DOCSLIB.ORG

The Effect of Carbon Dioxide on Airway Tone

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Effect of Carbon Dioxide on Airway Tone UNIVERSITY OF CALGARY The Effect of Carbon Dioxide on Airway Tone by Tamer Y. El Mays A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE DEPARTMENT OF CARDIOVASCULAR/RESPIRATORY SCIENCES CALGARY, ALBERTA April, 2007 © Tamer Y. El Mays 2007 UNIVERSITY OF CALGARY FACULTY OF GRADUATE STUDIES The undersigned certify that they have read, and recommend to the Faculty of Graduate Studies for acceptance, a thesis entitled “The Effect of Carbon Dioxide on Airway Tone" submitted Tamer Y. El Mays in partial fulfilment of the requirements of the degree of Master of Science. Supervisor, Dr. Francis HY Green, Dept. of Cardiovascular/Respiratory Sciences Dr. Marc J. Poulin, Dept. of Cardiovascular/Respiratory Sciences Dr. William A. Whitelaw, Dept. of Cardiovascular/Respiratory Sciences Dr. Richard J. Wilson, Dept. of Cardiovascular/Respiratory Sciences Dr. Neil Eves, Faculty of Kinesiology Date ii Abstract The Buteyko Breathing Technique (BBT) has received interest over the last few years as a non pharmacological complementary therapy for asthma. The BBT involves breath holding in order to raise PCO2 which is believed to result in broncho-relaxation and relief of asthma. Clinical trials indicate that asthmatics using BBT need less asthma medications. However, studies of the physiological basis for the theory have not yet been undertaken. The objective of this study was to determine the effects of inhaled CO2 on constricted airways in allergic asthma as well as evaluating the effects of CO2 on bronchial smooth muscle (BSM) tone in vitro. An animal model of acute on chronic asthma was developed using Brown Norway Rats immunized and challenged with ovalbumin. A biphasic asthmatic response was observed using non-invasive whole body plethysmography. Using this model, the effects of different concentrations of CO2 on the response of allergic asthma were evaluated. We found that inhaled CO2 caused a significant (p<0.001), rapid and reversible dose-dependent relaxation of constricted airways during the late phase of the asthmatic response. Furthermore, hypocapnic challenge increased bronchial smooth muscle resting tone in vitro and significantly diminished substance P-induced epithelium-dependent relaxation of bronchial smooth muscle. The smooth muscle response to hypocapnia was pH dependent and in part dependent on L-type Ca2+ channels. Our results show that CO2 is a rapid and effective bronchial smooth muscle relaxant with potential for the treatment of acute asthma in humans. These animal studies provide supportive evidence to some aspects of Dr. Buteyko’s theory. iii Acknowledgements I would like to acknowledge my supervisor, Dr. Francis Green and thank him for being a great teacher, a guide and a friend. Without him, this work would not be possible. I owe special thanks to my supervisory committee members Drs. Marc Poulin, William Whitelaw and Richard Wilson, for their guidance and support. I would like to acknowledge my colleagues in the Respiratory Research Group at the University of Calgary for their collaboration and solidarity. In our group, special thanks to Dr. Rommy Koetzler for her support and advice. The technical assistance to Marija Susnjar, Elizabeth French, Hannah Park, Tara Stapleton Artee Karkhanis and Marnie Cudmore is greatly appreciated. I would like to express my sincere gratitude to the co-operative groups involved in this work: the lab of Drs. Morley Hollenberg and Roland Auer. My special thanks to the staff of Dr Hollenberg: Dr. Mahmoud Saifedine and Zhenguo Yu, for their contributions and help through out this project. Special thanks to my friend Dr. Abdel Aziz Shaheen for his great help in statistics. My sincere thanks for my friends Dr. Ahmed Al-Sabi’ and Fateh Zaamout for their endless support and kindness. I am especially grateful to my parents, my brothers, my grandmother, and my small family; my wife and precious children for their continuous support and love. Love you all and keep blooming in the sky... Tamer Y. El Mays February, 2007 iv Dedication I dedicate this thesis to my Parents, my brothers Hesham and Amro, and my grandmother. To my dear wife Julia and my lovely children Youssef and Inas. v Table of Contents Approval Page.................................................................................................................ii Abstract......................................................................................................................... iii Acknowledgements ........................................................................................................iv Dedication .......................................................................................................................v List of Tables................................................................................................................viii List of Figures ................................................................................................................ix List of Symbols, Abbreviations and Nomenclature ........................................................xii CHAPTER ONE: INTRODUCTION ..............................................................................1 1.1 The respiratory system...........................................................................................1 1.1.1 Airways anatomy...........................................................................................1 1.1.2 Airway smooth muscle...................................................................................2 1.1.3 The respiratory circulation .............................................................................4 1.1.4 Gas exchange.................................................................................................4 1.2 Asthma ..................................................................................................................5 1.2.1 Definition ......................................................................................................5 1.2.2 Prevalence .....................................................................................................6 1.2.3 Etiology and pathogenesis..............................................................................6 1.2.3.1 Atopic asthma.......................................................................................7 1.2.3.2 Non-atopic asthma................................................................................8 1.2.3.3 Mucus plugs .......................................................................................10 1.2.3.4 Remodelling .......................................................................................11 1.2.4 Clinical manifestation of asthma ..................................................................11 1.2.5 Breathing disorders associated with asthma..................................................11 1.2.6 Treatment of asthma ....................................................................................13 1.2.6.1 Conventional treatments .....................................................................13 1.2.6.2 Alternative treatments.........................................................................16 1.3 Hypothesis...........................................................................................................20 1.4 Objectives............................................................................................................20 CHAPTER TWO: THE EFFECT OF INHALED CARBON DIOXIDE ON CONSTRICTED AIRWAYS IN AN ANIMAL MODEL OF ASTHMA ..............21 2.1 Introduction .........................................................................................................21 2.2 Materials..............................................................................................................22 2.3 Methods...............................................................................................................25 2.3.1 Whole body plethysmography......................................................................25 2.3.2 Experimental design ....................................................................................30 2.3.2.1 Baseline pulmonary function in unchallenged rats ..............................30 2.3.2.2 Experimental protocols.......................................................................31 2.3.3 Statistical analysis........................................................................................39 2.4 Results.................................................................................................................39 2.4.1 Whole body plethysmography......................................................................39 2.4.2 Blood gas analysis .......................................................................................42 vi 2.4.3 Pulmonary Function.....................................................................................44 2.4.4 Qualitative pathologic assessment of the multiple allergen-challenged model...........................................................................................................47 2.4.5 Quantitative measurements of collagen ........................................................48 2.5 Discussion ...........................................................................................................50 CHAPTER THREE: THE EFFECTS OF CARBON DIOXIDE ON BRONCHIAL SMOOTH MUSCLE TONE .................................................................................54
Load more

Recommended publications
  • Effect of the Buteyko Method on Resting Ventilation and Asthma Control in Asthma Patients
    Effect of the Buteyko Method on Resting Ventilation and Asthma Control in Asthma Patients Monique van Oosten Ritgerð til meistaragráðu Háskóli Íslands Læknadeild Námsbraut í Lýðheilsuvísindum Heilbrigðisvísindasvið Áhrif Buteyko aðferðinnar á hvíldaröndun og stjórnun astmasjúkdómsins hjá astmasjúklingum Monique van Oosten Ritgerð til meistaragráðu í Lýðheilsuvísindum Leiðbeinandi: Marta Guðjónsdóttir Meistaranámsnefnd: Marta Guðjónsdóttir, Auðna Ágústsdóttir og Björn Magnússon Læknadeild Námsbraut í Lýðheilsuvísindum Heilbrigðisvísindasvið Háskóla Íslands Mars 2017 Effect of the Buteyko Method on Resting Ventilation and Asthma Control in Asthma Patients Monique van Oosten Thesis for the degree of Master of Science Supervisor: Marta Guðjónsdóttir Masters committee: Marta Guðjónsdóttir, Auðna Ágústsdóttir and Björn Magnússon Faculty of Medicine Department of Public Health School of Health Sciences March 2017 Ritgerð þessi er til meistaragráðu í lýðheilsufræði og er óheimilt að afrita ritgerðina á nokkurn hátt nema með leyfi rétthafa. © Monique van Oosten 2017 Prentun: Háskólaprent Reykjavík, Ísland 2017 Ágrip Bakgrunnur . Buteyko meðferðin (BM) virðist breyta öndun, bæta lífsgæði og astma stjórnun hjá astma sjúklingum. Rannsóknir hafa fram að þessu ekki skilgreint nægilega vel lífeðlisfræðileg áhrif meðferðarinnar. Markmið þessarar rannsóknar er að skoða lífeðlisfræðileg áhrif BM á hvíldaröndun og stjórnun astma í hóp astmasjúklinga. Aðferð . Í þessari framskyggnu, íhlutandi rannsókn með samanburðarhópi voru astmasjúklingar mældir þrisvar sinnum í algjörri hvíld, með 6 mánaða millibili. Þeir voru paraðir miðað við aldur, kyn og líkamsþyngdarstuðul (BMI) við heilbrigðan samanburðahóp. BM var kennd eftir fyrstu 6 mánuðina. Síðan var hópnum fylgt eftir og mældur að nýju 6 mánuðum síðar. Hvíldaröndun (öndunartíðni og andrýmd (V T)), næmni öndunarstöðva metin út frá viljastýrðu öndunarstoppi, efnaskipti, og astma control spurningalisti (ACT) voru skoðuð.
    [Show full text]
  • Breathing Exercises And/Or Retraining Techniques in the Treatment of Asthma: Comparative Effectiveness Comparative Effectiveness Review Number 71
    Comparative Effectiveness Review Number 71 Breathing Exercises and/or Retraining Techniques in the Treatment of Asthma: Comparative Effectiveness Comparative Effectiveness Review Number 71 Breathing Exercises and/or Retraining Techniques in the Treatment of Asthma: Comparative Effectiveness Prepared for: Agency for Healthcare Research and Quality U.S. Department of Health and Human Services 540 Gaither Road Rockville, MD 20850 www.ahrq.gov Contract No. 290-2007-10057-I Prepared by: Oregon Evidence-based Practice Center Kaiser Permanente Center for Health Research Portland, OR Investigators: Elizabeth O’Connor, Ph.D. Carrie D. Patnode, Ph.D., M.P.H. Brittany U. Burda, M.P.H. David I. Buckley, M.D., M.P.H. Evelyn P. Whitlock, M.D., M.P.H. AHRQ Publication No. 12-EHC092-EF September 2012 This report is based on research conducted by the Oregon Evidence-based Practice Center (EPC) under contract to the Agency for Healthcare Research and Quality (AHRQ), Rockville, MD (Contract No. 290-2007-10057-I). The findings and conclusions in this document are those of the authors, who are responsible for its contents; the findings and conclusions do not necessarily represent the views of AHRQ. Therefore, no statement in this report should be construed as an official position of AHRQ or of the U.S. Department of Health and Human Services. The information in this report is intended to help health care decisionmakers—patients and clinicians, health system leaders, and policymakers, among others—make well-informed decisions and thereby improve the quality of health care services. This report is not intended to be a substitute for the application of clinical judgment.
    [Show full text]
  • For the Reversal of Chronic Hyperventilation
    For the Reversal of Chronic Hyperventilation By: Peter Kolb BSc(Eng), MSc(Med) Illustrations: Victor Lunn-Rockliffe Revision 1.2 Contents Page 1. What is Chronic Hyperventilation Syndrome? 3 2. How does CHV develop? 4 3. How does Buteyko therapy work? 4 4. What happens to patients with CHVS? 5 5. Physiological consequences of low CO2. 6 6. Immune system. 8 7. Other symptoms and disorders. 10 8. Buteyko for Asthma, 1st Clinical Trial. 12 9. Lung Function Test. 14 References 15 For more information: http://members.westnet.com.au/pkolb [email protected] 2 1. What is Chronic Hyperventilation Syndrome? Chronic Hyperventilation Syndrome [CHVS] is a vast complex of bizarre29,31,16 protean1,29,31,18 symptoms and disorders that are caused by habitually breathing too much. Technically it is not a syndrome at all since the symptoms are so variable. Not withstanding that chronic hyperventilation [CHV] has a compelling appeal as the physiological basis for the many chronic disorders we see today, mainstream medicine has consistently failed to deal with it since its discovery over 100 years ago.1,16,18,24,29 In 1975 British cardiologist, Claude Lum wrote:16 Some forty years ago Kerr, Dalton and Gliebe wrote "Patients presenting the well-known pattern of symptoms haunt the offices of physicians and specialists in every field of medical practice. They are often shunted from one physician to another, and the sins of commission inflicted upon them fill many black pages in our book of achievement.” Unfortunately I believe this to be still true today, despite the many and excellent reviews which have appeared in the intervening years.
    [Show full text]
  • Systematic Review of the Effectiveness of Breathing Retraining in Asthma Management
    Review For reprint orders, please contact [email protected] Systematic review of the effectiveness of breathing retraining in asthma management Expert Rev. Respir. Med. 5(6), 789–807 (2011) John Burgess1, In asthma management, complementary and alternative medicine is enjoying a growing Buddhini Ekanayake1, popularity worldwide. This review synthesizes the literature on complementary and alternative Adrian Lowe1, medicine techniques that utilize breathing retraining as their primary component and compares David Dunt2, evidence from controlled trials with before-and-after trials. Medline, PubMed, Cumulative Index 3 to Nursing and Allied Health Literature and the Cochrane Library electronic databases were Francis Thien and searched. Reference lists of all publications were manually checked to identify studies not found 1 Shyamali C Dharmage* through electronic searching. The selection criteria were met by 41 articles. Most randomized 1Centre for Molecular, Environmental, controlled trials (RCTs) of the Buteyko breathing technique demonstrated a significant decrease Analytic and Genetic Epidemiology, in b -agonist use while several found improvement in quality of life or decrease in inhaled Melbourne School of Population 2 Health, The University of Melbourne, corticosteroid use. Although few in number, RCTs of respiratory muscle training found a Victoria 3010, Australia significant reduction in bronchodilator medication use. Where meta-analyses could be done, 2Centre for Health Program Evaluation, they provided evidence of benefit from yoga, Buteyko breathing technique and physiotherapist- Melbourne School of Population led breathing training in improving asthma-related quality of life. However, considerable Health, The University of Melbourne, Victoria 3010, Australia heterogeneity was noted in some RCTs of yoga. It is reasonable for clinicians to offer qualified 3Department of Respiratory Medicine, support to patients with asthma undertaking these breathing retraining techniques.
    [Show full text]
  • Effectiveness of Buteyko Method in Asthma Control and Quality of Life of School-Age Children | 1
    Effectiveness of Buteyko Method in Asthma Control and Quality of Life of School-age Children | 1 Effectiveness of Buteyko Method in Asthma Control and Quality of Life of School-age Children Romella C. Lina, Matthew Daniel V. Leysa, Zarah DF. Libozada, Maria Francesca I. Lirio, Angelo A. Liwag, Gabriel D. Ramos, Margaret M. Natividad, RN, M.Ed. College of Nursing, University of Santo Tomas, España, Manila, Philippines 1015 ______________________________________________________________________________ ABSTRACT Background: Asthma affects not only the physiological status of school-age children but also their over- all functional capacity. This may eventually impede personality development if not managed promptly and adequately. Objective: This study aimed to determine the effectiveness of Buteyko Method in improving asthma control and quality of life of school-age children. Methods: This study utilized a pre-test – post test design to measure the changes in asthma control and quality of life after the administration of Buteyko Method. Fourteen (14) subjects diagnosed with bronchial asthma, age 7 - 11 years old participated in the study. They were equally divided into two groups: the control group received no intervention while the experimental group was asked to attend sessions of Buteyko Method lecture and demonstration. The experimental group was visited for three (3) consecutive weeks to monitor their progress and compliance. Moreover, each group was asked to answer ACQ pre- and post-intervention and PAQLQ before the start of the intervention phase and every week during the follow-up visits. Results: In comparing the asthma control pre-test and post-test mean scores of the control group, no significant difference was noted (p=0.177) while the experimental group showed a significant difference after the administration of Buteyko Method (p=0.002).
    [Show full text]