Determining respiratory system resistance and reactance by impulse oscillometry in obese individuals

Objective:

To evaluate peripheral respiratory system resistance and reactance (Rrs and Xrs, respectively) in obese individuals.

Methods:

We recruited 99 individuals, dividing them into four groups by body mass index (BMI): < 30.0 kg/m² (control, n = 31); 30.0-39.9 kg/m² (obesity, n = 13); 40.0-49.9 kg/m² (severe obesity, n = 28); and ≥ 50.0 kg/m² (morbid obesity, n = 13). Using impulse oscillometry, we measured total Rrs, central Rrs, and Xrs. Peripheral Rrs was calculated as the difference between total Rrs and central Rrs. All subjects also underwent spirometry.

Results:

Of the 99 individuals recruited, 14 were excluded because they failed to perform forced expiratory maneuvers correctly during spirometry. The individuals in the severe obesity and morbid obesity groups showed higher peripheral Rrs and lower Xrs in comparison with those in the two other groups.

Conclusions:

Having a BMI ≥ 40 kg/m² was associated with a significant increase in peripheral Rrs and with a decrease in Xrs.     

脉冲振荡法在阻塞性通气功能障碍评定中的价值

目的 探讨脉冲振荡法评定阻塞性通气功能障碍的应用价值及其与常规肺通气功能测定的关系.方法 2007年11月至2008年5月,采用德国耶格公司的肺功能仪及产品说明书给出的预计值公式,测定100例(男72例,女28例)门诊和住院患者的FEV1、FVC、5 Hz时气道阻力(R5)、20 Hz时气道阻力(R20)、结构参数图中的中心阻力(Rc)和周边阻力(Rp)的实测值,FEV1、R5和R20占预计值%,以及FEV1/FVC等指标.并对常规和脉冲振荡法测定肺通气功能的指标进行相关分析.结果 所有受试者均获得满意的脉冲振荡测定结果.当FEV1/FVC低于正常时(＜70%),R5和Rp明显升高至(5.3±2.1)和(6.2±2.9)cm H2O·L-1·S-1(1 cm H2O=0.098 kPa),FEV1与R5、Rp呈显著负相关(r值分别为-0.38和-0.47,均P＜0.01),FVC与R5、Rp也呈显著负相关(r值分别为-0.28和-0.37,均P＜0.01).FEV1占预计值%、FVC占预计值%、FEV1/FVC与R5占预计值%均呈显著负相关(r值分别为-0.49、-0.39和-0.43,均P＜0.01).结论 脉冲振荡法的测定指标可用于评估阻塞性通气功能障碍,尤其是R5的诊断价值最大,并且与常规肺通气功能指标之间有良好的相关性.     

呼出气一氧化氮在支气管哮喘中的变化及与肺功能的相关性

目的 探讨呼出气一氧化氮(FENO)在哮喘各期中的变化及与肺功能的关系.方法 对急性发作期、慢性持续期、临床缓解期共计54例哮喘患者及19例健康人进行FENO、第1秒用力呼气量( FEV1)检测.结果 FENO、FEV1在哮喘急性发作期[(57.59±32.24)ppb和(1.72±0.33)L]、慢性持续期[(40.02±15.68)ppb和(2.41±0.23)L]、缓解期[(26.71±6.07)ppb和(2.82±0.29)L]及对照组[(14.74±3.42)ppb和(2.93±0.13)L]之间比较,除FEV1在缓解期与对照组比较差异无统计学意义(P＞0.05)外,差异均有统计学意义(F=19.555,163.096,P＜0.01).急性发作期FENO与FEV1之间存在负相关(r=-0.666,P=0.005),慢性持续期(r=-0.288,P=0.176)及缓解期(r=-0.246,P=0.457)的FENO与FEV1无相关性.结论 支气管哮喘患者FENO值增高,可用于评估哮喘的控制程度.     

Impulse oscillometry and spirometry exhibit different features of lung function in bronchodilation

Objective: Bronchodilator responses (BDRs) from impulse oscillometry (IOS) are not interchangeable with those from spirometry. We aimed to identify the characteristics of children with small airway hyperresponsiveness and to determine whether BDR from IOS provides an important supplement to BDR from spirometry. Methods: The records of 592 children with asthma or suspected asthma who underwent spirometric and oscillometric BDRs were retrospectively reviewed. Oscillometric BDR was defined as positive when relative or absolute changes of Rrs₅ or Xrs₅ were beyond two standard deviations and spirometric BDR as positive when absolute change of forced expiratory volume in one second (FEV₁) was ≥12%. Subjects were classified as positive for spirometric BDR only, positive for oscillometric BDR only, positive for both BDRs, or negative for both BDRs. Results: The results indicated that 101 (17.6%) subjects were positive for spirometric BDR only, 49 (8.5%) positive for oscillometric BDR only, 48 (8.3%) positive for both BDRs, and 377 (65.6%) negative for both BDRs. The agreement between spirometric and oscillometric BDRs was poor. Baseline FEV₁, Rrs₅, and Xrs₅ values strongly influenced the BDRs. Subjects positive for oscillometric BDR only were found to be younger than those positive for spirometric BDR only (P < 0.001). Subjects positive for both BDRs were more likely to have asthma, atopic dermatitis, wheezing apart from cold, or decreased baseline lung function relative to those positive in either test (P < 0.001). Conclusions: There was a low concordance between spirometric and oscillometric BDRs. Use of IOS to detect small airway hyperresponsiveness may add more information about a clinical profile of subjects with asthma.     

容积二氧化碳图对支气管哮喘患者急性加重分级的意义

目的 探讨容积二氧化碳图(Vcap)参数对支气管哮喘(简称哮喘)诊断的临床价值.方法 2006年7月至2007年5月对64例哮喘急性发作期患者(哮喘组)及20名健康者(健康对照组)进行肺通气功能以及Vcap测定,并依据FEV,占预计值%将哮喘患者分为A组(＞80%,18例)、B组(40%～80%,26例)、c组(＜40%,20例),所有受试者先行Vcap测定,随后完成FEV1占预计值%、FEV1/FVC、FVC占预计值%、最大呼气中段流量(MMEF)占预计值%测定.统计学处理采用SPSS 13.0软件.计量资料采用-x±s表示,计数资料采用卡方检验,计量资料两组间比较采用t检验.肺通气参数与Vcap参数间的相关性采用一元线性回归检验;哮喘组与对照组间的差异采用独立样本t检验;健康对照组及哮喘各亚组间的比较采用单因素方差分析.结果 哮喘组患者FEV1占预计值%、FEV1/FVC、PEF占预计值%、MMEF占预计值%分别为(52±20)%、(50±10)%、(49±16)%、(28±16)%,与健康对照组[(98±9)%、(80±6)%、(91±15)%、(73±7)%]比较差异有统计学意义(t值分别为6.93～13.29,P均＜0.01);哮喘组患者Ⅱ期斜率(dC2/DV)、Ⅲ期斜率(dC3/DV)、Ⅲ期与Ⅱ期斜率之比(SR23)分别为(19±6)%/L、(2.9±1.2)%/L、(16.8±10.6)%,与健康对照组[(31±8)%/L、(1.0±0.4)%/L,(3.3±1.5)%]比较差异有统计学意义(t值分别为5.09、-6.14、-6.54,P均＜0.01);哮喘B、C组dC2/DV分别为(17±5)%/L、(13±4)%/L,与健康对照组[(31±8)%/L]比较差异有统计学意义(t=-11.82、-16.75,P均＜0.01);哮喘B、C组患者dC3/DV、SR23分别为(3.2±0.8)%/L、(17.2±3.5)%,(4.1±1.2)%/L、(28.3±6.9)%,与健康对照组[(1.0±0.4)%/L、(3.3±1.5)%]比较差异有统计学意义(t值分别为2.16～26.08,P均＜0.01);哮喘A、B、C组间dC3/DV、SR23比较差异有统计学意义(t值分别为0.91～22.18,P均＜0.05);相关分析结果表明dC2/DV与FEV1占预计值%、FEV1/FVC、PEF占预计值%、MMEF占预计值%呈正相关(r值分别为0.69、0.54、0.59、0.54,P均＜0.01);dC3/DV与FEV1占预计值%、FEV1/FVC、PEF占预计值%、MMEF占预计值%呈显著负相关(r值分别为-0.62、-0.45、-0.69、-0.58,P均＜0.01);SR23与FEV1占预计值%、FEV1/FVC、PEF占预计值%、MMEF占预计值%呈显著负相关(r值分别为-0.75、-0.52、-0.74、-0.62,P均＜0.01).结论 Vcap是一种简便易行、可定量评估哮喘患者支气管阻塞严重程度的有效方法.     

ADAM33基因Met764Thr位点多态性与支气管哮喘发病及患者肺功能的相关性

目的探讨中国华南地区汉族人群ADAM33基因Met764Thr位点多态性与支气管哮喘（简称哮喘）及其患者肺功能的相关性。方法对164例中国华南汉族哮喘患者（哮喘组）及112名汉族健康者（健康对照组），应用聚合酶链反应和限制性片段长度多态性（PCR-RFLP）、DNA测序及肺功能测定的方法。结果（1）不同种族人群ADAM33基因Met764Thr位点等位基因频率的比较差异无统计学意义（χ^2=6．77，P〉0．05）；（2）ADAM33基因Met764Thr位点3种基因型（Met764／Met764、Met764／Thr764、Thr764／Thr764）在哮喘组分布频率分别为78．7％（129／164）、18．3％（30／164）、3．0％（5／164）；健康对照组分布频率分别为91．1％（102／112）、6．3％（7／112）、2．7％（3／112）；各基因型分布频率哮喘组与健康对照组比较差异有统计学意义（χ^2=8．46，P〈0．05）。ADAM33基因Met764Thr位点，Thr764等位基因在哮喘组与健康对照组分布频率分别为0．122、0．058，哮喘组与健康对照组Met764及，Thr764等位基因频率比较差异有统计学意义（χ^2=6．27，P〈0．05）；（3）单变量Logistic回归分析Met764Thr位点基因多态性与哮喘的关系表明，相对Met764／Met764基因型而言，Met764／Thr764杂合型与Met764／Thr764＋Thr764／Thr764基因型均能显著增加哮喘发生的危险性[OR值及95％可信区间（CI）分别为3．389（1．430～8．030）、2．767（1．308～5．854），P均〈0．05]；（4）在哮喘组中3种基因型的用力肺活量（FVC）实测值／预测值％、第一秒用力呼气容积（FEV1）实测值／预测值％水平比较差异有统计学意义（F值分别为0．49、5．17，P均〈0．05）。结论ADAM33基因Met764Thr位点基因多态性与中国华南汉族人群哮喘发病及患者的肺功能相关。     

健康中老年人肺功能下降与呼吸中枢驱动变化的关系

目的 探讨健康中老年人肺功能下降与呼吸中枢驱动变化的关系. 方法 随机选择8例健康中老年人及8例性别匹配的健康青年人,平均年龄分别为(57.3±5.0)岁和(28.3±3.4)岁,检测其肺功能.同时,通过多导食道电极记录膈肌肌电反映呼吸中枢驱动,观察静息状态下及最大用力吸气时的膈肌肌电. 结果 中老年组平均肺活量(VC)(3.2±0.5)L,显著低于青年组(4.0±0.8) L(t=-2.27,P＜0.05)；中老年人最大用力吸气动作时的膈肌肌电与青年人相似,分别为(172.2±54.6)μV与(175.0±55.7)μV(t=- 0.10,P=0.921)；中老年人安静状态下的潮气量及每分通气量与青年人相似,但其呼吸中枢驱动占最大值的百分数显著高于青年人,分别为( 27.8+12.9)％与(16.4±7.2)％(t=2.18,P＜0.05):中老年人呼吸中枢驱动有效性比青年人小1倍,分别为(62.7±23.2)％与(128.6±96.2)％. 结论 中老年人的呼吸中枢驱动储备低于青年人,肺功能随增龄减退并不是因为呼吸中枢驱动下降,而可能是因为肺结构本身改变所致.     

气道反应性监测对支气管哮喘联合治疗方案调整的指导意义

目的监测支气管哮喘（简称哮喘）患者联合治疗过程中症状积分、气道反应性[（以比气道传导率下降35％的乙酰甲胆碱浓度（PC35sGaw）为代表）]、第一秒用力呼气容积占预计值百分比（FEV1占预计值％）和呼气峰流量占预计值百分比（PEF％）的动态变化，探讨上述指标对评估病情、调整治疗方案的指导意义。方法将65例轻至中度慢性持续期哮喘患者分为A（22例）、B（22例）、C（21例）3组。初始治疗均为吸入糖皮质激素（ICS）＋长效β2受体激动剂（LABA）联合治疗[即沙美特罗／氟替卡松50μg／250μg、50μg／100μg]。A组维持固定剂量不变，B组根据哮喘症状积分和肺功能进行降级或停药，C组根据症状积分、肺功能结合气道反应性进行降级或停药。定期随访18个月，记录哮喘症状积分，测定FEV1占预计值％、PEF％和PC35sGaw。比较3种疗法的哮喘控制率。结果65例轻至中度哮喘患者中有46例按研究方案完成治疗和随访，其中A、B、C组分别为15、15、16例。哮喘患者症状积分、FEV1占预计值％和PEF％在治疗后1～3个月内明显改善，与治疗前比较差异有统计学意义（t值分别为9．54、13．17、14．27、12．4、6．72、6．59、8．31、5．22、5．96，P均〈0．01）。继续治疗期间大多数患者症状积分、FEV1占预计值％和PEF％维持在一相对稳定水平，持续性改善不明显，但B组部分患者症状控制不良，肺功能指标有所下降。气道反应性在治疗1～3个月内迅速降低（A、B、C组的t值分别为9．71、12．04、14．31，P均〈0．01），随后缓慢降低，治疗9个月后维持在较低水平。4例患者气道反应性阴转，其中1例在停药后又转为轻度阳性。疗程结束时A组哮喘控制率为93．3％。B组有86．7％的患者降级治疗，40％停药，但有40％需要复治或重新升级治疗。疗程结束时B组哮喘控制率为53．3％，与A组比较差异有统计学意义（χ^2=10．35，P〈0．01）。C组降级和停药的比例（62．5％、25％）低于B组，时间也晚于B组，但仅有1例需要复治，临床结束时哮喘控制率为93．8％（与A组相似），与B组比较差异有统计学意义（χ^2=10．35，P〈0．01）。结论（1）ICS联合LABA治疗能够迅速控制哮喘患者症状，改善肺功能，降低气道反应性；（2）根据哮喘临床控制水平调整治疗方案可能导致降级和停药过早，哮喘易于复发；（3）PC35sGaw是反映哮喘气道炎症较为敏感的指标，可作为评价疗效、指导治疗方案调整的指标之一。     

1988年上海地区成人肺功能正常预计值公式的适用性检验

目的 调查上海地区健康人群的肺功能情况,验证1988年成人肺功能正常预计值公式在现阶段的适用性.方法 选取2009年6月至2010年2月的健康体检者,对合格人群进行肺功能测定.根据1988年肺功能正常预计值公式判断结果,以肺功能正常:基本正常为2∶1的比例入选360例受试者,年龄19～83岁,平均(42±12)岁,按年龄分为6组,每组60人,男女各半.收集14项肺功能参数:肺活量、功能残气量、肺总量、残气容积、残气容积/肺总量、FVC、FEV1、FEV1/FVC、呼气流量峰值、用力呼出 25%肺活量时呼气流量(FEF25%)、用力呼出50%肺活量时呼气流量(FEF50%)、用力呼出75%肺活量时呼气流量(FEF75%)、DLCO、每升肺泡容积的一氧化碳弥散量(KCO).采用多元回归分析,建立新的肺功能正常预计值公式.将受试者数据分别输入上述2种公式,得到2组肺功能参数的预计值,将各参数的实测值和新预计值进行拟合度检验,然后将2组预计值进行相关性分析和差异度比较.结果 新肺功能正常预计值公式中各参数的实测值和预计值非常接近,其中肺活量(L)分别为3.6±0.8和3.6±0.8,FVC(L)分别为3.5±0.9和3.5±0.8,FEV1(L)分别为3.0±0.8和3.0±0.7,FEV1/FVC(%)分别为83.8±3.1和83.3±2.6,呼气流量峰值(L/s)分别为7.7±1.9和7.5±1.6,FEF25%(L/s)分别为6.8±1.7和6.7±1.2,FEF50%(L/s)分别为4.0±0.8和3.9±0.7,FEF75%(L/s)分别为1.5±0.7和1.5±0.6,残气容积(L)分别为1.6±0.4和1.6±0.3,功能残气量(L)分别为2.8±0.4和2.9±0.4,肺总量(L)分别为5.0±1.0和5.0±0.9,残气容积/肺总量(%)分别为33.1±4.6和32.7±4.5,DLCO(ml·min-1·mm Hg-1,1 mm Hg=0.133 kPa)分别为21.2±5.0和21.2±4.3,KCO(ml·min-1·mmHg-1)分别为4.4±0.7和4.5±0.4,差异均无统计学意义(t值为-0.856～1.673,均P＞0.05),说明新预计值公式拟合良好.两组的12项肺功能参数(除外DLCO和KCO)预计值均呈正相关(r值为0.966～0.989,均P＜0.01),差异度均＜5%.结论 1988年上海地区成人肺功能正常预计值公式仍适用于现阶段人群.

Abstract：

Objective To collect current information of normal adult pulmonary function in Shanghai, and to verify the applicability of the prediction equations for pulmonary function parameters established in 1988.Methods Subjects who underwent routine physical check-up were initially screened in Zhongshan Hospital from Jun.2009 to Feb.2010.Those who met the enrollment criteria were asked to take pulmonary function tests.A total of 240 subjects with normal pulmonary function and 120 subjects with mild small airway abnormalities were enrolled in this study according to the prediction equations established in 1988.The age of these subjects ranged from 19 to 83 years old, with a mean age of (42 ± 12) years.All subjects were assigned into 6 groups according to their age, with 60 subjects (30 males, 30 females) in each group.Pulmonary function parameters were collected, including VC, FVC, FEV1, FEV1/FVC, PEF,FEF25%, FEF50%, FEF75%, RV, FRC, TLC, RV/TLC, DLCO and KCO.New prediction equations for the above 14 parameters were established by multiple regression analysis.The parameters of anthropometry were introduced into the new and the 1988 prediction equations to get 2 groups of prediction values.Comparison of variance and correlation analysis between the new and the old prediction values were conducted.Results New prediction equations for normal adult pulmonary function parameters in Shanghai were established.The actually measured parameters were very close to the predicted values:VC (L) 3.6 ±0.8 vs 3.6 ±0.8, FVC(L) 3.5 ±0.9 vs 3.5 ±0.8, FEV1(L) 3.0 ±0.8 vs 3.0 ±0.7, FEV1/FVC (%) 83.8 ±3.1 vs 83.3 ±2.6, PEF (L/s) 7.7 ±1.9 vs 7.5 ±1.6, FEF25% (L/s) 6.8 ±1.7 vs 6.7 ±1.2, FEF50% (L/s) 4.0±0.8vs3.9±0.7, FEF75%(L/s) 1.5±0.7vs1.5±0.6, RV(L) 1.6±0.4vs1.6±0.3, FRC (L) 2.8±0.44.4±0.7vs4.5 ±0.4 (t = -0.856- 1.673, all P＞0.05).Except DLCO and KCO, there was a significant positive correlation between each pair of the predicted values ( r =0.966 -0.989, all P ＜0.01 ),and the variance between each pair of predicted values was within 5%.Conclusion The prediction equations for normal adult pulmonary function parameters established in 1988 is still valid currently for the population in Shanghai.     

阻塞性睡眠呼吸暂停综合征患者肺功能与夜间低氧血症的关系

目的探讨睡眠呼吸暂停综合征（ＳＡＳ）患者体位及肥胖因素引起的肺功能改变与夜间低氧血症的关系。方法选择确诊为ＳＡＳ患者３４例，分别于坐位和仰卧位检查肺功能和血气分析，整夜多导睡眠仪监测。肺功能、血气指标和理想体重％（ＩＢＷ％）分别与呼吸暂停指数（ＡＩ）、＜９０％Ｔ（ＳａＯ２低于９０％时间占总睡眠时间百分比）进行相关分析。结果患者由坐位改为仰卧位，ＰａＯ２、肺活量（ＶＣ％）、补呼气量（ＥＲＶ）、功能残气量（ＦＲＣ％）、残气容积（ＲＶ％）、肺总量（ＴＬＣ％）均出现有统计学意义的降低。ＡＩ与仰卧位ＶＣ％、ＴＬＣ％呈正相关。＜９０％Ｔ与坐位ＰａＯ２、ＥＲＶ呈负相关。ＩＢＷ％与坐、仰卧位ＶＣ％和ＥＲＶ呈负相关，与坐位ＦＲＣ呈负相关。ＩＢＷ％与＜９０％Ｔ呈正相关。结论伴有肥胖的ＯＳＡＳ患者，体位改变及肥胖因素影响患者肺功能，加重呼吸暂停时的低氧血症     

Variable response to inhaled salbutamol of different lung function parameters in healthy children

We compared changes in different lung function parameters (airway conductance and forced expiration parameters) after inhalation of salbutamol in 49 healthy school children. Bronchomotor tone (expressed by sG_aw) was found to be reducible in 92% of the children. Changes in sG_aw after inhalation (mean 63.4%) were found to be highly significant (P < 0.001) and most sensitive in evaluating bronchodilatation, while changes in FEV₁ (mean 6.3%), PEFR (mean 5.8%) and FEF₇₅ (mean 5.9%) were of less or no significance. Large airway compression on forced expiration due to reduced airway wall rigidity after bronchodilation is a possible explanation of these results.     

Lung function in the absence of respiratory symptoms in overweight children and adolescents

OBJECTIVE:

To describe lung function findings in overweight children and adolescents without respiratory disease.

METHODS:

This was a cross-sectional study involving male and female overweight children and adolescents in the 8-18 year age bracket, without respiratory disease. All of the participants underwent anthropometric assessment, chest X-ray, pulse oximetry, spirometry, and lung volume measurements. Individuals with respiratory disease were excluded, as were those who were smokers, those with abnormal chest X-rays, and those with an SpO₂ = 92%. Waist circumference was measured in centimeters. The body mass index-for-age Z score for boys and girls was used in order to classify the individuals as overweight, obese, or severely obese. Lung function variables were expressed in percentage of the predicted value and were correlated with the anthropometric indices.

RESULTS:

We included 59 individuals (30 males and 29 females). The mean age was 11.7 ± 2.7 years. Lung function was normal in 21 individuals (35.6%). Of the 38 remaining individuals, 19 (32.2%), 15 (25.4%), and 4 (6.7%) presented with obstructive, restrictive, and mixed ventilatory disorder, respectively. The bronchodilator response was positive in 15 individuals (25.4%), and TLC measurements revealed that all of the individuals with reduced VC had restrictive ventilatory disorder. There were significant negative correlations between the anthropometric indices and the Tiffeneau index in the individuals with mixed ventilatory disorder.

CONCLUSIONS:

Lung function was abnormal in approximately 65% of the individuals evaluated here, all of whom were overweight. Obstructive ventilatory disorder and positive bronchodilator response predominated.     

脉冲振荡法在支气管舒张试验中的应用价值

为探讨脉冲振荡法在支气管舒张试验中的应用价值 ,采用脉冲振荡法测定了 2 1例哮喘发作期患者吸入支气管舒张剂前后呼吸阻抗的变化及改善率 ,同时测定肺通气功能变化及改善率 ,并对两种方法所测结果进行对比及相关性分析。结果显示 ,吸入沙丁胺醇后 5 Hz和 2 0 Hz振荡频率时粘性阻力 ( R5、R2 0 )、5 Hz振荡频率时电抗( X5)及共振频率 ( Fres)与用药前比较均明显改善 ( P<0 .0 1) ,其中以 Fres改善最明显 ;一秒钟用力呼气容积( FEV1 )、最大峰流速 ( PEF)、5 0 %和 2 5 %肺活量最大呼气流速 ( V50 、V2 5)均明显改善 ( P<0 .0 1) ;呼吸阻抗改善率显著高于肺通气功能改善率 ( P<0 .0 5 ) ;吸药后 FEV1 增加与 Fres、R5和 X5变化相关密切 ,相关系数分别为0 .69、0 .4 8和 - 0 .4 2。认为 ,脉冲振荡法用于支气管舒张试验是诊断、鉴别诊断支气管哮喘及观察药物疗效的有用工具 ,值得临床推广使用     

天津地区严重急性呼吸综合征患者康复10年后肺功能状态

目的 评估严重急性呼吸综合征(SARS)患者康复10年后的肺功能恢复状况及SARS对患者肺功能的影响.方法 对本院2003年确诊为SARS的25例康复患者进行肺功能检测,分别测定肺总量、残气量、肺活量、用力肺活量(FVC)、FEV1、FEV1/FVC和肺一氧化碳弥散量(DLCO),并与2003年初始恢复期的肺功能指标进行自身对比.25例中男3例,女22例,年龄31 ～ 69岁,平均(45.8±12.2)岁.选取同期25名健康成人体检者,男6名,女19名,年龄31 ～ 62岁,平均(42.3±11.9)岁,对二者的肺功能指标进行对比分析.结果 25例中单纯弥散障碍2例,单纯限制性通气功能障碍2例,弥散障碍合并限制性通气功能障碍11例,弥散障碍合并阻塞性通气功能障碍1例.肺功能无异常患者10例.10年后和10年前主要的肺功能指标DLCO为(73±12)％和(72±15)％,FEV1/FVC为(83±11)％和(85±7)％,FEV1为(88±7)％和(86±14)％,FVC为(87±21)％和(87±17)％、残气量为(100±17)％和(78±30)％,各项指标比较差异均无统计学意义(均P＞0.05),同时与健康体检者比较差异均无统计学意义(均P＞0.05).结论 SARS患者康复10年后肺通气功能基本恢复正常,肺功能损害以弥散及限制性通气功能障碍为特征.     

脉冲震荡法测定肺功能的应用现状及前景展望

脉冲震荡(impulse oscillometry,IOS)法在平静呼吸的基础上测量患者肺功能,无需患者特别配合,操作简单快捷,有广阔的应用前景.本文介绍了IOS技术的原理及临床应用现状,并重点探讨了其在临床应用中存在的一些问题.     

Pulmonary function in advanced uncomplicated singleton and twin pregnancy

Objective:

Pregnancy brings about significant changes in respiratory function, as evidenced by alterations in lung volumes and capacities, which are attributable to the mechanical impediment caused by the growing foetus. This study was undertaken in order to identify changes in respiratory function during normal pregnancy and to determine whether such changes are more pronounced in twin pregnancy than in singleton pregnancy.

Methods:

Respiratory function was assessed in 50 women with twin pregnancies and in 50 women with singleton pregnancies (during the third trimester in both groups), as well as in 50 non-pregnant women. We measured the following pulmonary function test parameters: FVC; FEV₁; PEF rate; FEV₁/FVC ratio; FEF_25-75%; and maximal voluntary ventilation.

Results:

All respiratory parameters except the FEV₁/FVC ratio were found to be lower in the pregnant women than in the non-pregnant women. We found no significant differences between women with twin pregnancies and those with singleton pregnancies, in terms of respiratory function.

Conclusions:

Despite its higher physiological demands, twin pregnancy does not appear to impair respiratory function to any greater degree than does singleton pregnancy.