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41.
IntroductionLeiomyosarcoma is a rare mesenchymal tumor that originates from smooth muscle cells. Head and neck LMSs represent only 3% of all leiomyosarcomas with less than 50 cases of laryngeal LMS reported in the literature till now.Case presentationWe report a case of 50-year-old male presented at our ENT department for a chronic hoarseness. Clinical examination investigations found small submucosal lesion in the right vocal cord. Treatment consisted of CO2 Laser excision of the lesion. The evolution was marked by the appearance of a tumefaction in the left submandibular region and a severe dyspnea requiring an emergency tracheotomy. Paraclinical examination investigations found a supraglottis–glottis-subglottis tumor. A total laryngectomy with bilateral functional neck dissection was performed and the histopathological examination found a laryngeal leiomyosarcoma.ConclusionLMS of the larynx a very rare malignancy. The accurate diagnosis is histological. Surgery is the mainstay of treatment. Its prognosis is correlated to local recurrence and distant metastases. 相似文献
42.
Twenty-five patients who required mechanical ventilatory support (MVS) after major surgery or severe burns were studied to determine whether airway occlusion pressure (P0.1) is a clinically useful indicator to predict the success or failure of the weaning trial. A total of 33 weaning trials were attempted on these patients. Of the 33 trials, 24 were followed by successful weaning and 9 by failure. Although the success group, when compared with the failure group, had a lower respiratory rate (P 0.001), a lower minute ventilation (P 0.001), a higher maximal voluntary ventilation to minute ventilation ratio (P 0.01) and a higher forced vital capacity (P 0.05), no threshold values separated the success from the failure group. The alveolar-arterial PO
2 gradient, with an Fi
O
2 of 1.0, in weaning success and failure showed no statistical difference. In contrast, all patients in the success group had a P0.1 of less than 3.5cmH2O and those in the failure group had a P0.1 of greater than 3.5cmH2O (P 0.001). We conclude that P0.1 is a clinically superior indicator for discontinuing MVS in patients with acute respiratory failure.(Okamoto K, Sato T, Morioka T: Airway occlusion pressure (P0.1)—A useful predictor for the weaning outcome in patients with acute respiratory failure—. J Anesth 4: 95–101, 1990) 相似文献
43.
激光治疗器质性呼吸道阻塞 总被引:1,自引:0,他引:1
目的 观察激光在器质性呼吸道阻塞性疾病治疗中的应用价值。方法 应用Nd :YAG激光治疗 40例器质性呼吸道阻塞患者 ,观察治疗前后患者症状、肺功能、血气分析、气道内径的改善情况及治疗的安全性。结果 应用Nd :YAG激光治疗后患者气道全部通畅 ,气道内径明显扩大 :治疗前 (2 9± 1 7)mm ,治疗后 (8 0± 1 6)mm ,P <0 0 1;气促明显缓解 :气促指数治疗前 3 2± 0 8,治疗后 1 3± 0 9,P <0 0 1;PaO2 明显升高 :治疗前 (9 4± 1 81)kPa ,治疗后 (11 6± 1 1)kPa ,P <0 0 1;FEV1明显改善 :治疗前 (1 4± 0 3 )L ,治疗后 (2 4± 0 4)L ,P <0 0 1;FVC明显增加 :治疗前 (2 3±0 7)L ,治疗后 (3 3± 0 6)L ,P <0 0 1;治疗过程中 3 2例出现一过性低氧血症 ,2例出血 ,5例术后呼吸困难 ,2例术后发热。术后随访 :17例患者术后 3~ 4个月出现气道再次狭窄 ,11例经再次激光治疗后气道再次通畅。结论 Nd :YAG激光治疗器质性呼吸道阻塞是安全有效的手段并可反复应用 ,值得临床推广使用 相似文献
44.
The purpose of this case report is to describe the events, intervention, and aetiology which led to acute airway obstruction in an adult patient after the placement of a Hickman catheter. Airway obstruction secondary to superior vena cava obstruction occurred after placement of a subclavian vein Hickman catheter. This was felt to occur, in part, to a narrowed superior vena cava as evident by subclavian venography. It resulted in emergency oral tracheal intubation to relieve airway obstruction. Shortly after removal of the Hickman catheter, the signs of superior vena cava obstruction syndrome resolved and the patient was extubated without incidence. It is concluded that, although rare, the serious complication of acute airway obstruction can occur after placement of a Hickman catheter. 相似文献
45.
D. Passàli L. Bellussi M. Lauriello D. Passali 《European archives of oto-rhino-laryngology》1995,252(6):348-352
In this paper we have analyzed the physical properties of nasal mucus from 120 outpatients with rhinitis. We focused on the most relevant rheological features: viscosity, elasticity, adhesiveness, as well as ability to be spun (spinability) or poured (pourability). A double-capillary type viscometer was used to measure viscosity and elasticity and the platinum ring method to measure adhesiveness. Spinability was measured with an automatic apparatus (Filancemetre Sefam) and pourability was determined by describing flow under gravity. Efficacy of nasal clearance was analyzed by measuring mucociliary transport time with an inert tracer using vegetal charcoal powder. Results showed that impaired nasal mucosal function in patients with rhinitis could be determined by studying rheological features in addition to measuring mucociliary activity. Information provided proved invaluable when considering possible treatment with agents affecting kinesis of nasal mucus. 相似文献
46.
Claudia Hey Ignaz Wessler Kurt Racké 《Naunyn-Schmiedeberg's archives of pharmacology》1995,351(6):651-659
Alveolar macrophages were obtained by broncho-alveolar lavage of isolated rat and rabbit lungs and cultured (2.5 × 106 cells/dish) for 18 h in the absence or presence of bacterial lipopolysaccharides (LPS) alone or in combination with cytokines. Thereafter, accumulation of 3H-citrulline (NO synthase activity) and 3H-ornithine (arginase activity) were determined.During incubation of rat alveolar macrophages with 3H-arginine clear amounts of 3H-citrulline and 3H-ornithine (3.8 and 4.6% of the added 3H-arginine, respectively) were formed and most of these metabolites appeared in the incubation medium (ratios extra-/intracellular of 17 and 70 for 3H-citrulline and 3H-ornithine, respectively). When rat alveolar macrophages had been cultured with LPS the formation of 3H-citrulline was increased about 30-fold and this was accompanied by a reduction in 3H-ornithine formation of about 60%. The effects of LPS were largely attenuated by dexamethasone (10 mol/1). Inhibition of NO synthase by NG-monomethyl-l,-arginine (l-NMMA, 100 mol/1) in LPS treated alveolar macrophages reduced the formation 3H-citrulline by more than 90% and restored the 3H-ornithine formation. After culturing in the presence of LPS the ratios extra/intracellular of 3H-citrulline and 3H-ornithine were markedly enhanced and this effect was not dexamethasone sensitive. During incubation of rabbit alveolar macrophages a marked formation of 3H-ornithine (about 5.3% of the added 3H-arginine), but no significant formation of 3H-citrulline could be detected. Pretreatment with LPS tended to enhance the formation of 3H-ornithine (by 50%) without effects on 3H-citrulline. Rabbit-interferon and/or tumor necrosis factor- present together with LPS during the culture period did not result in a significant 3H-citrulline formation. Under all conditions tested, culture media of rabbit alveolar macrophages did not contain significant amounts of nitrite (less than 0.5 nmol) whereas in culture media of untreated rat alveolar macrophages 22 nmol nitrite (per 18 h) were detected, and LPS induced a 3-fold nitrite accumulation, an effect prevented by dexamethasone.In conclusion, in rabbit alveolar macrophages NO synthase activity was not detectable and could also not be induced by LPS and different cytokines, whereas in rat alveolar macrophages NO synthase was readily inducible. Alveolar macrophages of both species showed marked arginase activity. After induction of marked NO synthase activity, ornithine formation was largely reduced possibly by concomitant inhibition of arginase and/or withdrawn of arginine from arginase. 相似文献
47.
Jose L. Ortiz José M. Vallés Miguel Martí-Cabrera Julio Cortijo Esteban J. Morcillo 《Naunyn-Schmiedeberg's archives of pharmacology》1996,353(2):200-206
There is currently interest in the potential use of selective inhibitors of cyclic nucleotide phosphodiesterases (PDE) in the treatment of asthma. In this study we examined the effects of three selective PDE inhibitors, milrinone (PDE III), rolipram (PDE IV) and zaprinast (PDE V), on the broncoconstriction produced by antigen and histamine, the airway hyperreactivity and microvascular leakage after aerosol exposure to platelet-activating factor (PAF) and antigen, and the antigen-induced eosinophil infiltration in guinea-pig lung. Inhaled rolipram (0.01–10 mg ml–1) inhibited dose dependently the bronchospasm produced by aerosol antigen (5 mg ml–1) an anaesthetised, ventilated guinea-pigs. Rolipram (10 mg ml–1) produced maximal inhibition of antigen-induced bronchoconstriction but only partial inhibition of the response to aerosol histamine (1 mg ml–1). Milrinone and zaprinast (each 10 mg ml–1) showed weak, or no, inhibitory effects against bronchoconstriction produced by aerosol antigen or histamine. Pretreatment with rolipram (10 mg kg–1, i.p.) prevented airway hyperreactivity to histamine which develops 24 h after exposure of conscious guinea-pigs to aerosol PAF (500 g ml–1) or antigen (5 mg ml–1). The pulmonary eosinophil infiltration obtained with 24 h of antigen-exposure was inhibited by rolipram. In contrast, milrinone and zaprinast (each 10 mg kg–1, i.p.) failed to reduce either the airway hyperreactivity of the eosinophil accumulation in these animals. Rolipram (1–10 mg ml–1) reduced the extravasation of Evans blue after aerosol PAF (500 g ml–1) at all airway levels while a lower dose (0.1 mg ml–1) was only effective at intrapulmonary airways. Rolipram (0.01–1 mg ml–1) markedly reduced airway extravasation produced by inhaled antigen (5 mg ml–1). Zaprinast (1–10 mg ml–1) was also effective against airway microvascular leakage produced by aerosol PAF or antigen while milrinone (10 mg ml–1) had no antiexudative effect. These data support previous suggestions that pharmacological inhibition of PDE IV results in anti-spasmogenic and anti-inflammatory effects in the airways and may be useful in the treatment of asthma. 相似文献
48.
Summary The esophageal-tracheal Combitube (Sheridan, Argyle, NY) is a new device for emergency intubation, which can be inserted blindly without the use of a laryngoscope. Ventilation is independent of the position of the Combitube in either the esophagus or the trachea, since ventilation is always provided by the tube's double channel. The tracheal channel acts as a conventional endotracheal airway and has an open distal end. The esophageal channel has a blocked distal end, so that together with the inflated distal cuff it acts as an esophageal obturator in cases of esophageal intubation. Perforations at the pharyngeal section direct the airflow to the trachea. At the oropharyngeal section a large elastic balloon is positioned in order to obturate the oral cavity and the nasopharynx. Two patients are described to exemplify the Combitube's clinical use. Both had rapidly enlarging cervical hematomas causing upper airway obstruction and thus requiring immediate intubation. Endotracheal intubation failed because the glottis could not be visualized with a laryngoscope. In both cases the Combitube was applied successfully and adequate ventilation was provided via the Combitube placed esophageally. To better secure each patient's airway, tracheotomy was performed during ventilation without any complications. 相似文献
49.
The ability of lidocaine to suppress activity of single vagal afferent fiber and that of phrenic nerve was studied in 20 cats anesthetized with pentobarbital. Slowly adapting stretch receptors (SAR, n = 16) and rapidly adapting stretch receptors (RAR, n = 7) were identified by their discharge pattern to pulmonary inflation. Intravenous lidocaine (1mg·kg–1 or 2mg·kg–1) produced a suppression of SAR activity but not of RAR activity. Suppression of phrenic nerve activity lasted much longer than that of SAR. These findings indicate that iv lidocaine acts more dominantly on CNS than on peripherals. We conclude that iv lidocaine prevents cough and hemodynamic changes caused by airway manipulation mainly through its action on CNS and not on peripherals (peripheral nerves or their receptor).(Aoki M, Harada Y, Namiki A, et al.: Effects of intravenously administered lidocaine of pulmonary vagal afferents and phrenic nerve activity in cats. J Anesth 6: 395–400, 1992) 相似文献
50.
Key words airway management - difficult intubation - Hallermann-Streiff syndrome 相似文献