|Year : 2016 | Volume
| Issue : 2 | Page : 49-51
An Indian study of postural variation in peak expiratory flow rates in healthy, adult, male participants
Ajith Pakkala1, Amrith Pakkala2
1 Acharya Group of Institutions, MVJ Medical College & Research Hospital, Bengaluru, Karnataka, India
2 Department of Physiology, MVJ Medical College & Research Hospital, Bengaluru, Karnataka, India
|Date of Submission||06-Mar-2016|
|Date of Acceptance||31-Mar-2016|
|Date of Web Publication||21-Oct-2016|
No. 40, SM Road 1st cross, T. Dasarahalli, Bengaluru 560 057
Source of Support: None, Conflict of Interest: None
Peak expiratory flow rate (PEFR) reflects the strength and condition of respiratory muscles and the degree of airflow limitation in large airways. PEFR showing postural variation that follows a specific pattern in asthmatics and healthy individuals has been identified. Adequate data are not available for postural variation in normal individuals who are students of professional courses with a sedentary lifestyle. Lung volumes in normal individuals were significantly higher in the standing position. Some studies have reported that in healthy participants spirometric indices were higher while standing in comparison with the sitting position, whereas other studies have reported no differences between spirometric values obtained in the lying, sitting and standing positions. Hence, this study was undertaken to study the postural variation in PEFRs in healthy, adult, male participants in south India.
Materials and methods
PEFR was recorded in 50 adult, healthy, male participants aged 18–23 years who were students of professional courses. Mini Wright’s peak flow meter was used to measure the PEFR. Three readings were taken in the standing and lying positions. The best of the three recordings was considered as the final value.
PEFR was decreased while lying down compared with standing in the participants studied, and the quantum of difference was noted.
With postural changes, the PEFR significantly differs on the basis of whether the measurements are taken in the standing or in the lying posture in healthy participants. The effect of posture may be of importance in recording PEFR, and changing to a better posture may be especially useful for those with weak expiration.
Keywords: peak expiratory flow rate, postural variation, south indian male
|How to cite this article:|
Pakkala A, Pakkala A. An Indian study of postural variation in peak expiratory flow rates in healthy, adult, male participants. Al-Azhar Assiut Med J 2016;14:49-51
|How to cite this URL:|
Pakkala A, Pakkala A. An Indian study of postural variation in peak expiratory flow rates in healthy, adult, male participants. Al-Azhar Assiut Med J [serial online] 2016 [cited 2017 Jun 28];14:49-51. Available from: http://www.azmj.eg.net/text.asp?2016/14/2/49/192645
| Introduction|| |
Adequate data are not available for postural variation in peak expiratory flow rates (PEFRs) in normal individuals who are students of professional courses with a sedentary lifestyle. The present study was undertaken to study the postural variation in PEFRs in healthy, adult, male participants in south India.
PEFR is one of the pulmonary function parameters that provide a quantifiable measure of lung function. It is relatively a simple and easy procedure to evaluate respiratory function when compared with pulmonary function testing. Peak expiratory flow is the measurement of the movement of air into and out of the lungs during various breathing manoeuvres .
Owing to postural changes, lung volumes in normal individuals are significantly higher in the standing position . Some studies have reported that in healthy participants spirometric indices are higher in the standing position in comparison with the sitting position , whereas other studies have reported no differences between spirometric values obtained in the lying, sitting and standing positions .
| Aim and objective|| |
This study was undertaken to determine the postural variation in PEFRs in healthy, adult, male participants in south India.
| Materials and methods|| |
The present study was conducted at the Acharya Institute, Bengaluru, India. A total of 50 apparently healthy, sedentary male participants aged 18–23 years, who were students of professional courses, were included. Mini Wright’s peak flow meter was used to measure the PEFR. Three readings were taken of PEFR in the standing and lying postures. The best of the three recordings was taken as the final value.
Ethics clearance was obtained from the institutional ethics committee.
Before starting the actual study, participants were briefed about the protocol, and informed consent was obtained. Thorough history regarding suitability as per the above inclusion and exclusion criteria was elicited. Basic clinical examination was performed to rule out any cardiopulmonary or other illness.
Precautions observed during the manoeuvre.
- It was ensured that the individual was comfortable and relaxed.
- Apparatus were sterilized and cleaned properly.
- Participants were trained adequately to perform different manoeuvers.
- Individuals were instructed to hold the instrument in such a way that the hand did not obstruct the movement of the pointer.
- The pointer was kept at the lower-most level. Both nostrils were clipped while blowing into the equipment.
BMI was calculated from the measured height and weight of the individuals using the following formula:
Body surface area
Body surface area (BSA) was calculated by using Dubois’ formula as follows:
To analyse the diurnal variation of PEFR, the maximum value of the three recordings was considered as the final value.
PEFR was measured in the standing and lying positions and analysed using one-way analysis of variance followed by Tukey’s test with P value less than 0.05 as the level of significance.
| Results|| |
The anthropometric values of the participants are given in [Table 1]. On analysis of the PEFR records of individual participants, it was observed that there was an overall dip in PEFR values in the lying down posture ([Table 2]).
|Table 2: Mean PEFR values in the standing and lying postures for male participants|
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| Discussion|| |
In this study, postural changes of healthy males were studied. Our results showed that PEFR decreased in the lying position compared with the standing position in the male participants studied (P<0.05). These study findings are in contrast to the findings reported by Baduraddin et al. . They have reported that there was no significant difference in PEFR in the standing, sitting and lying positions.
Our study findings are similar to the reports of Fiz et al.  who reported that maximum inspiratory and expiratory pressure values decreased in the supine posture compared with standing and sitting positions.
In the erect posture, the diaphragm descends; therefore, the capacity of the thoracic cage increases. In the supine position, the diaphragm is pulled upwards because the abdominal viscera push the diaphragm. Therefore, the capacity of the thoracic cage decreases. Hence, vital capacity is greater in the erect posture than in the supine position. In the supine position, because of elimination of the effect of gravity, the blood flow to the lungs increases. This decreases vital capacity. In the standing posture, blood is pooled in the lower extremities; therefore, venous return decreases. This decreases pulmonary blood flow, and thus vital capacity increases while standing.
Increased lung volumes in the standing position appear to be related to the increased thoracic cavity volume . Increased lung volume leads to greater elastic recoil. Following a deep inspiration (as in preparation for a maximal expiratory manoeuvre), a larger amount of potential energy is stored in the tissue of the chest wall. Further, the contracting diaphragm increases pressure on abdominal contents pushing them forward and distending the abdominal cavity. This places the abdominal muscles at a slight stretch. Expiratory muscles attain their optimal length during standing, and at more stretched lengths the abdominal muscles may be more capable of stronger contractions, and thus help in generating higher maximum expiratory pressure.
During a forced expiration while standing, the greater recoil of the lungs and chest wall is combined with higher pressures generated by abdominal contraction. This combined action pushes the air at high speeds through narrowing airways, resulting in the higher maximum expiratory pressure and PEFR. Other factors that may have influenced the results in the standing position could include individual comfort and a higher arousal level.
Limitations of this study
The sample size was limited and only males were included.
The duration was only for 3 months.
| Conclusion|| |
In postural changes, PEFR measurements significantly differ on the basis of whether the measurements are taken in the standing or in the lying posture in healthy participants. Studying the effect of posture may be significant in recording PEFR, and changing to a better posture may be especially useful for those with weak expiration.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
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Appel M, Childs A, Healey E, Markowitz S, Wong S, Mead J. Effect of posture on vital capacity. J Appl Physiol (1985) 1986; 61:1882–1884
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Badaruddin M, Uddin MB, Khalun MF, Ahmad K. Study on peak expiratory flow rate in different positions. Dinajpur Med Col J 2010; 3:17–18.
Fiz JA, Aguilar X, Carreres A, Barbany M, Formiguera X, Izquierdo J, Morera J. Postural variation of the maximum inspiratory and expiratory pressures in obese patients. Int J Obes 1991; 15:655–659.
[Table 1], [Table 2]