Some facts about COPD you should know

What you should be aware of

What is fact and what is fantasy in the world of CODP? There are several things patients need to be aware of when having discussions about their disease with their doctors. The chronicity, the obstruction, the treatable feature, the progression, and the prevention, has been outstanding topics in the literature for physicians. That without talking about the complications and other diseases frequently associated to this disease.

How and why it is chronic

The disease is chronic which means that it is not acute, it didn’t happen suddenly and is the result of a long time of progressive damage. With that said, we can’t not reverse it to normal as soon as we can start therapy. It’s awful to say that “damage is done” because is an over-simplification of the fact that damage can continue if we don’t take appropriate actions. What we can say is “It’s not too late” to start taking control of some domains of the disease. So, let’s be sure that we all understand that one medication, one exercise, one visit to the doctor will be enough. Let’s be sure that we understand that it started some time ago and it may take some other time to be under control.

What obstruction means

Obstruction is a kind of complicated. The reasons for this is because, in pulmonology, obstruction means any reduction in the caliber of the airway. We (the complicated-in-physiology pulmonologists) have one word that prefer not to use (occlusion) because it may imply that the airway is closed or blocked indefinitely. The latter can happen with some tumors in the space of the airways and can be an undesirable mess. Obstruction in COPD, however, is complex because the continuous contraction of the very muscles around the lung airways lead to strong/permanent contraction and it can be complicated with the excessive  mucus production of some patients (like long term asthmatics and chronic bronchitis). However, not all patients produce excessive mucus (which is associated to a particular type of inflammation) which leads us to think that the main therapy for COPD should be a long acting bronchodilator (airway muscle relaxant).

Worthy to treat

The disease has been shown to be treatable. Give that “some” of the mechanisms associated to obstruction in the airways has been described, several medicines and non-pharmacological interventions have shown to be of benefit reducing the bronchospasm (obstruction) as well as improving different outcomes related to this (like power to inhale, physical and social engagement, etc.). Even more, if the patient has stopped smoking the probability to get more control is outstanding.

Oh, no! … progressive

The progression shouldn’t make us feel scared. The disease is progressive, it’s true but aging is also progressive, hair loss is also progressive, skin wrinkling is also progressive, as well as some vision changes and it doesn’t mean that the worst will happen no matter what you try. Let’s face it: rehabilitation, medications, control of other factors may help in the delay of the progression although mathematical-scientific data can’t show it sometimes.

Prevent

Prevention definitely works because if you don’t smoke or are not exposed to the factors involved in the development of the disease, you don’t develop it. So, it is key to stop smoking, to avoid risk factors, to control associated diseases (e.g. asthma) to help the physician’s efforts to put you in your best shape.

So, don’t forget it: be realistic but not unnecessarily pessimistic. Help your doctor understanding where you are and getting more of their directions for coping in the best way with your disease.

From Smoking to COPD: what’s going on in the middle?

Doubtful association
It has been said that there is no a definite correlation between the spirometric standard FEV1 and the clinical manifestations in COPD. The FEV1 may be extremely low but the patient may be doing well. So where is the real assessment of the condition? Why COPD seems to be a big puzzle for doctors and patients?

Smoking and a show of symptoms
A long time ago smoking has been linked to development of serious health conditions. Symptoms have been associated with the smoking behavior but some say that it may not be any disease.

What is normal?
This is the most enigmatic perspective about a disease: symptoms being considered normal when we all know that smoking is not normal, coughing frequently with or without sputum is not normal, a development of exaggerated breathlessness with less extenuating efforts is not normal.

Some Learning

This is what teaches us that some times (if not every time) it is better to hear the patient, to assess them from a more clinical (humanitarian) perspective than relying in para-clinical procedures. Making diagnosis only based on technical methods may bring huge disastrous consequences. Particularly when it is expected to find changes in numbers more than in the body that can be assessed with appropriate developed strong skills. When it may be easy to evaluate a patient more physically than going into an algorhythm that may simplify the “clinical” decision making process but waiting for cold results. 

What to do to start?
Smoking cessation is fundamental based on clinical scientific data but we also know that symptoms associated to the continuous irritation of the airway don’t go away after smoking cessation.

Looking at the patient beyond the tech
Given these two considerations (smoking related symptoms and their persistence) we should look at the COPD patient as a real patient. It seems to be disregarding from the medical side that there is an abnormal condition due to COPD and maybe FEV1 will not be the best or definitive assessment to follow the disease up.

How to look at a COPD patient
Patients need to be considered more than a scientific set of individuals, a population to be seen from a statistical standpoint. Patients need to be seen individually and treated according to what has been shown in clinical trials but adjusted to the individual clinical reality.

History to be written
So… it is still required to look for a more clear and fair standard to monitor smoking and its effects. I hope that beyond FEV1 physicians are starting to take into account the sufferer.

COPD: Basic Steps to help

Just Dyspnea and It’s my fault

The COPD patient complains of breathlessness when cough and (sometimes) phlegm have been present for a longer period of time. Some experts have considered that when breathlessness is already installed there are chances for improvement. There are options and no space for regrets. Although the self blaming changes the perspective of some patients, physicians and other health care givers may reinforce the power of the patient.

Patients need to consider their own will since not all the control is on health system’s hands. So what a patient can do?

Understanding the basic: Chronicity

Patients with COPD must understand the chronicity of the disease. It’s not by coincidence that it occurs or develop. More than a lotto result is one of the potential reactions to continuous exposure to noxious particles and gases. Although this exposure happened a long time ago there is a trend in our organism to keep living and the immunological reactions continue. 

The risk factors

Smoking is a key risk factor and of course the most important. However, our current environments are polluted and there is some concentration of population in big cities or industrial areas where it’s easier to inhale low quality air. At the same time, there are some occupations that predispose to continuous inhalation of bad air.

Old “Normal” Symptoms

The COPD patient develops symptoms progressively. The progressive appearance of symptoms allows certain level of adaptation. Most of the patients consider their symptoms as normal and tend to accept them as natural until they become bothersome not only for them but for people around. It’s not the cough what bothers people as much as somebody breathing with difficulty continuously.

Education as basics

Considering the relevance of self education in the management of the disease, an appropriate interaction of the patient with themselves, and with information sources, care givers, health system, may help them to cope better with the disease. Some patients may prefer an academic source, while others tend to go to news or friendly scientific writers, but the important issue is to select a few that answer and help according to the individual needs.

It may be good to create regularity visiting some sources of getting information from certain books. However it is the patient who must choice to get the most of the current evolving knowledge on COPD.

Some considerations on self education

As general recommendations, given the constant flow of information, there are some basic things that COPD patients may do to help in their health support:

1. Understand the basics of the disease
2. Conceive it as chronic and progressive
3. Identify the cause and modify it
4. Precise a few sources of written information based on individual needs
5. Stick to the physician directions in terms of medication and office visits

In a next post let’s define more features that may help in the selection of written sources of COPD information.

COPD: Changing and not the Same for all Sufferers

Heterogeneous Disease

COPD has shown to be a heterogeneous disease. As with any other disease, there seems to be very unique and common features to help physicians in the diagnostic process as well as in therapeutic decisions. Long time ago, COPD was considered to be a syndrome based on a reaction to the continuous aggression by cigarette smoking imposed against the beautiful lung airway structure. Patients were considered to have one of two typical expressions of consequences: chronic bronchitis or emphysema.

Santa Klaus maybe had COPD (because of the chimneys?)

There are some patients with more features of chronic bronchitis but we never forget the classical emphysematous patient: skinny, always smoking, with their head among shoulders instead of above them, dry cough, etc, etc. In the meantime, the chronic bronchitis patient was fatter, smiling, coughing and producing sputum, and breathing with difficulty (just imagine Santa Klaus after he inhaled smoke while working…).

Question

The big question is: why some patients show one or other predominant characteristic of the disease? why ones are emphysematous while others have predominant chronic bronchitis?

Some help but different

That reminds us that categories help but are not definite. That reminds physicians that each patient is different to the other although key features may be common. Not all patients respond the same to cigarette smoking injure so they maybe don’t have to respond equally to same therapeutic measures. They even neither have the same behavior nor have the same attitude during the medical office dialogue. Understanding the actual or potential differences may help support a better approach to disease management.

More differences

So, will everybody have same adverse events? will they have same set of surrounding diseases? (which we call comorbidities). Maybe not and perhaps some may be followed up with spirometry, while others need to be followed up with activity levels, or breathlessness (dyspnea) scales, or symptoms exacerbations, or oxygen levels changes, just for mentioning a few couple of parameters.

Changing focus of investigations

These considerations, fortunately, have led some investigators to start talking about different phenotypes of COPD. Although it challenges our current understanding of the disease, already considered complex and under continuous evaluation to make it look simpler, patients and multiple clinical trials have been shown that the damage is not as homogeneous as we could have thought in the population.

Similarities

We also know that in metabolic diseases some patients present different complications (e.g. diabetics with more renal impairment than neuropathy). In hypertension, some have stroke while other have heart predominant damage. They all have different medical approaches and require different directions: some need to loss weigh, others have to change diet, others respond to a drug better than others, etc.

A Disease in evolution

COPD is starting its own cycle of research, adjustment according to the evidence, natural evolution of the crowd of patients, new and contradictory trends in management, followed by more research and so forth. The present is here and now and the hope is increasing thanks to the investigators who have given passion to this issue. Each patient is different because, simply: individuals are not the same.

Patients with earlier COPD: appropriate attention?

Patients less severe?

According to the Global Initiative for Obstructive Lung Disease (GOLD), there are patients con COPD with minimal changes in the standard method for diagnosis: spirometry.

Spirometry is the only way a doctor can tell a patient if they have COPD and how severe it is. The Forced Expiratory Volume in the first second (FEV₁) helps in the classification of severity. The maximal amount of air exhaled after 6 seconds in a forced maneuver in called Forced Vital Capacity (FVC) and when the FEV₁ is less than 70% of FVC the obstruction in the airway is considered to be present.

Relevance of even early Spirometry 

Obtaining these values is really helpful. The goal to get the factual numbers i to be in the best status of open airways. That’s the reason why patients are asked to inhale a bronchodilator (rescue inhaler) and then they perform the spirometry. The numbers obtained are called post-bronchodilator FEV₁ and FVC.

Interestingly, FEV₁ needs to be compared to the predicted value according to other demographic variables like gender, height, weight, etc. If the FEV₁ is more than 70% of the predicted value, patients are considered to have mild COPD even with an FEV₁/FVC ratio less than 70%.

Guidelines and Early COPD

GOLD guidelines recommend rescue inhalers for these cases. Some doctors wonder if we could do the same with mild hypertension (management of crisis only) knowing that the disease is there anyway. There are some other measures to be taken for mild COPD patients like avoiding risk factors (smoking), annual vaccinations, changes in lifestyle and, I would say, continuous education.

Anything to do for less advanced COPD?

COPD is a progressive disease that need to be treated anyway. If we all know that it leads to an accelerated loss of lung function, which means a more rapid decrease of FEV₁ each year, it may be advisable to start looking at the disease seriously since its diagnosis.

Symptoms vs. Spirometry

Spirometry is a key indicator for the presence and severity of the disease but some symptoms may remind patients and physicians that something is not working appropriately in the lungs earlier. The presence of cough and some sputum production, breathlessness with some activities in the frame of fumes, dust, or any continuous noxious gas exposure should alert about COPD.

Looking for Patients’ Health Benefits

The good news is that we know more and more about the disease each year. There are more patients in earlier stages of the disease who are not receiving any medical intervention (including education). An engagement into the reality of the progressive nature of the disease may help to have a better quality of life when we all know that something can be done. Think about the quality of care all patients need and how they could get more benefits of life and health just understanding a little bit more of their disease.

Pucker for a better breathing: Pursed Lip Breathing

Natural Adoptions

Patients with advanced COPD look for a more complete exhalation leading to more room for breathing. That’s the reason why they breath out slowly and their lips pursed. This technique, naturally adopted by advanced COPD patients, can also be adopted by less severe COPD patients to take more of the benefits of better breathing.

The cause for Pursed Lip Breathing

When the lung airways are obstructed due to brochoconstriction (contraction of smooth muscles bands wrapping the airway), the air is trapped inside the lungs and leads to less area for exchange of oxygen to the blood. As a result patients require more time to exhale that trapped air; making lung areas available for gas exchange.

Extending the airway and keeping it open

What represents the patient’s intention to pucker their lips is the extension of the airway at the mouth level. Now the air has more way to run and this requires time, prolonging the exhalation. It also maintain the airways open during more time. The sensation for the patient is more comfortable than shortening the airway.

Pursed Lip Breathing in the Healthy

The interesting issue of this natural defense against air trapping is that healthy people do it when exhausted or during exercise workouts. It allows a better timing for using the benefit of breathing.

It has been recommended to practice the technique at least 5 minutes every day to become familiar with it. It doesn’t have to be preceded by a deep-deep breath in but by a normal inspiration. It may be practiced early morning or before going to bed (also making of it a moment of relaxation and/or meditation).

What to do?

Seated or in standing position, the patient should look ahead and relax the neck. This is followed by a normal inspiration (breath in) through the nose (closed mouth). Pucker the lips and start the breath out (through the mouth) as if the intention was to whistle. Take your time until you feel you don’t need to exhale more room. Start again. Remember: no deep breath or it may lead to dizziness.

The benefit

COPD patients have the feeling of wellness after practicing the “pursed lip breathing” technique. That’s what we all are looking for. Our patients require some time to be instructed about the benefits of this breathing technique (it’s not a pure breathing exercise). It helps patient and put into practice principles of physics and physiology in the lung ventilation. Talking to patients about it may make a huge difference in the office conversation also.

Airflow Obstruction vs. Air Trapping in COPD

Only obstructive?

Since long time ago, COPD has been considered an obstructive disease (its name says it clearly). Of course, there is obstruction in the lung airways as a result of persistent bronchospasm. However, an effect of the obstruction has been studied recently and has been associated to the symptoms more than the obstructive component itself.

More than obstruction: air trapping

The obstruction of lung airways leads to air trapping in the distant units. These units, called alveoli, are the areas where gas exchange occurs as well as the pulmonary blood circulation has place. When the air gets trapped inside them both processes occur slower than expected and symptoms appear.

Dyspnea, the most bothering symptom for patients, has been associated to the levels of air trapped more than obstruction. Airflow obstruction has been found to represent the severity of the disease but air trapping is a consequence that leads to increased local pressure and physiological changes reflected in exercise intolerance.

A recent article

In his recent “Update in the Management of COPD” (Chest 2008;133:1451-1462), Dr. Bartolome R. Celli points out the relevance of air trapping in the manifestations of symptoms independent of airflow obstruction. The fact that COPD is a multicomponent disease help us understand that management should be addressed to relieve all the manifestations possible and the management of dyspnea should be kept in mind when considering decisions.

Although Dr. Celli says that lung excess inflation is key in the genesis of symptoms in advanced disease, the importance of this physiologic hallmark has not been assessed in early stages. Two main factor may be defining this issue: the lungs’ elasticity and the symptoms minimization by patients.

Air trapping during physical activities

The concept of air trapping in COPD is more impacting during exercise or any other physical activity. When oxygen demand increase, the exhalation can not happen smoothly and air gets trapped in lungs. Unless the patient stop the activity, the excess inflation will limit normal breathing (particularly gas exchange and blood circulation in the lungs).

Not under the microscopy

Severe patients with emphysema may have their symptoms more severe due to those facts. These patients have the trend to develop considerable bubbles called bullae that take out space from the functional lung. This may be the macroscopical evidence of air trapping relevance, but it’s not necessary to wait until there.

How to find out if there’s air trapping

The true of the matter is asking for breathlessness to patients when they are smokers, when they already have cough and sputum production, when they say “I have smoker’s cough only“, is paramount to help them and take decisions. How much the activity is limited because of some “Tiredness” or “Fatigue” needs to be carefully assessed to find the results of air trapping in the elastic lungs. Masking symptoms is not good, in any case. Let’s assume the importance of the underlying air trapping (and lung excess inflation or hyperinflation).

Percussion of the Thorax during physical exam: some comments

An empty thorax?

Percussion of the thorax is a maneuver used by physicians to assess part of the integrity of lungs: their emptiness. As the lungs should be filled with air enough to be ventilated and proceed with the local gas exchange.

Lungs are like a huge sponge with a big difference from the typical ones: their dividing walls are full of blood and their spaces are full of air. The amount of air inside lungs is a big one: around 5 liters. Imagine 5 bottles of 1 liter each one inside the thorax and containing only air.

Just touching with two fingers

When percussion is performed hitting the tip of one middle finger on dorsal side of last joint in the other middle finger there is no special sound but some dullness. However, if the second finger is put over the thorax (not in the cardiac area) the sound is like the one on an empty box, similar to a drum, or the body of a guitar.

Some lung divisions

Lungs are composed by lobules (like having more than 2 sponges together). The right lung has 3 sponges together and the left has 2 and small one to give some space to the heart. The right has a big almost pyramidal that goes from the base of the thorax toward the whole back. Over its front there are the two other lobules: one bottom and other top. Here it was described right lung’s lobules: lower, middle, and upper.

For the purpose of this explanation, let’s avoid the left lung description.

Sonority vs dullness

The percussion of the thorax is normally sonorous (resonant). However, it’s not like an empty stomach but with some muffling (due to local blood circulation).

Some variety may be heard according to individuals. The resonance may be softer in an obese person than in the skinny. The expert will find normal sonority in each normal patient.

Changes in the back of right side of the thorax implies changes in the right lower lobe. In the front but bottom, percussion explores middle lobe while in the top front, it talks about upper right lobe.

Obvious changes of percussion in COPD

In COPD, the trapped air tend to increase the sonority of the thorax. It also happens in the symptomatic asthmatic as well as in other different circumstances. However, percussion of thorax is made with the purpose of looking for dullness like in pneumonia (when areas of the lung are filled with pus), pleural effusion (when the space between lung and rib cage is filled with more liquid that necessary to allow the breathing movement).

Granularities of COPD percussion

When a COPD patient has more emphysema than chronic bronchitis, the sonority by percussion is increased. It is also increased when the emphysema has led to creation of big bubbles called bullae. Its localized pattern may lead to clues about the severity of emphysema in precise areas.

A fact on percussion of the thorax

Percussion is a very helpful maneuver during physical exam of symptomatic respiratory patients. It completes the auscultation when it is abnormal. Not all patients will be explored with percussion but some of them may require this type of assessment when it’s necessary to confirm the excess presence of air, or a condition associated with dullness.

Don’t expect your general practitioner to do percussion in a routine manner. It’s just a confirmatory maneuver.

Patient-Physician communication addressing a physical exam

At the medical office there’s a need of a dialogue.

Dialogue between patient and physician

The dialogue between patient and health care provider should be based on the potential expectations of the patients, the level of knowledge, the individual variables, the respect for the patient time, and a consideration of the power of the patient. The respiratory patient usually bases his or her visit in on the interference with the ventilation of the lungs as well as new symptoms. All this information can be gotten through the appropriate partnership built in a few amount of time. However, it is more than time what defines an adequate approach during the assessment of a respiratory patient. It’s related to straight and high quality communication.

Communication: the big deal

In the construction of a patient-physician relation, the communication needs to overlap several processes to make of them a continuum. Sending is a key element in the messaging of information to a patient. But sending is not an exclusive process, the process of delivering information to a patient requires to expect a feedback, a series of immediate reactions. The reactions of the patient come to the physician in different ways, words, facial expression, gestures, silence. It’s responsibility of the physician to give value to the patient’s reaction and preparing more support. This specific details make of the typical sender a formal receiver, while the patient is a sender.

As always, our major feature as human beings is our main problem most of the times: verbal communication. This indicates a necessity of being constantly careful when talking to the patient or the physician. I my physician clear about what I do feel? Is my patient getting the right message? If no: why?

Fundamentals of diagnosis and treatment

An appropriate diagnosis is pending on precise information and adequate analysis. If a patient gives clear messages, the physician organizes a better approach. If a physician provides with clear definite recommendations and well designed instructions, a patient is put in the right track.

Part of the communicative procedure is also supported by a physical contact integrated to the conversation. It’s more than writing on the laptop while hearing answers to those cold medical questions. A close appropriate contact with the patient during the physical examination is not only the auscultation of the thorax but asking questions and hearing the patient.

Physical exam abridging the path to diagnosis

The physical examination is mostly oriented by the answers to specific questions. Is you mass sensation at the right side? implies a careful examination of the left and later of the right side. Is the pain more intense on the back or in the chest? Imposes a starting at the less painful location. All this to create a parameter for comparison.

Of course, the intention wouldn’t be to tell to the examiner what to do but how to do it. The examiner will make a general evaluation, but this will be followed by a confirmatory process to grade the level of symptoms impact on physical structures.

The indispensable patient voice

One thing is clear: what patient says is key for exact diagnosis and efficacious treatment. Then, in first visits, the physical exam should be a good complete one. The following exams should be directed to the abnormalities informed by the patient during the visit. This does not preclude an exclusion of complete exam if it is performed very infrequently.

Then, it seems to be clear that the skills of a physician need to be put into practice combining the information coming from the patient as well as knowledge and respect. If some of this elements are not working, the decisions are far from being well oriented.

Call to a synchronic action

Patients should prepare their conversation with doctors. Doctors should be prepared to hear patients and share with them the knowledge to improve the results of an office’s visit. This will lead to a smooth process of understanding of the parties programming the cure or the approach to handle the health condition.

 

Oxygen as a drug in some respiratory diseases

Oxygen is a key element for our body to work properly. All the effort of breathing is made to keep the levels of this gas in the appropriate range. The healthy human being does not realize of the physical breathing process as a routine when the entire body is working in the positive balance of oxygen taking. However a challenge to the environment is accompanied by an increase need in oxygen so our muscles can work for running away, jumping, cycling, climbing stairs quickly, making strides, etc.

Oxygen as a excess requirement

Respiratory ill patients like those with pulmonary fibrosis, chronic obstructive disease and asthma, pneumonia, rib fractures, etc. have a diminished surface to exchange oxygen and CO2 with the atmosphere. Although the surface for exchange may be big enough to favor CO2 release, some times oxygen will not find sufficient permeable tissue to get into the blood. That’s the reason why some patients must need supplemental oxygen and others may have a delayed requirement.

Lower level of activities acting as indicators

The respiratory imposed condition may not wait for for typical exhausting tasks to add symptoms or make the reduced level of oxygen more diminished. These diseases may make the oxygen need more apparent when getting up, walking, carrying a bag with groceries, or taking a shower. For some patients, just lying on bed may reduce the surface for exchange due to obesity, diafragm weakness, occlusive upper airway (as in sleep apnea/hypopnea) or enlarged heart (just some examples).

Basement of Oxygen prescription

To indicate oxygen therapy, physicians base their decision on objective oxygen measurement that may be non-invasive or invasive. The non-invasive procedure is the Pulse Oxymetry that assesses only oxygen through the skin. The invasive procedure implies a blood sample taken from an peripheral artery (with blood coming from the heart after taking oxygen from the lungs). With the measurement of Gases of Arterial Blood it comes also the levels of CO2, as well as HCO3, and pH (among other values).

Once the reduced arterial blood oxygen level is confirmed low (hypoxemia), the election is made. Of course the supplemental oxygen is not administered to correct hypoxemia only. The oxygen therapy is started to decrease the intensity of symptoms and to reduce the workload imposed to the cardiopulmonary system when it is trying to get its best for maintaining oxygen in the best range.

Oxygen Therapy Precautions 

The oxygen therapy has potential complications although it is clearly indicated. It needs to be re-assessed on a regular basis to avoid the complications. When the right level is reached re-assessments are less frequent.

One of the most feared complications of oxygen therapy is depression of ventilatory centers (chemically confused due to the new excessive amount of oxygen supplied). Unfortunately it may appear in patients with more requirement of oxygen like those with elevated CO2 levels. This tends to appear in the most serious cases of hypoxemia: advanced stages of COPD, severe persistent asthma, obstructive sleep apnea.

When the inspired fraction of oxygen is increased over the normal atmospherical level, there’s a described risk of atelectasis (colapse of lung units where the oxygen is taken). Other risk is oxygen toxicity.

Oxygen Toxicity: special chapter

Oxygen toxicity occurs due to its chemical effect on a cellular level. This excessive oxidation leads to death of cells where the impact occurs. Actually, this effect is correlated with time of exposure and what happens is an inflammatory reaction. First with the irritating action may appear the inflammation of the trachea and bronchi with middle chest pain. Then it may be followed by reduced lung space for exchange, rigidity of local tissues, altered balance of oxygen between air and blood, hypoxemia during exercise, and reduced diffusing capacity of gases that leads to CO2 retention and no oxygen is taken.

All this occurs while the injure is being established with lession of capillaries, swelling of the lungs, and cellular destruction.

Amount and Time

As the levels and time of continuous exposure represent a risky situation, the prescription of oxygen is regulated in terms of Liters of Oxygen and hours of exposure. This needs to be clearly communicated to patients with oxygen therapy and care givers to avoid toxicity and imbalance in blood gases that may lead to confusion at respiratory centers, for instance in the Central Nervous System, with CO2 retention and worsening hypoxemia.

Oxygen may be considered a drug as it has been described with biological effects and benefits as well as potential adverse effects and events that imply warnings and precautions.

Long term Oxygen Therapy in COPD

Patients with COPD have necessary long term supplemental oxygen indicated when they have severe COPD and arterial oxygen levels less than 7.3 kPa (55 mm Hg) with or without CO2 retention or if they have arterial oxygen levels in the range of 7.3 kPa to 8 kPa (60 mm Hg) with evidence of pulmonary arterial hypertension or peripheral edema (swelling) and increased red blood cells (also called erithrocytosis, erithrocythemia more appropriately, or polycithemia) as an exaggerated response to chronic reduced arterial oxygen.

A summary

In summary, respiratory conditions may reduce the oxygen in the circulating blood. This implies that some patients may require supplemental oxygen administration. In those patients, oxygen may be required for better performance of a wide range of physical tasks. Oxygen may be injuring if given in high amounts and for extended periods of time. The administration may be required for short or long periods of time and is based on body levels of oxygen.

Previous steps?

This may be a reason to think more about Pulmonary Rehabilitation when considering to adapt to some chronic respiratory conditions.