We were talking about medical emergencies in dental clinic. We have seen role of team in emergency, ABCD of primary survey, recovery position, medical equipments like pulse oximeter, oxygen cylinder, mask, etc. till now.
Today we will talk about BP Machine in medical emergency equipment.
The routine work that we do in a dental clinic; the most unreliable and incorrect method is of BP measurement.
So, before learning BP measurement, let’s revise some of our basics.
SYSTOLIC BLOOD PRESSURE – When heart pumps the blood from ventricular systole to artery then the peak blood pressure of artery is known as systolic blood pressure.
DIASTOLIC BLOOD PRESSURE – when blood fills in the heart at the time of ventricular diastole, the blood pressure of artery goes down and this is known as diastolic blood pressure.
KOROTKOFF SOUNDS
We can hear five different sounds when BP cuff releases –
Phase 1 – A thud.
Phase 2 – A bowling or swishing noise.
Phase 3 – A softer thud than in sound 1.
Phase 4 – A disappearing bowling noise.
Phase 5 –
But practically systolic pressure is that when you can listen to the sound and diastolic pressure is that when you can’t listen to the sound.
Now, BP should be measured on which arm.
Ideally we should measure it on both the arms three times continuously but we don’t have that much time so we measure it on the right arm.
Now, let’s see the actual procedure.
BP measurement can be done by two devices.
Manual mercury sphygmomanometer.
Electronic BP machine.
At first let’s see manual measurement of blood pressure.
Traditional sphygmomanometer which works on auscultation method is popular till now also.
It is very reliable also if it is used in good way.
ACTUAL PROCEDURE-
First of all check instrument is working or not.
Second rotate knots to right to close it.
Now remove clothes from the arms of patients.
During the measurement of BP, it is very necessary that there should not be tight clothing on the arm that can restrict the blood flow.
The arm of the patient should be supported and be kept on the heart level only.
If the arm is not supported then BP will be very high and if the level of the arm is above the heart then BP will be low.
Ideally, cuff should cover 80% of the patient’s arm.
Cuff should be snugly fit; it should not be very tight.
We have to measure BP on the dental chair only during emergency and it is very tough to support arm, handle apparatus.
Now palpate brachial artery.
Now, gently keep the diaphragm of stethoscope on brachial artery.
Remember you neither have to apply much pressure nor stethoscope has to enter inside the cuff.
Now, inflate the cuff.
Normally, inflates until mercury reach from 200 to 220.
Now, open the value.
Slowly, deflate the cuff approx 2-3mm/s.
Note first sound appears and when sound disappears.
There are chances of error in manual method. Like –defective equipment e.g. leaky tube or faulty value.
Mercury is not initially on zero.
Hurl the air quickly.
Incorrect cuff size, either big or small.
Cuff is not on the same level of the heart.
Failure to observe mercury or poor technique.
Now, let’s talk about automated BP devices.
When automated devices came at first, it was questioned on its accuracy. But as the technology became advance these devices became better.
Nowadays these devices work in such manner.
Oscillometry to detect arterial blood flow. Most of the devices work on this principle only.
A microphone to detect korotkoff sound.
Ultrasound to detect blood flow.