Factors Affecting Lung Capacity - Statistics Project Example

Factors Affecting Lung Capa Factors Affecting Lung Capa This research is part of the project ‘Factors affecting lung capacity in terms of age, height, and physical condition’, which used a spirometry test to make conclusions of this study. A spirometry test is a diagnostic procedure used to evaluate respiratory volumes by using a spirometer. The test usually takes to perspective airflow and lung volume measurements that can be used to differentiate obstructive from restrictive pulmonary disorders, characterize their severity, and measure responses to therapy. Measurements commonly placed as percentages are typically reported as absolute flows as well as volumes and are used to predict values using data derived from large populations of people presumed to have normal lung function. Variables used to predict normal values include age, sex, ethnicity, and height. The experiment take to account four pulmonary volumes, which are tidal volume, inspiratory reserve volume, expiratory reserve volume, and residual volume, that further on inspection provide data on nine spirometric measures. Forced Vital Capacity (FVC), Forced Expiratory Volume in 1st second (FEV1), Inspiratory Vital Capacity (IVC), Expiratory Vital Capacity (EVC), Peak Expiratory Flow (PEF), Peak Inspiratory Flow (PIF), Expiratory Reserve Volume (ERV), Inspiratory Reserve Volume (IRV), Maximum Voluntary Ventilation (MVV) (Neder, et al, 1999). Note: Statistical analysis was performed using SPSS statistical software (version 15.0). Results of descriptive statistic were expressed as mean (X), minimal (Mini) and maximal (Maxi) values, as well and standard deviation (SD).  Appropriate Hypotheses The four main parameters of a Spirometry test usually suggests that the volume of air that enters or leaves the lungs during one breathing cycle is called the tidal volume (TV). Normally, the amount of air that is expired during a breathing cycle is equal to the amount of air that is inspired during the cycle. Resting tidal volume is the amount exchanged during normal, resting breathing. According to Levitzky (2007), “during normal, quiet breathing the TV of a 70-kg adult is about 500 mL per breath, however this volume can increase dramatically, for instance, during exercise”. the hypothesis behind this is that TC can be increased when the body uses some of the inspiratory or expiratory reserve lung volume to bring more fresh air into the body. The volume of gas that is inhaled into the lungs during a maximal forced inspiration starting at the end of a normal tidal inspiration is called the inspiratory reserve volume (IRV). It is determined by the strength of contraction of the inspiratory muscles, inward elastic recoil of the lung and the chest wall. After a normal expiration, it is possible to forcibly exhale additional air from the lungs. This is called the expiratory reserve volume (ERV). The air that cannot be exhaled from the lungs is called the residual volume (RV) and averages 1200 mL. RV is important because it prevents the lungs from collapsing at very low lung volumes. The inspiratory capacity is the amount of air that can be moved into the lungs during a maximal inspiratory effort starting after a normal expiration. The inspiratory capacity is the sum of the inspiratory reserve volume and resting tidal volume. Functional residual capacity is the amount of air that remains in the lungs after a normal, resting exhalation. It is a combination of expiratory reserve volume and residual volume. The maximum amount of air that can be exhaled after a maximal inspiration is called vital capacity (VC). It includes the tidal volume, inspiratory reserve volume and expiratory reserve volume varies with gender, height and age. Vital capacity can be predicted based on these factors as follows: For males: VC = 0.052H – 0.022A – 3.60 For females: VC = 0.041H – 0.018A – 2.69 Where: VC = vital capacity H = height in centimeters A = age in years In most cases short term exercise will not change vital capacity however, long term exercise where the body becomes accustomed to increased airflow and rate of breathing over time can increase the vital capacity. Vital capacity is a reliable diagnostic indicator of pulmonary function. A person’s vital capacity should be at least 80% of the predicted value based on sex and height. Healthy individuals who exercise regularly will usually have vital capacities that are greater than predicted values. Restrictive lung diseases cause measured VC to be consistently lower than predicted values. The forced vital capacity (FVC) measures the vital capacity as the subject exhales forcefully and rapidly. Forced expiratory volume at 1 second (FEV1) is the portion of the vital capacity that is exhaled during the first second. The FEV1/FVC ratio is an important indicator of lung and airway health. Healthy individuals can expire 75-85% of their FVC in the first second. This pulmonary function test can help the clinician distinguish between obstructive and restrictive pulmonary diseases. Data Collection In order to perform the experiment a sample of 53 respondents 33 male and 20 female took part in the practice. The experimental design which would be employed was represented on a Solomon four-group designs, with groups designated as smokers and not sportsmen 20 entries, non-smokers sportsmen 15 entries, and non-smokers and not sportsmen 18 entries. All the 53 participants who took part in the experiment aged between 35-80 years, and their heights were between 155-185 centimetres. The smokers entities who smoked more than 10 cigarettes daily for longer than one year were chosen, the non-smokers entities were chosen randomly, whereas the sportsmen entities were soccer players. A computer-simulator pulmonary function analyzer QUARKPFT, with hardware and software with requirements in agreement with American Thoracic Society and European Respiratory Society approvals, performed the spirometric measures in the test. Statistical Analysis of Data Table 1: Summarized Descriptive results of spirometric pulmonary functions Descriptive statistics ANOVA N=53 X SD Mini Maxi F Sig FVC smokers 20 4.60 .7129 3.70 5.88 14.58 .000 Non-smokers 18 5.32 .5843 4.46 6.50 sportsmen 15 5.71 .7656 4.62 8.15 Total 53 5.49 .8272 3.72 8.14 FEV1 smokers 20 3.62 .6381 2.66 4.65 32.34 .000 Non-smokers 18 4.37 .5080 3.47 5.29 sportsmen 15 4.99 .6407 3.90 6.90 Total 53 4.68 .7944 2.65 6.91 PEF smokers 20 8.64 2.057 5.15 13.15 7.22 .001 Non-smokers 18 9.86 1.440 7.62 11.9 sportsmen 15 10.38 1.560 6.94 14.9 Total 53 10.04 1.723 5.14 14.9 PIF smokers 20 5.52 1.950 2.70 10.67 7.79 .001 Non-smokers 18 7.30 1.889 4.51 10.26 sportsmen 15 7.38 1.517 4.10 12.00 Total 53 7.06 1.771 2.70 12.00 EVC smokers 20 4.46 .6709 3.76 5.76 19.585 .000 Non-smokers 18 5.19 .6532 4.35 6.76 sportsmen 15 5.70 .7357 4.41 7.90 Total 53 5.43 .8379 3.76 7.90 ERV smokers 20 1.77 .6692 .55 3.67 6.341 0.003 Non-smokers 18 1.84 .6601 .70 2.55 sportsmen 15 2.26 .5578 .84 5.15 Total 53 2.12 .6229 .82 5.15 IRV smokers 20 1.76 .6425 .36 2.80 9.83 .000 Non-smokers 18 2.34 .5700 1.36 3.51 sportsmen 15 2.50 .5740 1.12 4.25 Total 53 2.36 .6343 .36 4.25 IVC smokers 20 4.21 .6529 3.33 5.31 16.36 .000 Non-smokers 18 4.92 .6112 4.13 6.42 sportsmen 15 5.31 .7097 4.19 7.37 Total 53 5.09 .7867 3.33 7.37 MVV smokers 20 148.15 26.970 111.20 216.99 16.41 .000 Non-smokers 18 164.93 28.53 127.90 212.00 sportsmen 15 187.52 25.34 124.05 259.00 Total 53 178.00 29.88 111.15 259.00 The outcome of this investigation highlights the influence of smoking on pulmonary function. Smoking of tobacco on smokers lessens all the average values of lung function tests compared with non-smokers as well as sportsmen. This can be thought to be that as a result of smoking, the smaller airways and parenchyma are mainly effected areas showing the pathologic variations in the lung capacity (Honeybourne, et al, 1998). The evaluation of the arithmetic means for three groups was made by Analyses of Variance. The results of ANOVA (Table 1) showed statistically differences between treated groups in each measured spirometric variable.  Figure 2: Resting pulmonary function characteristics for male and female subjects Mean (± s.e.m.) Range One-tail t test P value Female Male FVC (l) Male 5.57 ± 0.29 4.57–6.59 0.13 - 104 ± 5 Female 5.12 ± 0.23 3.96–5.93 115 ± 4 97 ± 4 FEV1.0 (l) Male 4.66 ± 0.30 3.50–6.55 0.59 - 106 ± 5 Female 4.14 ± 0.12 3.64–4.59 109 ± 3 95 ± 2 FEV1.0/FVC (%) Male 82 ± 3 78–95 0.48 - 100 ± 3 Female 84 ± 6 74–96 99 ± 3 90 ± 3 RV (l) Male 1.57 ± 0.16 1.24–2.35 0.32 - 104 ± 5 Female 1.46 ± 0.16 1.03–2.45 93 ± 7 97 ± 7 TLC (l) Male 7.23 ± 0.38 5.89–9.02 0.11 - 107 ± 4 Female 6.58 ± 0.34 5.17–8.24 113 ± 5 98 ± 4 From the data above it is evident that women have a smaller lung capacity than that of men. Further investigation showed that even though they may be of the same height and age women still poses a smaller capacity. This can be attributed women have a small thoracic cavity compared to men. The volume of the thorax is related to the square of the radius, so females have much smaller lungs than men (Greenberger, Wider, & Society for Womens Health Research, 2006). Figure 3: Resting pulmonary function characteristics by height Peron’s Height Maximum Air Flow (L/MIN) trial 1 Maximum Air Flow (L/MIN) trial 2 5’2 352 358 5’3 365 379 5’4 403 405 5’5 483 480 5’6 546 550 5’7 580 577 5’8 600 605 5’9 625 626 5’10 660 658 5’11 677 680 6’0 695 692  Form the data above it is evident that taller individuals have a larger lung capacity. The average for individuals at the height of 5’2 is 355 as the average of individuals with 6’0 is 693. This can be attributed to the fact that taller people have the thoracic cavity size is bigger (Behera, 2010). Despite its limited attention, age is also a determining factor in lung capacity. As one ages, their thoracic spines "shrink". Consequently, a 6-foot tall 70-year old male has smaller lungs than a 6-foot tall 25-year old male hence showing variation because of aging on lung function (Raff, 2003). The hypothesis behind aging is associated with lessening in chest wall compliance and surged air trapping. The drop in FEV1 with age probably has a nonlinear stage with acceleration in degree of decline beyond the age 70 years. There is a rise in airspace size with aging emanating from loss of secondary tissue. Further investigation shows respiratory muscle strength declines with age and much more so in men than in women (Greenberger, Wider, & Society for Womens Health Research, 2006). In conclusion, several individuals are aware of aspects that may hinder the lung optimal functioning capacity. The most attributed cause to reduced lung functioning is related to smoking, lack of exercise, age of an individual, body mass and height. All this factors are put to test in this paper and show considerable proving results, individuals who smoke have a smaller lung capacity than those who don’t, as seasoned athletes have a larger capacity than individuals who do not train. Furthermore, generally women have a smaller lung capacity than men, as do taller individuals. Despite age being lesser recognized, it also determines lung capacity as one gets older they lose a certain strength in their lungs to hold more air. References Behera, D. (2010). Textbook of pulmonary medicine. New Delhi: Jaypee Brothers Medical Pub. Greenberger, P., Wider, J., & Society for Womens Health Research. (2006). The savvy woman patient: How and why sex differences affect your health. Sterling, Va: Capital Books Honeybourne, J., Hill, M., & Wyse, J. (1998). PE for you. Cheltenham, UK: Stanley Thornes. Neder, J. A., Andreoni, S., Castelo-Filho, A., & Nery, L. E. (1999). Reference values for lung function tests. I. Static volumes. Brazilian Journal of Medical and Biological Research, 32, 703–717. Raff, H. (2003). Physiology secrets. Philadelphia, PA: Hanley & Belfus. Read More