We had a quick quiz at the end of EENT today. The teacher used it with a dual purpose agenda with one reason being to account for attendance during the second hour and the 2nd reason was to give everybody that turned it in an extra credit point! Those extra credit points don't come around to often so it was a nice surprise and the kid here got TWO extra credit points because I got all the answers correct!!! :D
I tried laying down for a nap but kept getting phone calls & text messages so it looks like I'm maybe up for the duration now. I've got 12 hours before class starts again tomorrow at 7:20 so, a good 10 hours to be able to study for my Phys Dx midterm. I'll have to pick up some soda from QT and get some coffee brewing to pull this off.
Geez ...some of the text I was getting was from a classmate who wanted my class notes for EENT. We just started new material last week ... I'm not naming names or anything but this is the person who tutored me prior to our last test and I ended up with a B+ with her help but she just told me she failed it?!
Well, I need to learn some heart sounds and finally embrace a sheet of paper the teacher wrote out by hand then made copies of for everyone in the class. The heart has probably been one of my favorite body parts for as long as I can remember. I remember looking at the heart in the World Book encyclopedias my parents first bought way back in the 70s so you'd think I'd be diving into this stuff like it's nobody's business. I'm going to finally look at that sheet and try typing it out here as a first exposure. Then I'll probably copy it long hand as well as read through the book to help gain a greater appreciation for what I'm looking at.
S1 ------systole--->S2 --------diastole----->S1
McTc<-(regurge)->AcPc
AoPo<-(stenosis)->MoTo
OK, well that first line shows S1 then S2, then S1 again. dang....I'm thinking I used to integrate the Gaussian curve to one just for the fun of it on the back of placemats at I-Hop so I can certainly figure this out. The Gaussian curve was an indefinite integral that needed to be broken up into two integrals both with limits approaching negative and positive infinity then it took two substitutions as well as knowledge about the gamma function......
Anyway...S1 and S2 represent the "lub dub" sounds the heart makes. No, it doesn't ever sound like lub dub but that's how it's expressed. The lub and dub sounds are fairly close together then there's a slight pause and then we hear the lub dub sound again and hopefully it keeps doing that for a very long time. The time gap between the lub and dub, (S1 and S2) is when the heart is contracting and that's known as systole. The longer time gap between S2 and the next S2 is when the heart is relaxed and refilling with blood. Much of that refilling is done passively, that is, the heart is just chillin and letting blood fill it's chambers whereas the systolic phase of the heart beat is active contraction and squeezing the blood out to our lungs and the rest of our body.
Underneath S1 we have McTc. The little 'c' stands for close or closing. The M stands for Mitral and the T stands for Tricuspid. Thus, S1 is the sound made when the mitral valve and tricuspid valve close. Those valves close when the ventricles start to contract to push blood out of the semilunar vavles (both the aortic and pulmonary semilunar valves)
If you've ever had a door open on a windy day and you all of a sudden hear it slam shut, it's because of a pressure difference and kind of the same principle.
After a good majority of the blood has been squeezed out of the aortic and pulmonary valves then the pressure in the ventricals becomes lower than the pressure in the arteries the blood has just been pushed into and the semilunar valves close and that's represented by AcPc (aortic close, pulmonary close)
....I've been looking through a couple books & study guides... I do believe my butt is about to be kicked. Which reminds me, I had my neurology midterm this morning. I had a pretty nice start to the day and headed out at 4:15 a.m. and, after failing to find a gas station or McDonald's open that early to get coffee still managed to stroll into school at 5 a.m.
Got some worthwhile studying in and there were about 10 of us down in the cafeteria to bounce questions off each other which always helps accelerate the learning process.
Gotta focus and learn specifically about ....
D - Diaphragm side of the stethoscope - better for picking up the relatively high-pitched sounds of S1 and S2, the murmurs of aortic and mitral regurgitation and pericardial friction rubs.
B - The bell side of the stethoscope - more sensitive to the low-pitched sounds of S3 and S4 and the murmur of mitral stenosis. The bell needs to be applied lightly to the patient or sounds may be lost.
S3 - third heart sound - occasionally this sound is heard at the beginning of the middle third of diastole... Use the bell side. With the right ventricle the sound is increased with inspiration. With the left ventricle, S3 is heart best with the patient laying on their left side (affectionately referred to as the Left lateral decubitus position)
S4 - fourth heart sound aka atrial heart sound - normally only heard with a phonocardiogram and occurs around the beginning of the last third of diastole
WOW! ...I just posted a link for heart sounds up on facebook and have been following a conversation between a fellow student and a person who will become a nurse early next year ...
fellow student - mentions learning about heart sounds
nurse 2 be - oh yeah, a lady is coming in next week for an hour an a half to teach us all about that and how to read EKGs!
I've been learning about the heart every semester since May of 2008 and I'd hardly consider myself an expert.
I think I'm starting to understand the attitude of doctors, some doctors anyway and maybe why I've have been a possible annoyance to them in the past due to thinking I knew something when I didn't really know much of anything. I'm noticing the differences more and more everyday between my knowledge base and that of the lay person. This is probably the perfect semester for us to be having patient communication...
Let's see, for classes we've had which have pertained to the heart we've got prerequisite anatomy & physiology classes, biochemistry, gross anatomy, histology and cell biology, microbiology, Neuroanatomy, physiology, pathology, embryology, neuromusculoskeletal diagnosis, nutrition, cardiorespiratory diagnosis, laboratory diagnosis, toxicology, physical diagnosis, neurology, diagnostic imaging, clinical reasoning and pediatrics.
There's been a relationship to the heart in every single one of those classes, all from different angles, perspectives and depths and I'm sure we'll be learning more pertaining to the heart, as well as all major systems in upcoming classes as well.
anyway ...i wish i could learn about all these sounds in an hour an a half and even with all this study, we're still just scratching the surface, just enough to be in awe of a cardiologist.
EC - Ejection clicks, happen when semilunar valves open
OS - Opening Snaps, happen when AV valves open
an AV valve (S1) will close in about 0.14 second while the semilunar valves (S2) close in about 0.11 seconds. The semilunar valves are more taut than the AV valves hence, the faster closure.
The mitral valve is louder than the tricuspid valve due to the higher pressure on the left side of the heart
Geezzzzz.... According to Bates (our Phys Dx textbook) the splitting of S1 does not vary with respiration. Accroding to the paper our teacher handed out, the splitting of S1 is associated with expiration but according to two different websites the split S1 is more greatly appreciated during inspiration because inspiration delays the closure of the tricuspid vavle due to increased venous return (in a normal person anyway) I guess I'll go with the teachers handout even though the website explanation makes sense.
I've got a boatload of other sounds to get through ...thinking I might take a shower to help change my state of mind then get back to it. Fridays are always my toughest days. My eyes seem to be shaking as I'm reading.
Posts
No comments:
Post a Comment