[Use of StyletScope in a patient with airway injury].

A forty-year old man hanged himself and was transported to our hospital. On arrival his consciousness was clear but he showed dyspnea, dysphagia, and oral bleeding. Tracheal intubation was attempted but was failed and emergency tracheostomy was successfully accomplished. Tracheoplasty was soon scheduled under general anesthesia because of subcutaneous emphysema. An ordinary laryngoscope could not give a view of the larynx at all. Orotracheal intubation was accomplished with StyletScope. It worked very well for the destroyed trachea. StyletScope is a useful device for intubation, especially in difficult airway management.

Effect of carvedilol on heart failure in patients with a functionally univentricular heart.

BACKGROUND: The effect of carvedilol on heart failure (HF) in patients with a functionally univentricular heart (UVH) remains unclear. METHODS AND RESULTS: Carvedilol was used to treat HF in 51 patients with a UVH, classified into 3 groups: after the Fontan operation (F), after the bidirectional Glenn operation (G), and patients who had not undergone Fontan or Glenn operation (NF). Carvedilol therapy was started at a mean age of 10 ± 12 years (range: 1 month to 34 years). The initial and maximum doses of carvedilol were 0.04 ± 0.03 and 0.42 ± 0.29 mg · kg(-1) · day(-1), respectively. After a mean follow-up of 11 months, the cardiothoracic ratio improved from 60 ± 8 to 58 ± 8% (P<0.01), and the dosage of furosemide was reduced from 1.4 ± 0.9 to 0.7 ± 0.7 mg · kg(-1) · day(-1) (P < 0.01). The ejection fraction also improved from 35 ± 12 to 40 ± 11% (P < 0.05), and this improvement was prominent in the F group (from 35 ± 15 to 45 ± 9%; P < 0.05). Clinical signs, symptoms, and New York Heart Association functional class also improved. CONCLUSIONS: Carvedilol may play an important role in treating HF associated with a UVH.

Molecular dynamics simulation of the formation of sp3 hybridized bonds in hydrogenated diamondlike carbon deposition processes.

The formation process of sp3 hybridized carbon networks (i.e., diamondlike structures) in hydrogenated diamondlike carbon (DLC) films has been studied with the use of molecular-dynamics simulations. The processes simulated in this study are injections of hydrocarbon (CH3 and CH) beams into amorphous carbon (a-C) substrates. It has been shown that diamondlike sp3 structures are formed predominantly at a subsurface level when the beam energy is relatively high, as in the "subplantation" process for hydrogen-free DLC deposition. However, for hydrogenated DLC deposition, the presence of abundant hydrogen at subsurface levels, together with thermal spikes caused by energetic ion injections, substantially enhances the formation of carbon-to-carbon sp3 bonds. Therefore, the sp3 bond formation process for hydrogenated DLC films essentially differs from that for hydrogen-free DLC films.

Efficacy and safety of carvedilol for heart failure in children and patients with congenital heart disease.

There have been few reports describing the use of carvedilol in children or patients with congenital heart disease. Therefore, its optimal regimen, efficacy, and safety in these patients have not been adequately investigated. Subjects were 27 patients with two functioning ventricles, for whom carvedilol was initiated (from December 2001 to December 2005) to treat heart failure. All patients had failed to respond to conventional cardiac medication. They consisted of 12 males and 15 females, aged 23 days to 47 years (median age: 2 years). Heart failure due to ischemia (myocardial infarction, intraoperative ischemic event) or due to myocardial disease (cardiomyopathy, myocarditis), and heart failure with atrial or ventricular tachyarrhythmia represented 70% of all cases. Carvedilol was initiated at a dose of 0.02-0.05 mg/kg/day, which was increased by 0.05-0.1 mg/kg/day after 2 days, 0.1 mg/kg/day after 5 days, and 0.05-0.1 mg/kg/day every month thereafter with a target dose of 0.8 mg/kg/day. This study retrospectively assessed the efficacy and adverse reactions based on changes of symptoms, cardiothoracic ratio (CTR), left ventricular ejection fraction (LVEF), and human atrial natriuretic peptide (hANP)/b-type natriuretic peptide (BNP) blood levels. The mean follow-up period was 10.2 months (range: 1-46 months). Twenty-six (96.3%) patients showed improvement in symptoms and were discharged from the hospital. However, the remaining one patient failed to respond and died. Significant cardiovascular adverse reaction was seen in none of the patients. The mean CTR decreased from 61.8% +/- 5.3% before treatment to 57.6% +/- 7.4% after treatment (P < 0.05, n = 25), and the mean LVEF improved from 41.4% +/- 23.1% to 61.1% +/- 10.1% (P < 0.05, n = 10), respectively. Mean hANP and BNP levels showed a decrease from 239.1 pg/ml to 118.3 pg/ml and a significant decrease from 437.9 pg/ml to 120.5 pg/ml, respectively (P < 0.05, n = 10). Improvements in these data were also demonstrated when analyzed individually among the pediatric group (aged younger than 18) and the congenital heart disease group. Initiation of carvedilol at a lower dose with more gradual dose escalation, compared with previously reported regimens, might have efficacy with low incidence of adverse effects in pediatric patients and patients with congenital heart disease. Carvedilol may be effective in treating heart failure in children due to ischemia, myocardial disease, and complicated by tachyarrhythmia.

[Perception of dyspnea due to breath-holding in myotonic dystrophy].

Patients with myotonic dystrophy (DM1) rarely complain of dyspnea despite of severe hypoxemia. We studied the perception of dyspnea caused by breath-holding in 9 DM1 patients and 8 healthy control subjects. The patients, as well as the control subjects, complained of dyspnea and showed decrease in SpO2. In none of the patients but one, however, the bottom SpO2 became lower than the minimal SpO2 recorded in 24-hour monitoring. DM1 patients were able to realize hypoxia caused by apnea, although they had not realized hypoxia that already existed. Consequently, the breath-holding test does not uncover a blunted perception of dyspnea in DM1; an afferent system contributable to air hunger sensation in breath-holding is preserved in DM1. Breath-holding test may be useful for a DM1 patient to recognize the significance of sleep apnea.

A case of amusia caused by the infarction of anterior portion of bilateral temporal lobes.

It remains an unsettled question which brain regions participate in music perception. During singing a familiar song, the retrieval from long-term memory is necessary, but the mechanism of that retrieval is still unclear. We carried out a detailed examination of musical ability in a patient with amusia and control subjects and identified the lesion sites of our patient using MRI. Compared with controls, the patient manifested the following impairments in music perception: (i) the recognition and discrimination of familiar melodies; (ii) the discrimination of unfamiliar phrases; (iii) the discrimination of isolated chords. During singing familiar nursery songs, the patient showed the replacement of one phrase of the melody. In MRI, the patient had old infarction in the anterior portion of the temporal lobes bilaterally. In conclusion, the anterior temporal lobes participate in the perception and expression of music. During singing, the song is retrieved from long-term memory by a unit of one phrase. The dysfunction of that retrieval caused the replacement of the succeeding phrases of the original with the wrong tune, and we named this phenomenon paramelodia.

[Propofol suppresses the responses in hypoglossal nerve activity to hypercapnic-hypoxic stimulation].

BACKGROUND: Upper airway obstruction and inadequate ventilation often arise during sedation and anesthesia by propofol. To estimate the influence of propofol (PP) on respiratory control, we studied its effect on the neural activity and the respiratory response caused by a brief (60 sec) respiratory arrest (RA) manifesting in the hypoglossal nerve (HG) and the phrenic nerve (PN) in rabbits. METHODS: Experiments were performed on adult rabbits vagotomized, paralyzed and ventilated artificially with 50% N2O, 50% oxygen and 0.5% sevoflurane. We evaluated and compared the effects of PP on the peak amplitude (AMP) and the root mean square (RMS) of HG and PH, and respiratory cycle (Tc). RESULTS: PP depressed HG activity more than PH activity, and increased Tc in a dose related manner, with 0.25 mg x kg(-1) x min(-1) continuous infusion, propofol soon began to reduce both AMPs without any remarkable changing in Tc. AMP&RMS-HG were reduced to about 35% and AMP&RMS-PN to 80% of control. Administration of propofol 1.5 mg x kg(-1) x min(-1) vanished the activity of HG in all animals. RA made a mixed hypercapnic and hypoxic condition and induced RA response which was characterized by raised AMPs, augmented RMSs (deltaAMPs, deltaRMSs) in activity of both nerves activity and lengthened Tc (deltaTc). PP depressed RA response in HG dose-dependently, but did not do so in PN. Significant depressions in cardiovascular effects with tested dosage of PP occurred, but the values were kept in physiological ranges. CONCLUSIONS: These results suggest that propofol induces respiratory depression by its inhibitory effect on the neural regulation of respiration, especially on the maintenance system of upper airway patency and the reflex related to the chemosensitive upper airway patency control.

[A case of cardiac myxoma presenting with multiple cerebellar hemorrhages and elevation of interleukin-6 in the cerebrospinal fluid].

We report a 25-year old man with cardiac myxoma presenting with multiple cerebellar hemorrhages and elevation of interleukin-6 (IL-6) in the cerebrospinal fluid (CSF). The patient was first admitted to our hospital because of cerebral infarctions at the age of 23. After systemic exploration he was diagnosed as cardiac myxoma. In this patient, the serum level of IL-6 was elevated. The cardiac myxoma was resected and the serum IL-6 level returned to normal. His neurological symptoms improved almost to normal and he was discharged. The patient had been well for two years until he developed headache at the age of 25. Brain MRI revealed multiple cerebellar hemorrhages that overlaid old infarctions. The hemorrhages enlarged in a three months period and his headache became worse, and then he was admitted again. The IL-6 value was normal in serum at that time, but it was elevated in the CSF. The CSF IgG index was also elevated. Cerebral angiograms showed no abnormal vessel in the infratentorium, while multiple fusiform aneurysms were found in both middle cerebral arteries. A transesophageal echocardiography revealed no recurrence of cardiac myxoma. Craniotomy was performed and intracerebellar hematomas were removed. Histopathological examination showed only old and recent bleedings; no metastatic myxoma tissue was found. Although no myxoma tissue was found in biopsy specimen, it seemed reasonable that an elevated level of IL-6 in the CSF was due to metastasized intracranial myxoma, which caused cerebellar embolism, and then invaded the vessel walls and continued to grow. In reviewing the literature we have found no reported case of cardiac myxoma with analysis of IL-6 value in the CSF. We speculate that the level of IL-6 in the CSF might be a good marker for the neurological manifestations of cardiac myxoma.

[Effect of flumazenil on hypoglossal and phrenic nerves activities in rabbits].

BACKGROUND: Upper airway obstruction and inadequate ventilation often arise during sedation and anesthesia by benzodiazepines (Bz). Flumazenil antagonizes these effects of active benzodiazepines on the central nervous system. To estimate the influence of flumazenil on the endogenous Bz system related respiratory control, we studied the effect of flumazenil and diazepam on the neural activity and the respiratory response caused by a brief (60 sec) respiratory arrest (RA) manifested in the hypoglossal nerve (HG) and the phrenic nerve (PH) activities in rabbits. METHODS: Experiments were performed on adult rabbits which were vagotomized, paralyzed and artificially ventilated with 50% N2O, 50% oxygen and 0.5% sevoflurane. We evaluated and compared the effects of the sequential administrations of flumazenil and diazepam on the peak amplitude (AMP) as well as the root mean square (RMS) of HG and PH, and respiratory cycle (Tc). RESULTS: Flumazenil by itself increased HG activity more than PH activity with no influence on Tc. But it was not dose-related. Previous administration of flumazenil in total dose of 0.25 mg x kg(-1) could not prevent the anticipated respiratory depression caused by diazepam 2.0 mg x kg(-1). These depressions are greater in HG activity than in PH activity. Additional flumazenil 0.15 mg x kg(-1) following the administration of diazepam promptly reversed these inhibitory effects on HG activity beyond the control level. The same dose of flumazenil, however, did not reverse PH activity sufficiently. RA response was characterized by raised AMPs and augmented RMSs (deltaAMPs, deltaRMSs) with marked prolongation in Tc (deltaTc). Flumazenil and diazepam did not seem to have any influence upon these RA responses. There was a significant change in cardiovascular parameters with the tested dosages of flumazenil and diazepam, but the change was in the normal physiological range. CONCLUSIONS: These results suggest the possibility that the endogenous benzodiazepine system is likely to play an inhibitory role in the regulation of respiration, especially in the maintenance of upper airway patency but the system is unrelated to the chemosensitive-respiratory control.

Pathological lesions causing pulmonary hypertension after closure of a ventricular septal defect.

A 15-year-old boy with a ventricular septal defect, pulmonary hypertension, Down's syndrome, and extremely thickened media (ETM) of the small pulmonary arteries died of heart failure and pulmonary hypertension 13 years after intracardiac repair. Microscopic examination of lung specimens collected prior to the intracardiac repair and at the time of autopsy revealed that the ETM had remained unchanged and that the arteries connected to the vessels with ETM had become severely thickened. The present case shows that even a small percentage of arteries with ETM can cause pulmonary hypertension, and illustrates one of the mechanisms of how pulmonary hypertension can fail to be resolved after intracardiac repair.

[Propofol depresses the activity of hypoglossal nerve more than that of phrenic nerve in rabbits].

BACKGROUND: Respiratory depression, such as obstruction of upper airway and inadequate ventilation, often appears during sedation and anesthesia. We studied the effect of propofol on the upper airway patency and the inspiratory drives. METHODS: Experiments were performed on the adult rabbits vagotomized, paralyzed and ventilated with nitrous oxide-oxygen-sevoflurane. We evaluated and compared depressant effect of propofol on the peak amplitude of both hypoglossal nerve (AMP-HG) and phrenic nerve (AMP-PH) activities, inspiratory time (Ti), expiratory time (Te) and respiratory cycle (Tc). RESULTS: Bolus injections of propofol transiently reduced AMP-HG more than AMP-PH (18 and 70% of control, respectively). But AMPs returned to the control levels about 10-15 min after the injection. For 0.5 mg.kg-1.min-1 continuous infusion, propofol soon began to reduce both AMPs. AMP-HG was reduced to about 20% and AMP-PH to 60% of control. Administration of propofol with 1.0 mg.kg-1.min-1 caused more reduction in AMPs with respiratory slowing and AMP-HG disappeared in some animals. CONCLUSION: During the sedation with low dose of propofol, we need to pay attention to potential upper airway obstruction. In addition to the above, high doses of propofol could reduce spontaneous inspiratory drive, and we need to keep both upper airway patency and sufficient ventilation.

[How do diazepam and flumazenil influence respiratory control by the activities of both hypoglossal and phrenic nerves in rabbits?].

BACKGROUND: Upper airway obstruction and inadequate ventilation often arise during sedation and anesthesia by benzodiazepines. To estimate the influence of benzodiazepines on the respiratory control, we studied the effect of diazepam and flumazenil on the neural activity and the respiratory response caused by a brief (60 sec) respiratory arrest (RA) observed in the hypoglossal nerve (HG) and phrenic nerve (PH) in rabbits. METHODS: Experiments were preformed on adult rabbits vagotomized, paralyzed and ventilated artificially with 50% N2O, 50% oxygen and 0.3-0.5% sevoflurane. We evaluated and compared the effects of diazepam and flumazenil on the peak amplitude (AMP-HG&PH) and the root mean square (RMS-HG&PH) of HG and PH, and respiratory cycle (Tc). RESULTS: Diazepam depressed HG activity more than PH activity with no influence on Tc. But it did not cause dose-related depression. Flumazenil 0.2 mg.kg-1 completely reversed the respiratory depressions caused by diazepam with the increased Tc. In addition to augmentation of the hypoglossal activity in inspiration, flumazenil caused a rise in its activity in pan-expiratory period in some cases. Additional administration of diazepam 6 mg.kg-1 following flumazenil depressed PH activity again, but did not affect HG activity any more. There was no significant depression in cardiovascular parameters with tested dosages of diazepam and flumazenil. RA response was characterized by raised AMPs and augmented RMSs (delta AMPs, delta RMSs) with marked prolongation in Tc (delta Tc). Diazepam depressed RA response dose dependently, but flumazenil did not seem to antagonize this depression. CONCLUSIONS: These results suggest that 1) flumazenil is not only a specific antagonist of benzodiazepines but also a potential excitatory agent of hypoglossal nerve activity, and that 2) there is some functional diversity in disposition of benzodiazepine-receptor binding GABAA-receptor responsible for neural respiratory control system.

Monostotic fronto-orbital fibrous dysplasia with convulsion--case report.

A 28-year-old man presented with monostotic fronto-orbital fibrous dysplasia associated with convulsions. Signs of meningeal irritation were observed. Computed tomography (CT) showed right frontal sinusitis, and destruction from the inner to outer table with expansion of the diploic space. T1- and T2-weighted magnetic resonance imaging showed an abnormal low-intensity mass, with heterogeneous gadolinium enhancement. Although the meningitis resolved, signs of infection continued for 2 months due to sinusitis. Treatment of the right frontal sinusitis was undertaken, accompanied by open biopsy. The histological diagnosis was fibrous dysplasia. Once the infection had completely resolved, orbitofrontal reconstruction was undertaken. Cranioplasty was carried out using cranial bone cement. Three-dimensional CT was valuable to show the likely postoperative result.