哮喘和咳嗽变异性哮喘儿童肺常规通气功能的比较

目的：比较哮喘与咳嗽变异性哮喘（CVA）患儿肺常规通气功能的变化。方法：选择2010年 5月至2011年5月确诊为哮喘或CVA的患儿140例,分为哮喘急性发作组（发作组,50例）、哮喘缓解组（缓解组,50例）和CVA组（40例）;同期正常健康体检儿童30例作为对照组。测定4组儿童用力肺活量(FVC)、一秒钟用力呼气容积(FEV1)、最大呼气峰流速(PEF)、用力呼气25%流速(FEF25)、用力呼气50%流速(FEF50)、用力呼气75%流速(FEF75)、最大呼气中期流速(MMEF75/25)等7项肺功能指标。结果：发作组患儿各项肺功能指标如大气道指标FVC、FEV1、PEF、FEF25及小气道指标FEF50、FEF75、MMEF75/25的实际值/预计值平均水平均<80%,且以FEF50、FEF75、MMEF75/25等小气道指标下降为著。CVA组患儿小气道指标FEF75、MMEF75/25实际值/预计值的平均水平<80%。发作组各项肺常规通气功能指标均低于对照组;缓解组、CVA组FVC、FEV1、FEF25及 MMEF75/25实际值/预计值的平均水平低于对照组;发作组各项肺功能指标均明显低于缓解组和CVA组;CVA组与缓解组各项肺功能指标差异均无统计学意义。结论：哮喘急性发作期患儿存在大小气道功能障碍,以小气道功能障碍为主;CVA患儿以小气道功能轻微障碍为主,与哮喘缓解期相似。     

昆明市5~14岁儿童肺通气功能参数实测值与Zap

目的 研究昆明市5~14岁健康儿童肺通气功能主要参数实测值占Zapletal方程式预计值的百分比,为临床准确判断肺通气功能提供依据。方法 纳入昆明市5~14岁健康儿童702名,其中男352名,女350名。采用Jaeger肺功能仪测定用力肺活量（FVC）、第1秒用力呼气容积（FEV1）、1秒率（FEV1/FVC）、最大中期呼气流量（MMEF）、用力呼气25%肺活量时瞬时流量（FEF25）、用力呼气50%肺活量时瞬时流量（FEF50）、用力呼气75%肺活量时瞬时流量（FEF75）、最高呼气流量（PEF）、每分钟最大通气量（MVV）,共9项指标,以肺功能仪中提供的Zalpetal预计值公式得出的数值作为所选择儿童的预计值,计算其实测值占预计值的百分比。结果 在702名儿童中,肺通气功能主要参数PEF、FVC、FEV1、FEV1/FVC、MVV实测值占预计值百分比的均值分别波动于102%~114%、94%~108%、98%~113%、98%~107%、141%~183%。气道流速指标功能参数FEF25、FEF50、FEF75、MMEF实测值占预计值百分比分别波动于98%~116%、85%~102%、71%~98%、83%~100%。各参数PEF、FVC、FEV1、FEV1/FVC、MVV、FEF25、FEF50、FEF75、MMEF实测值占Zapletal方程式预计值百分比的下限分别为88.2%、88.4%、92.0%、94.4%、118.5%、82.9%、70.0%、62.1%、70.1%。结论 昆明地区5~14岁健康儿童肺通气功能参数水平与Zapletal方程式提供的正常值存在一定差异;该地区此年龄段的健康儿童肺通气功能参数PEF、FVC、FEV、FEV1/FVC、MVV、FEF25、FEF50、FEF75、MMEF实测值占预计值百分比的正常参考值下限可考虑分别设为88.2%、88.4%、92.0%、94.4%、118.5%、82.9%、70.0%、62.1%、70.1%。     

昆明市5~14岁儿童肺通气功能参数实测值与Zap

目的 研究昆明市5~14岁健康儿童肺通气功能主要参数实测值占Zapletal方程式预计值的百分比,为临床准确判断肺通气功能提供依据。方法 纳入昆明市5~14岁健康儿童702名,其中男352名,女350名。采用Jaeger肺功能仪测定用力肺活量（FVC）、第1秒用力呼气容积（FEV1）、1秒率（FEV1/FVC）、最大中期呼气流量（MMEF）、用力呼气25%肺活量时瞬时流量（FEF25）、用力呼气50%肺活量时瞬时流量（FEF50）、用力呼气75%肺活量时瞬时流量（FEF75）、最高呼气流量（PEF）、每分钟最大通气量（MVV）,共9项指标,以肺功能仪中提供的Zalpetal预计值公式得出的数值作为所选择儿童的预计值,计算其实测值占预计值的百分比。结果 在702名儿童中,肺通气功能主要参数PEF、FVC、FEV1、FEV1/FVC、MVV实测值占预计值百分比的均值分别波动于102%~114%、94%~108%、98%~113%、98%~107%、141%~183%。气道流速指标功能参数FEF25、FEF50、FEF75、MMEF实测值占预计值百分比分别波动于98%~116%、85%~102%、71%~98%、83%~100%。各参数PEF、FVC、FEV1、FEV1/FVC、MVV、FEF25、FEF50、FEF75、MMEF实测值占Zapletal方程式预计值百分比的下限分别为88.2%、88.4%、92.0%、94.4%、118.5%、82.9%、70.0%、62.1%、70.1%。结论 昆明地区5~14岁健康儿童肺通气功能参数水平与Zapletal方程式提供的正常值存在一定差异;该地区此年龄段的健康儿童肺通气功能参数PEF、FVC、FEV、FEV1/FVC、MVV、FEF25、FEF50、FEF75、MMEF实测值占预计值百分比的正常参考值下限可考虑分别设为88.2%、88.4%、92.0%、94.4%、118.5%、82.9%、70.0%、62.1%、70.1%。     

Adverse pulmonary responses to aspirin and acetaminophen in chronic childhood asthma

Because aspirin (ASA) is often reported to have an adverse effect on pulmonary function in children with chronic asthma, acetaminophen is commonly used as an ASA substitute in these children. To study acetaminophen effects on pulmonary functions, double-blind, oral challenges of ASA (600 mg), acetaminophen (600 mg), or lactose were administered on separate days to 25 chronic asthmatics, ten boys and 15 girls, ranging in age from 8 to 18 years (mean age +/- 1 SD: 12.5 +/- 2.8 years). No patient had a past history of adverse reactions to either drug. Forced expiratory volume in 1 second (FEV1), peak expiratory flow rate (PEFR), maximal mid-expiratory flow rate (FEF25-75), forced vital capacity (FVC), maximal voluntary ventilation (MVV), and flow volume curves were measured at base line and 1/2, 1, 2, 3, and 4 hours after ingestion of drug or placebo. Persistent decreases from base line FEV1 (greater than 20%) or FEF25-75 (greater than 30%) occurred in four ASA- and two acetaminophen-challenged patients. One ASA-sensitive patient was placebo intolerant; another reacted to acetaminophen. The acetaminophen responses were of less intensity than the ASA responses. Analysis of group mean pulmonary function responses to ASA, acetaminophen, and lactose showed no significant difference among the three agents at any time. Aspirin should be used cautiously in asthmatic children. Acetaminophen appears to be an adequate, although not completely, innocuous ASA substitute.     

What are the best pulmonary function test parameters for early detection of post‐lung transplant bronchiolitis obliterans syndrome in children?

Post-lung transplant bronchiolitis obliterans syndrome (BOS) is defined as an unexplained fall in forced expiratory volume in 1 s (FEV1) >or=20% of baseline (B). There have been reports in adults that FEF25-75% (>30% decline from B) is more sensitive than FEV1 for the early diagnosis of BOS. Yet, it is not known if other pulmonary function test (PFT) parameters - forced expiratory flow rates at 25-75% of vital capacity (FEF25-75%) and maximal expiratory flow rate at 80% (Vmax80%), 70% (Vmax70%) and 60% (Vmax60%) - are more sensitive indicators for early diagnosis of BOS than FEV1 in post-lung transplant children. We reviewed serial PFTs of 18 patients (ages 14.1 +/- 3.7 yr, 50% female) who had lung transplantation at our institution from 1993 to 1999, and who met the criteria for BOS diagnosis. There was no significant difference in post-transplant days when decline in FEV1 >or=20% of B, FEF25-75% >30% of B, and Vmax80%, Vmax70% and Vmax60% from normal occurred (635 +/- 431, 551 +/- 422 and 454 +/- 287 days, respectively; p = 0.4). However, a decline in FEV1 was the first abnormality in only 39% of the patients, while a decline in FEF25-75% and Vmax at specific lung volume were the first abnormality in 78% and 56% of the patients, respectively. The earliest signs of BOS would be missed in 61% of patients if FEV1 was the primary parameter used for the diagnosis. In order to improve the sensitivity of the diagnosis of post-lung transplant BOS; we speculate that the diagnosis should be based on decreases in FEF25-75% rather than on FEV1.     

Impact of acute chest syndrome on lung function of children with sickle cell disease

OBJECTIVE: To test the hypothesis that children with sickle cell disease (SCD) who experienced an acute chest syndrome (ACS) hospitalization episode would have worse lung function than children with SCD without ACS episodes. STUDY DESIGN: Forced expiratory volume in 1 second (FEV(1)); forced vital capacity (FVC); FEV(1)/FVC ratio; peak expiratory flow (PEF); forced expiratory flow at 25% (FEF(25)), 50% (FEF(50)), and 75% (FEF(75)) of FVC; airway resistance (Raw); and lung volumes were compared in 20 children with ACS and 20 aged-matched children without ACS (median age, 11 years; range, 6 to 16 years). Fourteen age-matched pairs were assessed before and after bronchodilator use. RESULTS: The mean Raw (P = .03), TLC (P = .01), and RV (P = .003) were significantly higher in the group with ACS than in the group without ACS. There were no significant differences in the changes in lung function test results in response to bronchodilator administration between the 2 groups, but the children with ACS had a lower FEF(25) (P = .04) and FEF(75) (P = .03) pre-bronchodilator use and a lower mean FEV(1)/FVC ratio (P = .03) and FEF(75) (P = .03) post-bronchodilator use. CONCLUSIONS: Children with SCD who experienced an ACS hospitalization episode had significant differences in lung function compared with those who did not experience ACS episodes. Our results are compatible with the hypothesis that ACS episodes predispose children to increased airway obstruction.     

Effects of passive smoking on lung function in children

BACKGROUND: Passive smoking can have significant effects on lung function with reductions in forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and forced mid-expiratory flow rate (FEF25-75%) of between 5 and 10%. METHODS: Fifty non-smoking children aged 6-15 years, who had no history of asthma or atopy and no parental history of atopy, were assessed with respect to their lung functions (FEV1, FEV1/FVC, FEF25-75%). RESULTS: Thirty-three of these children were being exposed to environmental tobacco smoke inside their homes, while 17 children were not exposed. In the 'passive smoker' group the FEV1, FEV1/FVC and FEF25-75% values were found to be significantly lower than the non-smoker control group's values (P = 0.0080, 0.0228 and 0.0003, respectively). The decrease in FEF25-75% was significantly correlated inversely with the number of cigarettes smoked per day (P = 0.0261). CONCLUSION: There is sufficient evidence to support the notion that environmental tobacco smoke is a serious health burden for children. Considering that recent studies suggest that up to 70% of children grow up in homes with at least one smoker, every effort should be made to reduce these children's exposure to environmental tobacco smoke and to give them a chance to grow up in a more healthy environment.     

新生儿机械通气后远期肺功能随访

目的　了解新生儿机械通气对远期肺功能及反复呼吸道疾病影响。方法　新生儿期用呼吸机治疗16例患儿 ,8年后对其进行随访 ,并作肺功能检测。结果　 5 0 %患儿有反复呼吸道疾病症状 ,75 %患儿肺功能异常 ,其中残气量 /肺总量 (RV/TLC)为 5 6 .2 5 %、肺活量 2 5 %时最大呼气流量 (Vmax 2 5 )为 4 3.7%、特殊呼吸道阻力 (sRaw)及特殊呼吸道传导 (sGaw)均为 5 0 %。吸气峰压 (PIP) >2 5cmH2 O组用力肺活量中期平均呼气流速 (FEF 2 5 %～ 75 % )及 5 0 %用力肺活量时的最大呼气流速 (Vmax 5 0 )低于PIP <2 5cmH2 O组。呼气末正压 (PEEP)≤ 4cmH2 O组sRaw >4cmH2 O组。结论　新生儿机械通气可影响远期肺功能。较高PIP或过低PEEP可引起肺损伤 ,从而引起呼吸道阻力增加 ,呼吸道高反应。而儿童期反复呼吸道疾病可能与肺损伤后支气管反应性增高有关     

Status asthmaticus in children: a one-year study.

50 children were admitted on 72 occasions during one year in status asthmaticus, defined as wheezing not relieved by two doses of bronchodilator 4 hours apart. At least one-third of children were hypercapnoeic on admission. They were managed with either oral prednisolone and nebulised salbutamol. Those with peak expiratory flow rates of greater than 25% expected for height were satisfactorily managed on the oral regimen. One child needed assisted ventilation. 73% were fit for discharge within 4 days and more than half of them needed a change in maintanance treatment.     

Reduction in pulmonary function and increased frequency of cough associated with passive smoking in teenage athletes

Previous studies have suggested that passive smoking (involuntary inhalation of tobacco smoke by nonsmokers) reduces small airways function. We evaluated the exposure to passive smoking and its effects on pulmonary function and symptoms in a group of 12- to 17-year-old high school athletes (N = 209; 119 boys and 90 girls) at their annual presport participation physical examinations. A structured interview was used to assess pulmonary symptoms, personal smoking habits, and passive cigarette smoke exposure. All athletes performed forced expiratory maneuvers on a portable spirometer. We measured forced vital capacity, forced expiratory volume in 1 second, and forced expiratory flow 25% to 75% (FEF25-75). The best of three FEF25-75 measured was used. Less than 70% of predicted FEF25-75 was considered abnormal. Of the 209 athletes, 7.7% were active smokers and were excluded. Of the remaining 193 athletes, 68.4% were currently exposed to passive smoking. We found a fourfold increase in incidence of low FEF25-75 and/or cough in athletes exposed to passive smoking compared with athletes not exposed: 18 of 132 exposed athletes (13.6%) had low FEF25-75 and/or cough compared with two of 61 unexposed athletes (3.3%) who had low FEF25-75 and cough (P = .02). Boys were more frequently exposed to passive smoking than girls (74% of boys [80/108] v 61% of girls [52/85] ), but the effects were more pronounced in girls. These data show a relationship between exposure to passive smoking and early pulmonary dysfunction in young athletes. The frequent exposure to passive smoke and the high prevalence of dysfunction in this population, generally considered to be healthy, is of particular concern.     

Risk factors for reduced lung function in Australian Aboriginal children

AIM: To determine the influence of perinatal and childhood exposures on lung function in a cohort of Australian Aboriginal children. METHODS: This was a cross-sectional study of 547 Northern Territory Aboriginal children, aged 8-14 years, belonging to a birth cohort. Assessment included physical examination and spirometry as well as retrospective review of centralised hospital records. The effect of select perinatal and childhood exposures on lung function outcomes (forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and forced expiratory flow between 25 and 75 s (FEF25-75)) adjusted for age, sex, height and other measures of size was examined using multiple regression. RESULTS: Non-urban residence (FEV1 -5% (95% confidence interval, CI 0.91-0.99), FVC -9% (95% CI 0.87-0.95)), current cough (FEV1 -6% (95% CI 0.91-0.97), FVC -4% (95% CI 0.93-0.97), FEF25-75 -8% (95% CI 0.86-0.98)) and hospitalisations for respiratory disease (FEV1 -10% (95% CI 0.86-0.95), FEF25-75 -12% (95% CI 0.70-0.87)) all had significant negative effects on adjusted lung function measures. Children with a non-Aboriginal ancestor had significantly better lung function. No perinatal exposure other than neonatal lung disease had any significant effect on adjusted lung function. CONCLUSIONS: For Northern Territory Aboriginal children factors related to the childhood environment are more important than perinatal factors in determining childhood lung function.     

Role of conventional physiotherapy in cystic fibrosis

Because of the time and the emotional cost involved in performing daily conventional chest physiotherapy in patients with cystic fibrosis, a 3-year prospective study was undertaken to compare the long-term effects of postural drainage accompanied by percussion and the forced expiratory technique with the effects of the forced expiratory technique alone. Patients who performed the forced expiratory technique alone had mean annual rates of decline that were significantly different from zero for forced expiratory volume in 1 second (p less than 0.001), forced expiratory flow between 25% and 75% of vital capacity (p less than 0.001), and Shwachman clinical score (p less than 0.004). In the group performing conventional physiotherapy with percussion and postural drainage, only the mean annual rate of decline for forced expiratory flow between 25% and 75% of vital capacity was significantly different from zero (p less than 0.03), and it was significantly different from the mean rate of decline associated with the forces expiratory technique alone (p less than 0.04). We conclude that conventional chest physiotherapy should remain a standard component of therapy in cystic fibrosis.     

Low-density areas on high-resolution computed tomograms in chronic pediatric asthma

OBJECTIVE: In children with chronic persistent asthma, we evaluated whether the presence of increased residual volume (RV) after anti-inflammatory treatment correlates with the detection of low-density areas on high-resolution computed tomography (HRCT), similar to those in emphysema. METHODS: Children with a confirmed diagnosis of asthma (n = 32) were enrolled in a prospective study. All patients had reduction of airflow in the peripheral airways, increased RV, and increased serum eosinophil cationic protein (ECP) values indicating airway inflammation. All the children were treated with salmeterol (50 microg twice daily) and fluticasone (250 microg twice daily) for a 3-month period. RESULTS: At the end of treatment, peripheral eosinophil counts, serum ECP, forced expiratory volume in 1 second (FEV(1)), mean forced expiratory flow during the middle half of forced vital capacity (FEF(25-75)), RV, and total lung capacity values improved in all the patients. HRCT was normal in 22 children (68.8%); in the remaining 10 subjects, low-density areas were found despite normalization of FEV(1), FEF(25-75), and significant reduction in ECP. A significant correlation was found between persistence of RV values >150% predicted and the presence of low-density areas on HRCT (r = 0.84, P <.0001). CONCLUSIONS: Structural changes similar to emphysema are also present in asthmatic children. Our findings suggest that the persistence of increased RV may be used to identify subjects with low-density areas on HRCT.     

第1秒用力肺活量、用力肺活量及1秒率正常的支气管哮喘患儿支气管舒张试验结果分析

目的评估肺通气功能中第1秒用力肺活量(FEV₁)、用力肺活量(FVC)及1秒率(FEV₁/FVC)正常的支气管哮喘(哮喘)患儿支气管舒张试验(BDT)阳性率,提高对FEV₁、FVC及FEV₁/FVC正常的哮喘患儿完善BDT检查重要性的认识。方法选择2018年9月至2019年8月山东大学附属省立医院门诊诊断为哮喘的患儿,年龄5~14岁,可配合肺通气功能及BDT检查,收集FEV₁、FVC及FEV₁/FVC正常的患儿肺功能资料,统计BDT阳性率并分析小气道功能状况。结果共纳入FEV₁、FVC及FEV₁/FVC正常的患儿1 631例,其中肺通气功能正常1 414例,小气道功能障碍217例。吸入支气管扩张剂15 min后,BDT阳性哮喘患儿共127例,阳性率为7.8%;男87例,女40例,其中合并小气道功能障碍患儿BDT阳性62例,BDT阳性率为28.6%。FEV₁改善率在8.0%~11.9%有132例(8.1%)。用药前FEV₁占预计值的百分比为(98.5±10.3)%;吸入硫酸特布他林15 min后,改善率为13.5%(12.5%,16.2%)。用力呼出50%肺活量的瞬间呼气流量(FEF50)、用力呼出75%肺活量的瞬间呼气流量(FEF₇₅)、最大呼气中期流量(MMEF)改善率与其基础值呈负相关[FEF50(r=-0.339,P<0.01)、FEF₇₅(r=-0.400,P<0.01)、MMEF(r=-0.375,P<0.01)];FEV₁改善率与FEV₁基础值无显著相关(r=-0.128,P=0.153),FEV₁改善率与MMEF基础值呈负相关(r=-0.231,P<0.01)。结论有部分哮喘患儿在FEV₁、FVC及FEV₁/FVC正常范围时BDT阳性。建议对症状典型或不典型哮喘患儿在诊断及随访时尽可能完善BDT检查,以明确诊断以及获取当前个人最佳值,同时结合小气道功能有助于全面评估哮喘病情及控制情况。     

肥胖对不同年龄段哮喘患儿肺功能的影响

目的研究肥胖对不同年龄段初诊哮喘患儿肺功能的影响。方法 294名初诊哮喘患儿按年龄分为学龄前期组(6岁)及学龄期组(6~12.5岁),并根据不同体重指数(BMI)分为体重正常哮喘组、超重哮喘组及肥胖哮喘组,检测患儿肺功能,包括大气道通气功能指标[用力肺活量(FVC)、第1秒用力呼气量(FEV1)]和小气道通气功能指标[用力呼气25%、50%及75%流量的实测值占预计值的百分比,即MEF25%、MEF50%、MEF75%]。结果在校正了性别及BMI分组因素后,学龄期组FEV1%、MEF25%、MEF50%低于学龄前期组(P0.05)。两年龄组正常体重患儿间比较,学龄期组基础肺功能FEV1%、MEF25%、MEF50%低于学龄前期组(P0.05);两年龄组超重患儿间比较,学龄期组FVC%及MEF50%低于学龄前期组;两年龄组肥胖患儿间比较,肺功能各指标差异均无统计学意义。学龄前期肥胖组FVC%、FEV1%及MEF75%均低于体重正常组,而学龄期肥胖组仅FVC%和FEV1%与体重正常组间差异有统计学意义(P0.05)。结论肥胖对哮喘患儿基础肺功能的影响存在年龄差异,于学龄前期更明显。     

Optimal level of physical activity in children with chronic lung diseases

Aim: To determine the optimal level of physical activity and its relationship with disease severity in children with chronic lung diseases (CLD). Methods: Pulmonary function and exercise tests were compared between 18 CLD children (aged 13.5 ± 2.4 years, 33% male) and 18 healthy controls without any history of lung diseases (age and sex matched). Results: CLD children had lower forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV)₁, forced expiratory flow rate between 25% and 75% of vital capacity (FEF)_25–75% and total lung capacity (TLC) and higher residual volume (RV)/TLC ratio than controls (77.3 ± 22.6 vs. 97.9 ± 12.5%pred; p = 0.002, 74.3 ± 17.6 vs. 104.0 ± 12.6%pred; p < 0.001, 49.9 ± 23.1 vs. 75.6 ± 18.6%pred; p < 0.001, 82.8 ± 18.6 vs. 95.6 ± 9.8%pred; p = 0.04, 30.8 ± 10.2 vs. 24.4 ± 5.9%; p = 0.04, respectively). Oxygen consumption at anaerobic threshold (AT) and optimal level of physical activity (metabolic equivalents [METs] at AT) were not different between the two groups and between mild and moderate to severe CLD. However, when the exercise was continued beyond the AT, CLD children demonstrated poorer exercise performance than normal controls. Conclusion: Children with CLD demonstrated the same level of optimal physical activity as normal children despite their lower lung function. The optimal level of physical activity was not related to disease severity. The exercise test and exercise should not be performed beyond the AT by the CLD children. Proper exercise test should be done to determine their optimal exercise activity.     

Prevention of cross infection during outpatient spirometry

Lung function apparatus may be a source of cross infection in patients with cystic fibrosis and may be prevented using a 'bag in bottle' system. As this system has never been validated in children the flow volume loops performed using a Vitalograph Compact in the usual way were compared with results obtained blowing into the bag and bottle system, in random order, in 20 children with asthma (age 8-15 years). Three reproducible flow volume loops were recorded for each apparatus. There was no order effect. Mean (SE) results for forced expiratory volume in one second, forced vital capacity (FVC), peak expiratory flow rate, and maximum expiratory flow at between 75% and 25% of FVC showed respectively that the bag in bottle results were significantly greater than those obtained blowing directly into the spirometer by 90 (17) ml, 12.7 (5.1) l/min, 130 (60) ml/min. Although statistically significant, these differences are within the previously described coefficients of variation for children with cystic fibrosis and are of doubtful clinical relevance. It is concluded that the bag in bottle system does not introduce any important systematic error. It potentially offers absolute protection from cross infection.     

以胸闷为主诉的不典型支气管哮喘患儿激发试验前后的肺功能特点

目的 了解以胸闷为主诉的不典型支气管哮喘患儿在支气管激发试验前后的肺功能特点。方法 选取2010 年1 月至2013 年12 月在我院肺功能室进行支气管激发试验的不典型哮喘患儿34 例为研究对象(不典型哮喘组),同期选取典型哮喘患儿34 例为对照,检测不典型哮喘组患儿支气管激发试验前后的肺功能,以及典型哮喘组患儿发作期和缓解期肺功能。结果 不典型哮喘组激发前肺功能指标用力肺活量(FVC)、第1 秒最大呼气量(FEV1)、FEV1/FVC、呼气峰流速(PEF)、用力呼气25 %、50 %、75%肺活量时的呼气峰流速(FEF25、FEF50、FEF75)、最大呼气中期流量(MMEF75/25)分别为105%±12%、104%±12%、100%±7%、88% ±13%、90% ±14%、81% ±17%、73% ±25%、80%±17%,明显高于典型哮喘组患儿发作期肺功能各指标(PP>0.05)。不典型哮喘组激发后肺功能各指标与典型哮喘组发作期相比差异无统计学意义(P>0.05),但均低于典型哮喘组缓解期和不典型哮喘组激发前水平。结论 支气管激发试验有助于不典型哮喘患儿的诊断。     

Pulmonary function test in transfusion-dependent β-thalassemia major patients: a pilot study

Lung involvement is one of known complications of thalassemia. The aim of this study was to determine predominant type of pulmonary dysfunction and its relationship to iron overload in β-thalassemia children. Fifty thalassemia major children with treatment of regular blood transfusion and desferrioxamine participated in the study. Thirty-three boys and 17 girls (median age 12.5 years) with β-thalassemia enrolled in the study. Other information including body mass index, hematocrit, and the number of years of blood transfusion were recorded. Serum ferritin level and hematocrit were 3346 ± 1667 mg/dL and 27.7 ± 2, respectively. Pulmonary function tests were performed in all subjects for detecting pulmonary dysfunction. Thirty-five patients (70%) with thalassemia had abnormal result of spirometry. Obstructive airway disease based on reduced forced expiratory volume in 1 second (FEV(1)) and FEV(1)/forced vital capacity (FVC) ratio <80% was detected in 4 patients (8%). Six patients (12%) showed restrictive pattern, as defined by a reduction FVC <80% and FEV(1)/FVC ratio ≥80%. In this study, small airway involvement based on presence of forced expiratory flow (FEF(25%-75%)) <60%, FEV(1)/FVC ratio >70%, and FVC >80% was detected in 25 subjects (50%). Decreased values of peak expiratory flow rate (PEF) were detected in 23 (46%) and low FEV(1) in 10 (20%) subjects. There was no significant correlation between abnormal pulmonary function test and serum ferritin level in children with thalassemia. This study showed small airway disease was predominant abnormality in thalassemia patients, although additional larger studies are needed to evaluate underlying mechanisms and validate these findings.     

Influence of genetic variants on childhood lung function – The Generation R Study

Genetic variants associated with adult lung function could already exert the effects on childhood lung function. We aimed to examine the associations of adult lung function‐related genetic variants with childhood lung function and asthma, and whether these associations were modified by atopic predisposition, tobacco smoke exposure, or early growth characteristics. In a population‐based prospective cohort study among 3347 children, we selected 7 and 20 single nucleotide polymorphisms (SNPs) associated with adult forced expiratory volume in 1 second (FEV ₁) and FEV ₁/forced vital capacity (FEV ₁/FVC ), respectively. Weighted genetic risk scores (GRS s) for FEV ₁ and FEV ₁/FVC were constructed. At age 10, FEV ₁, FVC , FEV ₁/FVC , forced expiratory flow between 25% and 75% (FEF _25‐75), and forced expiratory flow at 75% (FEF ₇₅) of FVC were measured, and information on asthma was obtained by parental‐reported questionnaires. The FEV ₁‐GRS was associated with lower childhood FEV ₁, FEV ₁/FVC , and FEF ₇₅ (Z ‐score (95% CI ): ?0.03 (?0.05, ?0.01), ?0.03 (?0.05, ?0.01), and ?0.04 (?0.05, ?0.01), respectively, per additional risk allele). The FEV ₁/FVC ‐GRS was associated with lower childhood FEV ₁/FVC and FEF ₇₅ (Z ‐score (95% CI ): ?0.04 (?0.05, ?0.03) and ?0.03 (?0.05, ?0.02), respectively, per additional risk allele). Effect estimates of FEV ₁‐GRS with FEF _25‐75, FEV ₁, FEF ₇₅, and FVC , and of FEV ₁/FVC ‐GRS with FEV ₁/FVC and FEF _25‐75 were stronger among children exposed to non‐atopic mothers, smoking during pregnancy or in childhood, or those born with a lower birthweight, respectively (P ‐values for interaction < .05). Genetic risk scores were not associated with asthma. Adult lung function‐related genetic variants were associated with childhood lung function. Maternal atopy, smoking during pregnancy or in childhood, and birthweight modified the observed effects.