Summary of Blood-Pressure station

blood pressure taking is one of the very basic station, and because of this, we're supposed to do it with a snap of our finger.

the marking criteria may be quite stringent due to this fact, and so we have to get all of the details correct in order to score.

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flow of events-

1. GIEP
2. wash hands
3. the 6 questions.
4. expose the arm.
5. inspection of arm
6. palpate the radial and brachial artery
7. wrapping of cuff onto arm
8. palpitory method and SBP estimation
9. auscultatory method.
10. report.
11. thank patient
12. wash hands
13. leave.

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GIEP-

in the BP station, we're expected to actually explain our procedure to the patient. although it may seem very, very obvious to us that BP-taking will involve wrapping the cuff around the patient's arm, it may not be obvious to the patient. hence -

hello, my name is --------, i am a -- year medical student, i would like to take your BP, this will involve me wrapping this (cuff) around your arm, it may cause some tightness but it shouldn't be painful. do i have your permission?

you don't have to follow exactly what is stated, but just remember to EXPLAIN.

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wash hands - refer to the general precautions
http://tatsukiatimu.blogspot.com/2010/04/first-of-all.html

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the questions
we are required to ask several questions, to check if the patient has been exposed to factors which may affect their BP. in no particular order;

• have you had any caffeinated drinks this morning or last night? - caffeine raises BP, and its half-life is more than 5 hours.
• have you had enough sleep last night? - lack of sleep raises BP.
• have you had any exercise this morning? - exercise raises BP.
• Do you have any long-standing illnesses, eg. hypertension?
• Are you on any medication now? - some medications are aimed to decrease BP, and some drugs have side-effects of raised BP- e.g. Oral contraceptives
• do you smoke? - smokers generally have high BP.
• is the room warm enough for you? - cold environment raises BP.

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Proper exposure of the arm.
just... remember to do it.
you need to expose enough so that the cuff won't wrap around the patient's clothes.

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inspection of the arm

• inspect the arm for the presence of (or the lack of) any scars, swellings, discolourations.
• you may also check for muscle wasting.
• anything attached to the patient? e.g. IV line. 
• important thing to look for, is an Arterio-venous fistula.

AV fistulas are seen on dialysis patients, and their purpose is to provide a large vessel for a large-bore needle to be put on.
if you see an AV-fistula on the arm, do NOT take BP on that arm.
AV fistula looks like this -

pretty obvious, right?

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palpation of the arteries.

to measure the BP of a patient, we need to know where the pulses are.

the pulses involved are;

radial pulse

brachial pulse

we're expected to know the anatomical locations of those 2 pulses.

radial pulse is lateral to the tendon of flexor carpi radialus,

brachial pulse is medial to the tendon of biceps brachii.
if you're new to the medical lingo, its difficult but you have got to remember them by heart - typical VIVA question.

if you feel its difficult to feel for the brachial pulse, ask the patient to hyper-extend the arm. you should find it easier that way.

after locating the 2 pulses, there is no harm saying that it is present, that the rate and rhythm is normal, volume is sufficient.

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Cuff Wrapping

this step seems simple, but apparently some students completely mess up at this part.

practice wrapping cuff around patient's arm.

people mess up, because they don't know which side faces out. 
look at the arrows, put the arrow mark onto the brachial pulse, and wrap it. you won't go wrong this way.

be wary of the position and tightness of the cuff - it should be 2 fingers away from the cubital fossa,

it should fit snugly - check by sliding in one or two fingers. it should feel just nicely tight.

just FYI, a too-small cuff will cause a higher-than-actual reading, and too-large cuff vice versa.

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Palpitory method

palpitory method involves...

1. feeling for the radial pulse
2. inflate cuff while feeling for the radial pulse
3. when it comes to a point when you do not feel the radial pulse, pump 20Hg more.
4. slowly release the air valve, to reach the point when you feel the radial pulse again
5. the point at which you feel the radial pulse is the estimated systolic blood pressure
6. deflate cuff. make sure the patient is comfortable.

we will need to take a preliminary reading before we get the actual blood pressure.

now, why do we have to take the trouble to do the palpitory method? whenever we go to the doctor, and do we see the doctors taking the trouble to do the palpitory method? so why are we required to do this step?

there are several reasons why we do this before the auscultatoty method.

1. because we're basically amatures, we need to get an estimate before we do one-off. the palpitory method allows us to estimate the systolic blood pressure relatively fast.
2. there is this thing called Auscultatory gap. this is the region of pressure in which we do not hear any karatkoff sounds. in other words, there may be a region of blood pressure when we do the auscultatory method, where we do not hear anything, and mistake them for the pressure above the systolic blood pressure.
   this can be seen in hypertensive patients, and it causes us to mistakingly take the lower border of the auscultatory gap as the systolic blood pressure when in the actual fact, there is a much higher blood pressure.
   thankfully even though there is no sound, there is still blood flow, and hence we can still feel the pulse. using the palpitory method will enable us to estimate the correct systolic blood pressure.
3. palpitory method could be used in noisy situations.

after carrying out palpitory method, deflate the cuff.

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auscultatory method

now the main aim of the BP station - to measure the systolic and diastolic pressure.

this method involves-

1. put stethoscope into your ear.
2. put diaphragm onto the radial pulse. (you will not hear anything YET)
3. inflate the cuff until your estimated systolic blood pressure + 20Hg.
4. deflate cuff slowly, untill karatkoff sound 1 is heard.
5. continue deflating slowly, untill karatkoff sound 5 is heard

we are expected to know the 5 karatkoff sounds, and able to describe this to the examiner.

five types of Korotkoff sounds:

The first Korotkoff sound is the snapping sound first heard at the systolic pressure. Clear tapping, repetitive sounds for at least two consecutive beats is considered the systolic pressure.

1. 1. The first Korotkoff sound is the snapping sound first heard at the systolic pressure. Clear tapping, repetitive sounds for at least two consecutive beats is considered the systolic pressure.
   2. The second sounds are the murmurs heard for most of the area between the systolic and diastolic pressures.
   3. The third = A loud, crisp tapping sound.
   4. The fourth sound, at pressures within 10 mmHg above the diastolic blood pressure, were described as "thumping" and "muting".
   5. The fifth Korotkoff sound is silence as the cuff pressure drops below the diastolic blood pressure. The disappearance of sound is considered diastolic blood pressure -- two mm Hg above the last sound heard.

you take the 4th korotkoff sound as the diastolic pressure in pregnent mothers and small children. we don't know why, but we found that the 4th sound corresponds more to the diastolic pressure.

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after you have taken the patient's blood pressure, deflate the cuff, and report.

the Blood pressure of Mr ----- was -(systolic BP)- upon -(Diastolic BP)-.

update -

more complete way to say it would be;

The blood pressure of Mr/Mrs ----- is *sys BP* upon *dia BP* on the Right/Left Brachial artery, in seated / lying position.

You'll never go wrong this way, and you might even impress some people. - but if you're actually aiming for distinction, you gotta know why it matters that it is Right/Left, Seated or Lying.

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thank the patient, WASH HANDS, and leave.

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we should be able to finish this in 5 mins.

that will be the end of a normal blood-pressure taking station.

possible VIVA questions;

• what is a pulse pressure?
• SBP(systolic blood pressure) minus DBP (Diastolic Blood Pressure)
• what would raise the value of pulse pressure?
• aortic regurgitation, anxiety, exercise, atherosclerosis
• what would decrease the value of pulse pressure?
• hypovolemia, aortic stenosis, cardiac tamponade
• when would you use the 4th Korotkoff sound for diastolic pressure reading?
• pregnant mothers and small children
  *slightly obsolete and controvertial. now the common practice is just use 5th, if no 5th, use 4th - for more info... check out http://www.ncbi.nlm.nih.gov/pubmed/9737283 and other articles*

the above questions are actual past exam questions.

the below, are what I know (which means, its good to know when you're in sem5, fantastic if you know before that)

• what is the opimal, normal, high normal, mild hypertension, moderate hypertension and severe hypertension?
• optimal - <120 / <75
• normal - 120-129 / 75-84
• high normal - 130- 139 / 85-89 
• mild HTN - 140-159 / 90-99
• moderate HTN - 160-179 / 100-109
• severe HTN - >180 / >110
• when do you treat Hypertension?
• Everyone with BP >160/100, for those >140 / 90, it depends whether the patient have risks of coronary events, such as obesity, hyperlipidaemia, Diabetes etc. if there is/are, treat.
• rare but curable causes of Hypertension
• pheochromocytoma  - suspect if BP difficult to control via medication, accelerating, episodic, or patient is dying! - patient may develop Takotsubo cardiomyopathy (severe substernal pain - MI-like symptoms)
• Conn's Syndrome - measure serum Potassium level. if hypokalemia, look into this. - diagnose by renin/aldesterone ratio. (increased aldesterone suggests Conn's $) - do MRI abdomen if suggested Conn's.
• medications for hypertension
• Ca-channel blocker
• 1st choice in >55yrs or in any black patients
• nifedipine etc
• thiazide
• chlortalidone etc
• Ace-inhibitor
• 1st choice in <55yrs
• good to use with Ca-ch blocker or diuretics 
• hence good 2nd medication
• common SE - cough -> change to ARB *losartan, candesartan
• cardipril, lisinopril etc
• B-blockers
• bisoprolol
• "what if the patient has hypertension now, without document previous hypertension?"
• confirm hypertension by repeated blood pressure monitoring on a separate day. ideally, more than 2 consecutive days. 
• also, carry out investigations to assess end-organ damage such as;
• hypertensive retinopathy, LVH on ECG, Blood tests - serum creatinint, fasting glucose and lipids, urinalysis for albuminuria, proteinuria etc.
• rule out secondary causes if onset is early - young hypertensives warrant an extensive ruling out of secondary hypertension.