高频振荡通气治疗新生儿呼吸衰竭的临床疗效分析

高频振荡通气（HFV）是一种高频通气辅助呼吸方法，具有高频率、小潮气量、低气道压、机械死腔小的通气特点，其通过与常频呼吸机完全不同的作用原理，改善患者的血氧分压和氧合情况，在国外应用于临床已有10余年。我科应用HFV治疗新生儿呼吸窘迫综合征及胎粪吸入综合征、重症肺炎、肺出血、气漏综合征等常频呼吸机械通气疗效差的Ⅱ型呼吸衰竭，     

高频振荡通气治疗新生儿呼吸衰竭的对比性研究

目的探讨高频震荡通气对新生儿重症呼吸衰竭治疗的疗效。方法对比分析36例新生儿重症呼吸衰竭使用传统机械通气失败后改用高频震荡通气治疗前后动脉血氧分压（PaO2）,二氧化碳分压（PCO2）,血氧饱和度（SaO2）,动脉血氧分压与吸入氧浓度之比（PaO2/FiO2）,动脉-肺泡氧张力比值（a/APaO2）,氧合指数（oxygenation index,OI）。结果改高频通气治疗后二氧化碳分压（PaCO2）、氧合指数（OI）下降,（P〈0.01）。动脉血氧分压（PaO2）、动脉血氧分压与吸入氧浓度之比（PaO2/FiO2）、动脉-肺泡氧张力比值（a/APaO2）上升,（P〈0.01）。结论高频震荡通气能更好地改善重症呼吸衰竭新生儿的通气和气体交换,减少气压伤,对治疗新生儿重症呼吸衰竭具有较好的疗效。     

高频振荡呼吸机在新生儿先天性膈疝术后应用的对比性研究

目的探讨高频振荡呼吸机对新生儿先天性膈疝术后治疗的疗效.方法对比分析32例新生儿膈疝术后使用常频和高频呼吸机疗效及其转归.结果高频和常频组治疗后PH 、PaCO2、PO2的变化,p均<0.05,提示两组治疗在改善通气和氧合方面均有效.而高频组上机平均时间较常频组短,且气胸发生率明显降低.结论常频和高频呼吸机均能有效改善通气和氧合,而高频呼吸机在减少气胸发生和缩短上机时间方面更优越.     

高频振荡呼吸机在新生儿先天性膈疝术后应用的对比性研究

目的　探讨高频振荡呼吸机对新生儿先天性膈疝术后治疗的疗效 .方法　对比分析 32例新生儿膈疝术后使用常频和高频呼吸机疗效及其转归 .结果　高频和常频组治疗后PH、PaCO2 、PO2 的变化 ,p均 <0 .0 5 ,提示两组治疗在改善通气和氧合方面均有效 .而高频组上机平均时间较常频组短 ,且气胸发生率明显降低 .结论　常频和高频呼吸机均能有效改善通气和氧合 ,而高频呼吸机在减少气胸发生和缩短上机时间方面更优越     

联合应用PS及机械通气治疗新生儿呼吸窘迫综合征

目的：探讨肺表面活性物质联合机械通气治疗新生儿呼吸窘迫综合征的疗效。方法：联合应用肺表面活性物质和机械通气治疗25例新生儿呼吸窘迫综合征患儿，对治疗前后临床表现、动脉血气、呼吸机参数、胸部X线变化等进行观察。结果：用药后患儿临床症状明显好转，胸部X线透亮度明显改善、颗粒网状阴影消失，血气分析及机械通气参数如FiO2、PIP、PEEP值明显降低（P〈0．01）。结论：肺表面活性物质联合机械通气能迅速有效地治疗新生儿呼吸窘迫综合征。     

部分液体通气对猪急性肺损伤的影响

目的: 在肺灌洗诱导的急性肺损伤(ALI)家猪实施以氟碳(PFC)为媒介的部分液体通气(PLV), 观察其对肺气体交换及血液动力学的影响, 并比较PLV及气体通气两种方式对肺形态学的影响, 以探讨PLV改善肺气体交换的机制。方法: 12头体重为25-30 kg的健康雌猪,麻醉后经肺灌洗建立ALI模型。随机分为PLV组及CV(气体通气组)。对照组以呼吸机行常规机械通气, PLV组动物经气管导管肺内灌以15 mL/kg的PFC,然后以与对照组同样的呼吸参数行机械通气。每小时记录肺气体交换及血液动力学参数的变化。于实验结束后处死动物, 取肺标本送病理分析。 结果: PLV组肺气体交换明显改善,而血液动力学在整个实验过程中基本维持稳定。组织学检查: 光学显微镜下可见两组均为肺不张、肺气肿及肺过度膨胀交替出现,肺泡间质因水肿及细胞渗出而扩展。PLV组与CV组比较显示较轻微的肺不张、肺内炎性细胞渗出、肺出血及肺间质扩张。PLV组动物腹侧肺组织学损伤改变明显较背侧轻微。 结论: 在肺灌洗诱导的急性肺损伤幼猪, 以氟碳为媒介的部分液体通气可明显地改善肺气体交换,并无明显的血液动力学损伤。同时可见PLV相对于对照组明显减轻的肺组织学损伤及肺泡扩张, 证实PLV具一定的肺保护作用。     

高频振荡通气与同步间歇指令通气在新生儿肺炎合并气胸患儿中的应用效果比较

目的:比较高频振荡通气(High-frequency oscillatory ventilation,HFOV)、同步间歇指令通气(Synchronized intermittent mandatory ventilation,SIMV)两种模式在新生儿肺炎合并气胸患儿中的应用效果.方法:回顾性分析我院2017年10月至2020年9月89例新生儿肺炎合并气胸患儿的临床资料,按所用通气模式不同分为HFOV组(n=47)和SIMV组(n=42).比较两组肺泡复张时间、通气治疗时间、住院时间、治疗前、治疗1 d后、治疗3 d后血气指标、血清炎性因子和心肌酶谱水平及并发症发生率.结果:两组肺泡复张时间比较差异无统计学意义(P>0.05),HFOV组通气治疗时间、住院时间均短于SIMV组(P<0.05);治疗1d后、3d后两组动脉血氧分压、血氧饱和度水平升高,HFOV组高于SIMV组,动脉血二氧化碳分压水平降低,HFOV组低于SIMV组(P<0.05);治疗1 d后、3 d后两组血清肿瘤坏死因子-α、白细胞介素-6水平及乳酸脱氢酶、肌酸激酶、肌酸激酶同工酶水平均降低,HFOV组低于SIMV组(P<0.05);两组并发症发生率无明显差异(P>0.05).结论:与SIMV比较,HFOV治疗模式在改善动脉血气状态、缓解机体炎症、减轻心肌损伤方面更具优势,可有效促进新生儿肺炎合并气胸患儿病情康复,临床应用价值较高.     

与高频震荡通气有关的潜在性危害及其防治

１概述［１］ 自从１９７２年ｌｕｎｋｅｎｈｅｉｍｅｒ等在用高频震荡器研究心肌阻抗的实验时发现高频震荡通气（ ｈｉｇｈ ｆｒｅ－ｑｕｅｎｃｅ　 ｏｓｃｉｌｌａｔｏｒｙ ｖｅｎｔｉｌａｔｉｏｎ， ＨＦＯＶ） 可以保持有效气体交换后，近十余年来人们不断通过对其作用机理、临床参数调节及肺力学参数监测等方面进行广泛研究，体会到ＨＦＯＶ在机械通气治疗方面确实起到一些独特的作用．如在呼吸窘迫综合征（ＲＤＳ）动物实验中，ＨＦＯＶ和常频机械通气（ＣＶ）两种方法相比，表明ＨＦＯＶ可以减少气漏发生，使肺均匀膨胀，改善气体交…     

有创与无创正压机械通气对重度型呼吸衰竭的随机对照研究

目的:评价无创正压通气与有创通气对重度Ⅱ型呼吸衰竭患者的效果。方法:31例重度呼吸衰竭患者随机分为无创正压组及有创组。无创正压组15例经鼻面罩接呼吸机,有创组16例气管插管。结果:有创组通气2h后,PaO2明显上升(P<0.05),PaO2明显下降(P<0.05),神志开始清醒,平均通气时间6±3d,成功拔管13例,有效率81.2%;无创正压组治疗2h后,动脉血气PaO2明显上升(P<0.05),PaO2下降不明显(P>0.05),6例(40.0%)最后改为有创通气,有9例避免了插管,降低插管率为60.0%,无创正压组死亡率为36.6%,高于有创组(P<0.05)。结论:有创通气短期改善重度呼吸衰竭患者动脉血气的效果优于无创正压,无创正压组有60.0%避免了插管,但死亡率高于有创组。危重的Ⅱ型呼吸衰竭有创通气疗效优于无创正压通气。     

有创-无创序贯通气疗法治疗慢性阻塞性肺疾病 引发的严重呼吸衰竭的临床研究

目的 对照研究以肺部感染控制窗为切换点行有创与无创序贯机械通气治疗慢性阻塞性肺疾病所致严重呼吸衰竭的临床疗效。方法 选取2017年2月~2018年2月在我院诊治的130例慢性阻塞性肺疾病所致严重呼吸衰竭患者为研究对象,依据随机数字表法分为对照组和观察组,各65例,对照组采用常规有创通气治疗,观察组采用有创-无创序贯通气治疗,观察对比两组并发症发生率、通气时间等指标。结果 观察组动脉血氧饱和度、二氧化碳分压、动脉血氧分压、动脉血气指标与对照组对比,差异无统计学意义（P＞0.05）;观察组有创通气时间短于对照组,呼吸机相关肺炎发生率低于对照组,ICU入住时间短于对照组,病死率低于对照组,差异有统计学意义（P＜0.05）。结论 以PIC窗为切换点采用有创与无创序贯机械通气治疗慢性阻塞性肺疾病急性加重合并呼吸衰竭,可缩短有创通气时间,显著改善动脉血气指标,降低病死率。     

高频震荡通气技术研究现状分析与展望

以低平均气道压和小潮气量为主要特征的高频震荡通气(HFOV),自出现以来备受医务、科研人员的关注。本文就HFOV通气技术方面的研究现状与发展趋势进行了分析和展望,重点介绍与分析了有关HFOV的通气模型、通气机制和通气模式方面的研究现状。并藉此提出,在未来一段时期内,对HFOV通气技术的研究将主要集中在三个方面:建立多级、高阶、非线性的黏性阻力、惯性阻力和顺应性(RIC)通气模型;更为充分地揭示HFOV之所以能够有效通气的机制;研究实现低风险的无创HFOV。对HFOV通气技术的研究与发展,将为呼吸系统疾病患者提供一种不同于常频通气的通气方式。     

Utilization of the lower inflection point of the pressure-volume curve results in protective conventional ventilation comparable to high frequency oscillatory ventilation in an animal model of acute respiratory distress syndrome

INTRODUCTION: Studies comparing high frequency oscillatory and conventional ventilation in acute respiratory distress syndrome have used low values of positive end-expiratory pressure and identified a need for better recruitment and pulmonary stability with high frequency. OBJECTIVE: To compare conventional and high frequency ventilation using the lower inflection point of the pressure-volume curve as the determinant of positive end-expiratory pressure to obtain similar levels of recruitment and alveolar stability. METHODS: After lung lavage of adult rabbits and lower inflection point determination, two groups were randomized: conventional (positive end-expiratory pressure = lower inflection point; tidal volume=6 ml/kg) and high frequency ventilation (mean airway pressures= lower inflection point +4 cmH2O). Blood gas and hemodynamic data were recorded over 4 h. After sacrifice, protein analysis from lung lavage and histologic evaluation were performed. RESULTS: The oxygenation parameters, protein and histological data were similar, except for the fact that significantly more normal alveoli were observed upon protective ventilation. High frequency ventilation led to lower PaCO2 levels. DISCUSSION: Determination of the lower inflection point of the pressure-volume curve is important for setting the minimum end expiratory pressure needed to keep the airways opened. This is useful when comparing different strategies to treat severe respiratory insufficiency, optimizing conventional ventilation, improving oxygenation and reducing lung injury. CONCLUSIONS: Utilization of the lower inflection point of the pressure-volume curve in the ventilation strategies considered in this study resulted in comparable efficacy with regards to oxygenation and hemodynamics, a high PaCO2 level and a lower pH. In addition, a greater number of normal alveoli were found after protective conventional ventilation in an animal model of acute respiratory distress syndrome.     

外柱细胞软化对Corti器感音影响的生物力学研究

Corti器的感音过程容易受到内部结构属性变化的影响。外柱细胞血管舒张刺激磷蛋白缺失会减缓肌动蛋白丝的形成,从而产生听力延迟。本研究运用COMSOL建立三维有限元模型研究肌动蛋白缺失导致外柱细胞软化时,Corti器感音过程中基底膜和外毛细胞与Deiters细胞结合点的力学行为变化。结果表明,外柱细胞软化会削弱外毛细胞主动力对基底膜位移增益的放大作用,但削弱作用并不会立即产生,Corti器存在维持正常功能的“缓冲”阶段。在100 dB和120 dB之间可能存在一个声压级临界值,在该临界值两侧外柱细胞软化对基底膜应力变化的影响是截然相反的。另外外柱细胞软化对不同外毛细胞与Deiters细胞结合点力学行为的影响也不同,位移增益优先级会因此产生改变。     

Necrotizing Tracheobronchitis: A complication of high frequency jet ventilation

Summary The tracheal and bronchial lesions observed are described in seven patients, presenting with respiratory distress syndrome and receiving both conventional and high frequency jet ventilation for various periods. The histological findings are related to the duration of the exposure as well as the number of pulsations administered to the tracheobronchial tree. Severe damage to the mucosa leading to acute tracheobronchitis, hyperplasia and hypersecretion of the mucosal glands may explain some of the clinical symptoms observed, especially the upper respiratory obstruction. Care should be taken to limit these changes which may lead to various degrees of stenosis in survivors receiving this mode of therapy.     

术侧不同通气方式对单肺通气期间肺保护作用的研究进展

良好的肺隔离技术是胸科手术顺利进行的保障,单肺通气可导致低氧血症和肺内分流及急性肺损伤。目前,改善低氧血症和肺内分流及急性肺损伤的方法主要有药物应用、麻醉方式、容量治疗和通气模式等方面。对非通气侧肺的研究较少,非通气侧实施持续正压通气或高频喷射通气是胸部手术的一种气道管理策略。该文将对非通气侧行持续正压通气和高频喷射通气两种不同的辅助通气方式对改善肺部并发症的最新研究进展做一综述。     

Flow transport and gas mixing during invasive high frequency oscillatory ventilation

A large Eddy simulation (LES) based computational fluid dynamics study was performed to investigate gas transport and mixing in patient specific human lung models during high frequency oscillatory ventilation. Different pressure-controlled waveforms (sinusoidal, exponential and square) and ventilator frequencies (15, 10 and 6 Hz) were used (tidal volume = 50 mL). The waveforms were created by solving the equation of motion subjected to constant lung wall compliance and flow resistance. Simulations were conducted with and without endotracheal tube to understand the effect of invasive management device. Variation of pressure-controlled waveform and frequency exhibits significant differences on counter flow pattern, which could lead to a significant impact on the gas mixing efficiency. Pendelluft-like flow was present for the sinusoidal waveform at all frequencies but occurred only at early inspiration for the square waveform at highest frequency. The square waveform was most efficient for gas mixing, resulting in the least wall shear stress on the lung epithelium layer thereby reducing the risk of barotrauma to both airways and the alveoli for patients undergoing therapy.     

Interaction between high frequency jet ventilation and cardiovascular function

We have studied the interaction of high frequency jet ventilation with cardiovascular pressures and flows. Results in dogs show that the amplitude of all intrathoracic pressures and flows fluctuate with a frequency equal to the difference between the heart rate and ventilator rate. The magnitude of this amplitude variation may be sufficient to obliterate periodically the pulsations in pulmonary artery and right atrial pressures. It is also shown that these cardiovascular beats can occur when the ventilator rate is close to integral multiples of the heart rate. Direct measurement of pleural pressure and the observation that the beats are markedly reduced when the chest is open support the hypothesis that the primary mechanism responsible for these beats is the interaction of the respiratory fluctuations in pleural pressure with the cardiacgenerated pressure pulsations.     

Linear servo-controlled pressure generator for forced oscillation measurements

In respiratory input impedance measurements, the low-frequency range contains important clinical and physiological information. However, the patient's spontaneous ventilation can contaminate the data in this range, leading to unreliable results. Unbiased estimators are a good alternative to overcome this problem, provided that the generator is considered linear. This condition is not fulfilled by most existing generators as they are based on loudspeakers, which have strong nonlinearities. The present work aims to contribute to the solution of this problem, and describes a pressure generator that minimises the nonlinearities by an optical sensor placed in a position feedback loop. The static evaluation shows a high linearity for the optical system. The well known frequency response of pressure transducers is used in the dynamic evaluation of the instrument. The analysis of the generator shows that the use of position feedback improved the frequency response. The total harmonic distortion (THD) measurement shows that closed loop resulted in an effective decrease in the nonlinearities. The reduction of THD achieved by the servo-controlled generator can contribute to the practical implementation of the unbiased estimators, increasing the reliability of the impedance data, especially in the low-frequency range. This system is compared with conventional generators and with another servo-controlled system.     

Numerical simulation of aerosol particle transport by oscillating flow in respiratory airways

Particle transport by oscillating flow in a tapered channel or in a tapered tube was computed from the complete equations of motion. These geometries represent a simplified model of the divergent flow field of the mammalian bronchial tree. The computed deformation profile of a line of particles, transported by the oscillatory motion, was compared with prior experimental results and analytical calculations. All three methods agree that there is transport in the divergent direction of the tube by an axial stream of steady drift in the core for moderately high frequency of oscillation (Womersley parameter in the range of 1 to 10). Bidirectional flow is established by an annular stream in the convergent direction, with no net flow on integral cycles of the oscillating fluid. At higher frequency, however, the steady stream transforms to a different shape in the tapered tube, with transport in the divergent direction nearer the walls of the tube, rather than in the core. Transport by the continuing streams with oscillatory ventilation of the respiratory tract should deliver medicinal aerosols of low intrinsic particle mobility to the peripheral regions of the lungs.