Oxygen Caution
There are many references warning about use of supplemental Oxygen (Oxygen given without use of assisted/mechanical ventilation) in individuals living with Neuromuscular Disease (NMD) who have weakened breathing muscles. Sadly, many individuals and some health care providers are not aware of this risk, and this can lead to significant worsening of the individual's symptoms. In extreme cases, it can cause death.
How can supplemental Oxygen be dangerous?
There are two parts of respiration: the mechanics of breathing and the exchange of Oxygen (O2) for Carbon Dioxide (CO2). When inhaling air, the diaphragm and intercostal muscles contract, the diaphragm moves down, and the ribs move up. This creates space within the chest, and air rushes in to fill this space (Oxygen). When the air rushes in, the air goes to the lungs where this Oxygen (O2) is exchanged for Carbon Dioxide (CO2). Oxygen then passes into the blood and travels into the hemoglobin to the cells. The muscles of the chest relax and the air, now filled with CO2, is pushed out of the body. Breathing happens automatically, and it is regulated by the respiratory center in the brainstem. When the body has too much CO2 or not enough O2, the brainstem triggers breathing.
In those who live with NMD, a weak diaphragm does not move up and down well, and weak intercostal muscles do not expand the ribs well. And as the disease progresses, it becomes difficult to cough and to take deep breaths. Shallow breathing can provide the body with adequate oxygen supply and adequate removal of carbon dioxide. That delicate balance of O2 and CO2 allows breathing to continue. It is when extra or supplemental Oxygen is given while the individual has no assistance with air moving into and out of the lungs (is using no mechanical ventilation), that this balance can be disturbed. In the process, the respiratory center in the brainstem may get the false impression that the body has enough O2 and no longer needs to breathe. Without breathing, CO2 can build to dangerous levels (called hypercapnia) that can result in death.
Safe Administration of Supplemental Oxygen
There are ways of giving supplemental Oxygen and monitoring Carbon Dioxide safely. First, Oxygen should NEVER be given without constantly monitoring the level of Carbon Dioxide in the expired breath (the “end-tidal CO2”), which can be done by use of a device called a capnograph or by determining the CO2 level in blood which can be done by an Arterial Blood Gas (ABG) sample. A normal end tidal CO2 is between 30-45 mmHg. A CO2 level of more than 45 mmHg is too high and an indication that CO2 is not being expelled from the body. This causes Hemaglobin in the blood to become saturated with Oxygen that the blood takes to the body. If the Hemoglobin is tested and is found to not be saturated with Oxygen, that too can be an indication that there is too much CO2 in the body and that not enough Oxygen is getting into the blood. Non-invasive bi-level ventilation (i.e. BiPAP, BPAP, or portable ventilator) will assist with the mechanical process of breathing, delivery of O2, and removal of CO2.
Reference: http://community.parentprojectmd.org/profiles/blogs/oxygen-and-duchenne
Supporting References
Below, are documents that warn us of the danger of supplemental Oxygen. For more information, please consult a clinician who specialize in the breathing issues of those who live with NMD.
Diagnosis and management of Duchenne muscular dystrophy, part 2: implementation of multidisciplinary care
Katharine Bushby, Richard Finkel, David J Birnkrant, Laura E Case, Paula R Clemens, Linda Cripe, Ajay Kaul, Kathi Kinnett, Craig McDonald, Shree Pandya, James Poysky, Frederic Shapiro, Jean Tomezsko, Carolyn Constantin, for the DMD Care Considerations Working Group.
"Supplemental oxygen therapy should be used with caution because oxygen therapy can apparently improve hypoxemia while masking the underlying cause, such as atelectasis or hypoventilation. Oxygen therapy might impair central respiratory drive and exacerbate hypercapnia.91,95,103 If a patient has hypoxemia due to hypoventilation, retained respiratory secretions, and/or atelectasis, then manual and mechanically assisted cough and non-invasive ventilatory support are necessary.66 Substitution of these methods by oxygen therapy is dangerous.66"
See topic, "Respiratory Management" in the file available for download below.
There are many references warning about use of supplemental Oxygen (Oxygen given without use of assisted/mechanical ventilation) in individuals living with Neuromuscular Disease (NMD) who have weakened breathing muscles. Sadly, many individuals and some health care providers are not aware of this risk, and this can lead to significant worsening of the individual's symptoms. In extreme cases, it can cause death.
How can supplemental Oxygen be dangerous?
There are two parts of respiration: the mechanics of breathing and the exchange of Oxygen (O2) for Carbon Dioxide (CO2). When inhaling air, the diaphragm and intercostal muscles contract, the diaphragm moves down, and the ribs move up. This creates space within the chest, and air rushes in to fill this space (Oxygen). When the air rushes in, the air goes to the lungs where this Oxygen (O2) is exchanged for Carbon Dioxide (CO2). Oxygen then passes into the blood and travels into the hemoglobin to the cells. The muscles of the chest relax and the air, now filled with CO2, is pushed out of the body. Breathing happens automatically, and it is regulated by the respiratory center in the brainstem. When the body has too much CO2 or not enough O2, the brainstem triggers breathing.
In those who live with NMD, a weak diaphragm does not move up and down well, and weak intercostal muscles do not expand the ribs well. And as the disease progresses, it becomes difficult to cough and to take deep breaths. Shallow breathing can provide the body with adequate oxygen supply and adequate removal of carbon dioxide. That delicate balance of O2 and CO2 allows breathing to continue. It is when extra or supplemental Oxygen is given while the individual has no assistance with air moving into and out of the lungs (is using no mechanical ventilation), that this balance can be disturbed. In the process, the respiratory center in the brainstem may get the false impression that the body has enough O2 and no longer needs to breathe. Without breathing, CO2 can build to dangerous levels (called hypercapnia) that can result in death.
Safe Administration of Supplemental Oxygen
There are ways of giving supplemental Oxygen and monitoring Carbon Dioxide safely. First, Oxygen should NEVER be given without constantly monitoring the level of Carbon Dioxide in the expired breath (the “end-tidal CO2”), which can be done by use of a device called a capnograph or by determining the CO2 level in blood which can be done by an Arterial Blood Gas (ABG) sample. A normal end tidal CO2 is between 30-45 mmHg. A CO2 level of more than 45 mmHg is too high and an indication that CO2 is not being expelled from the body. This causes Hemaglobin in the blood to become saturated with Oxygen that the blood takes to the body. If the Hemoglobin is tested and is found to not be saturated with Oxygen, that too can be an indication that there is too much CO2 in the body and that not enough Oxygen is getting into the blood. Non-invasive bi-level ventilation (i.e. BiPAP, BPAP, or portable ventilator) will assist with the mechanical process of breathing, delivery of O2, and removal of CO2.
Reference: http://community.parentprojectmd.org/profiles/blogs/oxygen-and-duchenne
Supporting References
Below, are documents that warn us of the danger of supplemental Oxygen. For more information, please consult a clinician who specialize in the breathing issues of those who live with NMD.
Diagnosis and management of Duchenne muscular dystrophy, part 2: implementation of multidisciplinary care
Katharine Bushby, Richard Finkel, David J Birnkrant, Laura E Case, Paula R Clemens, Linda Cripe, Ajay Kaul, Kathi Kinnett, Craig McDonald, Shree Pandya, James Poysky, Frederic Shapiro, Jean Tomezsko, Carolyn Constantin, for the DMD Care Considerations Working Group.
"Supplemental oxygen therapy should be used with caution because oxygen therapy can apparently improve hypoxemia while masking the underlying cause, such as atelectasis or hypoventilation. Oxygen therapy might impair central respiratory drive and exacerbate hypercapnia.91,95,103 If a patient has hypoxemia due to hypoventilation, retained respiratory secretions, and/or atelectasis, then manual and mechanically assisted cough and non-invasive ventilatory support are necessary.66 Substitution of these methods by oxygen therapy is dangerous.66"
See topic, "Respiratory Management" in the file available for download below.
| diagnosis_and_management_of_duchenne_muscular_dystrophy_part_2.pdf |
Neuromuscular Disorders and Sleep in Critically Ill Patients.
Muna Muna Irfan, M.D., Bernardo Selim, M.D., Alejandro A. Rabinstein, M.D., and Erik K. St. Louis, M.D., M.S
“...oxygen should not be utilized without ventilatory support.” “...oxygen alone could further blunt the hypoxic drive to breathe, raising the risk for severe hypercapnia and respiratory failure.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5034932/ Page 3.
Going to the Emergency Room: Tips for People with Neuromuscular Diseases.
Donna Albrecht
"...individuals in respiratory distress may be given supplemental oxygen, even though their problem is not caused by lack of oxygen but by weak respiratory muscles. Too much unnecessary oxygen can cause a potentially life-threatening suppression of breathing." https://www.mda.org/quest/article/going-emergency-room-tips-people-neuromuscular-diseases
Muscular Dystrophy Canada's Guide to Respiratory Care for Neuromuscular Disorders
"In the general population, hypoxemia (low levels of oxygen in the blood) is commonly treated with supplemental oxygen. For people with neuromuscular disorders who are experiencing respiratory difficulty, however, oxygen therapy must be used with great caution. mechanical ventilation (preferably non-invasive) should be the initial therapy for people with neuromuscular disorders who experience hypoxemia.
If you are sent to the emergency department with respiratory complications, be prepared to communicate to the health-care team that you have a progressive neuromuscular disorder and that receiving supplemental oxygen without ventilatory assistance can worsen the situation.
There may be other confounding conditions (i.e. pneumonia) that necessitate the use of supplemental oxygen in addition to mechanical ventilation. The health-care team must be able to closely monitor your carbon dioxide levels (with a blood gas or transcutaneous monitor)."
See "Caution: Oxygen Therapy" at the bottom of page 18 in the file available for download below.
Muna Muna Irfan, M.D., Bernardo Selim, M.D., Alejandro A. Rabinstein, M.D., and Erik K. St. Louis, M.D., M.S
“...oxygen should not be utilized without ventilatory support.” “...oxygen alone could further blunt the hypoxic drive to breathe, raising the risk for severe hypercapnia and respiratory failure.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5034932/ Page 3.
Going to the Emergency Room: Tips for People with Neuromuscular Diseases.
Donna Albrecht
"...individuals in respiratory distress may be given supplemental oxygen, even though their problem is not caused by lack of oxygen but by weak respiratory muscles. Too much unnecessary oxygen can cause a potentially life-threatening suppression of breathing." https://www.mda.org/quest/article/going-emergency-room-tips-people-neuromuscular-diseases
Muscular Dystrophy Canada's Guide to Respiratory Care for Neuromuscular Disorders
"In the general population, hypoxemia (low levels of oxygen in the blood) is commonly treated with supplemental oxygen. For people with neuromuscular disorders who are experiencing respiratory difficulty, however, oxygen therapy must be used with great caution. mechanical ventilation (preferably non-invasive) should be the initial therapy for people with neuromuscular disorders who experience hypoxemia.
If you are sent to the emergency department with respiratory complications, be prepared to communicate to the health-care team that you have a progressive neuromuscular disorder and that receiving supplemental oxygen without ventilatory assistance can worsen the situation.
There may be other confounding conditions (i.e. pneumonia) that necessitate the use of supplemental oxygen in addition to mechanical ventilation. The health-care team must be able to closely monitor your carbon dioxide levels (with a blood gas or transcutaneous monitor)."
See "Caution: Oxygen Therapy" at the bottom of page 18 in the file available for download below.
| md_canada_guide_to_resp_care.pdf |
Quantitation of oxygen-induced hypercapnia in respiratory pump failure
Michael Chiou, John R. Bach, Lou R. Saporito, and Oluwasegun Albert
“For only 2 of 316 intubated patients were CO2 levels known to the clinician administering O2 and intubating the patient. Physicians need to obtain CO2 analyses before administering O2 to NMD patients with respiratory distress and to attempt to resolve the problem by using CNVS and MIE. The O2 should only be administered if CNVS and MIE have failed to normalize ambient air O2 sat, in which case they should be prepared to intubate. Whereas hypercapnic lung disease patients have poor prognoses with a 5-year survival of 30% for patients whose forced expiratory volume-one second (FEV1) is less than 750 mL,23 patients with NMD have been reported to have survived 20 to over 60 years using CNVS.20 Thus, O2 therapy should not be used as a substitute for NVS and MIE to maintain normal O2 sat (>94%). Avoiding O2 also permits oximetry to gauge hypercapnia, airway secretion encumbrance, and intrinsic lung disease as well as the effectiveness of NVS and MIE in treating them.24” https://www.sciencedirect.com/science/article/pii/S2173511516300057.
Michael Chiou, John R. Bach, Lou R. Saporito, and Oluwasegun Albert
“For only 2 of 316 intubated patients were CO2 levels known to the clinician administering O2 and intubating the patient. Physicians need to obtain CO2 analyses before administering O2 to NMD patients with respiratory distress and to attempt to resolve the problem by using CNVS and MIE. The O2 should only be administered if CNVS and MIE have failed to normalize ambient air O2 sat, in which case they should be prepared to intubate. Whereas hypercapnic lung disease patients have poor prognoses with a 5-year survival of 30% for patients whose forced expiratory volume-one second (FEV1) is less than 750 mL,23 patients with NMD have been reported to have survived 20 to over 60 years using CNVS.20 Thus, O2 therapy should not be used as a substitute for NVS and MIE to maintain normal O2 sat (>94%). Avoiding O2 also permits oximetry to gauge hypercapnia, airway secretion encumbrance, and intrinsic lung disease as well as the effectiveness of NVS and MIE in treating them.24” https://www.sciencedirect.com/science/article/pii/S2173511516300057.
Dr. John R. Bach "DO NOT administer supplemental O2 for sustained periods without CONSTANT monitoring of EtCO2 with a capnograph (monitoring device that measures the concentration of carbon dioxide). EtCO2>43 mmHg indicates CO2 retention. Administration of O2 can cause CO2 to rise, resulting in hypercapnia, coma, and DEATH!
Sustained hypercapnia (EtCO2>43) requires mechanical ventilatory assistance. Use noninvasive ventilation via mouthpiece or nasal interface with high-span Bi-PAP (typ. 18/2, rate 10) or volume vent (typ. 1000 ml, rate 10, command/assist mode). If unconcious, intubation may be required." http://www.doctorbach.com/er.htm
Oxygen is NOT for Hypoventilation in Neuromuscular Disease
E.A. Oppenheimer, MD, FCCP
It was originally published in the International Ventilator Users Network IVUN News, Spring 2000, Volume 14. See file available for download below.
Sustained hypercapnia (EtCO2>43) requires mechanical ventilatory assistance. Use noninvasive ventilation via mouthpiece or nasal interface with high-span Bi-PAP (typ. 18/2, rate 10) or volume vent (typ. 1000 ml, rate 10, command/assist mode). If unconcious, intubation may be required." http://www.doctorbach.com/er.htm
Oxygen is NOT for Hypoventilation in Neuromuscular Disease
E.A. Oppenheimer, MD, FCCP
It was originally published in the International Ventilator Users Network IVUN News, Spring 2000, Volume 14. See file available for download below.
| oxygen_is_not_for_hypoventilation_in_neuromuscular_disease.pdf |