Breathlessness – The Lack of Oxygen
Emergency medicine considers oxygen to be a drug used for patients with indications or risk of hypoxia (such as difficulty breathing, low SpO2 under 95%, and chest pain). EMT (Emergency Medical Technician) philosophy holds true to the belief that giving any patient oxygen is usually okay if you believe it would benefit them. One of the central pillars of breathlessness is inflammation, which partially blocks oxygen from getting into the cells.
With COPD patients, adequate air is brought into the alveoli, but the oxygen contained in the air is not able to pass into the capillaries surrounding the alveoli. This results in low oxygen levels and is called hypoxemia. Breathing even small amounts of additional oxygen helps when the oxygen level in the air rises above 21% to 23 or 24%. This small amount is enough to help “push” the oxygen into the capillaries but it is not near enough to put out the inflammation in the capillaries that is crippling oxygen transport into the tissues.
Since the body cannot store oxygen, oxygen needs to be given whenever the body is low on oxygen and for some people that has to be 24 hours a day. The need for continuous oxygen is called long-term oxygen therapy (LTOT).
Breathlessness is not thought to be a reliable way of determining the need for oxygen. Sometimes, you can be very short of breath and not need oxygen; other times your breathing may feel okay, but you are not getting enough oxygen.
The Royal Society of Medicine in England tells us that breathlessness, which is difficult, labored or uncomfortable breathing, or what is otherwise known as dyspnea—is a complex experience of the body and the mind. It is the most common and distressing symptom of advanced lung cancer and frequently affects those whose cancer originates outside the thorax.
Unlike cancer pain, breathlessness is difficult to treat successfully. Surveys of patients treated by a community palliative care teams demonstrate that the prevalence of breathlessness rises as death approaches. Although clinicians and patients alike tend to associate cancer with pain, breathlessness has a comparable incidence: in one recent study 85% of patients with cancer experienced pain and 78% experienced breathlessness in the last year of life.
Dyspnea is not simply an abnormality of the heart and lungs; it is a multisystem disorder with many accompanying subtle neuro-hormonal abnormalities and alterations in skeletal and respiratory muscle structure and function. The higher centers responsible for thinking and feeling can strongly influence the severity of the symptom. The ‘nervous system is not hard-wired’: it is characterized by plasticity and, just as with pain, the experience of breathlessness is likely to be modified both by previous experience of the sensation and by pathways from different areas in the central nervous system. Patients with apparently similar disease can have breathlessness of widely different severity.
Breathlessness is the subjective sensation of difficult, labored or uncomfortable breathing. Physiologically, we are all aware of breathlessness when we exercise beyond our normal tolerance but pathologically it can occur with little or no exertion.
Afferent sources for the sensation of breathlessness arise from receptors in the upper airway, lungs and chest wall as well as autonomic centers in the brain stem and motor cortex. It is almost always associated with fear and, when chronic, can be disabling and severely diminish quality of life.
In the Lancet we read, “Dyspnea is a subjective sensation that is frequently described by patients as fatigue upon breathing, air hunger, suffocation, choking or heavy breathing. The prevalence of severe dyspnea has been reported as 65%, 70% and 90% in terminally ill patients with heart failure, lung cancer and COPD, respectively. In the oncological population, dyspnea can be a direct effect of the cancer, an effect of the therapy, or not related to the cancer or therapy. In addition to cancer, patients may suffer from chronic obstructive pulmonary disease (COPD), congestive heart failure, non-malignant pleural effusion, pneumonitis, airflow obstruction, bronchospasm associated with asthma, and/or anxiety. Moreover, dyspnea may be a clinical expression of severe anemia, overwhelming cachexia and asthenia causing muscle weakness. Many different causes may co-exist in a patient.
The Australian Lung Foundations declares, “Oxygen is essential for life. In normal healthy people, the blood oxygen level is usually above 85 units (mmHg). In people with lung problems, this level may fall to quite low levels even though the body can continue to perform normally. If the oxygen level falls below 55-60 units, added oxygen may be helpful. Chronic obstructive pulmonary disease (COPD) is the term commonly used by doctors to describe the smoking-related conditions of emphysema and chronic bronchitis. Patients with these problems become severely short of breath, often with a normal oxygen level. In the later stages of COPD, however, low oxygen levels also become more common. In patients with severe COPD and low oxygen levels of 55-60 units or below, added oxygen prolongs life and in some cases also improves the quality of their life. Patients who use their added oxygen for 24 hours a day show a longer life span than those who use it for 15 hours; and these people, in turn, do better than those who use it only during sleeping hours.”
Oxygen is often contraindicated in patients with COPD because it is believed that these patients’ bodies use low oxygen levels to stimulate breathing rather than high carbon dioxide levels. EWOT (Exercise with Oxygen Therapy), which increases both CO2 and oxygen together, would be the safest way to help these patients. However, EMT professionals do not hesitate because of a history of COPD.
Giving high concentrations of oxygen to infants for long periods is believed to cause eye damage, but for average transport times in ambulances this is unlikely. The two commonly used devices for administering oxygen are masks and nasal cannulas, you can also include supplemental oxygen when using a bag valve mask. Masks are usually used for high concentration oxygen; textbook dosage is between 12 and 15 liters per minute. Nasal cannulas are normally used for low concentration oxygen, and the textbook dosage is between 4 and 6 liters per minute.
Anti-Inflammatory Oxygen Therapy pumps in as many liters a patient can breathe while they are on a far-infrared mat or exercising on a treadmill or exercise bike. For that, these masks and cannulas are worthless because they use a narrow tube from a limited oxygen source.