Protein in raw mild may prevent asthma/allergies

Reuters reports on a new study that shows that children who drink raw milk were less likely to get asthma as compared to children who drank pasteurized mild.   The theory is that certain proteins destroyed during the pasteurization process are useful in helping the immune system stay strong and fit.

Reuters quotes one experts as saying this may present scientists with a double edged sword.  While pasteurization kills unwanted bacteria from mild, it may also kill necessary proteins we need.

Another reason that pasteurized mild might do is prevent infants from getting exposure to certain bacteria necessary for a proper immune maturation process.  The Hygiene hypothesis states that infants not exposed to certain bacteria may develop asthma.  This study may be added proof of this hypothesis.

While raw milk tastes down right terrible in my humble opinion, many people believe pasteurization is not needed and raw milk has many health benefits, such as preventing asthma and allergies.

While further studies will be needed, this study may be further proof that the modern Western world is causing asthma.  Other theories suggest our modern diet, genes, pollution, Tylenol, c-sections, lack of breast feeding, premature birth, among others may have a negative impact on the immune system that results in lung inflammation that results in asthma and allergies.

Facebook
Twitter

read more...

Breathalizer may soon be used to diagnose lung diseases

A Breathalyzer to diagnose asthma.  This sounds futuristic, yet it might be an option for doctors in the near future.  If a doctor suspects asthma you just blow into the Breathalyzer and the device will give give an instant diagnosis.  Sounds pretty cool, hey?

The New York times reports that such a device is currently in the experimental stage.  The idea is that each disease of the lungs gives off certain chemical markers that are exhaled.  Such markers will allow doctor to easily diagnose asthma, tuberculosis, liver disease, cancer and other such diseases. 

The article quotes Dr. Raed Dweik, director of the pulmonary vascular program at the Cleveland Clinic, who studies breath analysis:  "Breath is a rich matrix that can reflect our state of health or disease." 

The Times reports that the device is called breathlink, and "Its analyzers can detect compounds in the breath in concentrations of parts per trillion — a billion times more sensitive than breath analyzers used by the police to detect blood-alcohol concentrations."

"To use Breathlink," the article continues, " a person breathes into a long tube, and a breath sample is collected and analyzed within the apparatus. The device can then detail chemical concentrations of the breath in graphics. The information is then collected and sent to a lab in New Jersey for further analysis.

Because Medicare has refuses to reimburse for the procedure, and for this reason it's not a common practice.  Just by the description it seems like a rather expensive procedure, and one that might not even be worth it.  Yet I can see how it might come to be useful in the future, once the bugs are worked out, and once it becomes a more convenient and less expensive procedure.

A similar device is currently used by some facilities to measure the amount of exhaled nitric oxide, which can be a marker of airway inflammation.  By using the device doctors can adjust medicine until inflammation in the lungs is controlled. 

Yet even this procedure doesn't come without some criticism. Studies are mixed as to the benefit of nitric oxide measurements in adjusting asthma medicine.  Likewise I imagine it will be a while before the Breathalyzer system will be perfected and is used as a common practice to diagnose diseases in the doctors office or in hospitals.

To diagnose asthma the breathalyzers will measure the markers of exhaled markers of inflammation, such as histamine and leukotriene.  

Another device is portable and once you exhale into it "he "breath is drawn across sensors that change color and are then captured on digital cameras. The patterns are then compared with those of people without the disease."

The goal is to not just be able to diagnose diseases but to allow patients and doctors to monitor whether the disease is improving or progressing. 

So this is some interesting research we'll continue to keep an eye on here at the RT Cave.  If you guys are aware of any similar information, or if you've used one of these devices, let us know in the comments below.

Facebook
Twitter Facebook
Twitter

read more...

School kids need quick access to rescue medicine

Think about this.  There are many asthmatic adults who are embarrassed or too modest to seek medical attention.  Many are even so modest that they prefer to use their rescue medicine in private.  So why would this be any different with children.

The truth is -- and this only makes sense -- that children are even more likely to not want to seek out help when they're having trouble breathing, let alone want to use their inhaler in front of someone.  And it's for this reason alone that school policies that ban kids from carrying their own inhalers are ridiculous.

The main concern of schools is that kids will abuse the medicine.  Yet the facts show that when an asthmatic kid needs his rescue medicine, he needs it prompt.  If he hesitates to seek out help, and it then takes a while to gain access to the rescue inhaler, this can result in worsening asthma and even death.

The fact is that kids need rapid access to their inhalers.  They shouldn't have to stress about how they are going to gain access to it, it should be right in their own little pockets.  If they want to grab it and hide around a corner to use it, then they should be allowed to do that.

I know for a fact when I was a kid I hated the other kids to see me using my inhaler.  I also hated them to see I was having trouble breathing.  So when I needed it I hid around a corner and took my puffs.  I was a shy kid, so seeking out adult help wasn't an option and probably never would have happened.

Many schools with "no medicine in kid pockets" policies are learning the hard way that these policies may not always be such a good thing.  It's sometimes better to risk kids abusing their rescue medicine than it is for those kids to suffer or die.

Likewise, it should be noted here that using your rescue inhaler when you are short of breath is not abusing it.  I think that some people assume -- especially those who don't have asthma -- that if a child uses his inhaler more than the doctor recommends that this constitutes abuse.  Yet that's not true at all.

Surely overuse of an inhaler can be a sign of worsening asthma and prompt medical attention is necessary.  Yet it can also be a sign of hardluck asthma, or asthma that is not well controlled with common asthma preventative medicines.

Perhaps with this wisdom in mind as many school policies -- like this one -- are being changed to the way it was when I was a kid where asthmatic kids can carry their inhalers and have quick access to them when they need them.

Sure kids should be educated.  Parents should be educated.  And even more important, teachers and any person who will be responsible for that child at school -- including janitors, cooks, and aides --- must be educated about asthma.  They must know who has it, what signs to look for, what to do if the signs are observed, what that kid's asthma triggers are, etc., etc., etc.

To be honest, when I was a kid, if a school had such a policy, I would have ignored it.  Not that I would be trying to be a rebel, but one size fits all school policies that don't consider the different personalities and needs of asthma students are bogus.  Asthmatic kids need to carry their own inhalers.  Period.

Facebook
Twitter

read more...

School kids need quick access to rescue medicine

Think about this.  There are many asthmatic adults who are embarrassed or too modest to seek medical attention.  Many are even so modest that they prefer to use their rescue medicine in private.  So why would this be any different with children.

The truth is -- and this only makes sense -- that children are even more likely to not want to seek out help when they're having trouble breathing, let alone want to use their inhaler in front of someone.  And it's for this reason alone that school policies that ban kids from carrying their own inhalers are ridiculous.

The main concern of schools is that kids will abuse the medicine.  Yet the facts show that when an asthmatic kid needs his rescue medicine, he needs it prompt.  If he hesitates to seek out help, and it then takes a while to gain access to the rescue inhaler, this can result in worsening asthma and even death.

The fact is that kids need rapid access to their inhalers.  They shouldn't have to stress about how they are going to gain access to it, it should be right in their own little pockets.  If they want to grab it and hide around a corner to use it, then they should be allowed to do that.

I know for a fact when I was a kid I hated the other kids to see me using my inhaler.  I also hated them to see I was having trouble breathing.  So when I needed it I hid around a corner and took my puffs.  I was a shy kid, so seeking out adult help wasn't an option and probably never would have happened.

Many schools with "no medicine in kid pockets" policies are learning the hard way that these policies may not always be such a good thing.  It's sometimes better to risk kids abusing their rescue medicine than it is for those kids to suffer or die.

Likewise, it should be noted here that using your rescue inhaler when you are short of breath is not abusing it.  I think that some people assume -- especially those who don't have asthma -- that if a child uses his inhaler more than the doctor recommends that this constitutes abuse.  Yet that's not true at all.

Surely overuse of an inhaler can be a sign of worsening asthma and prompt medical attention is necessary.  Yet it can also be a sign of hardluck asthma, or asthma that is not well controlled with common asthma preventative medicines.

Perhaps with this wisdom in mind as many school policies -- like this one -- are being changed to the way it was when I was a kid where asthmatic kids can carry their inhalers and have quick access to them when they need them.

Sure kids should be educated.  Parents should be educated.  And even more important, teachers and any person who will be responsible for that child at school -- including janitors, cooks, and aides --- must be educated about asthma.  They must know who has it, what signs to look for, what to do if the signs are observed, what that kid's asthma triggers are, etc., etc., etc.

To be honest, when I was a kid, if a school had such a policy, I would have ignored it.  Not that I would be trying to be a rebel, but one size fits all school policies that don't consider the different personalities and needs of asthma students are bogus.  Asthmatic kids need to carry their own inhalers.  Period.

Facebook
Twitter

read more...

Nasal congestion linked to severe asthma

Of course we've known for quite some time that nasal congestion can be an asthma trigger, yet a new study shows that nasal congestion may also be the main culprit when it comes to severe asthma.

The journal of Respiratory Research, and reported here at RTmagazine.com, was the first to publish the findings of a study done in Sweden. The results are significant because it's the first to estimate the "prevalence" of asthma in a given population. In Sweden, the number of Severe Asthmatics is estimated to be about 2 percent.

Nasal symptoms may be sinusitis, rhinitis (hay fever), runny nose and colds are all linked to causing nasal congestion. This is significant to asthma because sinus drainage makes its way to the lungs and triggers asthma.

The study author noted these results are significant because, "effective treatment for troublesome nasal and sinus complaints could, in theory, reduce the risk of severe asthma, though this is something that needs further research... and this may lead to new forms of treatment in the long run."

I think scientists have already been working on medicines to help with nasal congestion. Perhaps this might be an incentive to speed up research in this area.

Facebook
Twitter

read more...

Nasal congestion linked to severe asthma

Of course we've known for quite some time that nasal congestion can be an asthma trigger, yet a new study shows that nasal congestion may also be the main culprit when it comes to severe asthma.

The journal of Respiratory Research, and reported here at RTmagazine.com, was the first to publish the findings of a study done in Sweden. The results are significant because it's the first to estimate the "prevalence" of asthma in a given population. In Sweden, the number of Severe Asthmatics is estimated to be about 2 percent.

Nasal symptoms may be sinusitis, rhinitis (hay fever), runny nose and colds are all linked to causing nasal congestion. This is significant to asthma because sinus drainage makes its way to the lungs and triggers asthma.

The study author noted these results are significant because, "effective treatment for troublesome nasal and sinus complaints could, in theory, reduce the risk of severe asthma, though this is something that needs further research... and this may lead to new forms of treatment in the long run."

I think scientists have already been working on medicines to help with nasal congestion. Perhaps this might be an incentive to speed up research in this area.

Facebook
Twitter

read more...

A breeze proven to help with dyspnea

We observed here at the RT cave long ago that patients with lung diseases are often found with the windows open and/ or a fan on in the room blowing cool air.  A new study might prove that these patients might be on to a good method of decreasing dyspnea (air hunger).

I remember as a kid sticking my head out the window of my bedroom to get some relief from dyspnea.  Later I started using a fan in my room.  When I became an RT I observed that I wasn't the lone asthmatic to create a breeze in this way, as I observed many lungers in one way or another create a breeze in their rooms.

The February isue of RT Magazine had an interesting article, "Relieving Terminal Dyspnea:  Oxygen or Air," where a study done in 1993 by Bruera et al and published in Lancet  that compared giving 2lpm continuously of oxygen to some patients and air to others to see if oen or the other it did anything to relieve dyspnea.

Without knowing which patients were given what, all the patients observed that their dyspnea had improved regardless of whether or not they were given air or oxygen. In fact, patients in both groups noted an 87% improvement in perceived dyspnea after three days.

This study is significant because while the patients in the study noted dyspnea, none was hypoxemic.  Experts surmise from this what we have previously suspected, that a breeze reduces the feeling of dyspnea. This cool can be accomplished by:

• A fan blowing cool air
• A breeze from an open window (although this increases the risk of inhaling air pollutants)
• Gas flow in the nasal passages

Facebook Twitter

read more...

Once-a-day asthma medicine may soon be a reality

I've written often on my blogs how asthmatics yearn for a once-a-day asthma medicine.  While not approved for asthma, Indacaterol (Novartis) is a long acting beta adrenergic similar to salmetorol (Serevent) that has been approved for use by COPD patients in Europe.

A recent study published at Pubmed.gov concluded that "Once-daily treatment with 150 μg indacaterol had a significant and clinically relevant bronchodilator effect over 24 h post-dose and improved health status and dyspnoea to a greater extent than twice-daily 50 μg salmeterol. Indacaterol should prove a useful additional treatment for patients with COPD."

I think one of the main advantages of such a medicine is that it would greatly improve compliance with the medicine, making it much more likely the patient will actually take his medicines.  You just wake up, take your one puff, and your done for the day.  No more thinking about your asthma medicines.

Asthma experts have determined that if an asthmatic requries a long acting beta adrenergic like Serevent or Novartis the patient should also be on an inhaled corticosteroid to control inflammation. These meds would then work together to control asthma.

So while Novartis and Serevent might work well to improve lung function in COPD patients, they are not recommended as a top line treatment for asthma. 

However, this new medicine gives us hope that some day soon such a once-a-day medicine might soon be available, if an inhaled corticosteroid can be manufactured that lasts 24 hours.  A combination inhaler with both these meds might be gold for us asthmatics. 

Now it's also important to note that Novartis has not been approved for sale in the U.S.  I find that the FDA is quite a bit stricter releasing medicines to the U.S. market than other countries.  Yet soon this might be an option for American COPD patients as well as those in Europe.

And hopefully soon we asthmatics will have our once-a-day asthma medicine. Let's keep our fingers crossed.

Facebook
Twitter

read more...

Once-a-day asthma medicine may soon be a reality

I've written often on my blogs how asthmatics yearn for a once-a-day asthma medicine.  While not approved for asthma, Indacaterol (Novartis) is a long acting beta adrenergic similar to salmetorol (Serevent) that has been approved for use by COPD patients in Europe.

A recent study published at Pubmed.gov concluded that "Once-daily treatment with 150 μg indacaterol had a significant and clinically relevant bronchodilator effect over 24 h post-dose and improved health status and dyspnoea to a greater extent than twice-daily 50 μg salmeterol. Indacaterol should prove a useful additional treatment for patients with COPD."

I think one of the main advantages of such a medicine is that it would greatly improve compliance with the medicine, making it much more likely the patient will actually take his medicines.  You just wake up, take your one puff, and your done for the day.  No more thinking about your asthma medicines.

Asthma experts have determined that if an asthmatic requries a long acting beta adrenergic like Serevent or Novartis the patient should also be on an inhaled corticosteroid to control inflammation. These meds would then work together to control asthma.

So while Novartis and Serevent might work well to improve lung function in COPD patients, they are not recommended as a top line treatment for asthma. 

However, this new medicine gives us hope that some day soon such a once-a-day medicine might soon be available, if an inhaled corticosteroid can be manufactured that lasts 24 hours.  A combination inhaler with both these meds might be gold for us asthmatics. 

Now it's also important to note that Novartis has not been approved for sale in the U.S.  I find that the FDA is quite a bit stricter releasing medicines to the U.S. market than other countries.  Yet soon this might be an option for American COPD patients as well as those in Europe.

And hopefully soon we asthmatics will have our once-a-day asthma medicine. Let's keep our fingers crossed.

Facebook
Twitter

read more...

Bronchial asthma no longer used

The term bronchial asthma is no longer used.  The reason is because most asthma cases are bronchial if you think about it.  In the past bronchial asthma was separated from cardiac asthma in that bronchial patients tend to suffer from shortness of breath mainly at night.  Likewise, bronchial patients tend to have trouble exhaling, while cardiac patient don't have trouble exhaling.

Cardiac asthma patients tend to get dypneic with exertion, and those with bronchial asthma only get dyspneic when they are exposed to their asthma triggers.  In this regard, if a patient becomes dyspneic just due to exertion every time exertion occurs, then this is not asthma at all, but cardiac asthma.

Yet even though it was over 200 years ago that the difference between cardiac asthma and bronchial asthma was defined, nurses and doctors still consider all that causes dyspnea as the same:  it's all asthma. And this is why they continue to think that RT needs to be called and a bronchodilator given.

Unlike bronchial asthma, cardiac asthma patients tend to suffer from breathlessness at night but do not develop the characteristic wheezing when exhaling. In fact, the prolonged exhalation associated with asthma is not a part of cardiac asthma. While most texts note that sometimes physicians have trouble differentiating the two, I'd say that 90% of the time physicians cannot differentiate between the two.

This is why most physicians order breathing treatments for any patient that is dyspneic.  I'd also have to add here that about 99% of nurses, most doctors and many RTs cannot differentiate between cardiac and bronchial asthma.  It is for this reason so many nurses call for a respiratory therapist every time a patient becomes dsypneic with exertion. 

When a patient gets better it's not so much the breathing treatment that helps, but the boost of oxygen and rest.  Many times the patient is fine by the time I enter the room. 

This is a common occurrence after nurses and aids help a patient to the pot.


Facebook
Twitter

read more...

Bronchial asthma no longer used

The term bronchial asthma is no longer used.  The reason is because most asthma cases are bronchial if you think about it.  In the past bronchial asthma was separated from cardiac asthma in that bronchial patients tend to suffer from shortness of breath mainly at night.  Likewise, bronchial patients tend to have trouble exhaling, while cardiac patient don't have trouble exhaling.

Cardiac asthma patients tend to get dypneic with exertion, and those with bronchial asthma only get dyspneic when they are exposed to their asthma triggers.  In this regard, if a patient becomes dyspneic just due to exertion every time exertion occurs, then this is not asthma at all, but cardiac asthma.

Yet even though it was over 200 years ago that the difference between cardiac asthma and bronchial asthma was defined, nurses and doctors still consider all that causes dyspnea as the same:  it's all asthma. And this is why they continue to think that RT needs to be called and a bronchodilator given.

Unlike bronchial asthma, cardiac asthma patients tend to suffer from breathlessness at night but do not develop the characteristic wheezing when exhaling. In fact, the prolonged exhalation associated with asthma is not a part of cardiac asthma. While most texts note that sometimes physicians have trouble differentiating the two, I'd say that 90% of the time physicians cannot differentiate between the two.

This is why most physicians order breathing treatments for any patient that is dyspneic.  I'd also have to add here that about 99% of nurses, most doctors and many RTs cannot differentiate between cardiac and bronchial asthma.  It is for this reason so many nurses call for a respiratory therapist every time a patient becomes dsypneic with exertion. 

When a patient gets better it's not so much the breathing treatment that helps, but the boost of oxygen and rest.  Many times the patient is fine by the time I enter the room. 

This is a common occurrence after nurses and aids help a patient to the pot.


Facebook
Twitter

read more...

Why are food allergies on the rise???

A new study has come out showing that 1 out of every 20 school age children suffers from allergies, with the most common food allergy (in China at least) being shrimp.

Researchers at the Chinese University of Hong Kong studied over 5,000 children between 7 and 12 from the mainland, Hong Kong, Russia and India, and observed the rising trend of food allergy cases.

Obviously there is not one specific reason researchers can point their finger at as being the exact cause, yet they theorize that more children are developing food allergies because they aren't being exposed to enough germs.

That's right, as I discuss in this post, the hygiene hypothesis is an educated guess that says when an infant's immune system is not exposed to certain bacteria in the first three months of life it's immune system gets bored and starts attacking things we'd consider safe, such as allergens.

When we keep our child's environment clean we think we are doing something good, yet the hygiene hypothesis notes we may have taken clean overboard.

Thus, according to the studies experts, " the body's immune system cannot differentiate between bacteria and food enzymes. When antibodies attack food enzymes, it leads to what we know as food allergies."

So what do you do if you suspect your child has a food allergy. It actually depends. First you'll want to identify the food, and this can be done through allergy testing. Yet even if your child comes up positive for a certain food doesn't mean you should eliminate that food from his diet.

I know that some foods showed up on my allergy testing, yet since my doctors observed no significant evidence any foods were triggering asthma, they didn't eliminate any food from my diet. Taking away foods can be challenging, especially if these foods are eggs and wheat or fun foods.

So I was lucky. Yet a few of my asthmatic friends were not so lucky. Evidence showed that certain foods were triggering their asthma and allergy symptoms, and so they had to have certain foods taken out of their diet.

If the reaction to a certain food causes a rash, or difficulty breathing, then it should definitely be taken out of the diet. This might pose a challenge for school aged children because any one responsible for feeding the child must take responsibility for not feeding the child what he is allergic to.

This can pose a problem with school lunches especially if the people preparing the food are not aware of food allergies and prepare food that does not have what your child is allergic to --we'll say peanuts -- in it, for example, on the same surface a food with peanuts was just prepared.

This can also pose a problem in restaurants where food is prepared. You might ask for a food without peanuts, and you might get food with no peanuts in it. Yet you don't know if that food was exposed to peanuts.

Yet with improved vigilance and improved education, no child with a food allergy should come into contact with any food he's allergic to. While this is just one study, it provides evidence to all of us that food allergies are prevalent in our society, and we must do our part to educate ourselves.

Likewise, with the rising number of kids with food allergies, this might provide an incentive for researchers and scientists and those with the power to allocate money to such things, to work to find a cure or at least a better treatment for allergies.

FacebookTwitter

read more...

Oxygen and asthma

I have been asked many times over the course of the years I've been blogging about respiratory therapy and asthma if it is true that asthma effects your bodies ability to diffuse oxygen. The answer is most of the time no, yet sometimes yes. Allow me to explain.

In the past I have ardently noted on this blog or my asthma blog that I have rarely seen an asthmatic with a low oxygen saturation. I also have memories of waking up from anesthesia and asking for my rescue inhaler, and the anesthesiologist saying, "You don't need your inhaler, your oxygen saturation is normal."

"I don't care what your numbers say, " I said back then, "What I feel is short of breath, and I need my inhaler." Of course I didn't say it like that, my response was more of a grunt and a certain look we asthmatics have that says, "Gimme my inhaler!"

So, does oxygen effect diffusion? If so, when? To find the answer to this question allow me to refer to the god of all respiratory books: "Egan's Fundamentals of Respiratory Care." The volume I paid $63.95 for is volume 6, or the 1993 version. Yet I think the answer would be unchanged in the newer versions. If you learn different please let me know.

According to my version, the answer comes on page 472. Egan notes that early on during an asthma attack hyperventilation (rapid breathing) occurs due to anxiety, and this actually causes your bodies ability to diffuse oxygen to increase. Your oxygen saturation might even go up.

I would say that most of the asthma attacks I have are mild in nature, mainly thanks to all the good preventative medicines I take. A simple puff of my rescue medicine and my breathing is back to normal (most of the time). My oxygen levels do not decrease. My oxygen saturation does not drop below 98%.

But that hasn't always been the case. I will explain in a moment. First we need some definitions.

So what is oxygen saturation? This is also known as oxygen sat, sat, SpO2, or pulse ox. It's also referred to as the 5th vital sign after heart rate, respiratory rate, temperature and blood pressure. It's the percentage of oxygen you inhale that makes it to your blood stream.

More specifically, in your blood you have red blood cells (RBC). In the center is a protein called hemoglobin that makes the RBC look kind of like a boat or a donut. When the RBC comes into contact with the lungs the oxygen jumps on board the boat and takes a ride to a cell somewhere in the body.

When an oxygen sits on the RBC your blood is red. When oxygen hops off the RBC your blood has a darker color. Regardless, the oxygen saturation basically is a percentage of these hemoglobin that are saturated with oxygen. So, if I say your sat is 98%, that means that 98% of the RBC boats in your lungs have an oxygen on board.


Your sat is measured by a probe gently and painlessly placed over your finger, or ear, or toe (although usually just a finger will suffice).

What is PO2?


Without going into too much detail, this is the partial pressure of oxygen. In your arteries, which carries oxygenated blood from your lungs to tissues of your body, a normal PO2 is about 100. If this drops to 60 you have hypoxemia, which means low oxygen in the blood.


So as your asthma worsens, your PO2 may decrease. The only way to know what your PO2 is to draw an Arterial Blood Gas (ABG). This is an invasive poke where an RT puts a needle into your radial artery, which runs right along your radial nerve on the thumb side of your wrist.


Thankfully, however, modern wisdom gave us pulse oximeters, because there is a direct link between your PO2 and yoru oxygen saturation. Generally speaking, your SpO2 is 30 higher than your PO2, so if your SpO2 reading is above 90, you know your PO2 is above 60. As your sat drops below 60 you know your PO2 is likewise dropping to significant lows.


(For more detail on this see my post on the oxyhemoglobin dissociation curve.)


Pulse oximeters did not exist until the early 1990s, so those who took care of me when I was a hardluck asthmatic in the 1970s and 1980s were not able to check my oxygen levels. However, a tel-tale sign of low oxygen in the blood is blue lips and fingerstips.


There were many times I had this sign.


So what does this have to do with asthma?


I had an attack in 1998 and I have the results of my blood gases, and back then my PO2 was 64 and my sat was 94. This was still acceptable, yet you can see why my doctors might have been getting worried, especially since nothing was making my asthma better.

In the early stages of asthma, or during a mild asthma attack, your sat will be normal or increased. If you stay calm it will continue to be normal. If you become anxious and hyperventilate (breathe fast) it may actually be higher than normal.

However, as your asthma attack progresses, and your air passages become increasingly narrowed and blocked, even though you are breathing fast and heavy your lungs ability to diffuse oxygen is diminished. It is at this time your sat begins to decline.


Oxygen therapy:




As your asthma becomes even worse, your sat may drop further.

Facebook
Twitter

read more...

Oxygen and asthma

I have been asked many times over the course of the years I've been blogging about respiratory therapy and asthma if it is true that asthma effects your bodies ability to diffuse oxygen. The answer is most of the time no, yet sometimes yes. Allow me to explain.

In the past I have ardently noted on this blog or my asthma blog that I have rarely seen an asthmatic with a low oxygen saturation. I also have memories of waking up from anesthesia and asking for my rescue inhaler, and the anesthesiologist saying, "You don't need your inhaler, your oxygen saturation is normal."

"I don't care what your numbers say, " I said back then, "What I feel is short of breath, and I need my inhaler." Of course I didn't say it like that, my response was more of a grunt and a certain look we asthmatics have that says, "Gimme my inhaler!"

So, does oxygen effect diffusion? If so, when? To find the answer to this question allow me to refer to the god of all respiratory books: "Egan's Fundamentals of Respiratory Care." The volume I paid $63.95 for is volume 6, or the 1993 version. Yet I think the answer would be unchanged in the newer versions. If you learn different please let me know.

According to my version, the answer comes on page 472. Egan notes that early on during an asthma attack hyperventilation (rapid breathing) occurs due to anxiety, and this actually causes your bodies ability to diffuse oxygen to increase. Your oxygen saturation might even go up.

I would say that most of the asthma attacks I have are mild in nature, mainly thanks to all the good preventative medicines I take. A simple puff of my rescue medicine and my breathing is back to normal (most of the time). My oxygen levels do not decrease. My oxygen saturation does not drop below 98%.

But that hasn't always been the case. I will explain in a moment. First we need some definitions.

So what is oxygen saturation? This is also known as oxygen sat, sat, SpO2, or pulse ox. It's also referred to as the 5th vital sign after heart rate, respiratory rate, temperature and blood pressure. It's the percentage of oxygen you inhale that makes it to your blood stream.

More specifically, in your blood you have red blood cells (RBC). In the center is a protein called hemoglobin that makes the RBC look kind of like a boat or a donut. When the RBC comes into contact with the lungs the oxygen jumps on board the boat and takes a ride to a cell somewhere in the body.

When an oxygen sits on the RBC your blood is red. When oxygen hops off the RBC your blood has a darker color. Regardless, the oxygen saturation basically is a percentage of these hemoglobin that are saturated with oxygen. So, if I say your sat is 98%, that means that 98% of the RBC boats in your lungs have an oxygen on board.


Your sat is measured by a probe gently and painlessly placed over your finger, or ear, or toe (although usually just a finger will suffice).

What is PO2?


Without going into too much detail, this is the partial pressure of oxygen. In your arteries, which carries oxygenated blood from your lungs to tissues of your body, a normal PO2 is about 100. If this drops to 60 you have hypoxemia, which means low oxygen in the blood.


So as your asthma worsens, your PO2 may decrease. The only way to know what your PO2 is to draw an Arterial Blood Gas (ABG). This is an invasive poke where an RT puts a needle into your radial artery, which runs right along your radial nerve on the thumb side of your wrist.


Thankfully, however, modern wisdom gave us pulse oximeters, because there is a direct link between your PO2 and yoru oxygen saturation. Generally speaking, your SpO2 is 30 higher than your PO2, so if your SpO2 reading is above 90, you know your PO2 is above 60. As your sat drops below 60 you know your PO2 is likewise dropping to significant lows.


(For more detail on this see my post on the oxyhemoglobin dissociation curve.)


Pulse oximeters did not exist until the early 1990s, so those who took care of me when I was a hardluck asthmatic in the 1970s and 1980s were not able to check my oxygen levels. However, a tel-tale sign of low oxygen in the blood is blue lips and fingerstips.


There were many times I had this sign.


So what does this have to do with asthma?


I had an attack in 1998 and I have the results of my blood gases, and back then my PO2 was 64 and my sat was 94. This was still acceptable, yet you can see why my doctors might have been getting worried, especially since nothing was making my asthma better.

In the early stages of asthma, or during a mild asthma attack, your sat will be normal or increased. If you stay calm it will continue to be normal. If you become anxious and hyperventilate (breathe fast) it may actually be higher than normal.

However, as your asthma attack progresses, and your air passages become increasingly narrowed and blocked, even though you are breathing fast and heavy your lungs ability to diffuse oxygen is diminished. It is at this time your sat begins to decline.


Oxygen therapy:




As your asthma becomes even worse, your sat may drop further.

Facebook
Twitter

read more...