Combined spinal-propofol anesthesia with noninvasive positive-pressure ventilation

Twenty-three adult patients undergoing repair of inguinal hernia under spinal anesthesia received propofol infusion for sedation with the assist of noninvasive positive-pressure ventilation (NPPV). Circulatory and respiratory parameters, such as percutaneous oxygen saturation, transcutaneous carbon dioxide tension, respiratory rate, tidal volume, blood pressure, and heart rate, were maintained within physiological ranges during the anesthesia. There were no adverse effects. These findings suggest that the application of NPPV in patients receiving propofol infusion for sedation is clinically practicable during anesthesia.     

Full face mask for noninvasive positive-pressure ventilation in patients with acute respiratory failure

BACKGROUND: Noninvasive positive-pressure ventilation (NPPV) is commonly used to improve ventilation and oxygenation in patients with acute respiratory failure (ARF). Mask leak and intolerance due to facial discomfort or claustrophobia often occur with NPPV and are frequently cited reasons for treatment failure. METHODS: Retrospective review of patient records from a tertiary-care referral hospital. Results: We report the effectiveness of a full face mask in the application of NPPV for 10 nonambulatory patients (mean [SD], 61 [9] years) who had a combined total of 13 episodes of ARF. After these patients were unable to receive NPPV therapy via the more commonly available nasal or oronasal masks, care was provided using full face masks. Eight of 10 patients had hypercapnic respiratory failure; 2 patients, hypoxemic respiratory failure. All patients were placed on ventilation initially using a bi-level positive airway pressure device. Subsequently, patient ventilation was achieved using a Puritan Bennett 7200a ventilator for on-line respiratory monitoring. The mean (SD) duration of treatment with NPPV was 9.7 (2.7) hours per day for 3.0 (1.6) days. Following NPPV via full face mask, the patients' Paco(2) decreased (65 [20] vs 82 [27] mm Hg, P=.09) and pH increased significantly (7.36 [0.07] vs 7.26 [0.07], P<.05) in less than 2 hours. Moreover, the patients demonstrated decreased respiratory rate (18 [7] vs 32 [8] breaths/min, P<.01), heart rate (106 [13] vs 124 [16] beats/min, P=.008), and Acute Physiology and Chronic Health Evaluation II scores (12 [3] vs 17 [4], P<.005) after NPPV via full face mask. These cardiorespiratory alterations occurred as early as 1 hour after NPPV initiation and were maintained throughout treatment. Two patients required endotracheal intubation because of copious purulent secretions. CONCLUSION: For individuals with hypercapnic respiratory failure who cannot tolerate NPPV using nasal or oronasal masks, use of full face masks may improve outcomes, allowing physicians to avoid ordering endotracheal intubation and mechanical ventilation.     

Induction of sleep apnoea with negative pressure ventilation in patients with chronic obstructive lung disease.

BACKGROUND: Negative pressure ventilation provides intermittent non-invasive ventilatory assistance for patients with advanced chronic obstructive lung disease. Upper airway obstruction during sleep, a reported complication of the technique, may, however, limit its clinical applicability. METHODS: The effects of nocturnal negative pressure ventilation on ventilation and on indices of sleep quality were investigated in five patients with severe chronic obstructive lung disease (mean (SE) FEV1 31% (3%) predicted) who had completed three months of nightly negative pressure ventilation. Subjects underwent overnight polysomnography on consecutive nights, the first night serving as a control and negative pressure ventilation being provided on the second night. Ventilators were adjusted to result in maximum suppression of the peak phasic electromyogram signal from the diaphragm. RESULTS: Negative pressure ventilation resulted in substantial increases in episodes of obstructive apnoea and hypopnoea (mean (SE)/h 59.3 (19.8) v 3.2 (1.3) on control nights). Most obstructive events, however, were associated with under 3% oxygen desaturation, and the lowest recorded values for overnight oxygen saturation were similar on the two study nights. Negative pressure ventilation was also associated with significant increases in the frequencies of movement arousals and changes in sleep stage. CONCLUSIONS: Negative pressure ventilation applied during sleep to patients with advanced chronic obstructive lung disease may result in the development of recurrent episodes of apnoea and hypopnoea as well as altered sleep quality, which could limit its clinical applicability.     

Alarming hypoxemia during one-lung ventilation in a patient with respiratory bronchiolitis-associated interstitial lung disease

PURPOSE: To report a patient with respiratory bronchiolitis-associated interstitial lung disease (RB-ILD) who developed severe hypoxemia during one-lung ventilation (OLV). CLINICAL FEATURES: A 27-yr-old female, ex-smoker presented with productive cough and dyspnea of 18-month duration. The chest x-ray revealed diffuse abnormalities involving both lungs consisting of interstitial emphysema with irregular shadowing. Preoperative PaO(2) was 88 mmHg and pulmonary function tests showed moderate obstructive disease. The patient underwent right open lung biopsy. After induction of anesthesia, a left double lumen tube was inserted and its position verified with auscultation and fibreoptic bronchoscopy. Upon initiation of OLV, the patient developed severe hypoxemia and the PaO(2) dropped from 500 mmHg during two-lung ventilation (TLV) to 50 mmHg. Hypoxemia was readily corrected by resuming TLV. CONCLUSION: The severe hypoxemia during OLV in this patient with RB-ILD may be attributed to impaired hypoxic pulmonary vasoconstriction. Other causes were not excluded. Caution is warranted when initiating OLV in these patients.     

Prediction of oxygenation during sleep in patients with chronic obstructive lung disease.

The accuracy of a prediction equation for assessing the lowest arterial oxygen saturation (SaO2) during sleep was determined in 24 consecutive patients with chronic obstructive lung disease referred for assessment for home oxygen therapy. Subjects had a mean (SD) FEV1 of 0.81 (0.31) litre and an FEV1/FVC of 37% (12%). There was reasonable agreement between predicted and measured values (mean difference [predicted-measured] = -2.5%) but the prediction was not precise as the 95% confidence interval for the difference was +8% to -13%. The duration of arterial oxygen desaturation, defined as the percentage of total sleep time spent below a given SaO2, was not predicted accurately. It is concluded that nocturnal arterial oxygen desaturation in individual patients with chronic obstructive lung disease cannot be predicted from "awake" measurements with sufficient accuracy to be clinically useful.     

压力调节容积控制通气模式对合并慢性阻塞性肺疾病腹腔镜结直肠手术患者肺保护效应

目的:探讨压力调节容积控制通气（pressure-regulated volume control, PRVC）模式下肺保护性通气（lung-protective ventilation, LPV）对合并慢性阻塞性肺疾病（chronic obstructive pulmonary disease, COPD）腹腔镜结直...     

自我管理教育对无创通气治疗慢性阻塞性肺疾病患者的影响

目的探讨自我管理教育对无创通气治疗慢性阻塞性肺疾病患者的影响。方法成立自我管理教育团队,通过开展多种形式(集体教育活动、小组讨论和个别指导)的自我管理教育活动,对47例实施家庭无创通气治疗超过3个月的COPD患者,进行为期6个月的自我管理教育。结果患者PaCO2、PaO2干预前与干预后3个月、6个月比较,差异有统计学意义(均P<0.01);干预后3个月、6个月患者自我管理能力总分,面罩佩戴、管道消毒、滤纸更换、使用时间、用氧方法及时间、压疮预防、自我效能总分显著提高(均P<0.01);除家庭及朋友支持外,干预后3个月、6个月患者生活质量指数总分,各项目如活动能力、日常生活、健康感受及生活前景得分显著升高(均P<0.01)。结论自我管理教育可以提高COPD的自我管理能力和自我效能,从而减少急性加重的次数,改善患者的整体健康状况。     

比例辅助通气对撤机阶段慢性阻塞性肺疾病合并呼吸衰竭患者通气参数的影响

目的观察比例辅助通气（PAV）与压力支持通气（PSV）对撤机阶段慢性阻塞性肺疾病（COPD）合并呼吸衰竭患者通气参数的影响。方法COPD合并呼吸衰竭患者15例,所有患者均为气管插管并接受机械通气支持1周以上者,在治疗过程中病情稳定准备撤机。随机选用PAV和不同水平的PSV[PSV水平为10cmH2O（PS10）和PSV水平为15cmH2O（PS15）,1cmH20=0．098kPa]辅助通气60min,应用PAV前采用最小平方拟合法（LSF）测定患者的呼吸系统弹性阻力（Ers）和气道阻力（Rrs）,设置容量辅助（VA）和流量辅助（FA）,辅助比例为80％。观察患者在不同通气条件下通气参数及动脉血气分析的变化。结果与低水平PSV（PS10）时相比,高水平PSV（PS15）与PAV时的潮气量显著增加[（443±12）ml与（532±34）ml、（464±23）ml,P〈0．05];PAV时的呼吸频率与气道峰压稍高于PS10时。但差异无统计学意义。PAV支持后,患者的气道闭合压由PS10时的（5．70±0．25）cmH2O降至（4．53±0．25）cmH2O（P〈0．05）,气道压力及吸气触发压力时间乘积也显著降低[由（0．42±0．04）cmH2O降至（0．32±0．03）cmH2O,P〈0．05];而氧合指数与动脉血二氧化碳分压均得到明显改善,与PS15时相近。PAV时的浅快呼吸指数较PS10时无明显改变。结论PAV通过采用正反馈调节机制,成比例地提供同步辅助,显著减少COPD呼吸衰竭患者的自主吸气做功,改善人机同步性。     

Effects of fenoterol on ventilatory response to hypercapnia and hypoxia in patients with chronic obstructive pulmonary disease

BACKGROUND: It has previously been shown that fenoterol, a beta 2 adrenergic agonist, increases the ventilatory response to hypoxia (HVR) and hypercapnia (HCVR) in normal subjects. The effects of beta 2 adrenergic agonists on chemoreceptors in patients with chronic obstructive pulmonary disease (COPD) remain controversial. This study was designed to examine whether fenoterol increases the HVR and HCVR in patients with COPD. METHODS: The HCVR was tested in 20 patients using a rebreathing method and the HVR was examined using a progressive isocapnic hypoxic method. The HCVR and HVR were assessed by calculating the slopes of plots of occlusion pressure (P0.1) and ventilation (VE) against end tidal carbon dioxide pressure (PETCO2) and arterial oxygen saturation (SaO2), respectively. Spirometric values, lung volumes, and respiratory muscle strength were also measured. The HCVR and HVR were examined after the oral administration of fenoterol (15 mg/day) or placebo for seven days. RESULTS: Fenoterol treatment increased the forced expiratory volume in one second (FEV1) and inspiratory muscle strength. In the HCVR the slope of P0.1 versus PETCO2 was increased by fenoterol from 0.35 (0.23) to 0.43 (0.24) (p < 0.01). Moreover, the P0.1 at PETCO2 of 8 kPa was higher on fenoterol than on placebo (p < 0.05) and the VE was also greater (p < 0.01). In the HVR fenoterol treatment increased the P0.1 at 80% SaO2 from 0.90 (0.72) to 0.97 (0.55) kPa (p < 0.05) while the slopes of the response of P0.1 and VE were not changed. CONCLUSIONS: Fenoterol increases the ventilatory response to hypercapnia in patients with COPD, presumably by stimulation of the central chemoreceptor. The hypoxic ventilatory response is only slightly affected by fenoterol.


     

肺保护性通气可减轻轻中度慢性阻塞性肺疾病老年患者围术期肺部感染

目的探讨肺保护性通气对全麻轻中度慢性阻塞性肺疾病(COPD)老年患者围术期肺部感染的影响。方法选择择期行全麻上腹部手术的轻中度COPD老年患者40例,男24例,女16例,年龄65~81岁,ASAⅠ~Ⅲ级,BMI 19~28kg/m~2,采用随机数字表分为肺保护性通气组(PV组)和常规通气组(CV组),每组20例。PV组行肺保护通气:IPPV,V_T 6ml/kg,PEEP 5~10cm H_2O,每隔30分钟进行手法肺复张;CV组行常规通气:IPPV,V_T 10 ml/kg,不使用PEEP及肺复张。于麻醉诱导前(T_1)、机械通气后2h(T_2)、术毕时(T_3)、术后6hT_4)和24h(T_5)采集静脉血检测IL-6和IL-8的浓度;记录麻醉前、术后第1、3、5、7天的临床肺部感染评分(CPIS)和术后肺部炎症发生情况。结果两组患者年龄、BMI、ASA分级、术中输液量、出血量、尿量、机械通气时间、手术方式、T_1~T_5时IL-6和IL-8浓度组间差异均无统计学意义。与T_1时比较,T_2~T_5时两组IL-6和IL-8浓度明显升高(P0.05)。与麻醉前比较,术后第1、3、5天CV组CPIS评分和术后肺部炎症发生率明显升高(P0.05);术后第1、3、5天PV组CPIS评分明显低于CV组(P0.05)。结论肺保护性通气不能降低开腹手术轻中度COPD老年患者围术期IL-6和IL-8浓度,但是可减少术后肺部炎症的发生,减轻术后5d内的肺部感染。     

右美托咪定与吗啡用于慢性阻塞性肺病患者机械通气时对呼吸力学影响的比较

目的研究右美托咪定（dexmedetomidine,DEx）和盐酸吗啡对慢性阻塞性肺病急性发作期（acute exacerbation of chronic obstructive pulmonary disease, AECOPD）行机械通气患者呼吸力学的影响。方法入选AECOPD伴呼吸衰竭行机械通气患者40例;在同样的分钟通气量和呼气末正压的设置下,采用随机对照的方法分为两组（对照组、试验组）,每组20例,对照组使用吗啡进行镇静治疗,实验组使用盐酸DEX。记录两组患者急性生理功能和慢性健康状况评分系统Ⅱ（acute physiology and chronic health evaluation, APACHE Ⅱ）评分、脑电双频指数（bispectral index,BIS）评分、Ramsay镇静评分等指标。比较两组患者镇静前后生命体征、血气的变化和镇静后呼吸力学参数的变化。结果与对照组比较,实验组中平均动脉压（mean arterial pressure,MAP）和脉搏[（80±3）mmHg比（75±4）mmHg（1mmHg=0．133kPa）和（90±3）次/min比（79±3）次/min]降低（P〈0．01）,平均气道压mean airway pressure,Paw）、平台压（plateau pressure,eplat）[（7．5±0．7）cm H2O比（6．2±0．6）cm H2O（1cmH2O=0．098kPa）、（19．8±1．7）cmH20比（18．0±1．1）cmH2O]明显降低（P〈0．01）,峰食道压力（peak esophageal pressure,PPEAKES）、PPEAKEE与基准食道压力差（the peak esophageal manometry reference esophagus pressure difference, dPEs）[（-3．4±0．7）cmH2O比（-5．4±1．0）cmH2O、（-6．9±1．0）cmH2O比（-9．8±1．3）cmH2O]变大（P〈0．01）,吸气末屏气期间的跨肺压（ folding Screen the end of the suction gas during transpulmonary pressure, Ptp Plat）、肺静态顺应性（pulmonary static compliance,cst）[（25．5±2．3）cmH2O比（26．0±2．6）cmH2O、（20．5±1．9）cmH2O比（20．1±1-2）cmH2O]变化无统计学意义（P〉0．05）,气道阻力（airway resistance,Raw）[（20．3±3．9）cmH2O·L-1·s-1比（15．6±1．4）cmH2O·L-1·s-1]变小（P〈0．01）,患者呼吸功（patient work of breathing,WOBp）[（0．11±0．02）j/L比（0．16±0．04）j／L]明显增加[1（P〈0．01）,机械呼吸功（mechanical work of breathing,WOBv）[（0．49±0．10）g/L比（0．43±0．06）j／L]明显降低（P〈0．05）。机械通气时间、重症监护室（ICU）入住时间[（76±5）h比（64±3）h、（6．0±1．5）d比（4．6±0．9）d]减少（P〈0．05）。结论与吗啡比较,DEX能提高机械通气患者的镇静效果、降低Raw、提高肺顺应性,有利于实施保护性通气策略,同时降低呼吸负荷和呼吸做功,因而能降低呼吸氧耗。     

Levalbuterol in the treatment of patients with asthma and chronic obstructive lung disease

Effective asthma control requires long-term (anti-inflammatory) controller medications for patients with mild-persistent to severe-persistent disease, and quick-relief bronchodilator medication for all patients with asthma to control intermittent symptoms of cough, wheeze, and bronchoconstriction, as well as acute exacerbations. For patients with chronic obstructive pulmonary disease, quick-relief and long-acting bronchodilators are primarily used in the maintenance and treatment of associated symptoms, including shortness of breath. For many years, the most widely used bronchodilator has been racemic (R, S)-albuterol, a short-acting beta2-adrenergic agonist, commonly dispensed as an inhaled aerosol or solution. Until the introduction of levalbuterol inhalation solution (Xopenex) in 1999, all marketed forms of albuterol (including Ventolin and Proventil brands) were racemic mixtures composed of a 1:1 ratio of (R)- and (S)-stereoisomers. Administered as a proportionally equivalent nebulized dose, levalbuterol [(R)-albuterol] provides greater bronchodilation than racemic albuterol and, in the appropriate clinical setting, offers the possibility for improving clinical outcomes in patients with asthma and other obstructive airway diseases. Additionally, levalbuterol can be given at lower doses than racemic albuterol to provide comparable bronchodilation, with the potential for reduced beta-mediated adverse effects in adults and children. Only since the past decade has the technology to separate stereoisomers become available, and thus the biologic activities of the albuterol stereoisomers had not been established. Binding studies have demonstrated that (R)-albuterol binds to the beta2-adrenergic receptor with a high affinity, whereas (S)-albuterol binds with 100-fold less affinity than (R)-albuterol. Other evaluations have suggested that (R)-albuterol possesses the bronchodilatory, bronchoprotective, and ciliary-stimulatory properties of racemic albuterol, while (S)-albuterol does not contribute beneficially to the therapeutic effects of the racemate and was originally assumed to be inert. However, preclinical evaluations have shown that (S)-albuterol has effects that work in opposition to (R)-albuterol and may diminish the therapeutic effects of (R)-albuterol.     

Clinical features of polycythaemic patients with chronic obstructive non-specific lung disease

Forty-five patients with chronic hypoxic lung disease were studied to ascertain whether those with polycythaemia had specific distinguishing features. Thirty-three patients had red cell volumes less than 120% of the predicted normal values, and 12 patients had red cell volumes greater than this level and were regarded as polycythaemic. The latter were found to have a higher incidence of the features associated with obstructive bronchitis, whereas the nonpolycythaemic subjects had more emphysematous characteristics. These findings may facilitate the selection of those patients who may benefit from a therapeutic reduction of red cell volume.