Lung Function In Healthy Adults Research Articles

Retraction Note: The Effect of Preterm Birth on Maximal Aerobic Exercise Capacity and Lung Function in Healthy Adults: A Systematic Review and Meta-analysis.

Retraction Note: The Effect of Preterm Birth on Maximal Aerobic Exercise Capacity and Lung Function in Healthy Adults: A Systematic Review and Meta-analysis.

Comment on “The Effect of Preterm Birth on Maximal Aerobic Exercise Capacity and Lung Function in Healthy Adults: A Systematic Review and Meta-Analysis”

Comment on “The Effect of Preterm Birth on Maximal Aerobic Exercise Capacity and Lung Function in Healthy Adults: A Systematic Review and Meta-Analysis”

Short-term effects of the toxic component of traffic-related air pollution (TRAP) on lung function in healthy adults using a powered air purifying respirator (PAPR)

Short-term exposure to traffic-related air pollution (TRAP) are associated with reduced lung function. However, TRAP is a mixture of various gaseous pollutants and particulate matter (PM), and therefore it is unknown that which components of TRAP are responsible for the respiratory toxicity. Using a powered air-purifying respirator (PAPR), we conducted a randomized, double-blind, crossover trial in which 40 adults were exposed to TRAP for 2 h at the sidewalk of a busy road. During the exposure, the participants wore the PAPR fitted with a PM filter, a PM and volatile organic compounds (VOCs) filter, or a sham filter (no filtration, Sham mode). The participants were blinded to the type of filter in their PAPR, and experienced three exposures, once for each intervention mode in random order. We measured two lung function measures (forced expiratory volume in 1 s [FEV1] and forced vital capacity [FVC]) and an airway inflammation marker (fraction of exhaled nitric oxide [FENO]) before and immediately after each exposure, and further measured them at different time periods after exposure. We applied linear mixed effect models to estimate the effects of the interventions on the changes of lung function from baseline values after controlling for other covariates. Compared to baseline, exposing to TRAP decreased FEV1 and FVC, and increased FEV1/FVC and FENO in all three intervention modes. The mixed models showed that with the sham mode as reference, lung function and airway inflammation post exposure were significantly improved by filtering both PM and VOCs, but marginally affected by filtering only PM. In conclusion, the VOCs component of TRAP is responsible for the reduction in lung function caused by short-term exposure to TRAP. However, the result needs to be interpreted cautiously before further verified by laboratory experiment using purely isolated component(s) of TRAP.

The Effects of Fruit-Derived Polyphenols on Cognition and Lung Function in Healthy Adults: A Systematic Review and Meta-Analysis

Polyphenols are plant derived nutrients that influence oxidative stress and inflammation and therefore may have positive benefits on cognition and lung function. This systematic review and meta-analysis aimed to evaluate the effects of fruit derived polyphenol intakes on cognition and lung capacity in healthy adults. In August 2020 and October 2021, Medline and Google Scholar were used to search for relevant studies examining the effects of fruit derived polyphenol intakes on cognition and/or lung function in healthy adults (<70 years old). Fourteen studies related to cognition (409 healthy subjects) and seven lung/respiratory studies (20,788 subjects) were used for the systematic review using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. The meta-analysis (using six cognition and three lung function studies) indicated a protective effect on lung function from dietary intakes of fruit-derived polyphenols. Neither a benefit nor decrement from fruit-derived polyphenol intakes were detected for cognition. Human intervention trials examining the effects of polyphenol supplementation on lung function in healthy adults are scarce and intervention studies are warranted. More conclusive results are needed to provide recommendations for polyphenol supplementation to support aspects of cognition.

Relationships between lung function decline and skeletal muscle and fat mass changes: a longitudinal study in healthy individuals.

BackgroundThe associations between long‐term changes in body mass composition and decline in lung function in healthy adults are unknown.MethodsUsing a well‐defined health check‐up database, we first assessed individual longitudinal changes in muscle mass (MM) and fat mass (FM) measured via bioelectrical impedance analyses. Then we classified the enrolled individuals into five body composition groups according to their MM index (MMI) [MM (kg)/height (m)2] or FM index (FMI) [FM (kg)/height (m)2] change rate quartiles. Linear mixed models adjusted for age, smoking status, height, and body mass index were used to analyse the rate of forced expiratory volume in 1 s (FEV1) decline and body composition groups.ResultsA total of 15 476 middle‐aged individuals (6088 women [mean age ± standard deviation: 50.74 ± 7.44] and 9388 men [mean age ± standard deviation: 49.36 ± 6.99]) were enrolled. The mean number of measurements was 6.96 (interquartile range [IQR]: 5–9) over an average follow‐up period of 8.95 years (IQR: 6.73–11.10). Decrease in MMI was significantly associated with accelerated FEV1 decline in men only (P = 1.7 × 10−9), while increase in FMI was significantly associated with accelerated FEV1 decline in both women and men (P = 7.9 × 10−10 and P < 2.0 × 10−16 respectively). Linear mixed model analyses indicated that annual increase of 0.1 kg/m2 in MMI was related to accelerated FEV1 decline by 30.79 mL/year (95% confidence interval [CI]: 26.10 to 35.48 mL/year) in men. Annual increase of 0.1 kg/m2 in FMI was related to accelerated FEV1 decline by 59.65 mL/year in men (95% CI: 56.84 to 62.28 mL/year) and by 22.84 mL/year in women (95% CI: 18.95 to 26.74 mL/year). In body composition analysis, we found increase in MMI was significantly associated with attenuated FEV1 decline in men only (P = 1.7 × 10−9), while increase in FMI was significantly associated with accelerated FEV1 decline in both women and men (P = 7.9 × 10−10 and P < 2.0 × 10−16 respectively). Individuals characterized with gain MM combined with loss of FM were associated with the most favourable outcome (i.e. the smallest rate of decline in FEV1) in both women and men. In men, loss of FM over time is more closely related with attenuated FEV1 decline than change in MM (gain or loss).ConclusionsChange in body composition over time can be used to identify healthy middle‐aged individuals at high risk for rapid FEV1 decline.

Short-term personal and outdoor exposure to ultrafine and fine particulate air pollution in association with blood pressure and lung function in healthy adults

Studies reporting on associations between short-term exposure to outdoor fine (PM2.5), and ultrafine particles (UFP) and blood pressure and lung function have been inconsistent. Few studies have characterized exposure by personal monitoring, which especially for UFP may have resulted in substantial exposure measurement error. We investigated the association between 24-h average personal UFP, PM2.5, and soot exposure and dose and the health parameters blood pressure and lung function. We further assessed the short-term associations between outdoor concentrations measured at a central monitoring site and near the residences and these health outcomes.We performed three 24-h personal exposure measurements for UFP, PM2.5, and soot in 132 healthy adults from Basel (Switzerland), Amsterdam and Utrecht (the Netherlands), and Turin (Italy). Monitoring of each subject was conducted in different seasons in a one-year study period. Subject's activity levels and associated ventilation rates were measured using actigraphy to calculate the inhaled dose. After each 24-h monitoring session, blood pressure and lung function were measured. Contemporaneously with personal measurements, UFP, PM2.5 and soot were measured outdoor at the subject's residential address and at a central site in the research area. Associations between short-term personal and outdoor exposure and dose to UFP, PM2.5, and soot and health outcomes were tested using linear mixed effect models.The 24-h mean personal, residential and central site outdoor UFP exposures were not associated with blood pressure or lung function. UFP mean exposures in the 2-h prior to the health test was also not associated with blood pressure and lung function. Personal, central site and residential PM2.5 exposure were positively associated with systolic blood pressure (about 1.4 mmHg increase per Interquartile range). Personal soot exposure and dose were positively associated with diastolic blood pressure (1.2 and 0.9 mmHg increase per Interquartile range). No consistent associations between PM2.5 or soot exposure and lung function were observed.Short-term personal, residential outdoor or central site exposure to UFP was not associated with blood pressure or lung function. Short-term personal PM2.5 and soot exposures were associated with blood pressure, but not lung function.

The relationship between heart rate inflection point and lactate recovery and lung function in healthy adults at the Plateau

Objective: To explore the relationship between heart rate deflection point (HRDP) and blood lactate recovery ability and lung function of healthy people aged 20～40 years old in a plateau environment of 3 200 m. Methods: 225 healthy people aged 20～40 who lived on a plateau of 3 200 m were used as the research subjects. The HRDP strength, heart rate recovery ability and blood lactate recovery ability were evaluated by the changes of heart rate and blood lactate recovery before, during and after the modified Conconi test. Results: ①The heart rate of the subjects increased with the increase in exercise intensity, and the heart rate of the recovery period after exercise showed a downward trend, the rate of Conconi test center was significantly lower in male than that in female(P＜ 0.05). At the same age, male HRDP appeared later, and female HRDP appeared earlier. At the same sex stage, the time of HRDP appeared earlier in the male group with increasing age, while the phenomenon in the female group was not significant. HRDP speed had a downward trend with age. ②The inflection point concentration of blood lactic acid in the subjects gradually decreased with age, but there was no significant difference between the low-age group and the high-age group; the blood lactic acid level in the Conconi test of healthy adult males living on the plateau was significantly lower than that of females(P＜0.05). ③FVC, MVV, FEV1 and FEV1/FVC levels in each gender group showed a downward trend with age, and the data of the male group and above were significantly higher than the female group of the same age (P＜0.05). ④Load-Heart Rate curve and Heart Rate-Blood Lactate fitting curve showed that the correlation coefficients of the male group were 0.8345, 0.8954, 0.8680, and 0.8892 in sequence; the correlation coefficients of the female group were in sequence 0.9318, 0.9661, 0.9663 and 0.9599. HRDP values of all genders and age groups were significantly correlated with their MVV levels (P＜0.05). Except for subjects 36～40 years old in the male group, lung function and lactate elimination rate of all genders and age groups were also significantly correlated (P＜0.05). Conclusion: There are age and gender differences in exercise heart rate response rules and respiratory system functions of healthy people aged 20～40 years old living on 3 200 m plateau. There is a significant correlation between HRDP and lactic acid recovery capacity and lung function. The above indicators can be used to assess the aerobic exercise endurance ability of healthy adults living on plateau.

The Association of Dietary Macronutrients with Lung Function in Healthy Adults Using the Ansan-Ansung Cohort Study.

This study is aimed to examine the association between macronutrient intake and lung function in healthy adults (n = 5880) using the Ansan-Ansung cohort study. To identify the index of lung function, we used the percentage difference of predicted Forced Expiratory Volume (%FEV1_diff) between baseline and follow-up. Based on the median %FEV1_diff, subjects were classified by two groups as “decreased vs. unchanged/improved”. The dietary macronutrients were estimated and validated using the food-frequency questionnaire. Multiple logistic regression models were used to evaluate the association after adjusting for confounders. Advanced analysis examined the association after stratifying by age and obesity. The average of %FEV1 is 114.1 and 112.5 at baseline and follow-up, respectively. The positive association of protein and fiber intake with lung function was observed in men. Low fat and high carbohydrate intake decreased the lung function in women only. After stratification by age, the association of protein, fat, and carbohydrate intake with lung function was observed in young men and old women only. Otherwise, the association of protein and fiber with lung function was influenced by abdominal obesity. In conclusion, the lung function was positively associated with high protein and fat intake, but was negatively associated with high carbohydrate intake, which could be influenced by age and obesity.

Effects of Particulate Air Pollution on Lung Function in Healthy Adults and Adults With Asthma: A Systematic Review and Meta-Analysis

Effects of Particulate Air Pollution on Lung Function in Healthy Adults and Adults With Asthma: A Systematic Review and Meta-Analysis

Short-term air pollution exposure decreases lung function: a repeated measures study in healthy adults

BackgroundDaily changes in ambient concentrations of particulate matter, nitrogen oxides and ozone are associated with increased cardiopulmonary morbidity and mortality, with the lungs and their function being a vulnerable target.MethodsTo evaluate the association between daily changes in air pollution and lung function in healthy adults we obtained annual lung function measurements from a routine worker health surveillance program not designed for research purposes. Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1), FEV1/FVC and Peak Expiratory flow (PEF) from a cohort of 2449 employees were associated with daily measurements of PM10, NO2 and ozone at a nearby monitoring station in the North of Belgium. Repeated measures were available for the period 2011–2015.ResultsThe mean (SD) PM10 concentration on the day of the lung function test was 24.9 (15.5) μg/m3. A 10 μg PM10/m3 increase on the day of the clinical examination was associated with a 18.9 ml lower FVC (95% CI: -27.5 to −10.3, p < 0.0001), 12.8 ml lower FEV1 (−19.1 to −6.5; p < 0.0001), and a 51.4 ml/s lower PEF (−75.0 to −27.0; p < 0.0001). The FEV1/FVC-ratio showed no associations. An increase of 10 μgNO2/m3 was associated with a reduction in PEF (−66.1 ml/s (−106.6 to −25.6; p < 0.001)) on the day of the examination.ConclusionsWe found negative associations between daily variations in ambient air pollution and FVC, FEV1 and PEF in healthy adults.

Systemic inflammation and lung function: A longitudinal analysis

BackgroundSystemic inflammation is associated with impaired lung function in healthy adults as well as in patients with lung disease. The mechanism for this association is unknown and it is unclear if systemic inflammation leads to impaired lung function or if poor lung function leads to inflammation. We explored the temporal associations between blood C-reactive protein (CRP), fibrinogen, and white blood cells, and lung function in young adults. MethodsSpirometry, plethysmography, and diffusion capacity were measured in a population-based cohort at ages 32 and 38 years. High-sensitivity CRP, fibrinogen, and white blood cells were measured at the same ages. ResultsHigher levels of CRP and, to a lesser extent, fibrinogen were associated with lower lung volumes in cross-sectional analyses at both ages 32 and 38 years. Higher CRP and fibrinogen at age 32 were associated with higher FEV1 and FEV1/FVC at age 38, but not other measures of lung function. Lower lung volumes (total lung capacity, functional residual capacity, and residual volume) but not airflow obstruction (FEV1/FVC) at age 32 were associated with higher CRP at age 38. Associations between age 32 lung function and fibrinogen at follow-up were weaker, but consistent. There were no longitudinal associations between white blood cells and lung function. ConclusionsWe found no evidence that systemic inflammation causes a decline in lung function. However, lower lung volumes were associated with higher CRP and fibrinogen at follow-up indicating that pulmonary restriction may be a risk factor for systemic inflammation. The mechanism for this association remains unclear.

Respiratory effects of fine and ultrafine particles from indoor sources--a randomized sham-controlled exposure study of healthy volunteers.

Particulate air pollution is linked to impaired respiratory health. We analyzed particle emissions from common indoor sources (candles burning (CB), toasting bread (TB), frying sausages (FS)) and lung function in 55 healthy volunteers (mean age 33.0 years) in a randomized cross-over controlled exposure study. Lung-deposited particle surface area concentration (PSC), size-specific particle number concentration (PNC) up to 10 µm, and particle mass concentration (PMC) of PM1, PM2.5 and PM10 were determined during exposure (2 h). FEV1, FVC and MEF25%–75% was measured before, 4 h and 24 h after exposure. Wilcoxon-rank sum tests (comparing exposure scenarios) and mixed linear regression using particle concentrations and adjusting for personal characteristics, travel time and transportation means before exposure sessions were performed. While no effect was seen comparing the exposure scenarios and in the unadjusted model, inverse associations were found for PMC from CB and FS in relation to FEV1 and MEF25%–75%. with a change in 10 µg/m3 in PM2.5 from CB being associated with a change in FEV1 of −19 mL (95%-confidence interval:−43; 5) after 4 h. PMC from TB and PNC of UFP were not associated with lung function changes, but PSC from CB was. Elevated indoor fine particles from certain sources may be associated with small decreases in lung function in healthy adults.

Indoor molds and lung function in healthy adults

Indoor mold exposure is common worldwide and constitutes an important health problem. There are very few studies assessing the relation between mold exposure and lung function levels among non-asthmatic adults. Our objective was to assess the relations between dampness and mold exposures at home and at work and lung function. In particular, we elaborated the importance of different exposure indicators. In a population-based study, 269 non-asthmatic adults from South Finland answered a questionnaire on indoor dampness and mold exposures at home or at work and other factors potentially influencing lung function, and performed spirometry. Multiple linear regression model was applied to study the relations between exposures and spirometric lung function levels. In linear regression adjusting for confounding, FEV1 level was reduced on average 200ml related to mold odor at home (effect estimate -0.20, 95% CI -0.60 to 0.21) and FVC level was reduced on average 460ml (-0.46, -0.95 to 0.03) respectively. Exposure to mold odor at home or at work or both was related to reduced FEV1 (-0.15, -0.42 to 0.12) and FVC (-0.22, -0.55 to 0.11) levels. Women had on average 510ml reduced FEV1 levels (-0.51, -1.0 to 0.03) and 820ml reduced FVC levels (-0.82, -1.4 to -0.20) related to mold odor exposure at home. Mold odor exposure was related to lower lung function levels among non-asthmatic adults, especially among women.

Fine particulate matter, temperature, and lung function in healthy adults: Findings from the HVNR study

Both ambient particulate air pollution and temperature alterations have been associated with adverse human health effects, but the interactive effect of ambient particulate and temperature on human health remains uncertain. The present study investigated the effects of ambient particulate matter with an aerodynamic diameter⩽2.5μm (PM2.5) and temperature on human lung function simultaneously in a panel of 21 healthy university students from the Healthy Volunteer Natural Relocation (HVNR) study in the context of suburban/urban air pollution in Beijing, China. Each study subject used an electronic diary meter to record peak expiratory flow (PEF) and forced expiratory volume in 1s (FEV1) twice a day for 6months in three periods before and after relocating from a suburban area to an urban area with changing ambient PM2.5 and temperature levels in Beijing. Hourly-averaged environmental data were obtained from central air-monitoring sites. Exposure effects were estimated using generalized linear mixed models controlling for potential confounders. Study subjects provided 6494 daily measurements on PEF and 6460 daily measurements on FEV1 over the study. PM2.5 was associated with reductions in evening PEF and morning/evening FEV1 whereas temperature was associated with reductions in morning PEF. The estimated PM2.5 effects on evening PEF and morning/evening FEV1 in the presence of high temperature were generally stronger than those in the presence of low temperature, and the estimated temperature effects on morning/evening PEF and morning FEV1 in the presence of high PM2.5 were also generally stronger than those in the presence of low PM2.5. For example, there were a 2.47% (95% confidence interval: −4.24, −0.69) reduction and a 0.78% (95% confidence interval: −1.59, 0.03) reduction in evening PEF associated with an interquartile range increase (78.7μg/m3) in PM2.5 at 4-d moving average in the presence of high temperature (⩾21.6°C) and low temperature (<21.6°C), respectively. Our findings suggest that ambient particulate and temperature may interact synergistically to cause adverse respiratory health effects.

Adiponectin in Pulmonary Disease and Critically Ill Patients

Adiponectin is a predominantly anti-inflammatory protein produced by adipose tissue with possible signalling activity in the lung. It is increasingly associated with inflammatory pulmonary diseases, such as asthma and chronic obstructive pulmonary disease (COPD), and in critical illness. Although mouse studies indicate causative associations between adiponectin and asthma and COPD, the human literature in this regard is inconclusive. Some, but not all, studies demonstrate that serum adiponectin concentrations are inversely associated with asthma prevalence among premenopausal women and peripubertal girls. On the other hand, serum adiponectin concentrations are associated with lower asthma severity among boys but greater severity among men. Further, case-control studies demonstrate higher systemic and airway adiponectin concentrations in primarily male COPD patients than controls. Systemic adiponectin is positively associated with lung function in healthy adults but inversely associated in studies of male subjects with COPD. Murine and human studies further show contradictory associations of systemic adiponectin with critical illness. Higher premorbid systemic adiponectin concentrations are associated with improved survival from sepsis in mice. On the other hand, higher systemic adiponectin concentrations on day 1 of critical illness are associated with lower survival in critically ill patients with respiratory failure. In the absence of adequate longitudinal data, it is not possible to determine whether the adiponectin derangements are the consequence or the cause of the disease studied. Future research will determine whether modulation of adiponectin, independent of BMI, may be helpful in the prevention or treatment of asthma, COPD or critical illness.

Leptin, adiponectin and pulmonary diseases

Adipose tissue produces leptin and adiponectin - energy-regulating adipokines that may also play a role in inflammatory pulmonary conditions, as suggested by some murine studies. Leptin and adiponectin and their respective receptors are expressed in the human lung. The association between systemic or airway leptin and asthma in humans is currently controversial, particularly among adults. The majority of the evidence among children however suggests that systemic leptin may be associated with greater asthma prevalence and severity, particularly among prepubertal boys and peripubertal/postpubertal girls. Systemic and airway leptin concentrations may also be disproportionately higher in chronic obstructive pulmonary disease (COPD) patients, particularly among women, and reflect greater airway inflammation and disease severity. Quite like leptin, the association between systemic and airway adiponectin and asthma in humans is also controversial. Some but not all studies, demonstrate that serum adiponectin concentrations are protective against asthma among premenopausal women and peripubertal girls. On the other hand, serum adiponectin concentrations are inversely associated with asthma severity among boys but positively associated among men. Further, systemic and airway adiponectin concentrations are higher in COPD patients than controls, as demonstrated by case-control studies of men. Systemic adiponectin is also positively associated with lung function in healthy adults but inversely associated with lung function in subjects with COPD. It is therefore possible that pro-inflammatory effects of adiponectin dominate under certain physiologic conditions and anti-inflammatory effects under others. The adipokine-lung disease literature has critical gaps that include a lack of adequately powered longitudinal or weight-intervention studies; inadequate adjustment for confounding effect of obesity; and unclear understanding of potential sex interactions. It is also uncertain whether adipokine derangements precede pulmonary disease or are a consequence of it. Future research will determine whether modulation of adipokines, independent of BMI, may allow novel ways to prevent or treat inflammatory pulmonary conditions.

Serum vitamin D levels and exercise-induced bronchoconstriction in children with asthma

Epidemiological studies have established a relationship between low levels of serum vitamin D and reduced lung function in healthy adults, and asthma onset and severity in children. However, no study has examined the relationship between vitamin D levels and exercise-induced bronchoconstriction in asthmatic children. We evaluated the relationship between 25-hydroxyvitamin D concentrations and baseline forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and change in FEV1 (ΔFEV1) after a standardised exercise challenge in 45 children with intermittent asthma. Only 11% of the children had desirable serum vitamin D levels (at least 30-40 ng·mL(-1)). A positive correlation was found between serum 25-hydroxyvitamin D and both FVC (r=0.34; p=0.037) and FEV1 (r=0.32; p=0.037). Subjects with a positive response to the exercise challenge (ΔFEV1≥10%) presented lower serum levels of 25-hydroxyvitamin D than children with a negative challenge (mean±sd 16.2±5.2 versus 23.4±7.0 ng·mL(-1), respectively; p=0.001). Our results indicate that hypovitaminosis D is frequent in asthmatic children who live in a Mediterranean country. In those children, lower levels of vitamin D are associated with reduced lung function and increased reactivity to exercise.

Effects of aging on lung function. A comparison of lung function in healthy adults and the elderly

IntroductionThe respiratory system changes with age and understanding these changes helps detect and prevent respiratory dysfunctions in the elderly. AimsThis study compares the respiratory pattern in healthy non-smoker adults and the elderly, using lung function testing and expansion of the chest to confirm the effects of aging on lung function. MethodologyWe used lung function testing to measure forced vital capacity, forced expiratory volume in one second, peak expiratory flow rate and maximum voluntary ventilation. We also measured expansion of the chest. Measurements were taken with subjects resting in the dorsal recumbent position with upper body elevated to 45°. Statistical analysis consisted of the Student T test for independent samples, the non-parametric Mann-Whitney test with a p<0.05 level, and linear regression analysis, also with a p<0.05 level, to assess correlation between variables studied and age.Our population consisted of 35 elderly subjects and 35 adults. 15 of the elderly subjects were male (43%) and 20 female (57%). 16 of the adult group were male (46%) and 19 female (54%). The sample was mapped in terms of age, weight, height, abdominal girth and clinical data, to exclude factors which could distort the results. ResultsThe difference between the two study groups attained statistical significance for all parameters measured. The linear relationship was also significant between age and all parameters and a negative and significant correlation was seen. Expansion of the chest in females was the parameter most inversely correlated with age (60.37%). The lung function testing variable with the greatest difference between the groups was peak expiratory flow rate (35.77% in females and 36.17% in males). ConclusionsOur results show differences in the respiratory patterns of healthy adults and the elderly, suggesting that age impacts on lung function. Both male and female elderly subjects had lower lung function testing scores than the adult subjects, with this difference more marked in females.

The effect of lower limb passive movement on lung function

This study examined the effects of ankle passive movement on lung function in healthy adults. A pre-test post-test experimental design was used. Passive plantar and dorsiflexion of the ankle were performed at 60 repetitions per minute on 60 healthy subjects in the supine position. Lung function at rest was compared to that during passive movements. The results indicated that all measured parameters including the breathing frequency, tidal volume, minute ventilation, oxygen consumption and carbon dioxide output, increased significantly during passive movements as compared to those at rest. The authors conclude that passive movements elicit a significant ventilatory increase in healthy human subjects. The effect of passive movements in the treatment of unconscious or diseased individuals should be investigated.

Fat Emulsions and Lung Function

IVFE infusion can impair lung function in healthy adults, premature infants, and adults with pre-existing lung injury, and in experimental animals with acute injury. Although all observed IVFE-related lung dysfunction was initially attributed to the temporally associated hyperlipemia, this explanation may in fact be correct only with fat overload syndrome. When serum triglyceride levels are in a more appropriate range, all subsequent studies have shown the same alterations in lung function unrelated to triglyceride increases and indomethacin-related blocking of lung function impairment, despite comparable serum triglyceride increases. Furthermore, our studies with Liposyn demonstrated the most significant increases in serum triglyceride levels, but the smallest PaCO2 and PaO2 changes. In general, the lung function abnormalities associated with IVFE infusion have thus been caused by increases in VA/Q inequalities. Although elucidation of the relationship between IVFE-related increased PG production and secondary VA/Q changes may be of significant physiologic import, the PaO2 and PaCO2 changes even with pre-existing lung injury have generally not been of sufficient magnitude to be of much clinical significance. The IVFE-related increases in plasma PG concentrations may, however, still have significant nonpulmonary clinical effects related to known or postulated consequences of increased plasma PG concentrations, including effects on ductus arteriosus patency, retinal and cerebral blood flow, and immune competence.