|Ahead of print publication
Immediate effect of pranava pranayama on oxygen saturation and heart rate in healthy volunteers: A single-blinded, randomized controlled trial
Meena Ramanathan1, Ananda Balayogi Bhavanani2
1 Deputy Director and Associate Professor, Centre for Yoga Therapy Education and Research (CYTER) of Sri Balaji Vidyapeeth (SBV), Puducherry, India
2 Director and Professor, Centre for Yoga Therapy Education and Research (CYTER) of Sri Balaji Vidyapeeth (SBV), Puducherry, India
|Date of Submission||24-Jan-2022|
|Date of Decision||11-Apr-2022|
|Date of Acceptance||29-Apr-2022|
|Date of Web Publication||26-Dec-2022|
Ananda Balayogi Bhavanani,
Centre for Yoga Therapy, Education and Research, Sri Balaji Vidyapeeth, Pillayarkuppam, Puducherry - 607 402
Source of Support: None, Conflict of Interest: None
Introduction: Yoga is known to promote health and wellness in all. Pranava Pranayama is a useful sound based yogic breathing technique with reported benefits such as potentiating vagal tone. Subjects and Methods: This single blinded randomized self-controlled cross-over study was done with 58 participants. The immediate effect of Pranava Pranayama on saturation of oxygen in the blood (SpO2) and heart rate (HR) was determined before and after intervention using pulse oximeter. To avoid extraneous influences due to recording on different days, one half of the subjects were randomized to perform quiet sitting on day 1 while other half did Pranava Pranayama which was then reversed on day 2. Results: Intra group comparison showed significant changes (p < 0.001) in both SpO2 and HR following Pranava Pranayama whereas in the quiet sitting group, there was an insignificant fall in the SpO2 readings but HR was found significant (p < 0.001). Intergroup comparison showed significant differences between groups (p-0.032). Discussion: Cardiovascular changes following Pranava Pranayama may be as a result of audible chanting improving baroreflex sensitivity along with increased endogenous nitric oxide production. This promotes vasodilatation resulting in reduction of BP. The decrease in vascular resistance and an increase in capillary perfusion results in increased oxygen saturation with lesser demand on the heart. Conclusion: This study provides evidence that Pranava Pranayama is an effective technique in enhancing SpO2 and our findings may have therapeutic applications especially in the current pandemic situation.
Keywords: COVID-19, nada pranayama, pandemic, pulse oximetry, SpO2, yoga therapy
|How to cite this URL:|
Ramanathan M, Bhavanani AB. Immediate effect of pranava pranayama on oxygen saturation and heart rate in healthy volunteers: A single-blinded, randomized controlled trial. Med J DY Patil Vidyapeeth [Epub ahead of print] [cited 2023 Mar 24]. Available from: https://www.mjdrdypv.org/preprintarticle.asp?id=365373
| Background of the Study|| |
Since the outbreak in December 2019, coronavirus disease 2019 (COVID-19) has been raging all over the world. This virus damages patients' lung function and reduces their blood oxygen saturation causing complications. Poor mental health conditions are known to increase the risk further.
Pranayama is known to regulate mental as well as lung function to combat virus-specific immune response. Yoga could be a simple and most beneficial home-based practice for the prevention and management of COVID-19, to achieve a state where mind becomes calm and is enabled to move away from the hazardous effect due to this pandemic. World has the need for Yoga 'now' more than ever as this ancient Indian practice is helping a large number of patients across the globe combat the disease.
In this current scenario, we selected this easy and effective Pranayama technique, the Pranava Pranayama as the intervention, as it could be useful and extremely beneficial in multiple ways to many patients admitted in various hospitals due to this dreaded virus, in a simple and cost-effective manner as well as to the whole of humanity by alleviating stress on the whole.
| Introduction|| |
Yoga, the science of the mind, educes positive qualities and curbs negative patterns of destructive, disruptive and distractive thoughts and emotions springing up constantly enabling the individual to transcend all limitations. Yoga promotes a balanced state of body, mind, and emotions, enabling us to take charge of our own life, thus promoting holistic health for each and every one of us. Yoga is an experiential science and it is important to know why we do, what we do, to understand and experience this wholesome and integral science of life that deals with multidimensional aspects of health in both the individual and society. It has been found that consistent practice of Yoga increases the lung's airflow, air capacity, stamina and efficiency. Pranayama, the fourth limb of Ashtanga Yoga, promotes a sense of ease, peace and tranquillity and is an easy form of involved breathing that enhances the awareness of the entire process of breathing. Pranayama harmonizes and rejuvenates body, mind, emotions facilitating relaxation response and thereby improving neuromuscular-physiological functioning, restoring the cardiovascular (CV) rhythms of the heart. Regular training enhances central processing ability that may be utilized to promote agility, attentiveness, self-awareness and coordination. Pranayama is a simple and safe non-pharmacological intervention that has great potential to bring about many beneficial positive changes.
Pranava Pranayama has unlimited healing potential and is useful in virtually all disorders. It brings about harmony of body, emotions, and mind. This is the cornerstone of breath therapy and produces good health, happiness, and longevity for those suffering from various disorders. Methodology has been given in the form of a flow chart in [Figure 1]. A sensation of vibration is experienced during audible 'OM' chanting. This has the potential for vagal stimulation through its auricular branches and the effects on the brain thereof. Pranayama produces relaxed state and in this state, parasympathetic activity overrides sympathetic activity and increases cardiac-vagal baroreflex sensitivity, improves oxygen saturation, lowers blood pressure, pulse rate, and reduces anxiety. Slow breathing improves oxygenation in normoxia; however, the effects could be more pronounced in hypoxemia and hypoxia.
Saturation of oxygen in the blood (SpO2) is one of the most important vital signs to define blood oxygen content and oxygen delivery. Moreover, determining its value is considered an imperative task for healthy and sick people. The most common method to measure the SpO2 vital sign is by using the pulse oximeter. This information might save lives. Lack of sufficient oxygen in blood may be related to cardio-respiratory disorders due to which there is an inability to get sufficient oxygen for their body cells. This disorder could be brought under control in addition to other complications associated with this along with increasing oxygen in blood.
Pulse oximetry (used more in emergency department to determine the baseline oxygenation of a patient in respiratory distress) is a class II device with FDA registration designed to measure SpO2 and pulse rate in an innovative and non-invasive manner., Typical ranges of the SpO2 vital sign vary between 95% and 100%. However, when patients have some medical troubles such as CV, chronic diseases, and pneumonia, the level of SpO2 may drop rapidly. Ranges between 95% and 90% are considered to be low but with no evidence of impairment. Moreover, when the level of SpO2 gets lower than 90%, then this causes acute respiratory failure., Hence, it is imperative that Pranava Pranayama, an integral component of Yoga Therapy with its immense vibrational potential would improve SpO2 and reduce HR in normal volunteers. The importance of this study is that it will pave way for application of this simple and effective Pranayama technique in patients with low SpO2 values and enable determination of prognosis in individuals. There is a paucity of literature on efficacy of Pranava Pranayama on enhancing oxygen levels in blood; the present study was done to evaluate the effectiveness of this Pranayama technique in normal healthy volunteers.
| Subjects and Methods|| |
The present study was conducted with participants attending Yoga sessions at Centre for Yoga Therapy, Education and Research (CYTER) of Sri Balaji Vidyapeeth (SBV). Ethical approval was received from Institutional Human Ethics Committee of Mahatma Gandhi Medical College and Research Institute, SBV, Pondicherry (#MGMCRI/IRC/04/2020/69/IHEC/202). After fulfilling the inclusion and exclusion criteria, they were oriented about the study and consent was taken. There were two study groups, Group A and Group B. Those participants randomised to group A performed the Pranava Pranayama while those allotted to group B were sitting quiet focusing on their breath for the same period of time. The consecutive day, they were crossed over and those who performed Pranava earlier did the quiet sitting and vice versa. All the participants whose data were considered for analysis completed both the interventions. Those who could not complete both techniques on consecutive days were considered as drop outs from the study. SpO2 and HR were recorded for all participants before and after the intervention using a pulse oximeter.
The study is a single blinded randomized self-controlled study done on two consecutive days for all the participants. The investigator was blinded about the details of the participants, details of the randomization of techniques, data collection, and the data entry. It was done by the research scholars of CYTER. Instructions for performing Pranava Pranayama were given by the Yoga Instructor of CYTER to ensure similar rhythm and count of breath for all participants.
This study started with 74 healthy participants attending Yoga sessions at CYTER but only 58 (19M and 39F whose mean age was 20.48 ± 3.80 yrs) of them completed the study. 16 participants were considered as dropouts [Figure 1]. Reliability and reproducibility of the observations was assessed to rule out any changes that could be resulting from 'practice effect' and the two techniques chosen for the study were reversed. To avoid any extraneous influences due to the recording on different days, one half of the subjects (randomly divided by box randomisation – blocks of 4) performed non-intervention period recordings on day 1, while the other half did the Pranava Pranayama recordings. This was then reversed on day 2. The study was done at the Patanjali Yogashala of CYTER at the SBV campus, Puducherry. The participants were instructed to empty their bladder and bowels before the data collection and to finish their breakfast at least 2 hours earlier. All the data were collected between 10 am and 12 noon in a temperature controlled room. The participants were made to sit in a straight backed chair with their eyes for two minutes closed before data was collected. SpO2 and HR were recorded before and after intervention (Pranava Pranayama) and control period (quiet sitting) on both the days.
SpO2 and HR were recorded on the middle finger of the right hand using a pulse-oximeter, sitting on a chair while their hand rested on the table in front. The highest SpO2 value can be taken as the most accurate value that reflects the arterial oxygen saturation. Basaranoglu et al. after their analysis concluded that SpO2 measurement from the right middle finger and right thumb have the most accurate value that reflects the arterial oxygen saturation with the pulse oximetry. Hence in this study, the right hand middle finger was used for all the participants to collect the SpO2 and HR values.
Procedure of Pranava Pranayama: It is made up of 4 parts
- The first part is known as Adham Pranayama (the abdominal or lower chest breathing). To perform this, we adopt Chin Mudra in both our hands; with index fingers and thumbs of both hands touching each other making a circle, and the other three fingers are held stretched straight and kept together. Place both your hands with Chin Mudra on the thighs with the palms facing down. Inhale to a count of 6 and when you exhale, make the Nada or the sound of aaaa opening the mouth.
- The second part is known as the Madhyam Pranayama (the thoracic or mid-chest breathing). To perform this, we adopt Chinmaya Mudra in both our hands with index fingers and thumbs of both hands touching each other making a circle, and the other three fingers are curled inward to touch the palms. Place both hands with Chinmaya Mudra on the thighs with the palms facing down. Inhale to a count of 6 and when you exhale, make the Nada or the sound of uuuu as you pucker your lips like a crow's beak.
- The third part is known as Adhyam Pranayama (the clavicular or upper chest breathing). To perform this, we adopt Adhi Mudra in both our hands with the thumb folded into the palm and the other four fingers curled around the thumb as if you are making a fist. Keep the Mudra on your thighs with the palms facing down. Inhale to a count of 6 and when you exhale, make the Nada or the sound of mmmm feeling the vibrations resonating.
- To perform the last and fourth part of Pranava Pranayama, join the earlier three parts of this practice into a complete Yogic breath, known was Mahat Yoga Pranayama. To perform this, we adopt Adhi Mudra in both our hands with the thumb folded into the palm and the other four fingers curled around the thumb as if you are making a fist. Then turn the hands upwards, with knuckles of your right and left hands touching each other. Keep your hands in front of the nabhi or the navel region. This Mudra is known as the Brahma Mudra. Inhale to a count of 6 and when you exhale, make the Nada or the sounds of aaaa…uuuu…mmmm making it the complete cycle of one round of the Pranava Pranayama.
The control intervention was quiet sitting focusing on the breathing. The participants were made to sit on the chair, eyes closed and holding the fingers of both hands intertwined in Yoga Mudra on their lap.
Pulse oximeter model description: LK87 - SKUSEN027, with dimensions - 5.7 x 3.1 x 3.2 cm with measuring range of oxygen saturation: 70~100% and reliability of ± 2% accuracy. Pulse Rate of 30~240 bpm (+/- 2% accuracy) providing accurate and reliable results.
All data passed normality testing by Kolmogorov-Smirnov (KS) test and hence intra-group comparisons of pre- and post-study data was done using Student's paired 't' test while intergroup comparisons between groups was done using Student's unpaired 't' test. P values less than 0.05 were considered to indicate significant differences between the means.
| Results|| |
The details regarding age and gender are given in [Table 1] and the results of the study have been given in [Table 2]. To nullify the baseline differences, delta% was calculated. Intra group comparisons showed highly significant changes (p < 0.001) in both SpO2 and HR following Pranava Pranayama whereas there is an insignificant fall in the SpO2 readings but HR was found significant (p < 0.001) after quiet sitting. Inter-group comparison showed significant difference in SpO2 between groups (p = 0.032) in Pranava Pranayama.
|Table 2: Pre- and post-effect of Pranava Pranayama and quiet sitting on oxygen saturation levels (SpO2) and heart rate (HR) in 58 healthy volunteers|
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Student's paired t-test was used to compare data that passed normality testing by Kolmogorov-Smirnov test. P < 0.05, ** P < 0.01 and *** P < 0.001 by paired t-test for intra group comparisons. Actual P values are given for unpaired t-test between groups. Δ% is calculated using the formula - 100 x (Post-Pre)/Pre-data values
| Discussion|| |
One of the biggest challenges today is the dropping oxygen levels for those suffering from COVID. The present study was planned since there is surge of emerging evidence that yoga as an adjuvant therapy can have significant beneficial effects in patients affected by COVID and many others suffering from respiratory distress due to low oxygen levels in blood. To the best of our knowledge, this study is the first one of its kind to assess the immediate effect of Pranava Pranayama in improving oxygen levels in normal healthy volunteers and the results obtained have revealed positive and significant effect.
Yoga practice reduces stress, physical tension, muscle tightness, and increases overall well-being. Pranayama is often erroneously called or related only as deep breathing. The actions are so unhurried in the practice of Pranayama that there is adequate time for every alveoli to take in oxygen and energy is also not allowed to forcefully exit from the system. That is the reason why exhalation is very slow. This gives time for the system to continue to absorb energy even during the exhalation phase, better blood circulation, and effective oxygenation, better performance of the respiratory system enhancing the strength of the lungs. Evidence from studies have established and confirmed that Yoga practices promote reduction of sympathetic and increase of parasympathetic nervous activity. Numerous studies in health psychology and clinical treatment have demonstrated that deep breathing is an effective relaxation technique in complementary and alternative medicine, with beneficial effects on physical, physiological, and mental health.,
Evidence showed that even a single breathing practice significantly reduces blood pressure (BP), increases HR variability and oxygenation enhances pulmonary function, improves cardio-respiratory fitness and respiratory muscle strength. Bhavanani et al. determined that Pranava Pranayama was effective in reducing HR, systolic pressure (SP) and other derived CV indices in hypertensive patients which was postulated to have been due to normalization of autonomic CV rhythms as a result of increased vagal modulation and/or decreased sympathetic activity and improved baroreflex sensitivity (BRS) along with an augmentation of endogenous nitric oxide (NO) production.
Decrease in oxygen saturation and increase in pulse rate and HR variability may be either from impairment of autonomic nervous cardiac control or in response to hypoxia. The rise in HR in response to anoxemia (a condition of subnormal oxygenation of the arterial blood) showed an inverse of oximeter readings. Blood carries oxygen in two forms, the majority is bound to haemoglobin (oxy-haemoglobin) and the rest is dissolved in the aqueous phase of blood (the plasma). The dissolved fraction is dependent upon the partial pressure of oxygen. As the partial pressure increases, the dissolved fraction of oxygen increases that is measured by oximetry. Efficiency of ventilation for oxygen may be improved by changing the respiratory pattern. There may be greater vagal activity when the expiration is doubled or tripled such as in Pranava Pranayama. These changes are attributed to influence respiratory centre and/or pulmonary stretch receptors on vagal control of the heart. Mantra Japa especially Omkar is very useful and known to attenuate the limbic over activity. Pranava Pranayama is extremely useful in inducing relaxation response along with promoting healing from within. It was predicted by Kalyani et al. that 'OM' chanting would evoke neuro-hemodynamic correlates promoting deactivation of the limbic brain regions, amygdala, hippocampus, anterior cingulate cortices and thalamus. They observed vagal nerve stimulation with OM chanting indicating relaxation.
This study ascertains that Pranava Pranayama, the Nada-based (sound-based) breathing has effectively increased oxygen absorption leading to enhanced BRS which may be due to several interrelated factors. This finding has been well supported by studies showing the increase in arterial oxygen partial pressure increases BP, which in turn could stimulate the baroreceptors and improve the BRS gain. This was recently observed in healthy and diabetic subjects. The increased oxygen absorption may inhibit the chemo-reflex and by this reciprocal relationship increase BRS. Bernardi et al. demonstrated that slow breathing reduced chemo-reflex sensitivity to both hypoxia and hypercapnia. It is well understood that the chemo-reflex is a mechanism to stabilize blood pH by increasing ventilation.
Gokhale et al. concluded that practice of Kapalabhati Pranayama increases oxygen saturation and diastolic BP immediately even in novices and that the diaphragm is vigorously manipulated and enhances the better oxygenation. Yogic practices, especially Pranayama, with its unique characteristics are an asset for preventive care as well as preserving health. In this study we found significant improvement on blood oxygen level which has also been established earlier by Sharma et al. who found similar results with Yoga Therapy. It can be further confirmed that Pranava Pranayama is very effective in improving blood oxygen deficiency. Breathing exercises may also improve arterial oxygenation by increasing alveolar volume and gas exchange at the alveolar capillary membrane level.
The possibility that a decrease in SpO2 leading to an increase in BP had been previously investigated by Kishimoto et al. If BP becomes too low, body will not receive enough oxygen to carry out its normal functions causing difficulty with breathing. Elevated BP can damage arteries by making them less elastic with decreased flow of blood and oxygen to heart. On the contrary, vasodilatation is a mechanism to enhance blood flow to areas of the body that are lacking oxygen and/or nutrients. The vasodilatation causes a decrease in systemic vascular resistance and an increase in blood flow, resulting in a reduction of BP. In response to a need for oxygen or nutrients, tissues can release endogenous vasodilators. The result is a decrease in vascular resistance and an increase in capillary perfusion.
NO is a signalling molecule that is involved in several physiological and pathological processes and is important for many aspects of health, specifically for vasodilatation (relaxes the inner muscles of the blood vessels promoting increased circulation). NO affects two key aspects of O2 supply and demand; regulates vascular tone and blood flow. A recent review by Buerk assessed the role of NO in regulation of micro vascular oxygenation and has long since been known as endothelium-derived relaxing factor that modulates BP. NO enhances pulmonary vascular resistance and improves ventilation–perfusion ratio in the lung along with relaxation of bronchial smooth muscles, hence oxygen uptake is increased and provides relief in respiratory distress. It has been proved that humming increases NO expression dramatically as a consequence of oscillating sound wave and affecting air exchange in the sinus. Eby explained humming as a sonic cleanser, cures the infection of respiratory tract. It is estimated that humming increases the endogenous generation of NO level by 15-fold as compared with the quite exhalation.
Pranava Pranayama, having a component of humming in it, enhances the expression of NO, increases carbon dioxide output by extended exhalation and alkaline pH preventing coagulopathies and morbidity. NO improved severe hypoxia and shortens the period of hospital stay and also increases the survival rate. In addition to these cost-effective techniques along with the medical management will help patients of respiratory disorders and other CV conditions. Our study further substantiates the claim that Pranava Pranayama is beneficial in enhancing oxygen saturation in the blood apart from bringing down the pulse rate in normal subjects. In future we are planning to extend this study further with more number of subjects and with other parameters on healthy subjects as well as patients.
The present study is limited by the smaller sample size. We had to adopt the convenient sampling method due to logistical reasons. It was also limited to a single centre and only two parameters were taken for analysis. Further studies need to be done in future involving other related parameters to validate these preliminary results. Further, multi-centric studies that explore functional changes with correlations between such changes, psychological variables, and other biochemical markers may deepen the understanding of intrinsic mechanisms by which these changes are occurring in yoga therapy programs.
| Conclusion|| |
Our findings have potential therapeutic applications in day-to-day as well as clinical situations, especially now during the times of COVID pandemic, where SpO2 needs to be enhanced at the earliest. The significant rise in SpO2 and fall in pulse rate found in this study as an immediate effect of Pranava Pranayama signifies healthier functioning of the cardio respiratory system. We suggest that further short- and long-term studies be undertaken with Pranava Pranayama in patients to further qualitatively and quantitatively evaluate inherent mechanisms of this simple technique. The addition of such cost-effective techniques to the medical management will help patients of rhythm and other CV disorders to manage their condition more effectively.
We conclude that Pranava Pranayama is an effective technique in enhancing SpO2 and our findings have therapeutic applications especially in the current pandemic situation and is clinically valuable in patients having discrepancy in oxygen levels and pulse rate.
Support of the benevolent management and visionary administrators of Sri Balaji Vidyapeeth is gratefully acknowledged. Heartfelt gratitude is offered to Prof Dr Madanmohan, Honorary Advisor CYTER for his constant support, encouragement, and professional advice. The authors express heartfelt gratitude to Yoga instructors of CYTER Danushapnadeesh, and Sarulatha for being a part of this study and immense gratitude to students/research scholars of CYTER- Garima Setia, Sushant Singh, Chaitanya Sharma, and Raghav Rajauria for their valuable assistance during the study in randomization of the study participants, data collection and data entry.
Disclosure of ethical approval
The study was approved by the Institutional Human Ethics Committee (#MGMCRI/IRC/04/2020/69/IHEC/202) of MGMCRI, Sri Balaji Vidyapeeth, Puducherry.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Though the present work did not receive any special funding, Sri Balaji Vidyapeeth funds the CYTER and all of its activities in yoga therapy, education, and research.
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2]