jagdkampf
02-22-02, 20:29
Now here is something that I actually know something about.
The difficult airway falls into several different categories:
1. The anatomically difficult airway
2. The traumatized difficult airway
3. The emergent airway
The management of the difficult airway is determined by which presentation you are faced with.
Lets look at the anatomically difficult airway first. For purposes of simplicity, I will deal with these as separate entities. Although, you may be presented with combinations of the above. The key to dealing with the anatomically difficult airway is recognition. In anesthesia, we do an airway assessment prior to any anesthetic. This consists of several different observations. The first is the appearance of the structures within the mouth and throat. You instruct the patient to open their mouth as wide as possible and say aaahhh. In a normal airway you will see the following: (1) The tonque should extend and be somewhat flattened on top. (2) You should see the uvula (the little hangy down thing) and the palatine arch (a slight curve on either side of the uvula). (3) you should be able to see the posterior oropharynx behind the uvula and palatine arch. (4) observe the condition of the dentition. Any loose or bad teeth? If you can easily observe all these things and the teeth are in good shape, congratulate yourself, you probably have a manageable airway. But, don't stop yet. You still have a couple of more tests.
Note the size and relationship of the head and neck. Is the size of the neck proportionate to the head?
Examine the relationship of the mandible to the Adam's apple (thyroid cartilage). This can be done by laying the fingers on the underside of the chin. You should have three finger breadths between the tip of the chin and Adam's apple. Any less than this could be an indication of difficult airway.
Next, gently grasp the back of the head and push it forward. Can the patient place his chin on his chest without pain of difficulty?
Ask the patient a few pertinent questions. (1) Do you snore at night. (you might want to check with the signifigant other or family member on this one as well)
(2) Does the patient every stop breathing at night or gasp for air?
You have just done an airway assessment. Now, what do you do with that information?
If everything appears normal, great. You can proceed as necessary. If not, you must make a determination on how difficult an airway you may have. In anesthesia, we grade the airway. The scale we use is called a Mallampatti score. It runs from 1 to 4. 1 being an essentially normal airway and a 4 being an extremely difficult airway. Let's do a quick run down on this by example. On an exam of the mouth and oropharynx, you can't see the back of the mouth or pallatine arch and you can just barely see the uvula. The teeth are intact and normal. This would be graded as a Mallampatti 3. Next, you place your fingers under the chin and only two fingers will fit. Add 1 difficulty point. On observation of the neck and head, you notice that the neck is very large compared to the head and that the head appears to set directly on the shoulders. Add another difficulty point. When you attempt to push the patients head forward, you obstruct their breathing. Add another difficulty point. The patients family tell you that he sounds like a chain saw at night and that he occasionally stops breathing then resumes and gasps for air. He often wakes feeling very fatigued. Add another difficulty point. Ok, so lets review your score. You assigned him a Mallampatti 3 with 4 difficulty points. This indicates that you have a moderate to severe difficult airway. Now that you know this, what to you do?
{I will continue this in the next post} Any questions so far?
Jag
The difficult airway falls into several different categories:
1. The anatomically difficult airway
2. The traumatized difficult airway
3. The emergent airway
The management of the difficult airway is determined by which presentation you are faced with.
Lets look at the anatomically difficult airway first. For purposes of simplicity, I will deal with these as separate entities. Although, you may be presented with combinations of the above. The key to dealing with the anatomically difficult airway is recognition. In anesthesia, we do an airway assessment prior to any anesthetic. This consists of several different observations. The first is the appearance of the structures within the mouth and throat. You instruct the patient to open their mouth as wide as possible and say aaahhh. In a normal airway you will see the following: (1) The tonque should extend and be somewhat flattened on top. (2) You should see the uvula (the little hangy down thing) and the palatine arch (a slight curve on either side of the uvula). (3) you should be able to see the posterior oropharynx behind the uvula and palatine arch. (4) observe the condition of the dentition. Any loose or bad teeth? If you can easily observe all these things and the teeth are in good shape, congratulate yourself, you probably have a manageable airway. But, don't stop yet. You still have a couple of more tests.
Note the size and relationship of the head and neck. Is the size of the neck proportionate to the head?
Examine the relationship of the mandible to the Adam's apple (thyroid cartilage). This can be done by laying the fingers on the underside of the chin. You should have three finger breadths between the tip of the chin and Adam's apple. Any less than this could be an indication of difficult airway.
Next, gently grasp the back of the head and push it forward. Can the patient place his chin on his chest without pain of difficulty?
Ask the patient a few pertinent questions. (1) Do you snore at night. (you might want to check with the signifigant other or family member on this one as well)
(2) Does the patient every stop breathing at night or gasp for air?
You have just done an airway assessment. Now, what do you do with that information?
If everything appears normal, great. You can proceed as necessary. If not, you must make a determination on how difficult an airway you may have. In anesthesia, we grade the airway. The scale we use is called a Mallampatti score. It runs from 1 to 4. 1 being an essentially normal airway and a 4 being an extremely difficult airway. Let's do a quick run down on this by example. On an exam of the mouth and oropharynx, you can't see the back of the mouth or pallatine arch and you can just barely see the uvula. The teeth are intact and normal. This would be graded as a Mallampatti 3. Next, you place your fingers under the chin and only two fingers will fit. Add 1 difficulty point. On observation of the neck and head, you notice that the neck is very large compared to the head and that the head appears to set directly on the shoulders. Add another difficulty point. When you attempt to push the patients head forward, you obstruct their breathing. Add another difficulty point. The patients family tell you that he sounds like a chain saw at night and that he occasionally stops breathing then resumes and gasps for air. He often wakes feeling very fatigued. Add another difficulty point. Ok, so lets review your score. You assigned him a Mallampatti 3 with 4 difficulty points. This indicates that you have a moderate to severe difficult airway. Now that you know this, what to you do?
{I will continue this in the next post} Any questions so far?
Jag