OBJECTIVE: To measure and compare the quantitative parameters of the lungs and airways in Korean never-smokers and current or former smokers (“ever-smokers”). MATERIALS AND METHODS: Never-smokers (n = 119) and ever-smokers (n = 45) who had normal spirometry and visually normal chest computed tomography (CT) results were retrospectively enrolled in this study. For quantitative CT analyses, the low attenuation area (LAA) of LAA(I-950), LAA(E-856), CT attenuation value at the 15th percentile, mean lung attenuation (MLA), bronchial wall thickness of inner perimeter of a 10 mm diameter airway (Pi10), total lung capacity (TLC(CT)), and functional residual capacity (FRC(CT)) were calculated based on inspiratory and expiratory CT images. To compare the results between groups according to age, sex, and smoking history, independent t test, one way ANOVA, correlation test, and simple and multiple regression analyses were performed. RESULTS: The values of attenuation parameters and volume on inspiratory and expiratory quantitative computed tomography (QCT) were significantly different between males and females (p < 0.001). The MLA and the 15th percentile value on inspiratory QCT were significantly lower in the ever-smoker group than in the never-smoker group (p < 0.05). On expiratory QCT, all lung attenuation parameters were significantly different according to the age range (p < 0.05). Pi10 in ever-smokers was significantly correlated with forced expiratory volume in 1 second/forced vital capacity (r = −0.455, p = 0.003). In simple and multivariate regression analyses, TLC(CT), FRC(CT), and age showed significant associations with lung attenuation (p < 0.05), and only TLC(CT) was significantly associated with inspiratory Pi10. CONCLUSION: In Korean subjects with normal spirometry and visually normal chest CT, there may be significant differences in QCT parameters according to sex, age, and smoking history.
Female ; Forced Expiratory Volume ; Functional Residual Capacity ; Humans ; Lung* ; Male ; Reference Values ; Respiratory Function Tests ; Retrospective Studies ; Smoke ; Smoking ; Spirometry ; Thorax ; Tomography, X-Ray Computed ; Total Lung Capacity ; Vital Capacity

OBJECTIVES: To identify adverse health effects due to air pollution derived from a cement plant in Korea. The ventilation impairment in residents around a cement plant was compared to another group through a pulmonary function test (PFT). METHODS: From June to August of 2013, both a pre and post-bronchodilator PFT was conducted on a "more exposed group (MEG)" which consisted of 318 people who lived within a 1 km radius of a cement plant and a "less exposed group (LEG)" which consisted of 129 people who lived more than 5 km away from the same plant. The largest forced expiratory volume in a one second (FEV1) reading and a functional residual capacity (FVC) reading were recorded after examining the data from all of the usable curves that were agreed upon as valid by PFT experts of committee of National Institute of Environmental Research. The global initiative for chronic obstructive lung disease (GOLD) criteria for COPD, defined the FEV1/FVC ratio < 0.7 as the obstructive type, and the FEV1/FVC ratio >== 0.7 and FVC% predicted < 80% were as the restrictive type. The FVC% predicted value was estimated using Korean equation. We compared the proportion of lung function impairments between the MEG and the LEG by using a chi-square, and estimated the OR of obstructive and restrictive ventilation impairments by logistic regression. RESULTS: The obstructive type impairment proportion was 9.7% in the MEG, whereas it was 8.5% in the LEG. The restrictive type was 21.6% in the MEG which was more than the 12.4% of the LEG. The odds ratio (OR) of total ventilation impairment in the MEG was 2.63 (95% CI 1.50 ~ 4.61) compared to the LEG. The OR of obstructive type in the MEG was 1.60 (95% CI 0.70 ~ 3.65), the smoking history was 3.10 (CI 1.10 ~ 8.66) whereas OR of restrictive type in the MEG was 2.55 (95% CI 1.37 ~ 4.76), the smoking history was 0.75 (95% CI 0.35 ~ 1.60) after adjusting for sex and age. Level of exposure to particulate played a role in both types. However, it appeared to be a significant variable in restrictive type, while smoking history was also an important variable in obstructive type. CONCLUSION: Although this study is a limited cross-section study with a small number of subjects, ventilation impairment rate is higher in the MEG. There might be a possibility that it is due to long-term exposure to particulate dust generated by the cement plant.
Air Pollution ; Dust ; Forced Expiratory Volume ; Functional Residual Capacity ; Korea ; Leg ; Logistic Models ; Lung ; Odds Ratio ; Plants* ; Pulmonary Disease, Chronic Obstructive ; Radius ; Respiratory Function Tests ; Smoke ; Smoking ; Ventilation*

OBJECTIVEBody plethysmography is a typical method to measure functional residual capacity (FRC) and airway resistance (Raw). The aim of the study was to test the feasibility of measuring lung function with the body plethysmography in young children with acute lower respiratory tract infection (ALRI) by evaluating changes and prognosis of lung function for infants with ALRI with or without wheezing via body plethysmograph.

METHODPulmonary function tests (PFTs) were performed by using body plethysmography in 444 children with ALRI, aged 1-36 months, to assess their tidal breathing parameters such as ratio of time to peak tidal expiratory flow to total expiratory time (TPTEF/TE), ratio of volume to peak tidal expiratory flow to total expiratory volume (VPTEF/VE), plethysmographic functional residual capacity (FRCP), FRCP per kilogram (FRCP/kg), specific effective airway resistance (sReff), effective airway resistance (Reff), Reff per kilogram (Reff/kg), etc. According to whether there was wheezing or not, children who had ALRI with wheezing were classified as Group-W, or without wheezing as Group-N. Changes or correlations of tidal breathing parameters and plethysmographic parameters were compared.One hundred and three contemporaneous healthy controls aged 1-36 months underwent the same tests for comparison. And 36 wheezing children accepted PFTs at follow-up in recovery phase.

RESULTMean values of TPTEF/TE in Group-W,Group-N and the Control respectively were (20.5 ± 6.7)%,(22.8 ± 6.5)%,(34.6 ± 5.0)% (F = 110.500, P < 0.001), while VPTEF/VE respectively were (23.0 ± 6.3)%,(25.2 ± 6.8)%,(34.5 ± 4.2)% (F = 107.800, P < 0.001). Compared to the Control,Group-W and Group-N had significantly higher values of FRCP (226 vs. 176 vs. 172 ml, χ(2) = 64.870, P < 0.001), FRCP/kg(24.40 vs.17.80 vs.17.60 ml/kg,χ(2) = 68.890, P < 0.001), sReff(1.00 vs. 0.52 vs. 0.46 kPa·s,χ(2) = 75.240, P < 0.001), Reff (3.90 vs.2.74 vs.2.20 kPa·s/L, χ(2) = 36.480, P < 0.001) and Reff/kg [0.42 vs. 0.29 vs.0.22 kPa·s/(L·kg), χ(2) = 29.460, P < 0.001]. Although 25 (12.8%) wheezing children with ALRI had normal values of tidal breathing parameters, they already had increased FRCP, FRCP /kg, sReff, Reff and Reff/kg (t = 2.221, 1.997, 2.502, 2.587, 2.539, all P < 0.05). Values of FRCP and Reff in infants caught ALRI were inversely correlated to that of TPTEF/TE and VPTEF/VE (P < 0.05); 36 children with wheezing who accepted PFTs at follow-up had shown significant decline in the specific parameters of plethysmography such as FRCP, FRCP/kg, sReff, Reff and Reff/kg (Z = -1.999, -2.195, -2.038, -1.823, -2.054, all P < 0.05), while no improvement in the main parameters of tidal breathing such as TPTEF/TE.

CONCLUSIONMeasuring lung function with the body plethysmography in young children with ALRI is feasible. FRC and Raw, as special lung function testing parameters of body plethysmography, were sensitive indicators reflecting impairment of lung function in infants with ALRI (especially for children caught ALRI with wheezing) and shows significant correlation with parameters from lung function testing via tidal breathing. Therefore plethysmography is worthy of clinical promotion.

Airway Resistance ; physiology ; Case-Control Studies ; Child, Preschool ; Female ; Functional Residual Capacity ; physiology ; Humans ; Infant ; Lung ; physiopathology ; Male ; Plethysmography, Whole Body ; Respiratory Function Tests ; Respiratory Sounds ; diagnosis ; physiopathology ; Respiratory Tract Diseases ; diagnosis ; physiopathology ; Tidal Volume

Pulmonary function testing (PFT) is an important and fundamental method in the evaluation and treatment of respiratory diseases. Airway responsiveness assessed using histamine or methacholine by PFT is meaningful for the diagnosis of asthma. Spirometry is simple, and has been the most commonly used technique. However, in younger or uncooperative children, other commercially available tools such as impulse oscillometry (IOS), gas dilution, and plethysmography have been used. IOS is a noninvasive method that allows the measurement of airway mechanics (resistance [R] and reactance [X]) with minimal patient cooperation. Functional residual capacity (FRC) is one of the most important measurements obtained by gas dilution. Plethysmography is a gold standard to measure airway resistance and useful for lung function testing in infants. The purpose of this review is to help pediatric physicians being familiar with PFT techniques used in young children by discussing their principles, clinical applications, limitations, and current accessibility in Korea.
Airway Resistance ; Asthma ; Child* ; Diagnosis ; Functional Residual Capacity ; Histamine ; Humans ; Infant ; Korea ; Lung* ; Mechanics ; Methacholine Chloride ; Oscillometry ; Patient Compliance ; Plethysmography ; Respiratory Function Tests ; Spirometry

BACKGROUND: The use of positive end expiratory pressure (PEEP) in patients with acute lung injury (ALI) improves arterial oxygenation by alleviating pulmonary shunting, helping the respiratory muscles to decrease the work of breathing, decreasing the rate of infiltrated and atelectatic tissues, and increasing functional residual capacity. In a rabbit model of saline lavage-induced ALI, we examined the effects of PEEP on gas exchange, hemodynamics, and oxygenation during high frequency jet ventilation (HFJV), and then compared these parameters with those during conventional mechanical ventilation (CMV). METHODS: Twelve rabbits underwent repeated saline lavage to create ALI. The animals were divided in 2 groups: 1) Group CMV (n = 6), and 2) Group HFJV (n = 6). In both groups, we applied 2 levels of PEEP (5 cmH2O and 10 cmH2O) and then measured the arterial blood gas, mixed venous blood gas, and hemodynamic parameters. RESULTS: With administration of PEEP of either 5 cmH2O or 10 cmH2O, the arterial oxygen content of both groups was increased, although without statistically significant differences between groups. On the contrary, the arterial carbon dioxide content was significantly decreased in the HFJV group, as compared with the CMV group, during the entire experiment. Furthermore, there was significant decreases in mean arterial pressures in both groups with a PEEP of 10 cmH2O. CONCLUSIONS: The application of PEEP in rabbits with ALI effectively improves oxygenation in either HFJV or CMV.
Acute Lung Injury ; Animals ; Arterial Pressure ; Carbon Dioxide ; Functional Residual Capacity ; Hemodynamics ; High-Frequency Jet Ventilation ; Humans ; Oxygen ; Positive-Pressure Respiration ; Rabbits ; Respiration, Artificial ; Respiratory Muscles ; Therapeutic Irrigation ; Work of Breathing

BACKGROUNDThe respiratory system changes with age and a better understanding of the changes contribute to detect and prevent respiratory dysfunctions in old population. The purpose of this study was to observe age-associated changes of pulmonary function parameters in healthy young adults and the elderly.

METHODSA cross-sectional study was conducted among 600 male and female subjects aged 19 to 92 years. The subjects were divided into three groups by age: young adult (19 - 39 years), middle-aged adult (40 - 59 years), and the elderly (≥ 60 years). The pulmonary function was measured with routine examination methods and 13 parameters including vital capacity (VC), residual volume (RV), functional residual capacity (FRC), total lung capacity (TLC), RV/TLC, forced vital capacity (FVC), forced expiratory volume in one second (FEV(1)), FEV(1)/FVC, peak expiratory flow (PEF), forced expiratory flow at 25% of FVC exhaled (FEF(25)), forced expiratory flow at 50% of FVC exhaled (FEF(50)), diffusion capacity of the lung for carbon monoxide (D(L)CO), and specific diffusion capacity of CO (KCO) were collected and analyzed. Changes in pulmonary function parameters among the pre-elderly and elderly subjects, especially the aging influence on FEV(1)/FVC and RV were studied further.

RESULTSTen pulmonary function parameters including VC, FVC, FEV(1), FEV(1)/FVC, PEF, FEF(25), FEF(50), TLC, D(L)CO and KCO decreased significantly with age in both male and female subjects (P < 0.01). RV and RV/TLC were increased with age (P < 0.01). FRC remained stable during aging. Except FRC, the linear relationship was significant between age and other pulmonary function parameters. In the pre-elderly and elderly subjects, RV had a non-significantly increasing tendency with age (P > 0.05), and FEV(1)/FVC did not change significantly with age (P > 0.05).

CONCLUSIONTotal pulmonary function was declined with advancing age, but FRC was stable, and the increasing tendency of RV and decreasing tendency of FEV(1)/FVC obviously slowed down in the pre-elderly and elderly subjects.

Adult ; Age Factors ; Aged ; Aged, 80 and over ; Aging ; physiology ; Cross-Sectional Studies ; Female ; Forced Expiratory Volume ; Functional Residual Capacity ; Humans ; Lung ; physiology ; Male ; Middle Aged ; Vital Capacity ; Young Adult

Neonatologists are deeply concerned with the concept of ventilator-induced lung injury (VILI) and they are greatly careful in the neonatal intensive care unit to apply positive-pressure ventilation (PPV) strategies that are gentle to the lungs. To achieve adequate gas exchange after delivery, lung fluid should be cleared and replaced with air, and functional residual capacity (FRC) should be established. However preterm newborns have difficulties establishing FRC and maintaining upper airway patency at birth. Hence majority of preterm newborns need some assistance to initiate breathing after birth and some require extensive resuscitation. PPV is therefore commonly used in the delivery room, however most clinicians including neonatologists or obstetricians appear less aware that the gentle approach as in NICU should be applied to prevent lung injury during the first few minutes of life. PPV may cause lung injury through various mechanisms such as high Vt (tidal volume) and overdistension (volutrauma), repeated alveolar collapse and re-expansion (atelect-trauma), and infection and inflammation (biotrauma), through which leads to epithelial cell injury, leakage of proteinaceous fluid into the lungs, inhibiting surfactant function and interfering lung mechanics, and consequently generating lung injury. In this review, I describe briefly what causes preterm lung injury during PPV based on animal and human researches, and I suggest some strategies to help minimize lung injury during resuscitation of preterm newborns in the delivery room.
Animals ; Delivery Rooms ; Epithelial Cells ; Functional Residual Capacity ; Humans ; Infant, Newborn ; Inflammation ; Intensive Care, Neonatal ; Lung ; Lung Injury ; Mechanics ; Parturition ; Positive-Pressure Respiration ; Respiration ; Resuscitation ; Ventilator-Induced Lung Injury

PURPOSE: Pulmonary function is decreased in varying degrees in healthy premature infants as well as those with bronchopulmonary dysplasia. The evaluation of pulmonary function in infants is finally standardized after strenuous efforts, but it has not yet been in Korea. In this study, we aimed at the evaluation of the utility of pulmonary function tests in premature infants with chronic lung disease by objectively measuring pulmonary function and by analyzing the risk factors that may decrease lung function. METHODS: Fifty-four premature infants born in Severance Hospital were selected. Among the 54 infants, 31 were male and 23 were female, and their mean age was 5.6+/-3.7 years. Exhalyser was used to measure tidal volume and functional residual capacity, and then their change after the inhalation of bronchodilators was evaluated. There was no test related complication in all subjects. RESULTS: Among the 54 subjects, 22 were at the gestational age of <28 weeks, 25 were at the gestational age between 28 and 33 weeks, and 7 were at the gestational age between 33 and 37 weeks. As for birth weight, 23 had extreme low birth weight, 23 had very low birth weight, and 8 had low birth weight. The delta functional residual capacities (FRCs) before and after the inhalation of bronchodilator were significantly increased in infants with younger gestational age (P<0.05) and lower birth weight (P<0.05). There was a significant negative correlation between gestational age and birth weight, and a significant positive correlation with the duration of ventilator care and that of oxygen therapy. The delta FRC before the inhalation of bronchodilator was significantly lower in infants with lower birth weight, and the tidal volume before the inhalation of bronchodilator correlated negatively with the duration of ventilator care. CONCLUSION: The reversibility of FRC is increased in premature infants with lower birth weight, younger gestational age, and longer duration of ventilator care and oxygen therapy. The reversibility of FRC may be a useful parameter of pulmonary function that can be safely measured in premature infants with chronic lung disease.
Birth Weight ; Bronchodilator Agents ; Bronchopulmonary Dysplasia ; Female ; Functional Residual Capacity ; Gestational Age ; Humans ; Infant ; Infant, Low Birth Weight ; Infant, Newborn ; Infant, Premature ; Infant, Very Low Birth Weight ; Inhalation ; Korea ; Lung ; Lung Diseases ; Male ; Oxygen ; Respiratory Function Tests ; Risk Factors ; Tidal Volume ; Ventilators, Mechanical

Atelectasis can impair arterial oxygenation and decrease lung compliance. However, the effects of atelectasis on endotoxemic lungs during ventilation have not been well studied. We hypothesized that ventilation at low volumes below functional residual capacity (FRC) would accentuate lung injury in lipopolysaccharide (LPS)-pretreated rats. LPS-pretreated rats were ventilated with room air at 85 breaths/min for 2 hr at a tidal volume of 10 mL/kg with or without thoracotomy. Positive end-expiratory pressure (PEEP) was applied to restore FRC in the thoracotomy group. While LPS or thoracotomy alone did not cause significant injury, the combination of endotoxemia and thoracotomy caused significant hypoxemia and hypercapnia. The injury was observed along with a marked accumulation of inflammatory cells in the interstitium of the lungs, predominantly comprising neutrophils and mononuclear cells. Immunohistochemistry showed increased inducible nitric oxide synthase (iNOS) expression in mononuclear cells accumulated in the interstitium in the injury group. Pretreatment with PEEP or an iNOS inhibitor (1400 W) attenuated hypoxemia, hypercapnia, and the accumulation of inflammatory cells in the lung. In conclusion, the data suggest that atelectasis induced by thoracotomy causes lung injury during mechanical ventilation in endotoxemic rats through iNOS expression.
Animals ; Blood Pressure ; Carbon Dioxide/blood ; Cardiac Output ; Combined Modality Therapy ; Endotoxemia/*complications/immunology/pathology ; Functional Residual Capacity ; Immunohistochemistry ; Leukocytes, Mononuclear/pathology ; Lipopolysaccharides/pharmacology ; Lung/enzymology/pathology/physiopathology ; Lung Compliance ; Lung Volume Measurements ; Male ; Neutrophils/pathology ; Nitric Oxide Synthase Type II/metabolism ; Oxygen/blood ; Positive-Pressure Respiration/*adverse effects ; Pulmonary Atelectasis/*etiology/pathology/*therapy ; Rats ; Rats, Sprague-Dawley ; Thoracotomy/*adverse effects

OBJECTIVETo study the development of pulmonary function of healthy children between 1-48 months.

METHODSA total of 295 healthy children at ages of 1-48 months were classified into 7 groups according to their age, i.e., 1-2 months, 3-4 months, 5-7 months, 8-12 months, 13-24 months, 25-36 months, and 37- 48 months. Pediatric pulmonary function laboratory type 2600 (Sensor Medics Corporation USA) was used to detect tidal flow volume curve, which can partially replace the maximum expiratory flow volume curve and reflect airway ventilation function. Passive expiratory flow volume technique was used to examine respiratory system static compliance and total airway resistance. Open nitrogen washout method was used to measure functional residual capacity.

RESULTSThe values of tidal, peak tidal expiratory flow, and respiratory system static compliance functional residual capacity increased with the increasing age and were significantly different among the 7 groups. However, respiratory rate and total airway resistance decreased with the increased age. The value of each parameter of tidal flow volume curve was stable during 1-48 months.

CONCLUSIONSThis study displayed the developmental characteristics of pulmonary function of healthy children at ages of 1-48 months, which is useful to observe the changes of pulmonary function in respiratory diseases.

Age Factors ; Child, Preschool ; Female ; Functional Residual Capacity ; Humans ; Infant ; Lung ; physiology ; Male ; Peak Expiratory Flow Rate