呼吸道合胞病毒毛细支气管炎婴幼儿肺功能变化及其在临床诊断和治疗评估中的价值

目的探讨呼吸道合胞病毒毛细支气管炎肺功能的变化及其在临床诊断和治疗评估中的作用。方法对110例呼吸道合胞病毒毛细支气管炎患儿进行肺功能测定,并与49例正常健康儿童进行对照,观察患儿潮气流速-容量环的形态及各项指标的变化。回顾性调查患儿临床病情评分、住院天数,与肺功能主要参数进行相关性分析。结果呼吸道合胞病毒毛细支气管炎患儿潮气流速-容量环变窄,呼气曲线升枝陡峭,高峰提前,降枝呈波谷样凹陷。呼吸道合胞病毒毛细支气管炎患儿呼吸频率(RR)、呼气峰流速/潮气量(PF/VE)、呼气峰流速/呼气达峰时间(PTEF/TPTEF)增加,每千克体重潮气量(VT/kg)、吸呼比(TI/TE)、呼气达峰时间(TPTEF)、达峰时间比(TPTEF/TE)、呼气达峰容积(VPTEF)、达峰容积比(%V-PF)、呼出75%潮气量时的呼气流速(TEF25%)、呼出75%潮气量时的呼气流速/呼气峰流速(25/PF)降低,与同年龄正常组比较差异均有显著性意义;呼气峰流速(PTEF)、呼气中期流速(ME)、吸气中期流速(MI)、呼气中期流速/吸气中期流速(ME/MI)无显著性差异。代表小气道功能的主要参数指标%V-PF、25/PF与患儿临床病情评分中度相关,与住院天数低度相关。结论呼吸道合胞病毒毛细支气管炎急性期肺功能主要表现为小气道阻塞性通气障碍;潮气呼吸肺功能测定可作为该病临床诊断、病情预后评估的客观依据。     

呼吸道合胞病毒毛细支气管炎婴幼儿肺功能变化及其在临诊断和治疗评估中的价值

目的探讨呼吸道合胞病毒毛细支气管炎肺功能的变化及其在临床诊断和治疗评估中的作用。方法对110例呼吸道合胞病毒毛细支气管炎患儿进行肺功能测定，并与49例正常健康儿童进行对照，观察患儿潮气流速-容量环的形态及各项指标的变化。回顾性渊查患儿临床病情评分、住院天数，与肺功能主要参数进行相关陛分析。结果呼吸道合胞病毒毛细支气管炎患儿潮气流速-容量环变窄，呼气曲线升枝陡峭，高峰提前，降枝呈波谷样凹陷。呼吸道合胞病毒毛细支气管炎患儿呼吸频率（RR）、呼气峰流速／潮气量（PF／VE）、呼气峰流速／呼气达峰时间（PTEF／TPTEF）增加，每千克体重潮气量（VT／kg）、吸呼比（TI/TE）、呼气达峰时间（TPTEF）、达峰时间比（TPTEF/TE）、呼气达峰容积（VPTEF）、达峰容积比（％V-PF）、呼出75％潮气量时的呼气流速（TEF25％）、呼出75％潮气量时的呼气流速／呼气峰流速（25／PF）降低，与同年龄正常组比较差异均有显著性意义；呼气峰流速（PTEF）、呼气中期流速（ME）、吸气中期流速（MI）、呼气中期流速／吸气中期流速（ME／MI）无显著性差异。代表小气道功能的主要参数指标％V—PF、25／PF与患儿临床病情评分中度相关，与住院天数低度相关。结论呼吸道合胞病毒毛细支气管炎急性期肺功能主要表现为小气道阻塞性通气障碍；潮气呼吸肺功能测定可作为该病临床诊断、病情预后评估的客观依据。     

毛细支气管炎患儿的肺功能检测及其临床意义

目的 观察毛细支气管炎患儿的肺功能动态变化情况并探讨其临床意义.方法 采用比利时麦迪HYPAIR M型肺功能仪,运用潮气呼吸流速容量环对100例毛细支气管炎患儿急性期、恢复期进行肺功能检查.结果 在毛细支气管炎急性期,肺功能大多呈中度以上阻塞性通气功能障碍,呼吸频率(R)增高,每千克体重潮气量(VT/kg)、达峰时间比(TPTEF/TE)及达峰容积时间比(VPTEF/VE)均下降,与临床恢复期比较差异有统计学意义.结论 毛细支气管炎急性期,肺功能呈现小气道阻力增高、阻塞性通气功能障碍改变,恢复期小气道功能好转,说明小气道功能异常能在较短时间内恢复.肺功能检查是判断病情、评估疗效、推断预后的实用和可靠的方法.     

潮气呼吸流速容量环对毛细支气管炎患儿肺功能的评价

目的:研究毛细支气管炎时小气道阻塞的程度及动态变化的情况,并探讨其临床意义。方法:采用德国耶格公司MasterScreen小儿肺功能仪,运用潮气呼吸流速容量环评价115例毛细支气管炎急性期婴儿(按月龄分为3组)肺功能。并对其中30例患儿进行临床恢复期肺功能复查。结果:115例患儿中肺功能正常5例,单纯限制性改变3例,余107例患儿均有不同程度的气道阻塞性改变,其中轻度阻塞(达峰时间比为28%-22%)25例,占23.3%,中度阻塞(达峰时间比为22%-16%)34例,占31.7%,重度阻塞(达峰时间比为<16%)48例,占44.8%。中度以上阻塞的患儿约达76%。107例患儿中有38例同时伴有限制性改变。临床恢复期上述异常指标明显好转。结论:毛细支气管炎急性期,肺功能大多呈中度以上阻塞性通气功能障碍,主要为小气道阻塞,恢复期有显著好转。潮气呼吸流速容量环检测能较好地反映小婴儿的肺功能。     

毛细支气管炎患儿治疗中测定潮气流速容量曲线的意义

潮气流速容量曲线测定是近年来国内开展的检测气道阻塞性疾病最好的方法之一,它能对气道阻塞的程度进行定性和定位诊断[1]。毛细支气管炎俗称喘憋性肺炎,主要由呼吸道合胞病毒、流感病毒、副流感病毒、腺病毒引起的毛细支气管的炎症,多发生于2岁以内的婴幼儿。2000年3月-2003年     

婴幼儿肺功能检测在呼吸系统疾病的作用和意义

目的:了解婴幼儿肺功能检测在临床应用的意义.方法:用美国森迪氏公司2 600婴幼儿肺功能仪做4 228例婴幼儿肺功能检测.包括用潮气流速环了解大、小气道功能、用开放性氮冲洗法检测功能残气量、呼吸系统顺应性和总气道阻力是用被动流速容量技术测出的.结果:婴幼儿肺功能检测总阳性率为88%,各种呼吸道疾病有不同的肺功能特点,各种指标的阳性率也有不同.毛细支气管炎、喘息性支气管肺炎和婴幼儿哮喘的惠儿大部分都有小气道阻力增高,其阳性率分别为58.3%,60%,64%.功能残气量异常为主.而先天性喉喘鸣的喉炎的肺功能检查以大气道功能异常的阳性率是30%左右,远比其他的呼吸道疾病要高:肺不张的患者以小气道功能异常、总气道阻力增高为主和功能残气量下降为主要改变,这与肺不张的病理生理改变十分吻合:此组患者的最大人群为支气管肺炎,则是既有小气道阻力增高改变,又有总气道阻力增高和功能残气量改变,但功能残气量升高、降低的比例相差不大,这和支气管肺炎是以阻塞为主,还是实变为主有相当大的关系.咳嗽变异性哮喘的患儿有25.4%有小气道阻力增高,而功能残气量也有一定的变化.结论:婴幼儿肺功能检测对婴幼儿肺生长发育监测,各种疾病转归、诊断、药物疗效评定等均具有很重要的临床意义.     

婴幼儿肺功能的检测与护理

目的检测婴幼儿患呼吸系统疾患时肺功能状况,研究探讨2600型小儿肺功能仪操作方法,以协助临床诊断并指导治疗.方法采用SensorMedics2600型小儿肺功能仪,对611例呼吸系统疾患婴幼儿进行睡眠时潮气呼吸流速容量(TBFV)环、被动呼气流速容量(PFV)曲线检查,部分患儿进行功能残气量(FRC)测定.结果611例患儿中检出肺功能异常者558例(91.32%).其中表现小气道阻力升高505例(82.65%),大气道阻力升高401例(65.63%);同时有大、小气道阻力升高348例(56.96%);呼吸系统静态顺应性降低149例(24.39%),增高6例(0.98%).279例功能残气量测试,增高46例(16.49%),减少104例(37.28%).162例支气管舒张试验阳性68例(41.98%);阴性94例(58.02%).各项指标均正常53例(9.33%).结论本检测方法客观地反映了患儿潮气通气量指标、气道阻力、颇应性、功能残气量情况及气道可逆性,对指导临床诊断治疗及疗效判断有重要的应用意义,正确的操作方法保证了测试结果的准确性和可靠性.     

体描箱评价脊柱侧弯幼儿的肺功能变化

背景:肺功能检查是脊柱侧弯矫正前评价手术风险的重要手段,寻找一种简便、有效的检测肺功能评估方法是低龄儿童脊柱侧弯手术时机选择及治疗效果评价的迫切要求。目的:应用体描箱评价脊柱侧弯幼儿的肺功能变化。方法:纳入脊柱侧弯患儿31例,健康对照幼儿50例。采用德国耶格公司生产的婴儿体描箱进行肺功能指标检测,包括潮气量、分钟通气量、达峰容积比、达峰时间比、潮气呼气峰流速、25%,50%,75%潮气量时的潮气呼气流速、呼吸频率、功能残气量及有效气道阻力。结果与结论:脊柱侧弯组患儿功能残气量明显低于健康组(P<0.01),有效气道阻力明显高于健康组(P<0.01),分钟通气量、潮气呼气峰流速及75%潮气量时的潮气呼气流速均明显低于健康组(P<0.05)。提示功能残气量、有效气道阻力是体描箱测定的经典指标,脊柱侧弯患儿功能残气量明显减低,气道阻力明显增高。体描箱可作为检测低龄脊柱侧弯患儿肺功能的重要手段。     

体描箱评价脊柱侧弯幼儿的肺功能变化

背景：肺功能检查是脊柱侧弯矫正前评价手术风险的重要手段,寻找一种简便、有效的检测肺功能评估方法是低龄儿童脊柱侧弯手术时机选择及治疗效果评价的迫切要求.目的：应用体描箱评价脊柱侧弯幼儿的肺功能变化.方法：纳入脊柱侧弯患儿31例,健康对照幼儿50例.采用德国耶格公司生产的婴儿体描箱进行肺功能指标检测,包括潮气量、分钟通气量、达峰容积比、达峰时间比、潮气呼气峰流速、25%,50%,75%潮气量时的潮气呼气流速、呼吸频率、功能残气量及有效气道阻力.结果与结论：脊柱侧弯组患儿功能残气量明显低于健康组（P 〈 0.01）,有效气道阻力明显高于健康组（P 〈 0.01）,分钟通气量、潮气呼气峰流速及75%潮气量时的潮气呼气流速均明显低于健康组（P 〈 0.05）.提示功能残气量、有效气道阻力是体描箱测定的经典指标,脊柱侧弯患儿功能残气量明显减低,气道阻力明显增高.体描箱可作为检测低龄脊柱侧弯患儿肺功能的重要手段.     

婴幼儿肺功能的检测与护理

目的 检测婴幼儿患呼吸系统疾患时肺功能状况，研究探讨2600型小儿肺功能仪操作方法，以协助临床诊断并指导治疗。方法 采用SensorMedics2600型小儿肺功能仪，对611例呼吸系统疾患婴幼儿进行睡眠时潮气呼吸流速容量（TBFV）环、被动呼气流速容量（PFV）曲线检查，部分患儿进行功能残气量（FRC）测定。结果 611例患儿中检出肺功能异常者558例（91．32％）。其中表现小气道阻力升高505例（82．65％），大气道阻力升高401例（65．63％）；同时有大、小气道阻力升高348例（56．96％）；呼吸系统静态顺应性降低149例（24．39％），增高6例（0．98％）。279例功能残气量测试，增高46例（16．49％），减少104例（37．28％）。162例支气管舒张试验阳性68例（41．98％）；阴性94例（58．02％）。各项指标均正常53例（9．33％）。结论 本检测方法客观地反映了患儿潮气通气量指标、气道阻力、顺应性、功能残气量情况及气道可逆性，对指导临床诊断治疗及疗效判断有重要的应用意义，正确的操作方法保证了测试结果的准确性和可靠性。     

Tidal pressure/volume and flow/volume respiratory loop patterns in human neonates

1. Tidal pressure/volume and flow/volume respiratory loops were constructed from records obtained during 98 studies on 48 neonates of various ages and gestations. Records were obtained with a total body plethysmograph and an oesophageal balloon. Total pulmonary resistance was computed at five separate levels in the breathing cycle and results were expressed graphically as tidal resistance profiles by plotting total pulmonary resistance against percentage tidal volume above functional residual capacity. 2. Values obtained for standard pulmonary mechanical measurements and thoracic gas volume were similar to those of other workers. In addition six distinctive resistance profile patterns were found and related to different breathing patterns. 3. The technique appeared to be particularly useful in identifying air trapping and also demonstrated that total pulmonary resistance is open to misinterpretation when measured only at the mid-tidal-volume level, as is the present convention.     

肺炎患儿潮气呼吸肺功能检测及其临床意义

目的观察婴儿肺炎的潮气呼吸肺功能动态变化并探讨其临床意义。方法采用德国耶格公司婴幼儿肺功能仪,对23例肺炎婴儿急性期、恢复期及15例正常婴儿进行肺功能检查,统计方法采用单因素方差分析,两两比较采用q检验。结果肺炎急性期组与恢复期组及正常组比较,呼吸频率（RR）、潮气峰值流速与潮气量的比率（PTEF/Vt）明显增高,每千克体重潮气量（Vt/kg）明显下降,差异有显著性;潮气峰值流速（PTEF）、达峰时间比（tPTEF/tE）及达峰容积比（vPTEF/vE）等指标差异均无显著性（P〉0.05）。结论肺炎婴儿急性期肺功能并不等同于毛细支气管炎肺功能表现,它主要表现为Vt/kg、RR、PEF/VT的改变,而非tPTEF/tE、vPTEF/vE的改变,Vt/kg、RR、PEF/VT可作为观察本病病情变化的敏感指标。     

Measurement of air trapping, intrinsic positive end-expiratory pressure, and dynamic hyperinflation in mechanically ventilated patients

Severe airflow obstruction is a common cause of acute respiratory failure. Dynamic hyperinflation affects tidal ventilation, increases airways resistance, and causes intrinsic positive end-expiratory pressure (auto-PEEP). Most patients with asthma and chronic obstructive pulmonary disease have dynamic hyperinflation and auto-PEEP during mechanical ventilation, which can cause hemodynamic compromise and barotrauma. Auto-PEEP can be identified in passively breathing patients by observation of real-time ventilator flow and pressure graphics. In spontaneously breathing patients, auto-PEEP is measured by simultaneous recordings of esophageal and flow waveforms. The ventilatory pattern should be directed toward minimizing dynamic hyperinflation and auto-PEEP by using small tidal volume and preserving expiratory time. With a spontaneously breathing patient, to reduce the work of breathing and improve patient-ventilator interaction, it is crucial to set an adequate inspiratory flow, inspiratory time, trigger sensitivity, and ventilator-applied PEEP. Ventilator graphics are invaluable for monitoring and treatment decisions at the bedside.     

Comparison of two different CPAP systems by tidal breathing parameters

OBJECTIVE: Comparison of tidal breathing and pressure fluctuation of the continuous positive airway pressure (CPAP) associated with the use of the valveless Infant Flow System versus the conventional constant-flow CPAP (Babylog 8000) in preterm infants. DESIGN: Randomized cross-over trial. SETTING: Neonatal intensive care unit level III. PATIENTS: Twenty infants; median (range): birth weight 1,035 g (640-4,110 g), actual weight 1,165 g (820-4,250 g), gestational age at birth 27 (26-40) weeks. INTERVENTIONS: After extubation two CPAP devices (Infant Flow System vs Babylog 8000) were applied in a random order to the same infant. Fluctuations of the applied pressure during the breathing cycle and tidal breathing parameters were measured by the flow-through technique. MAIN RESULTS: Using the Infant Flow System the mean (standard deviation) inspiratory flow [1.5 (0.1) vs 1.3 (0.1) l.min(-1).kg(-1), P<0.05] and tidal volume were significantly increased [5.3 (1.3) vs 4.7 (1.3) ml/kg(-1), P<0.05] compared to Babylog 8000. The fluctuations of the applied pressure of the Infant Flow System during the breathing cycle were significantly lower [0.1 (0.03) kPa vs 0.15 (0.08) kPa, P<0.05] compared to Babylog 8000. No differences were seen in the duration of inspiration and expiration and the time to peak tidal flow. In the Infant Flow System pressures during expiration remained stable whereas they increased during the use of Babylog 8000. CONCLUSIONS: Within-subject comparisons of tidal breathing parameters of the two CPAP devices Infant Flow System and Babylog 8000 show: (1) a significant influence of the system used; and (2) that the valveless Infant Flow System increases air flow and tidal volume with less fluctuations in CPAP pressures during the breathing cycle.     

Effects of tidal volume on work of breathing during lung-protective ventilation in patients with acute lung injury and acute respiratory distress syndrome

OBJECTIVE: To assess the effects of step-changes in tidal volume on work of breathing during lung-protective ventilation in patients with acute lung injury (ALI) or the acute respiratory distress syndrome (ARDS). DESIGN: Prospective, nonconsecutive patients with ALI/ARDS. SETTING: Adult surgical, trauma, and medical intensive care units at a major inner-city, university-affiliated hospital. PATIENTS: Ten patients with ALI/ARDS managed clinically with lung-protective ventilation. INTERVENTIONS: Five patients were ventilated at a progressively smaller tidal volume in 1 mL/kg steps between 8 and 5 mL/kg; five other patients were ventilated at a progressively larger tidal volume from 5 to 8 mL/kg. The volume mode was used with a flow rate of 75 L/min. Minute ventilation was maintained constant at each tidal volume setting. Afterward, patients were placed on continuous positive airway pressure for 1-2 mins to measure their spontaneous tidal volume. MEASUREMENTS AND MAIN RESULTS: Work of breathing and other variables were measured with a pulmonary mechanics monitor (Bicore CP-100). Work of breathing progressively increased (0.86 +/- 0.32, 1.05 +/- 0.40, 1.22 +/- 0.36, and 1.57 +/- 0.43 J/L) at a tidal volume of 8, 7, 6, and 5 mL/kg, respectively. In nine of ten patients there was a strong negative correlation between work of breathing and the ventilator-to-patient tidal volume difference (R = -.75 to -.998). CONCLUSIONS:: The ventilator-delivered tidal volume exerts an independent influence on work of breathing during lung-protective ventilation in patients with ALI/ARDS. Patient work of breathing is inversely related to the difference between the ventilator-delivered tidal volume and patient-generated tidal volume during a brief trial of unassisted breathing.     

Tidal breathing flow-volume loops in bronchiolitis in infancy: the effect of albuterol [ISRCTN47364493]

Objectives  

To evaluate the effect of nebulized albuterol on tidal breathing flow-volume loops in infants with bronchiolitis due to respiratory syncytial virus.     

Regional distribution of pulmonary ventilation and perfusion in elderly subjects

Using radioactive xenon, we measured the regional distribution of pulmonary ventilation and blood flow in six normal men, whose ages ranged between 65 and 75 yr. The measurements were made in the standing position. The static volume-pressure relation of the lungs was also measured in five of the subjects. The results indicate that by comparison with normal young men: (a) Blood flow to the upper lung zones was increased, although it still remained predominant in the lower zones. (b) Ventilation distribution during a vital capacity inspiration was similar to that seen in young subjects. (c) In five of the six elderly subjects, however, the distribution of ventilation in the resting tidal volume range was not preferential to the lower zones as it was in young men. This was probably caused by airway closure in the lower lung zones. The elderly subjects thus exhibit during normal tidal volume breathing a ventilation distribution pattern similar to that observed in young subjects when breathing at low lung volumes, i.e., near residual volume. This difference is probably due to the combined effect of the loss in elastic recoil of the lungs observed in the elderly subjects and of a decreased resistance to collapse of the aged airways. These findings suggest that in the elderly subjects there is a significant regional ventilation-perfusion impairment during quiet breathing, which may explain in part the reported increase in alveolar-arterial oxygen difference with advancing age.     

Static and dynamic pressure-volume curves reflect different aspects of respiratory system mechanics in experimental acute respiratory distress syndrome.

INTRODUCTION: A lower inflection point, an upper inflection (or deflection) point, and respiratory system compliance can be estimated from an inspiratory static pressure-volume (SPV) curve of the respiratory system. Such data are often used to guide selection of positive end-expiratory pressure (PEEP)/tidal volume combinations. Dynamic pressure-volume (DPV) curves obtained during tidal ventilation are effortlessly displayed on modern mechanical ventilator monitors and bear a theoretical but unproven relationship to the more labor-intensive SPV curves. OBJECTIVE: Attempting to relate the SPV and DPV curves, we assessed both curves under a range of conditions in a canine oleic acid lung injury model. METHODS: Five mongrel dogs were anesthetized, paralyzed, and monitored to assure a stable preparation. Acute lung injury was induced by infusing oleic acid. SPV curves were constructed by the super-syringe method. DPV curves were constructed for a range of PEEP and inspiratory constant flow settings while ventilating at a frequency of 15 breaths/min and tidal volume of 350 mL. Functional residual capacity at PEEP = 0 cm H2O was measured by helium dilution. The change in lung volume by PEEP at 8, 16, and 24 cm H2O was measured by respiratory inductance plethysmography. RESULTS: The slope of the second portion of the DPV curve did not parallel the corresponding slope of the SPV curve. The mean lower inflection point of the SPV curve was 13.2 cm H2O, whereas the lower inflection point of the DPV curve was related to the prevailing flow and PEEP settings. The absolute lung volume during the DPV recordings exceeded (p < 0.05) that anticipated from the SPV curves by (values are mean +/- SEM) 267 +/- 86 mL, 425 +/- 129 mL, and 494 +/- 129 mL at end expiration for PEEP = 8, 16, and 24 cm H2O, respectively. CONCLUSIONS: The contours of the SPV curve are not reflected by those of the DPV curve in this model of acute lung injury. Therefore, this study indicates that DPV curve should not be used to guide the selection of PEEP/tidal volume combinations. Furthermore, an increase in end-expiratory lung volume occurs during tidal ventilation that is not reflected by the classical SPV curve, suggesting a stable component of lung volume recruitment attributable to tidal ventilation, independent of PEEP.