The site of airway irritation during induction of anaesthesia

The aim of this investigation was to study the role of the nasal airway in mediating upper airway reflexes during induction of anaesthesia when the commonly used irritant inhalational anaesthetic agent enflurane is used. In a prospective randomised study, 40 ASA 1 & 2 day-case patients undergoing body surface surgery were recruited. Following intravenous induction using propofol, 20 patients received enflurane administered via a laryngeal mask airway (LMA), the anaesthetic vapour therefore bypassing the nasal airway. In the other group, 20 patients received enflurane anaesthesia administered using a face mask, the nasal airway therefore being exposed to inhalation anaesthetic. We were unable to demonstrate any significant (p < 0.05) differences between the two groups in relation to upper airway complications (cough, breath holding, laryngeal spasm, bronchospasm and excitement). Previous work has identified the nose as a possible important reflexogenic site for upper airway reflexes in humans during anaesthesia. We have been unable to demonstrate any difference in upper airway complications when the nasal airway was included or excluded from exposure to irritant anaesthetic vapours, when administered in a clinical setting.     

162例气管插管患者的气道管理

笔者通过报道162例气管插管患者的气道管理，阐述痰痂形成的原因：(1)气道干燥，湿化不够。(2)吸痰管插入深度不够，吸痰不彻底。管理措施：(1)用金霉素眼膏润滑吸痰管，使之易于插入，保证吸痰管插入深度超过插管远端3-5cm。(2)预防气道干燥，注重湿化效果，重视吸痰环节。认为气囊不需定时放气，只需不定时调整气囊压力。     

多层面CT重建诊断中央大气道良性病变

目的 :分析多层面CT三维重建诊断中央大气道良性病变的价值。材料和方法 :用多层面CT对 3 5例中央气道良性病变 (解剖性异常 5例 ,炎症性病变 18例及其它 12例 )扫描 ,并全部完成三维表面遮盖显示、容积显示和仿真内窥镜检查。所有病例第一次读片时仅有横断面图像 ,第二次读片时增加重建图像。结果 :三维重建帮助 4例横断面漏误诊的解剖性异常获得确诊 ,16例炎症性病变进一步详细显示 ,2例气管支气管裂伤明确范围和程度 ;虚拟内窥镜帮助 5例横断面上不能确诊的痰液获得确诊。结论 :CT三维重建可用于解剖性异常和痰液的诊断 ,对其它良性疾病主要是对病变的另一种形式的进一步显示。     

无创面罩通气BiPAP治疗COPD呼吸衰竭32例临床分析

目的 评价双水平气道正压通气（BiPAP）治疗COPD呼吸衰竭患者的疗效，可行性及相关影响因素。方法 回顾性临床分析随机选取32例COPD呼吸衰竭患者给予BiPAP治疗的临床资料，并与84例常规治疗作对照分析。结果 治疗组及对照组均有效，但治疗组住院时间明显缩短p〈0．05；BiPAP治疗后lh有效，一般情况下，3d后各项指标趋于正常。结论 应用BiPAP治疗有显著的临床疗效，可起到事半功倍的效率，减少住院天数。     

Pressure stability of nasal CPAP and bilevel devices

Summary Question of the study   Nasal continuous positive airway pressure (CPAP) prevents collapse of the upper airway during sleep in patients with obstructive sleep apnea provided that a positive transmural pressure can be maintained during inspiration. We examined pressure-flow characteristics in seven CPAP and bilevel devices during spontaneous breathing.
Methods   The CPAP devices were set to a pressure level of 9.8  hPa (10  cm H₂O) and adapted to a pneumotachograph using a standard CPAP hose and an outlet valve. We continuously measured flow, volume and pressure during resting ventilation and increasing voluntary hyperventilation and analysed the dependence of the variables on a breath-to-breath basis.
Results   Mean CPAP pressures differed between the devices (9.9 – 10.6  hPa) despite the same settings. In all machines pressure fell during inspiration to 8.4 – 9.8  hPa and increased during expiration to 11.1 – 11.7  hPa. This effect increased with higher flow rates. Maximum expiratory pressures rose to 12 – 19  hPa at peak flow rates of 2 l/s, mean expiratory pressures to 9.5 – 16  hPa. Inspiratory pressures dropped to 8.5 – 4.5  hPa (minimum) and 10.5 – 6.0 (mean). Bilevel devices showed a higher stability than CPAP devices. Pressure swings during the respiratory cycle increased the additional work of breathing.
Conclusions   Due to differences in mean and effective CPAP levels CPAP devices are not simply exchangeable but should be individually adapted. Patients with higher minute ventilation might benefit from more stable CPAP machines. The impact on patients' compliance remains to be evaluated.     

Topical treatment with aqueous solutions of rofleponide palmitate and budesonide in a pollen-season model of allergic rhinitis

BACKGROUND: Rofleponide palmitate is an esterified glucocorticosteroid pro-drug with a promising pre-clinical profile designed to deliver topical airway treatment for allergic rhinitis and asthma in a novel manner. Thus, the rofleponide palmitate pro-drug is designed to provide topical exposure of the mucosa to the inactive lipophilic drug, which would be locally metabolized to the more hydrophilic and readily cleared drug rofleponide. OBJECTIVE: To examine whether rofleponide palmitate affects nasal symptoms and peak inspiratory flow (PIF) in a pollen-season model of allergic rhinitis and to compare any such effects with those of another glucocorticosteroid (i.e., budesonide). METHODS: During the pollen-free season, 40 patients with strictly seasonal allergic rhinitis received topical nasal spray treatment with an aqueous solution of rofleponide palmitate 400 microg and an aqueous solution of budesonide 128 microg once daily for 10 days in a double-blind, placebo-controlled, and crossover study. After 3 days of drug treatment, individualized allergen challenges were given once daily for 7 days while the treatment continued. The washout periods between each of the challenge series were 2 weeks. Nasal symptoms and PIF were recorded in the morning and evening, as well as 10 and 20 min after each allergen challenge. The mean recordings obtained during the last 3 days of the allergen-challenge series, when symptoms were established and when the treatment had lasted for 8-10 days, were used in the analysis. RESULTS: Both active treatments reduced nasal symptoms and improved nasal PIF compared with placebo (P<0.01-0.001). There was no overall difference in efficacy between rofleponide palmitate 400 microg and budesonide 128 microg. CONCLUSIONS: Topical treatment with aqueous solutions of rofleponide palmitate attenuates nasal symptoms and improves nasal PIF in allergic rhinitis. The overall efficacy of 400 microg of rofleponide palmitate is similar to that of 128 microg of budesonide in the pollen-season model used in this study.     

Removal of laryngeal mask airway: airway complications in children,anaesthetized versus awake*

The laryngeal mask airway (LMA) must be inserted during deep anaesthesia. There are no guidelines concerning the removal of LMA, i.e., in awake or anaesthetized patients. The aim of this randomized prospective study was to compare the incidence of respiratory complications after LMA removal in anaesthetized or awake paediatric patients. Sixty children (ASA PS I or II), ranging from 4 months to 12 years of age, were studied. In patients breathing spontaneously, anaesthesia was induced and maintained with nitrous oxide, oxygen and halothane. Patients were randomly divided into two groups: group 1 removal of LMA in awake patients, or group 2 removal of LMA in anaesthetized patients, i.e., in patients receiving halothane at an alveolar concentration of 2 MAC adjusted for age and oxygen for 5 min. In both groups, patients received 100% oxygen after removal of LMA. After removal the incidence of respiratory complications was highest (P < 0.05) in group 1. Therefore, in healthy children undergoing elective surgery, the authors conclude that it is safer to perform the LMA removal in anaesthetized patients.     

棉尘及吸烟对肺功能影响的观察

对８３名接触棉尘的健康者作肺功能测定，并与３９名不接触棉尘的健康者对照。其中男性均为吸烟者；女性均为不吸烟者。结果表明，ＭＭＥＦ、ＰＥＦＲ、Ｖ２５％～７５％均明显低于对照组（分别为Ｐ＜０．０１和Ｐ＜０．０５）．在男性吸烟组，ＶＣ，ＭＢＣ，ＦＥＶ１％也有明显下降（Ｐ＜０．０１），作者认为棉尘对人体的危害主要部位在小气道，吸烟者因损害严重可累及大气道。以往对棉尘反应的肺功能评估仅以ＦＥＶ１％为指标，不能反映早期的变化，有必要进一步完善。