The effect of carvacrol on muscarinic receptors of guinea‐pig tracheal chains

The effects of three concentrations of carvacrol, the constituent of Zataria multiflora Boiss (a monoterpenoid phenol, C₁₀H₁₄O) and 10 nm atropine on muscarinic receptors were tested on: non‐incubated (n = 7), incubated tracheal chains with propranolol and chlorpheniramine (n = 6) and incubated with propranolol (n = 5). The EC₅₀ of all three concentrations of carvacrol in incubated tissues with propranolol and chlorpheniramine was significantly greater than those of incubated tissues with propranolol and non‐incubated trachea (p < 0.05 to p < 0.001). The EC₅₀ of two higher concentrations of carvacrol (0.2 and 0.4 µg/mL) in incubated tissues with propranolol was also significantly greater than those of non‐incubated trachea (p < 0.01 to p < 0.001). The maximum response in the presence of all concentrations of carvacrol in non‐incubated and incubated tissues with propranolol and chlorpheniramine and those of its two higher concentrations (0.2 and 0.4 µg/mL) in incubated tissues with propranolol were lower than saline (p < 0.05 to p < 0.001). There were parallel rightward shifts in the concentration–response curves in the presence of all concentrations of carvacrol in non‐incubated and incubated tissues with propranolol and its lower concentration in incubated tissues with propranolol and chlorpheniramine. These results indicated an inhibitory effect of carvacrol on muscarinic receptors. A β‐adrenoceptor stimulatory effect was also suggested for carvacrol. Copyright © 2010 John Wiley & Sons, Ltd.     

气管插管术在238例患者中的应用及护理干预

目的分析紧急气管插管术成功的方式方法。方法对我院2007年8月至2008年8月实施238例紧急气管插管术的回顾分析。结果238例中无需药物诱导直接气管插管54例,快速静推地西泮诱导后气管插管184例。经口气管插管195例,经鼻气管插管43例。总插管成功236例,成功率99.4%。一次插管成功220例,成功率94.5%。插管失败2例,失败率0.6%。并发症发生率6.2%。结论提高紧急气管插管成功的关键是：制定明确的急诊插管适应证,做好各项术前准备工作,精练插管方法;选择合适的插管方式;评估气管插管困难程度,掌握气管插管的技巧,熟悉气管插管失败后的挽救措施;预防气管插管术的并发症。     

125Ⅰ粒子植入对家兔气管辐射损伤的实验观察

目的:研究植入125I粒子后家兔气管组织结构的辐射损伤,探讨临床应用安全性.方法:采用2x2析因设计方法,将实验组和空白对照组动物在不同时间点(第14天,第30天)的损伤程度进行组合交叉分组,研究辐射和时间两种因素各自损伤水平,以及两者间有无交互作用.具体分组方法如下:健康雄性普通级新两兰家兔16只(体重2.5～3.0 kg)按照体重与窝别配为8对,再随机分为2个亚组(第14天组,第30天组),每组4对;每对动物各自分为实验组1只,对照组1只.实验组(8只)采取气管外膜缝扎3颗0.5 mCi125I粒子,粒子互相间隔10 mm排列的布源方法,对照组(8只)采用3颗空白粒子,按相同方法布源.第14天与第30天分别取相应亚组动物气管进行肉眼观察、HE染色病理与透射电镜检查,观察炎症损伤程度,进行统计分析.结果:第14天和第30天,实验组和对照组兔左侧气管均无穿孔、血栓形成等严重并发症;两组HE染色对比炎症损伤程度计分无显著性差异(P>0.05);实验组电镜观察到辐射敏感细胞器损伤,但第14天与第30天无明显程度差异,对照组电镜检查正常.结论:间隔10 mm连续排列的3颗0.5 mCi125I粒子对家兔气管的辐射损伤小,临床应用安全.     

Tracheal chondrosarcoma

Tracheal chondrosarcomas are rare, with only 14 cases previously documented. We report a case of chondrosarcoma of the trachea and review other published cases. Our patient was a 34-year-old man who began to feel shortness of breath 8 months after initial hemoptysis. Transverse and coronal computed tomography demonstrated a tumor that was obstructing nearly 80% of the tracheal lumen at the thoracic inlet. A bronchoscopic biopsy specimen led to an initial diagnosis of chondroma. Five tracheal rings from the third to the seventh including the tumor were completely resected, and an end-to-end anastomosis was performed. The histological diagnosis of the surgical specimen showed it to be a chondrosarcoma. The patient was alive without recurrence at 6 years 4 months after surgery. Because recurrence after incomplete resection and malignant transformation can occur with chondromas, radical resection of the trachea is recommended for all cartilaginous tumors of the trachea.     

Evaluation of cuffed tracheal tube size predicted using the Khine formula in children

BACKGROUND: The correct size of cuffed endotracheal tube (CET) limits the risk of postintubation tracheal damage. The aim of this study was to compare the size of the CET used in children with the size predicted by the Khine formula [age (years)/4 + 3]. METHODS: After ethical committee approval, 204 children aged 1 day-15 years were included prospectively in the study. The choice of the size of the CET was made at the discretion of the attending anesthesiologist. The main criterion of judgment was the comparison of the leak before and after inflating the cuff at a pressure of 20 cm.H(2)O. Demographic data, tracheal tube size used and that predicted by Khine's formulae and side-effects were recorded. RESULTS: Overall, 21% of the CET were in accordance with the size predicted by the Khine formula. In the remaining patients, 72% were oversized and 7% undersized. In 12 cases, the size of CET chosen initially was modified: for a larger size in eight children and for a smaller size in four others. Six children (2.9%) presented with minor postoperative complications. CONCLUSIONS: Our data suggest that Khine's formula for predicting the appropriate tracheal tube size underestimates optimal size by 0.5 mm. We therefore recommend the use of the following formula: internal diameter of the CET = [age/4 + 3.5] in children >1 year of age which may be applied without increased risk of complications. The rate of tracheal reintubation as well as the detected leaks supports these recommendations.     

Role of carbon monoxide in electrically induced non-adrenergic, non-cholinergic relaxations in the guinea-pig isolated whole trachea

BACKGROUND AND PURPOSE: Nitric oxide (NO) and vasoactive intestinal peptide (VIP) are considered transmitters of non-adrenergic, non-cholinergic (NANC) relaxations in guinea-pig trachea, whereas the role of carbon monoxide (CO) is unknown. This study was designed to assess the participation of CO, and to investigate the localization of haem oxygenase-2 (HO-2), the CO-producing enzyme, in tracheal neurons. EXPERIMENTAL APPROACH: NANC responses to electrical field stimulation (EFS) at 3 and 10 Hz were evaluated in epithelium-free whole tracheal segments as intraluminal pressure changes. Drugs used were: L-nitroarginine methyl ester (L-NAME, 100 microM) to inhibit NO synthase (NOS), alpha-chymotrypsin (2 U ml(-1)) to inactivate VIP, zinc protoporphyrin-IX (ZnPP-IX, 10 microM) to inhibit HO-2, and 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 10 microM), a soluble guanylyl cyclase inhibitor. For immunohistochemistry, tissues were exposed to antibodies to PGP 9.5, a general neuronal marker, HO-2 and NOS, and processed with an indirect immunofluorescence method.Key results:alpha-Chymotrypsin did not affect NANC relaxations. ODQ inhibited NANC responses by about 60%, a value similar to that obtained by combining L-NAME and ZnPP-IX. The combination of ODQ, L-NAME and ZnPP-IX reduced the responses by 90%. Subpopulations of HO-2 positive neurons containing NOS were detected in tracheal sections. CONCLUSIONS AND IMPLICATIONS: In the guinea-pig trachea, NANC inhibitory responses at 3 and 10 Hz use NO and CO as main transmitters. Their participation is revealed following inhibition of NOS, HO-2 and soluble guanylyl cyclase. The involvement of CO as a relaxing transmitter paves the way for novel therapeutic approaches in the treatment of airway obstruction.     

颈段气管袖状切除术的临床分析

目的：总结颈段气管袖状切除术的经验，以提高颈段气管肿瘤的治疗效果。方法：回顾性分析1985-01～2006—12颈段气管袖状切除术治疗的12例患者，其中腺样囊性癌6例，鳞状细胞癌4例，腺癌1例，颈段气管软化塌陷1例。气管切除长度3～6cm，其中气管切除长度≥5cm5例，喉体松解术7例，甲状腺次全切除术3例。用正常甲状腺组织包绕气管及吻合口9例，未包绕3例。结果：所有患者喉功能均得以保留，发声正常，吻合口生长良好，受到分离的气管段色泽红润。3年生存率为85．37％，5年生存率为56．61％。结论：颈段气管袖状切除术符合气管肿瘤的治疗原则。改进的术式有利于气管吻合口的愈合，有利于更干净、彻底地切除气管肿瘤。     

Pulsating Suprasternal Lump: A Diagnostic and Management Dilemma

We report a 70-year-old female who complained of shortness of breath and a pulsating suprasternal lump. CT scan showed innominate artery dilatation. In addition, operative exposure showed tortuous arteries and a common origin of the left common carotid and innominate arteries. Surgical correction by innominate artery division and reimplantation at the ascending aorta was performed, and the patient’s symptoms completely disappeared after the procedure.     

预防性气管插管在急性中毒病人中的应用研究

目的：评价预防性气管插管在危重中毒病人洗胃时的疗效和价值。方法：140例危重中毒患采用预防性气管插管后洗胃，与100例未采用预防性气管插管洗胃的中毒病人进行对比。结果：采用预防性气管插管的140例危重中毒患均成功洗胃，而未采用预防性气管插管洗胃的100例危重中毒患中，有24例未成功洗胃，有13例死亡，死亡率为13％。结论：对重度中毒患应采用预防性气管插管后洗胃，可减少死亡率。     

蛋白激酶C激动剂PMA、阻滞剂H-7及氯胺酮、咪唑安定对兔离体气管平滑肌收缩力的影响

目的：探讨蛋白激酶Ｃ（ＰＫＣ）信号传导系统在气管平滑肌张力调节中的作用及氯胺酮、咪唑安定对其的影响。方法：研究不同浓度的ＰＫＣ激动剂ＰＭＡ（３×１０－７～３×１０－５ｍｏｌ／Ｌ）对静息状态下气管平滑肌张力的影响；研究两种浓度的ＰＭＡ（３×１０－６，３×１０－５ｍｏｌ／Ｌ）及特异性ＰＫＣ阻滞剂Ｈ－７（３×１０－５ｍｏｌ／Ｌ）对乙酰胆碱（１０－４ｍｏｌ／Ｌ）诱发气管平滑肌收缩力的调节作用及Ｈ－７、氯胺酮、咪唑安定对ＰＭＡ效应的抑制作用。结果：３×１０－７～３×１０－５ｍｏｌ／Ｌ的ＰＭＡ对静息状态下的气管平滑肌张力无明显影响，３×１０－６ｍｏｌ／Ｌ的ＰＭＡ可明显增强乙酰胆碱诱发张力的峰值和平台值，然而３×１０－５ｍｏｌ／Ｌ的ＰＭＡ并不能进一步增加乙酰胆碱的作用，张力平台值有所下降；３×１０－５ｍｏｌ／Ｌ的Ｈ－７可完全抵消３×１０－６ｍｏｌ／Ｌ的ＰＭＡ效应。１０－３ｍｏｌ／Ｌ氯胺酮和１０－４ｍｏｌ／Ｌ咪唑安定和Ｈ－７有相似的效果。结论：ＰＫＣ信号传导系统的激活并不能单独诱发离体气管平滑肌的收缩，但可使乙酰胆碱的收缩效应增加，氯胺酮和咪唑安定对ＰＫＣ信号传导系统有抑制作用。