Now that graduation is behind me (yay!), I've been trying to study for boards (boo!).  But why should I have all the fun?  Let me take you on my journey of learning by sharing with you this awesome video I found.  For those of you who have always wondered what it's like to be a red blood cell, THIS IS YOUR LUCKY DAY.

In studying for my final exam, it occurred to me that I haven't posted a coagulation pathway memory aid that's been passed around our class.  It seems as though we cover the coagulation cascade every semester and, every time it's covered on an exam, I thank my lucky stars for this thing:

1. The top row is “in a line” so it is the “intrinsic” pathway
2. Then pathway through Factor 7 starts from the outside so it is the “extrinsic”
3. The intrinsic pathway is longer so it is measured by PTT, the extrinsic pathway is shorter so it is measured by the PT
4. The extrinsic pathway looks like a gun and guns are used in war so you monitor Warfarin (Coumadin) using the PT (extrinsic pathway function)
5. The gun of the extrinsic pathway is shot using the your “trigger finger” [TF] so the extrinsic pathway is activated by the TF of the body or tissue factor
6. 10 is special so all the factors surrounding 10 (9, 2, 7 and 10 itself) are a little special too—all these factors are Vitamin K dependent (ie require Vit. K to be made)

1. Baby does not receive Vit K shot which factors are decreased?
2. Boy has Hemophilia A.  Which clotting test is prolonged?
3. Girl has Von Willenbrand’s Disease.  When she beings to clot which factor can build up?
4. Old man overdoses on Coumadin.  What do you give to help reverse it and how do you monitor his progress?
5. Which pathway is activated when the vessel is damaged?

1. 2, 7, 9, 10
2. Hemophilia A produces a defect in factor 8.  PTT is prolonged, but PT is normal since it bypasses factor 8
3. vWF is a part of the factor 8 complex.  Factor 9 has the potential to build up since it will not be converted to factor 10.  This is another example where the PT may be normal.
4. Coumadin competively inhibits the production of Vit. K factors so you give large doses of Vit. K.  Monitor with PT
5. Endothelial damage releases TF.  Extrinsic pathway is activated.

There you have it!  It may not help everyone, but it definitely helps me remember the factors and steps of the coagulation cascade.


Alright, enough of my procrastinating...


* My classmate originally found the memory aid online.  If anyone knows who originally came up with the idea, let me know so I can give him/her credit for their awesome handiwork!

After a looooong night of studying, I'm about to leave the house to take my second-to-last (woot!) exam.  The topic today is neuromuscular blockers and reversals.  We've covered this material before - during one of the first few weeks of school, actually - but are covering it in greater detail this go around.  One thing that's always tripped me up is keeping two of the reversal agents, pyridostigmine and physostigmine, straight.


As you may recall, pyridostigmine is a quaternary amine cholinesterase inhibitor.  Due to it's chemical structure, it is highly ionized and does not easily cross membranes, including the blood brain barrier.  It is often used to treat Myasthenia Gravis due to it's longer duration of action.  Physostigmine, on the other hand, is a tertiary amine cholinesterase inhibitor.  As such, it is lipid soluble and crosses the blood brain barrier with ease.  It is therefore used to treat Central Cholinergic Syndrome, which typically affects children given overly large amounts of atropine or scopolamine, two cholinergics/antimuscarinics which can also cross the blood brain barrier and cause CNS effects.  Physostigmine was also previously used to reverse lingering CNS effects following anesthesia.  For this reason, it was given the trade name Antilirium.  (Clever, right?)


Although the two anticholinesterase drugs are quite different from one another, their names are similar and I was having a hard time differentiating between the two.  But, I figured out a memory aid and thought I'd be all Angelina Jolie with you guys and share.  I now refer to physostigmine as "psychostigmine", in light of it's CNS effects and unique ability to cross the blood brain barrier.  This helps me differentiate it from pyridostigmine.


Happy studying!

Thanks to Laura and Carie for finding and forwarding some cool anesthesia-related online content!  Laura sent me the link to the BIS website (here) where you'll find some automated anesthetic simulations.  And Carie told me about a site called "Airway World" (here), which is pretty much where I feel I've been stranded and left to die for the past 18 months.  Just sayin'.

Happy surfing!

I'm about to sit for my last respiratory exam and, while reviewing the test material, I was reminded of a neat video one of our CRNA instructors presented to us during class a few weeks ago.  He was covering content related to ventilators and ventilator modes and used the following to illustrate the effectiveness of CPAP and PEEP at reducing atelectasis and maintaining alveolar ventilation.  Pretty cool!

Now go forth, and dial in some PEEP!

My classmate Lashaunda (of paralytic dosing fame) just passed along another study aid which I liked and thought might be of help to other SRNAs who read this blog.  Not only will this post enable you remember the doses of the following sedatives, but I can now officially claim that this website isn't completely useless!  Double win.

We are currently studying respiratory anatomy, physiology, and associated disease states.  My buddy Adam, who apparently has entirely too much time on his hands*, found a cool website covering flow volume loops and emailed the link to the rest of our class.  So, from Adam, to me, to you: enjoy!

http://www.spirometrie.info/fvc.html

* Says me, who maintains a blog in between classes, clinical obligations, and happy hours.  Glass houses, Amy.  Glass houses.

Image via here]

My classmates and I spent Thursday and Friday of last week at Pediatric Life Support and Neonatal Resussitation Program training and certification courses.  During this time, we discussed the uses, benefits, and insertion techniques of intraosseous catheters. 

My classmate, Kathryn, suggested that I find and post a video of IO catheter insertion on the blog.  My suggestion?  That you watch the following video as you sit down for dinner.  It's, like, the best diet ever!

(On a side-note: for those of you planning to attend Baptist's Nurse Anesthesia Program in the future, don't spend your money or time trying to get certified or recertified in BLS, ACLS, PALS, or NRP prior to matriculation.  You and your classmates will all be required to take these courses together once the program begins to ensure that everyone is covered during their clinical rotations while in school.  Of course, you must remain appropriately certified for your area of nursing in the meantime.  Just a heads up!)

You know when you hear about new products or ideas and your all, "man... I so had that!"?  You know, like the way you felt after you first laid eyes on "The Slanket".

...or the "Split Ring Key".



Well, my classmate, Lashaunda, just sent us all an email with a helpful hint for remembering dosages of paralytic agents and it's just so brilliant that I can't help but kick myself for not thinking of it first and then patenting the heck out of it.

CVP: Cisatracurium, Vecuronium & Pancuronium - 0.1 mg/kg
MAR: Mivacurium, Atracurium, & Rocuronium - 0.2, 0.4, & 0.6 mg/kg (respectively)

Mad props, Lashaunda.  Mad props.

Dr. Rieker, my program director, recently educated our class on the intricacies of the myoneural junction.  He stressed that, in order for acetylcholine to pass into the effector cell membrane and initiate a response, acetylcholine receptors must open to create channels through which these molecules can pass.

This action requires that both alpha subunits of the receptor are activated.  If only one alpha subunit is activated, the receptor will remain closed.  Dr. Rieker then utilized the following video to drive this point home:


Later during that same lecture, while on the topic of myotonia, Dr. Rieker again surprised us with this gem:

In studying for last week's airway exam, I came across a few really neat online offerings.  The first is a video of the vocal cords during speech:

The other was discovered by my classmate, Dave.  It's a website titled "The Interactive Larynx" and we called on it to clarify a number of points during our Sunday night study session.  Be sure to use the "smiley face" scroll bar to add structures to the larynx and click on the boxes lining the bottom of the page to see diagrams or watch short videos of specific areas of the airway!

Oh, World Wide Web.  How do I love thee?  Let me count the ways...

We recently had the opportunity to hear one of Baptist Hospital's Anesthesiologists discuss airway considerations.  He mentioned an online video, filmed and uploaded through WFUBMC, which demonstrates a Lightwand Intubation.  This is one of the difficult airway techniques that we were able to practice last week in the cadaver lab and it was pretty incredible to see and do.

Click here to view the full list of videos related to Lightwand Intubation.  (Scroll to the bottom to see the technique in practice.)

If you're considering anesthesia school, this alone should sell you on the idea.  I mean, come on, we get to play with light wands for heavens sake. They're like the health care provider's version of a lightsabre!

... Just don't show up to your graduate school interviews wearing braided hair buns on either side of your head.  Consider yourself warned.

[Click on photo for source information]

Both Kathleen O'Connor, our CRNA airway anatomy lecturer, and Dr. Steve Galyon, our cadaver lab instructor, mentioned a common mistake made by health care professionals when accessing the nasopharynx during nasal intubation, NT suctioning, nasogastric tube insertion, or nasal airway placement. Many of us - myself included - did so using a "rainbow" motion, as if following the angle of the patient's nose. This, however, can cause internal damage to the tissues of the nasal cavity as the Superior, Middle, and Inferior Nasal Concha often impede this route, as illustrated by the diagram below.


Instead, the proper way to pass the device is to direct the instrument across the base of the nasal cavity. This means that if your patient is lying in a supine position, you should be aiming for the floor (perpendicular to the patient).

Once that's completed, the only thing left to do is push this:



[Click on diagram for source information]

Our first day in the cadaver lab was both exciting and informative! Doctor Steve Galyon, a former CRNA who later became an ENT surgeon and is now completing his residency in Anesthesia (my brain hurts just thinking about all that schooling...) was on hand to educate our class on airway structure identification and manipulation techniques.

Note: An unidentifiable human cadaver is pictured in the following photos. Out of respect for those who may not wish to view these images, I've posted them after the jump. Please click on the title of this post (i.e. "Cadaver Lab Photos") to view.

UPDATE: I've removed the majority of the photos in which a significant amount of anatomy is visible.  Instead, I've included drawings or diagrams of a few techniques we were shown.

Unlike most nondepolarizing neuromuscular relaxing agents which are metabolized via the liver, atracurium (Tracium) is cleared from systemic circulation via Hofmann Elimination.  (And secondarily by ester hydrolysis, but that's neither here nor there...)  Thus, at standard temperature and pH, the drug is spontaneously metabolized.  Atracurium clearance is therefore not dependent on organ function and may be administered to patients with liver or kidney impairment, for example.

But what about patients who don't meet the requirements of "standard temperature and pH"?  Well, Hofmann Elimination still occurs, just at varied rates.  It is decreased by acidosis and diminished body temperature.  Conversely, states of alkalosis and heightened temperature increase the metabolism of Hofmann Eliminated drugs.

The way I remember this is easy: As pH and temperature decrease, Hofmann Elimination also decreases.  As pH and temperature increase, Hofmann Elimination increases.  Thus, a febrile patient, for instance, would require a higher dose (or more frequent dosing) of atracurium to remain pharmacologically paralyzed than would a normothermic patient.

[Click on image for source information]

I'm currently preparing to take my first examination, covering gases and gas machines.  Like most SRNAs, I do not have a degree in physics - and for good reason.  Nevertheless, anesthesia providers must know how to deliver and manipulate the flow of gases if they are to effectively oxygenate and anesthetize patients.  So, physics background or not, we need to learn and remember a whole heck of a lot regarding the functions and behavior of gases.

One of the first things we were taught?  The behavior of all gases is reliant on three characteristics: temperature, pressure, and volume.  This gives rise to three "ideal" gas laws:


Boyle's Law
At a constant temperature, the pressure of a gas is inversely proportional to its volume.


Charle's Law
At a constant pressure, the temperature of a gas is directly proportional to its volume.


Gay-Lussac's Law
At a constant volume, the temperature of a gas is directly proportional to its pressure.

One can imagine how difficult it might be to keep these various laws straight.  Fortunately, I have found from past experience that the more inappropriate a study aid is, the more likely I am to remember it.  (Sorry, mom!)  For example, that old trick to remembering the order of cranial nerves that begins with "On Old Olympus..."?  Yeah, it never worked for me.  (Note that the reason I didn't finish typing the mnemonic is not that I'm lazy, but because I literally can't remember the rest of it.)  However, the second I heard the vulgar "Oh Oh Oh, To Touch And Feel A Girl's Vagina, AH..." I was sold.  Now, cranial nerves are a snap.

Well, the same holds for the method I devised to remember the three ideal gas laws.  They are as follows:


Boyle's Law
Boyle's is similar to "boils", which relates to a hot (temperature) liquid.  Thus, you hold temperature constant.


Charle's Law
The name "Charles" reminds me of Prince Charles.  Prince and pressure both begin with the letter "p".  In this case, you hold pressure constant.


Gay-Lussac's Law
Finally (and here's where the vulgarity sneaks in), "gay" is a term often related to sexual orientation.  "Vagina" is a term that denotes a sexual organ.  Vagina and volume both begin with the letter "v".  You therefore hold volume constant.

It's a bit crude and may not work for everyone, but it has certainly helped me to differentiate each law from the others and I've been told by a few classmates that it's worked for them as well.

[Click on image for source]

Today was our first clinical conference.  You see, every Wednesday morning at the ungodly hour of 0645, we are required to attend a conference in which the Baptist hospital CRNAs and (often an anesthesiologist) discuss any particularly interesting cases or topics related to the field of anesthesia.  I didn't quite know what to expect, which is probably for the best considering that if I'd anticipated the number of questions us newbies would be asked after a mere 2 days of orientation, I would have gotten very little sleep last night.

Fortunately, Dr. Tobin, the Chair of the hospital's Anesthesia Department, lead the discussion and really excelled at explaining the concepts that were covered.  The case at hand involved a patient who suffered complications on the operating table following an apparent laryngospasm.  What I found most interesting was Dr. Tobin's description and explanation of flash pulmonary edema.  It caused me to realize that, though I'd cared for a number of patient's diagnosed with this affliction while an ICU nurse, I had never before grasped the mechanism of injury.

According to Dr. Tobin's lecture, flash pulmonary edema may occur after too much pressure has been exerted on the pulmonary artery by way of the alveoli.  How might this happen?  First, it's important to understand that during normal respiration, the vacuum created in the alveolar spaces (the intra-airway pressure) during inspiration ranges from -5 to -10 mmHg.  However, an obstruction or laryngospasm exacerbates these figures as an even greater inspiratory force is exerted in an attempt to overcome the airway constricture.  In such cases, the intra-airway pressure during inspiration may register at -60 to -100 mmHg.  This massive pressure swing causes the alveoli to become more porous and, because pulmonary artery pressure is only around 25/15 mmHg (systolic/diastolic), fluid from the PA intravascular space weeps into the surrounding pulmonary tissue. This flooding of alveolar spaces not only prevents oxygen exchange, but also inactivates tissue surfactant.  Although this substance is slowly replaced by the alveoli, patients often require mechanical ventilation with a corresponding ICU stay while their lungs regain function.

I don't know about you, but my brain feels bigger.

[Click on image for source]