Ever wanted to learn how to take a blood pressure reading?
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Step 1: Intro:
Blood pressure is read as two numbers, usually written as ratio like 120/90. The systolic number(high number) measures the pressure inside the arteries as the heart contracts(beats), while the diastolic number(low number) measures the pressure as the heart rests(fills with blood between beats). Blood pressure is important to monitor regularly, especially in the elderly, to avoid living with hypertensive(high pressure) or hypotensive(low pressure) pressures, which can be deadly if left untreated over a long period of time. The normal range for a healthy individual should read 120-140 systolic pressure and between 70-90 diastolic pressure.
Step 2: Items Required:
- Manual Blood Pressure Cuff
- Alcohol Wipes
- Pen and Paper
Step 3: Getting to Know the Instruments: Stethoscope
A stethoscope(instrument for used for listening to someone's internal organs) has two ear pieces and a disk-shaped resonator. The resonator picks up sounds inside the body and transfers the sound waves through the cords to the ear pieces. It allows the user to listen as blood passes through arteries when the heart beats. Sounds will have a characteristic, "tothump, tothump, tothump" which lasts for about 30 seconds.
Step 4: Manual Blood Pressure Cuff
A manual blood pressure cuff is attached around the arm of the person, around the bicep area. You can securely strap it by securing the velcro adhesive ends. There are two cords coming out of the strap, the gauge which measures in 20 increments, each line counts as 2 mm Hg(milliliters of Mercury). It reads from 0 to 300 mm Hg. The other cord has an air pump with a valve to lets you turn it on/off. The pump is used with one hand, with the valve closed, it inflates the strap on the arm, cutting circulation of blood. Usually it is pumped up until the needle reads 160 mm Hg, then the valve is opened up to let the strap deflate, allowing for blood flow inside the arteries. With the stethoscope located next to the cuff(strap), sounds are picked up as blood rushes with pressure with each heartbeat.
Step 5: Alcohol Wipes
Alcohol wipes are used for cleaning the surfaces of the instruments prior and after each use. It is a good practice of hygiene. They also help clean oils or dirt, which can easily provoke rashes and other skin infections.
Step 6: Pen and Paper
Equally important are the pen and paper, even though it may not seem like they are. Sometimes there is so much going on at the same time, and people lose track of the readings they got. For example, after a person finishes measuring the BP(blood pressure), he/she might make a mental note and doesn't write it down immediately, which could cause for the number to be forgotten, because then the person expects to remember it, so he/she takes the cuff off from the arm and then puts the instruments away. Then trying to remember the number you took 10 seconds ago might be difficult. So a new blood pressure reading will be taken and the person having the cuff inflated on might not like the idea, as it causes discomfort when the cuff is choking the arm. So, as soon as you are done taking the BP, write it down.
Step 7: Required Steps:
- clean stethoscope's ear pieces and disk-shaped resonator with alcohol wipes.
- wipe inner cuff's surface.
- have pen and paper near by.
Step 8: Close Air Valve
- right turn the air valve(located at the top of the hand pump) all the way tight.
Step 9: Attach Cuff
- ask the person to lift up his/her sleeve all the way so that there is no clothing around the bicep area.
- extend arm of person horizontally, it is easier to have the arm resting on a flat surface.
- find and feel for a pulse with two fingers on the brachial artery(located where the forearm meet the bicep) right above the elbow.
- the inner cuff has a sign that reads "artery here", place it on top of the artery who's pulse you felt with your fingers.
- secure cuff on arm, not too tight or too lose.
Step 10: Prepare Stethoscope
insert earpieces so they sit comfortably inside the ears.
grab disk-shaped resonator and make a sound check, tap with a finger the resonator surface until you hear the sound coming back.
- place resonator next to pulsating artery and hold it in place.
Step 11: Inflate/Deflate Cuff
- inform the person that the cuff will begin to inflate, creating a temporary pressure sensation.
- squeeze the pump,air will flow into the cuff. The other hand will hold the stethoscope's resonator in place.
- notice how the needle moves up the gauge while you squeeze the hand pump.
- do not pump past 160 mm Hg as this is very painful on the receiving arm.
- when the arm is at 140 mm Hg turn the valve one-eight of a turn to the left, to let some air escape and start deflating the cuff.
Step 12: Listen for the High Number
When the needle is pointing at 140 mm Hg there will be no blood coming through that brachial artery, therefore there will be no sound, because the artery will be pressed flat from the pressure that the cuff exerts on the arm.
- When the valve is opened 1/8 of a turn to the left, the needle starts coming back towards 0 mm Hg.
- Then, the needle will start oscillating (going back and forth).
- The artery is filling with blood once again at this point.
- You will hear the first sound, "tothump, tothump, tothump", as the needle keeps dropping.
- Record the number on the gauge, when the first sound is heard, where ever the needle was at that point, that is the systolic (high) number.
Step 13: Listen for the Low Numbert
- As the needle keeps dropping the sound will become faint.
- Record the number on the gauge, when there is no sound, this reading will tell the diastolic(low) number.
- Turn the valve all the way to the left at this point.
Step 14: Remove Equipment
- Remove strap from arm.
- Take the earpieces from you ears and resonator from the arm.
- Wipe down earpieces and resonator surface.
- Wipe inside of BP cuff and roll all the way.
- Thank the person!
Step 15: Keep Practicing!
Now that you know how to take a BP reading, you can practice on tomato cans, soda bottles, and the like to get a feel for how to tighten the strap around and how to inflate it with the hand pump, as well as the air valve since it's very sensitive, and can cause the needle to drop fast and provide with an inaccurate reading. Seek medical help if your blood pressure in above 140 for the high number and above 90 for the low number, as they may indicate high blood pressure.