The effects of intrinsic nitric oxide on cardiac neural regulation in cats

In this study, we aimed to elucidate the effects of intrinsic nitric oxide (NO) on cardiac neural regulation. Twenty-two cats were anesthetized with 1.5% isoflurane and allocated to Group I (intact; n = 7), Group D (denervated baroreceptors and vagi; n = 8), or Group B (autonomic blockade with i.v. hexamethonium, propranolol, and atropine; n = 7). Cardiac sympathetic nerve activity (CSNA), mean arterial pressure (MAP), sinus heart rate (HR), and A-H and H-V intervals during pacing (150 bpm) were measured before and after i.v. administration of a NO synthase inhibitor, NG-nitro-L-arginine (L-NNA, 30 mg/kg) and after reversal with an excessive dose of L-arginine (300 mg/kg), before and during intermittent electrical stimulation of the posterior hypothalamus. L-NNA significantly increased MAP in Groups I and B, but not in Group D. L-NNA significantly decreased HR and lengthened A-H in Group I, but not in other groups. L-arginine further decreased HR and lengthened A-H unexpectedly. The reasons for these findings could not be determined in this study. L-NNA did not change CSNA. Hypothalamic stimulation did not potentiate L-NNA-induced changes in CSNA, hemodynamic variables, and atrioventricular conduction. In conclusion, intrinsic NO may modulate atrioventricular conduction and sinus rate through a vagal cholinergic, rather than a nonautonomic mechanism.

IMPLICATIONS

Elucidating the roles of intrinsic nitric oxide (NO) on cardiac neural regulation is important. In intact, vagotomized, and baroreceptor-denervated or pharmacologically autonomic blockaded cats, an NO synthesis inhibitor was administered, and atrioventricular conduction and cardiac sympathetic neural discharge were measured. The results suggest a vagal cholinergic mechanism of intrinsic NO.

Involvement of vascular endothelial growth factor and urokinase-type plasminogen activator receptor in microvessel invasion in human colorectal cancers

To evaluate the association among known angiogenic growth factors or factors related to the plasminogen activation system and clinicopathological factors in patients with colorectal cancer, we examined the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), transforming growth factor-alpha (TGF-alpha), urokinase-type plasminogen activator (u-PA), u-PA receptor (u-PA-R) and plasminogen activator inhibitor-1 (PAI-1) in clinical specimens of colorectal cancers by Northern blot analysis. In comparison with the expression of these angiogenesis-related genes in 7 paired samples of colorectal cancers and the adjacent normal mucosa, VEGF mRNA level was significantly higher in the cancer tissues than in the adjacent normal mucosa (p < 0.05). We analyzed expression of these genes in 44 cases of primary colorectal cancers. Among the 3 angiogenic growth factors we examined, VEGF mRNA expression was significantly higher in the cancer tissues with blood vessel invasion or with lymphatic vessel invasion than in those without, respectively (p < 0.05). On the other hand, u-PA-R mRNA expression was significantly higher in the cancers with blood vessel invasion than in those without (p < 0.05). In addition, there was a correlation between the expression levels of VEGF and u-PA-R mRNA in the cancer tissues we have examined. Using immunohistochemistry, strong staining of VEGF or u-PA-R was observed in the cancer cells invading the microvessels. Our findings suggest that malignant transformation might accompany the upregulation of VEGF expression in colorectal cancers and that VEGF and u-PA-R might contribute cooperatively to increase angiogenesis around the tumor as well as the metastasis via microvessels.

[Telomerase activity in benign proliferative breast disease and breast cancer]

The application of telomerase activity is expected to serve as a reliable indicator of biological malignancy in breast tumors. We performed a study to quantify telomerase activity, the results of which revealed that this activity tends to be unexpectedly low in scirrhous carcinoma having low histological differentiation. It is therefore felt that additional studies at the tissue level using in situ hybridization will be required in the future. Although we think that atypical cystic duct is a true pre-cancerous lesion in the sense of having a high possibility of progressing into breast cancer, it will be interesting to determine whether or not the tissue is composed of cells having telomerase activity.

Involvement of vascular endothelial growth factor and urokinase-type plasminogen activator receptor in microvessel invasion in human colorectal cancers

To evaluate the association among known angiogenic growth factors or factors related to the plasminogen activation system and clinicopathological factors in patients with colorectal cancer, we examined the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), transforming growth factor-alpha (TGF-alpha), urokinase-type plasminogen activator (u-PA), u-PA receptor (u-PA-R) and plasminogen activator inhibitor-1 (PAI-1) in clinical specimens of colorectal cancers by Northern blot analysis. In comparison with the expression of these angiogenesis-related genes in 7 paired samples of colorectal cancers and the adjacent normal mucosa, VEGF mRNA level was significantly higher in the cancer tissues than in the adjacent normal mucosa (p < 0.05). We analyzed expression of these genes in 44 cases of primary colorectal cancers. Among the 3 angiogenic growth factors we examined, VEGF mRNA expression was significantly higher in the cancer tissues with blood vessel invasion or with lymphatic vessel invasion than in those without, respectively (p < 0.05). On the other hand, u-PA-R mRNA expression was significantly higher in the cancers with blood vessel invasion than in those without (p < 0.05). In addition, there was a correlation between the expression levels of VEGF and u-PA-R mRNA in the cancer tissues we have examined. Using immunohistochemistry, strong staining of VEGF or u-PA-R was observed in the cancer cells invading the microvessels. Our findings suggest that malignant transformation might accompany the upregulation of VEGF expression in colorectal cancers and that VEGF and u-PA-R might contribute cooperatively to increase angiogenesis around the tumor as well as the metastasis via microvessels.

Changes in thyroid function and immunological parameters long after subtotal thyroidectomy for Graves' disease

OBJECTIVE

To find out whether subtotal thyroidectomy results in long term stable functional and immunological remission in patients with Graves' disease.

DESIGN

Retrospective study.

SETTING

Teaching hospital, Japan.

SUBJECTS

176 patients who underwent subtotal thyroidectomy for Graves' disease, 1970-79.

INTERVENTION

Follow up surveys in 1984 and 1992.

MAIN OUTCOME MEASURES

Changes in thyroid function, antibody titres, and lymphocyte subsets.

RESULTS

29/79 patients (39%) who were euthyroid in 1984 had evidence of thyroid dysfunction in 1992. Of the 8 patients with latent hypothyroidism in 1984, 3 (38%) had become euthyroid by 1992, and none required treatment. Of the 29 patients who were hypothyroid in 1984, 5 had latent hypothyroidism and 1 was euthyroid in 1992, and of the 18 patients with recurrent hyperthyroidism in 1984, 1 had become euthyroid by 1992. The number of positive titres to TSH-binding inhibitory immunoglobulin was significantly higher in the recurrence group (31/36, 86%) compared with the hypothyroid (7/26, 27%), latent hypothyroidism (8/37, 22%), and euthyroid (22/77, 29%) groups (p < 0.01). There were also significant differences in the mean (SD) number of Leu HLA DR subsets between the control (17 (3), n = 18) and recurrence (21 (6), n = 38), hypothyroid (22 (6), n = 35), latent hypothyroidism (22 (6), n = 22), and euthyroid (22 (9), n = 64) groups (p < 0.002). There were no differences in the number of T cell subsets among the groups.

CONCLUSION

Treatment of Graves' disease by subtotal thyroidectomy does not necessarily result in stable late functional or immunological remission. Long term follow up of such patients may be necessary.

Expression of fibroblast growth factor-2 and fibroblast growth factor receptor-1 in thyroid diseases: difference between neoplasms and hyperplastic lesions

We studied the expression of both fibroblast growth factor-2 (FGF-2) and FGF receptor-1 (FGFR-1) in various histological types of human thyroid neoplastic and hyperplastic tissues to clarify the biological behavior of FGF-2. A total of 37 malignant tumors (24 papillary carcinomas, 10 follicular carcinomas, 3 anaplastic carcinomas), 8 follicular adenomas, and 12 adenomatous goiters were examined by immunohistochemical methods. With immunohistochemical staining, both FGF-2 and FGFR-1 were frequently detected in human thyroid carcinoma (79.2 to 100% and 80 to 100%, respectively). In thyroid hyperplastic lesions such as adenomatous goiter, the FGF-2 immunoreactivity in follicular cells was detected in 2 of 12 adenomatous goiters (16.7%). In contrast, FGFR-1 immunoreactivity was detected in 66.7% of cases of this disease. The endothelial cells of microvessels in the stroma adjacent to the neoplasms and hyperplastic lesions also showed cytoplasmic FGF-2 immunoreactivity. The difference between FGF-2 and FGFR-1 expression in adenomatous goiters was statistically significant (P<0.05). Furthermore, the difference in FGF-2 immunoreactivity between carcinoma and adenomatous goiter was statistically significant (P=0.0001). The present investigation demonstrated the possibility of an autocrine mechanism of action of FGF-2 in human thyroid carcinoma. Moreover, in thyroid hyperplastic lesions, FGF-2 derived from the stroma might be involved in the formation of nodular and/or diffuse goiters.

Thoracic duct cyst in supraclavicular region

A 28-year-old female attended an outpatient clinic in October, 1989, because of a tumor in the left supraclavicular fossa, detected in a health examination. Following exploratory puncture of the tumor which yielded milky-white fluid, suggesting a cyst in the thoracic duct, she was admitted to our department. The cyst was unilocular measuring about 6 cm in diameter, and the fluid content was chyle-rich in lipids. Lymphography demonstrated a lymphatic structure adjacent to the lesion and scattered lymph vessels on the cyst surface. On November 16 the cyst was resected. A restiform structure was observed between the cyst and the thoracic duct, but the presence or absence of communication was unclear. The histological diagnosis was thoracic duct cyst. Thoracic duct cyst occurring in the cervical region is very rare. Our case may provide useful information as to its pathogenesis and the mode of retention of cyst fluid.

Postoperative outcome of insufficient surgery for small differentiated thyroid carcinoma

We performed conservative surgery for small differentiated thyroid carcinoma, but also inadvertently carried out minimal insufficient surgery, such as enucleation (Ex) or partial lobectomy (pLx) without regional node dissection for malignant thyroid nodules. In this study, the long-term postoperative outcome after such insufficient surgical treatment was evaluated. Of 348 patients with differentiated thyroid carcinoma who underwent initial surgery between 1953 and 1976, 84 underwent either Ex or pLx and their records are herein reviewed. The frequency of recurrence from the remnant gland or regional lymph nodes was examined in relation to the tumor diameter (< or = 1.0 cm, tis; 1.0 cm-2.0 cm, t1; > 2.0 cm, t2). After Ex/pLx, the recurrence rate in the tis group was 13.3% and not significantly different from that (13.6%) in the t1 group. The recurrence rate was notably increased in the t2 group. Moreover, there was no significant difference between the recurrence rate in the tis and t1 groups after Ex/pLx and that after lobectomy with nodal dissection. These results suggest that a reoperative procedure with a more extensive thyroidectomy and neck dissection might not necessarily be required immediately after minimal insufficient surgery is inadvertently carried out in patients with small differentiated thyroid carcinoma measuring 2.0 cm in diameter or less.

Genotyping of the CYP1A1 and GSTM1 genes in esophageal carcinoma patients with special reference to smoking

BACKGROUND

Aromatic hydrocarbons, including benzol[a]pyrene, in tobacco smoke first require metabolic activation by phase I enzymes, cytochrome P450s (CYP450s), and then are subjected to detoxification by phase II enzymes, the glutathione-S-transferases. A high risk lung carcinoma group has been reported to have specific polymorphisms of the cytochrome P450 (CYP1A1) gene and the glutathione-S-transferase (GSTM1) gene. In this study, the authors investigated whether such genotypes were also risk factors for esophageal carcinoma.

METHODS

Subjects were comprised of 89 esophageal carcinoma patients and 137 noncancer controls. Forty-nine of the patients and 60 of the control subjects were smokers. Genotypic studies of both CYP1A1 and GSTM1 were performed in the cancer tissues of all 89 patients. Genotypes of peripheral blood leukocytes taken from the control subjects were also determined. Genotypes of the CYP1A1 and GSTM1 genes were determined by the polymerase chain reaction.

RESULTS

Patients who were heavy smokers with the genotypes Val/Val (V/V) for CYPIAI and the combined genotype of V/V for CYP1A1 and GSTM1- were a statistically high risk group compared with control subjects (P < 0.01, chi-square = 10.6 vs. P < 0.01, chi-square = 11.0). The association of V/V for CYPIAI with a smoking index > or = 600 in esophageal carcinoma patients was estimated at 6.63 (95% confidence interval [CI], 1.86-23.7). The association of combined genotypes of V/V of CYP1A1 and GSTM1 with a smoking index > or = 600 in esophageal carcinoma patients was estimated at 12.7 (95% CI, 1.97-81.8)

CONCLUSIONS

Specific genotypes of the CYP1A1 and GSTM1- genes are related to the incidence of esophageal carcinoma, especially in heavy smokers.

Genotyping of the CYP1A1 and GSTM1 genes in esophageal carcinoma patients with special reference to smoking

BACKGROUND

Aromatic hydrocarbons, including benzol[a]pyrene, in tobacco smoke first require metabolic activation by phase I enzymes, cytochrome P450s (CYP450s), and then are subjected to detoxification by phase II enzymes, the glutathione-S-transferases. A high risk lung carcinoma group has been reported to have specific polymorphisms of the cytochrome P450 (CYP1A1) gene and the glutathione-S-transferase (GSTM1) gene. In this study, the authors investigated whether such genotypes were also risk factors for esophageal carcinoma.

METHODS

Subjects were comprised of 89 esophageal carcinoma patients and 137 noncancer controls. Forty-nine of the patients and 60 of the control subjects were smokers. Genotypic studies of both CYP1A1 and GSTM1 were performed in the cancer tissues of all 89 patients. Genotypes of peripheral blood leukocytes taken from the control subjects were also determined. Genotypes of the CYP1A1 and GSTM1 genes were determined by the polymerase chain reaction.

RESULTS

Patients who were heavy smokers with the genotypes Val/Val (V/V) for CYPIAI and the combined genotype of V/V for CYP1A1 and GSTM1- were a statistically high risk group compared with control subjects (P < 0.01, chi-square = 10.6 vs. P < 0.01, chi-square = 11.0). The association of V/V for CYPIAI with a smoking index > or = 600 in esophageal carcinoma patients was estimated at 6.63 (95% confidence interval [CI], 1.86-23.7). The association of combined genotypes of V/V of CYP1A1 and GSTM1 with a smoking index > or = 600 in esophageal carcinoma patients was estimated at 12.7 (95% CI, 1.97-81.8)

CONCLUSIONS

Specific genotypes of the CYP1A1 and GSTM1- genes are related to the incidence of esophageal carcinoma, especially in heavy smokers.

Crush syndrome sustained in the 1995 Kobe, Japan, earthquake; treatment and outcome

STUDY OBJECTIVE

To assess the treatment and outcome of patients with crush syndrome sustained in an earthquake disaster.

METHODS

We conducted a retrospective analysis of eight patients with crush syndrome and subsequent acute kidney failure who were treated in the ICU of a university hospital. All eight patients had been extricated from buildings that collapsed in the 1995 Kobe, Japan, earthquake. Crush injury involved the upper extremities in one patient and the lower extremities in seven. Each patient received intravenous fluid infusion and diuretic drugs and underwent hemodialysis. Emergency fasciotomy was performed in some patients, 17 to 100 hours after extrication.

RESULTS

All patients were conscious and lucid on admission, and blood pressure and heart rate were normal. All the patients demonstrated kidney failure with increased concentrations of serum creatinine (1.9 to 9.6 mg/dL [169 to 852 mumol/L]). Six patients were oliguric. Hyperkalemia (5.6 to 8.8 mEq/L) was present in six patients. We found close correlations between the serum potassium and creatine kinase concentrations, between the serum myoglobin and potassium concentrations, and between the serum myoglobin and creatine kinase concentrations. All the patients were weaned from hemodialysis. The serum creatinine concentration decreased to a normal level within 20 to 52 days of admission in all patients. No patients underwent amputation. Muscle weakness and sensory deficits persisted in all patients 6 months after the earthquake.

CONCLUSION

Our findings support current therapeutic strategies for crush syndrome, despite the long delay to initiation of intensive therapy. All the patients recovered kidney function and were weaned from hemodialysis; none required amputation.

Genotyping of the CYP1A1 and GSTM1 genes in esophageal carcinoma patients with special reference to smoking

BACKGROUND

Aromatic hydrocarbons, including benzol[a]pyrene, in tobacco smoke first require metabolic activation by phase I enzymes, cytochrome P450s (CYP450s), and then are subjected to detoxification by phase II enzymes, the glutathione-S-transferases. A high risk lung carcinoma group has been reported to have specific polymorphisms of the cytochrome P450 (CYP1A1) gene and the glutathione-S-transferase (GSTM1) gene. In this study, the authors investigated whether such genotypes were also risk factors for esophageal carcinoma.

METHODS

Subjects were comprised of 89 esophageal carcinoma patients and 137 noncancer controls. Forty-nine of the patients and 60 of the control subjects were smokers. Genotypic studies of both CYP1A1 and GSTM1 were performed in the cancer tissues of all 89 patients. Genotypes of peripheral blood leukocytes taken from the control subjects were also determined. Genotypes of the CYP1A1 and GSTM1 genes were determined by the polymerase chain reaction.

RESULTS

Patients who were heavy smokers with the genotypes Val/Val (V/V) for CYPIAI and the combined genotype of V/V for CYP1A1 and GSTM1- were a statistically high risk group compared with control subjects (P < 0.01, chi-square = 10.6 vs. P < 0.01, chi-square = 11.0). The association of V/V for CYPIAI with a smoking index > or = 600 in esophageal carcinoma patients was estimated at 6.63 (95% confidence interval [CI], 1.86-23.7). The association of combined genotypes of V/V of CYP1A1 and GSTM1 with a smoking index > or = 600 in esophageal carcinoma patients was estimated at 12.7 (95% CI, 1.97-81.8)

CONCLUSIONS

Specific genotypes of the CYP1A1 and GSTM1- genes are related to the incidence of esophageal carcinoma, especially in heavy smokers.

Germline mutations of the APC gene in two Japanese adenomatous polyposis patients

Germline mutations of the adenomatous polyposis coli (APC) gene have been reported in patients with familial adenomatous polyposis (FAP) and are believed to be an early event in colorectal carcinoma. We report the results of screening for germline mutations of the APC gene in 4 cases of 2 kindreds using non-radioactive PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism) analysis. The mutation in kindred 1 was a 4 bp deletion at codon 849 in exon 15, resulting in a frameshift leading to truncation of the APC gene product. In kindred 2, a transversion of C to G at codon 2038 was observed, resulting in an amino acid change from leucine to valine. In this case, it is possible to screen presymptomatic diagnosis easily and quickly by digestion with restriction enzyme EcoNI.

Development of Graves' disease after surgical treatment for thyroid nodules: report of four cases

We report herein rare cases who developed hyperthyroid Graves' disease after surgical treatments for thyroid nodules. We have seen only 4 such cases in the course of 1680 consecutive cases (0.24%) of thyroidectomies in which partial thyroidectomy was carried out from 1966 to 1993. It is of interest that because 2 of these three cases (67%) were associated with positive TGHA and/or MCHA at the time of surgery, the presence of autoimmune thyroiditis may predispose to Graves' disease, but surgical treatment of the thyroid glands may not be related to the development of Graves' disease, because the hyperthyroid symptoms appeared 2 to 27 years (mean: 12 years) after the surgery.

The disturbances of object vision and spatial vision in Alzheimer's disease

Thirty-one patients with mild-to-moderate Alzheimer's disease (AD) underwent a test battery of complex visual tasks. We assessed the scores using a principal-factor analysis to elucidate the underlying deficits. There were three independent factors: The first factor included the tasks of identifying and comparing forms of visual stimuli. The second factor consisted of digit span and digit symbol tasks, and the third factor consisted of a specified visual counting task. We considered these three factors as representing the dysfunctions of object recognition, general attention and spatial recognition, respectively. These results underline the disturbances of the two visual systems, object vision and spatial vision, in early-AD patients.

[Acute angle-closure glaucoma after total hip replacement surgery]

Acute angle-closure glaucoma is a rare complication of surgery. We experienced a case of postoperative acute glaucoma after total hip replacement under general anesthesia. A 49-year-old female without signs or symptoms of glaucoma was premedicated with the intramuscular administration of secobarbital, atropine and ranitidine. Following rapid induction with thiopental and vecuronium, anesthesia was maintained with N2O-O2-sevoflurane. PGE1 was administered intravenously for induced hypotension during the surgery. Hemorrhagic shock with a systolic blood pressure of 60 mmHg continued for 15 min during the surgery. Large amounts of fluid and ephedrine were required for treating this hypotensive episode. Vecuronium was reversed by bolus injection of neostigmine and atropine at the end of surgery. Soon after recovery from anesthesia, she complained of pain and blurred vision in her both eyes. The consulting ophthalmologist made a diagnosis of acute glaucoma due to high intraocular pressure (IOP). Treatment with glycerol and pilocarpine had no effect on the elevated IOP. The laser iridotomy performed on her at 5th and 7th post-operative days improved her vision completely. The post-operative glaucoma may cause serious permanent loss of vision. An early diagnosis of this post-operative complication and its treatment with drugs and surgery should be emphasized.

Lidocaine-induced hemodynamic effects are enhanced by the inhibition of endothelium-derived relaxing factor in dogs

BACKGROUND

Lidocaine has been shown to have direct vasoconstrictive effects at low concentrations. Since lidocaine inhibits endothelium-dependent vasodilation in vitro, the vasoconstrictor effect of lidocaine may be due to inhibition of endothelium-derived relaxing factor(EDRF/NO). Therefore, the current study was designed to determine the effects of NG-nitro-L-arginine (L-NNA), a potent inhibitor of nitric oxide synthase, on systemic and pulmonary hemodynamics during lidocaine infusion.

METHODS

Systemic and pulmonary hemodynamic effects of lidocaine infusion, 1 mg.kg-1.min-1, for 10 min were measured in dogs anesthetized with 1% halothane in oxygen. Dogs were studied twice with an interval of 1 week in a cross-over study, and were assigned to one of two groups that received saline or L-NNA intravenously in group 1 (n = 8), or L-NNA or L-NNA + L-arginine which reverses the nitric oxide synthesis inhibitor effect of L-NNA, intravenously in group 2 (n = 8) prior to lidocaine infusion. The free serum concentration of and protein-binding ratio for lidocaine were measured.

RESULTS

With saline pretreatment in group 1, lidocaine infusion significantly decreased cardiac index (CI) and significantly increased mean pulmonary arterial pressure (MPAP), pulmonary arterial occlusion pressure (PAOP), systemic vascular resistance (SVR) and pulmonary vascular resistance (PVR). L-NNA pre-treatment in group 1 significantly enhanced the changes in CI, MPAP, PAOP, SVR and PVR during lidocaine infusion. In group 2, L-arginine infusion partially offset the additive effects of L-NNA to the depressive effects of lidocaine. There were no significant differences in free serum concentration of or protein-binding ratio for lidocaine among the groups.

CONCLUSION

In contrast to in vitro study, vasoconstrictor effect of lidocaine is enhanced when a capacity for compensatory vasodilation including EDRF/NO pathway is exhausted in halothane-anesthetized dogs.

Cyclothialidine analogs, novel DNA gyrase inhibitors

DNA gyrase inhibitors, cyclothialidines B, C, D and E were isolated from four Streptomycete strains (NR 0659, NR 0660, NR 0661 and NR 0662). Their structures have been elucidated based on the amino acid analysis of the hydrolysates, NMR and HRFAB-MS experiments and shown to be cyclothialidine analogs. The absolute stereochemistry has been determined by the chiral HPLC analysis of the hydrolysates. Cyclothialidines B, D and E are novel and potent inhibitors of DNA gyrase.

[Two cases of crush syndrome associated with intractable pain]

We describe two patients (a 21-year-old woman and a 26-year-old man) with crush syndrome who were injured by being buried under collapsed buildings in the Kobe-Awaji Earthquake, and thereafter developed severe pain in the affected limbs. On arrival at our ICU 3 days after the injury, sensation and muscular power were completely absent in both patients. Emergent fasciotomy was performed for the woman. In both patients, burning pain and allodynia occurred in the affected legs between 1 and 3 weeks following the injury while sensation and muscular power partially recovered over the same time period. Pain was not effectively controlled by oral or intramuscular analgesics. Continuous epidural analgesia with 0.25% bupivacaine at a rate of 2 ml.h-1 was effective for relieving pain in the woman, but was not effective in the man, for whom supplemental analgesics, transcutaneous nerve stimulation and near infrared radiation were required to relieve pain. We conclude that persistent pain is one of the important complications of crush syndrome, and that early treatment of pain including epidural analgesia is necessary and may improve functional prognosis of affected patients.

Administration of epidural bupivacaine combined with epidural morphine after esophageal surgery

BACKGROUND

Early tracheal extubation after esophagectomy has been postulated to reduce both morbidity rate and the cost of esophageal surgery. The purpose of this study was to determine the effect of epidural bupivacaine combined with morphine on extubation time, postoperative analgesia, respiration, and hemodynamics in patients undergoing esophagectomy.

METHODS

In a randomized double-blind study, twenty patients undergoing esophageal cancer surgery with a thoracoabdominal procedure were studied. All patients received epidural morphine 2 mg at T6-7 and 2 mg at L3-4 at the beginning of wound closure. Then 3 ml/hr continuous epidural administration of either 0.25% bupivacaine (group Bup, 10 patients) or normal saline solution (group NS, 10 patients) through the catheter inserted at T6-7 was continued for 16 hours, followed by low-dose epidural buprenorphine-bupivacaine.

RESULTS

The time from end of operation to tracheal extubation was 4.4 +/- 6.7 hours in group Bup and 13.7 +/- 7.1 hours in group NS (p < 0.05). All patients in both groups obtained moderate or adequate pain relief (visual analog scale of 21 +/- 27 mm) without serious side effects. There were no significant differences in visual analog scale, score for pain on a deep breath, blood pressure, heart rate, or respiratory rate between the two groups.

CONCLUSIONS

Continuous administration of epidural bupivacaine combined with morphine resulted in good analgesia without any respiratory or hemodynamic depression in patients who had undergone esophagectomy, and early extubation is related to the efficacy of continuous epidural administration of bupivacaine.

[An experience with omentopexy for the repair of postoperative bronchopleural fistula]

Postoperative bronchopleural fistula has been the most troublesome complications in the thoracic surgery. In this report, we presented a case of bronchopleural fistula successfully closed by omentopexy. A 51-year-old man had undergone left upper lobectomy and S6 segmentectomy for primary lung cancer. Bronchopleural fistula due to postoperative pneumonia was developed and completion pneumonectomy with the intercostal-musclo-pexy was performed. Post-re-operative course was unsuccessful, bronchopleural fistula remained, so we tried re-closure of the bronchial stump by omentopexy without thoracoplasty or muscle flap plombage. About a half year after 3rd operation, he relapsed into bronchopleural fistula. Then fibrin gluing was performed via a flexible fiberoptic bronchoscope without hospitalization, and the omental flap was fixed completely to the bronchial stump. We believe the omentopexy a useful procedure for treating postoperative bronchopleural fistula which can't make any chest-wall deformation.

Effect of phenobarbital on the pharmacokinetics of lidocaine, monoethylglycinexylidide and 3-hydroxylidocaine in the rat: correlation with P450 isoform levels

To elucidate the effect of cytochrome P450 levels in hepatic microsomes on the metabolism of lidocaine in vivo, we investigated the metabolism of lidocaine in untreated (UT group) and phenobarbital-treated rats (PB group) in vivo and compared the results with those obtained by immunoblotting of rat hepatic microsomes. There were no differences in pharmacokinetic parameters for lidocaine between the UT and PB groups. The plasma concentrations of the N-deethylated metabolite of lidocaine, monoethyl-glycinexylidide (MEGX), in the PB group were significantly higher than those in the UT group. On the other hand, the plasma concentrations of the aromatic ring hydroxylated metabolite of lidocaine, 3-hydroxylidocaine (3-OH LID), were significantly lower in the PB group than in the UT group. When lidocaine metabolism was studied with hepatic microsomes prepared from rats in the UT and PB groups, the rates of formation of MEGX were higher in the microsomes of the PB group than in those of the UT group. The contents of CYP2B1 and 3A2 in rat hepatic microsomes of the BP group measured by immunoblotting were significantly higher than those of the UT group. Strong correlations were found between the area under the plasma concentration vs. time curve for MEGX and specific contents of CYP2B1 and 3A2. These findings suggest that formation of MEGX in vivo is dependent on the levels of CYP2B1 or 3A2 in rat liver.

[The effects of vasoconstrictors on distribution of ischemic tissue flow in isolated perfused rat liver]

We studied the effects of ATP and epinephrine on distribution of ischemic hepatic tissue flow in the isolated perfused rat liver. Five minutes after clamping both the portal vein and hepatic artery, perfusion was started. Lidocaine was infused into the portal vein, and the concentration of lidocaine in hepatic outflow was measured with FPIA. The oxygen extraction ratio was also measured. Tissue surface blood flow was measured with laser-Doppler flowmetry. We measured the tissue flow at 2 points: one where flow was more than 10 ml.min-1.100 gm liver weight-1 (R), and the other where flow was less than 10 ml.min-1.100 gm liver weight-1 (P). After perfusion pressure had become stable, ATP or epinephrine was infused for 15 minutes. Perfusion pressure increased, and tissue flow of R decreased significantly, while that of P increased (not significantly). The extraction ratio of lidocaine decreased significantly by epinephrine, and that of oxygen decreased (not significantly). We conclude that in the ischemic liver, vasoconstriction results in changes in the distribution of tissue blood flow and alters drug metabolism.

Intraoperative continuous epidural lidocaine for early postoperative analgesia

We determined the early postoperative analgesia using intraoperative continuous epidural infusion of lidocaine during general anesthesia in patients undergoing upper abdominal surgery in a prospective double-blind manner. After insertion of an epidural catheter at the T10-T11 interspace, general anesthesia was induced. Thirty patients were randomly allocated to receive continuous epidural infusion of either 0.5% (n = 15) or 1% (n = 15) plain lidocaine at 10 ml/hr. The infusion was continued from 10 to 15 minutes before surgery until the end of surgery. Visual analog pain scale (0-10) within 30 minutes after the end of surgery was significantly lower in the 1% lidocaine group (5.6 +/- 0.9, mean +/-SE) than in the 0.5% lidocaine group (8.2 +/- 0.8), however, it was unsatisfactory in both groups. Plasma concentrations of lidocaine and its principal metabolite, monoethylglycinexylidide, gradually increased through epidural infusion, but remained below the toxic range in both groups. We conclude that continuous epidural lidocaine during general anesthesia offered limited analgesia in the early postoperative period.