, adriamycin (ADR), cyclophosphamide (Cy), and famotidine (Fa). rIL-2, OK-432 and ADR were administered from implantable infuser port connecting to a catheter which was injected into the hepatic artery via the gastroduodenal artery under laparotomy. OK-432, Cy, and Fa were also administered systemically. From 1988 to 1990, seven patients with unresectable HCC and two patients who underwent curative resection were treated by this therapy. The objective responses were evaluated by CT and angiography. This combination immunotherapy produced 3 cases of complete response and 2 of minor response. Immunological monitoring of lymphocyte subsets and NK activity of peripheral blood mononuclear cells was also performed. NK activity was significantly augmented and the percentage of Leu 7(-) NCD 16(+) cells increased during this therapy. Serious toxicity, but transient high fever and hypotension, was not observed during this therapy. All of these patients left the hospital within two weeks and returned to their previous job or similar life activity. These results suggest that this combination immunotherapy is worth performing in further clinical trials for hepatocellular carcinoma.

[Effect of AS-4370 on gastric emptying--double-blind clinical pharmacological study]

The effect of AS-4370 given in single doses of 2.5, 5 and 10 mg on gastric emptying was investigated using 99mTc-DTPA in healthy volunteers in the placebocontrolled double-blind crossover design. There was no difference in percent activity throughout the period of measurement between AS-4370 2.5 mg and placebo. The percent activity decreased after administration of 5 and 10 mg of AS-4370 in comparison with placebo: the decrease was found during the period from 10 to 18 minutes after start of recording at 5 mg and from 8 to 18 minutes after start of recording at 10 mg. These results demonstrated that AS-4370 at these dose levels apparently accelerated gastric emptying. The analysis of the half emptying time by the crossover method showed that only the time effect was found at 2.5 mg, whereas the half emptying time was obviously shortened at 5 and 10 mg. There was no difference between 5 mg and 10 mg. There was no finding that might warrant a caution in terms of safety. In conclusion, AS-4370 did not affect gastric emptying at 2.5 mg but apparently accelerated gastric emptying at 5 and 10 mg in healthy volunteers.

[An evaluation of absorbed doses of high energy electromagnetic radiation in radiotherapy of laryngeal cancer]

When 60Co gamma rays or high-energy X-rays are externally applied to treat laryngeal cancer, the absorbed dose at the laryngeal lumen is lower than given dose because of air space, which it should pass through, before reaching the lesion. Specially in case of high-energy X-rays, the loss of dose is considerable. Thus, the influence of the laryngeal air space on radiation dose was studied for 60Co gamma rays, 6MV X-rays and 10MV X-rays by thermoluminescent dosimetry using neck phantoms having an air cavity in the upper air way. At the anterior commissure, absorbed dose are apt to be reduced with 6MV and 10MV more than 60Co, but it is not affected by field size or anterior neck angle. In the vocal cord, the doses of 6MV and 10MV decrease in proportion to field size. In the posterior commissure, the reduction in dose varies according field size and anterior neck angle, but it is not related with radiation energy. From the above results, it is concluded that 60Co is the most suitable for radiotherapy of laryngeal cancer of these three rays, and, when high-energy X-rays above 6MV are applied, the loss of dose more than 60Co in the anterior commissure and the vocal cord should be taken into account.

[Effects of cisapride on gastric emptying]

To evaluate the effects of cisapride on gastric emptying, gastric emptying was measured in six healthy volunteers using radioisotopic techniques which were established three areas of interest, i.e. the whole stomach, the proximal stomach and the antrum. Following results were obtained. 1. At the half emptying times, cisapride induced a more rapid gastric emptying than did placebo in 5 of 6 volunteers. 2. By analyzing gastric emptying curves obtained from three areas of interest, it was suggested that cisapride enhanced the transfer of gastric contents from the proximal stomach to the antrum together with the antral emptying, so that gastric emptying was accelerated.

Relationship between sugar chain structure and biological activity of recombinant human erythropoietin produced in Chinese hamster ovary cells

Two forms of erythropoietin, EPO-bi and EPO-tetra, with different biological activities were isolated from the culture medium of a recombinant Chinese hamster ovary cell line, B8-300, into which the human erythropoietin gene had been introduced. EPO-bi, an unusual form, showed only one-seventh the in vivo activity and 3 times higher in vitro activity of the previously described recombinant human EPO (standard EPO). In contrast, EPO-tetra showed both in vivo and in vitro activities comparable to those of the standard EPO. EPO-bi, EPO-tetra, and the standard EPO had the same amino acid composition and immunoreactivity. However, structural analyses of their N-linked sugar chains revealed that EPO-bi contains the biantennary complex type as the major sugar chain, while EPO-tetra and the standard EPO contain the tetraantennary complex type as the major sugar chain. From examination of various preparations of recombinant human EPO, we found a positive correlation between the in vivo activity of EPO and the ratio of tetraantennary to biantennary oligosaccharides. These results suggest that higher branching of the N-linked sugar chains is essential for effective expression of in vivo biological activity of EPO.

[Three cases of thyroid cancer, including a component of squamous cell carcinoma]

A squamous cell carcinoma of the thyroid gland is rare and its prognosis is poor. Three cases of a rare thyroid cancer are reported, the first case being an adenosquamous cell carcinoma of a 75-year-old male and the second case being a pure squamous cell carcinoma of a 64-year-old male. These two cases were pathologically diagnosed on autopsy. The overall duration of these two cases was 6 months. The third case involved a 62-year-old male. His pathological diagnosis was a mixed squamous cell carcinoma and an undifferentiated carcinoma. Postoperatively 50 Gy of irradiation was performed. This patient is still alive and has shown no evidence of recurrence for 16 months.

[Usefulness of measurement of hepatic arterial blood flow during surgery to insert an arterial reservoir in unresectable hepatocellular carcinoma]

In a case of hepatocellular carcinoma, complicated with celiac arterial constriction, for which resection was impossible, we measured the blood flow in the hepatic artery using an ultrasonic, transit-time rheometer during surgery, and consequently inserted a reservoir safely. The measurement of the blood flow in this case demonstrated that the proper hepatic artery was provided with blood from superior mesenteric artery by the gastroduodenal artery and that the blood flow of the common hepatic artery was directed to the root part of the celiac artery. Moreover, because blood flow through the proper hepatic artery was greater while clamping the common hepatic artery than the gastroduodenal artery, cannulation was carried out from the common hepatic artery. Postoperatively, when recombinant interleukin-2(rIL-2) was infused from the reservoir, the tumor disappeared on imaging pictures, and the level of AFP (which was high preoperatively) was reduced, which was thus judged as a complete response. These results indicated the usefulness of measurement of blood flow in surgery of inserting a reservoir in cases with abnormal blood circulatory dynamics.

Gastric emptying in patients with gastric and duodenal ulcer

Gastric emptying was measured in patients with proximal gastric, distal gastric and duodenal ulcers using a radioisotopic method. Gastric emptying was rapid in patients with proximal gastric ulcer, and was considered to be due to accelerated proximal evacuation. However, emptying was delayed in patients with distal gastric ulcer, and was considered to be due to reduced emptying in the antrum. On the other hand, rapid emptying seen in duodenal ulcer patients was considered to be due to accelerated emptying in both the proximal stomach and the antrum. Gastric emptying in the healing stage was closer to that in healthy subjects than in patients with active-stage ulcer.

[Autopsy findings in 255 cases of head and neck cancer]

Two hundred and fifty-five autopsies of patients with head and neck cancers were performed at Gunma Cancer Center between 1972 and 1986. This figure accounts for 27.8% of the total number of autopsies at the Center which was 917 cases during the period. The autopsies discussed are as follows: 1) Fifty-five cases (21.6%) were oral carcinomas, 43 cases (16.9%) maxillary carcinomas, 39 cases (15.3%) laryngeal carcinomas, 32 cases (12.5%) hypopharyngeal carcinomas and finally 22 cases (8.6%) of malignant lymphomas. 2) The incidence of visceral metastases in 200 cases of squamous cell carcinoma numbered 83, including 70 cases (84.3%) of lung metastases, the most frequently observed. 3) The causes of death in head and neck cancer were primarily of two types: Twenty five cases were due to major hemorrhage as a result of carotid rupture owing to tumor invasion and its intensive irradiation. The remaining 14 deaths resulted from interstitial pneumonitis occurring during bleomycin systemic chemotherapy. The brevity of survival from the onset of symptoms would seem to indicate that, by the time head and neck cancer manifest themselves clinically, they are already at a astage of development beyond the scope of treatment.

The influence of ventricular extrasystoles and postextrasystoles on cardiovascular dynamics in anesthetized dogs

The influence of ventricular extrasystoles and postextrasystoles on cardiovascular dynamics were assessed in terms of maximum rate of rise of left ventricular pressure (max dP/dt), ascending aortic flow, left ventricular stroke volume, and left ventricular end-diastolic transverse dimension in anesthetized dogs. A single ventricular extrasystole, two and three consecutive ventricular extrasystoles (couplet and triplet) were induced by applying mechanical stimulation to the surface of the right ventricule. In any of these ventricular extrasystoles, max dP/dt, stroke volume and end-diastolic transverse dimension were decreased, compared with those in preceding sinus beats, i.e., pre-extrasystoles. Over the several postextrasystoles, max dP/dt was increased and gradually returned to its control level. This increase in max dP/dt, i.e., postextrasystolic potentiation paralleled an increase in ascending aortic peak flow but did not always bring about an increase in stroke volume, even when a left ventricular contraction was initiated by a significantly greater end-diastolic transverse dimension. The postextrasystolic potentiation seems to be associated with the Frank-Starling mechanism and does not compensate for the decreased in stroke volume elicited by the ventricular extrasystoles. In conclusion, not only ventricular extrasystoles per se but also postextrasystoles exert the adverse influence on cardiovascular dynamics consecutively.

[Effects of acute hypoxia on cardiovascular dynamics, myocardial metabolism and ECG in dogs]

In pentobarbital-pancuronium anesthetized open chest dogs, left ventricular pressure (LVP), first derivative of LVP (dp/dt) and left ventricular end-diastolic pressure (LVEDP) were measured by a micromanometer tipped catheter, stroke volume and cardiac output (CO) by an electromagnetic flow meter and coronary sinus blood flow (CSBF), by a thermal dilution catheter, respectively. Mean arterial pressure (mAP), mean pulmonary arterial pressure (mPAP), lead II of ECG and esophageal temperature were monitored. Blood gas, catecholamines and lactate of arterial blood and coronary sinus blood were measured and myocardial lactate extraction ratio (MCL) was calculated. As an index of contraction, maximum positive dp/dt (+dp/dt max), and as an index of relaxation, the time constant (T) of isovolumic left ventricular pressure fall were employed, respectively. Acute hypoxia was induced by the inhalation of a 5% O2-95% N2 gas mixture and arterial blood oxygen pressure was maintained between 15 and 20 mmHg. Along with the advancement of hypoxia, +dp/dt max, CO and mAP gradually increased and peaked in 5 minutes. Thereafter, these parameters began to decrease and CO fell to zero in 20 minutes. mPAP and HR slowly increased and peaked in 9 and in 12 minutes, respectively. T was progressively prolonged throughout the hypoxia. CSBF/CO ratio was increased and stayed at a high level even after CO began to decrease. MCL decreased and changed from positive values to negative ones in 5 minutes. Epinephrine and norephinephrine concentrations slowly increased and peaked in 16 minutes. A gradual decrease in the R wave, shortening of the R-R interval and lengthening of the QTc interval were observed in ECG. This study indicated that the left ventricular relaxing function was impaired earlier than contracting function by acute hypoxia and that conversion of the augmented left ventricular contractile state to the depressed one coincided with conversion of myocardial lactate extraction to its production.

A new technique of identifying the epidural space "dripping infusion method"

We developed a new visual technique o identifying the epidural space, using the hydrostatic pressure produced by a suspended micro-drip intravenous apparatus. When the needle pierces the ligamentum flavum, the resistance to positive pressure disappears and the saline in the apparatus flows freely into the epidural space. Thus, the entry of the needle point into the epidural space is visually confirmed by the appearance of dripping flow in the drip bulb (dripping infusion sign). This procedure was clinically evaluated at the thoraco-cervical area in 114 patients; the thoracic area in 116; and the lumbar area in 272, respectively. In 491 (97.8%) of the patients, the epidural space was identified with facility. In the remaining 11 patients (2.2%), a false dripping infusion sign appeared at the more superficial site than expected. If the pressure waveform in the epidural space is analyzed, the correct positioning of the needle can be easily confirmed. We believe that this method is one of the most accurate visual methods of identifying the epidural space and useful for teaching the epidural blockade to students and residents.

Anti-idiotypic antibodies in a patient with a well-functioning renal graft without azathioprine. II. Anti-idiotypic antibodies directed to a clonotype of a certain cytotoxic T lymphocyte

A recipient who received a renal graft from a living related donor showed good renal function for as long as 15 years after the withdrawal of azathioprine. The patient's creatinine clearance was maintained at 60 ml/min in spite of the administration of only 10 mg of predonisolon per day. Anti-idiotypic antibodies in the patient's serum were found by testing for specific inhibition of the mixed lymphocyte reaction (MLR) and cytotoxic T lymphocyte (CTL) response. The treatment of responder or effector cells with the IgG fraction from the patient's serum resulted in the specific inhibition of the MLR and CTL killing reaction against target cells of the graft donor. These findings indicate that the patient's serum contains anti-idiotypic antibodies against antigen recognition structures of a certain CTL as well as a certain MLR to donor alloantigens.