Back to Basics: How To Take Blood Pressure Manually

Say it with me out loud: “Sphygmomanometer.” OK, that’s not fair — let’s try it slower: “sfig·mow·muh·naa·muh·tr.”¹ Nothing like a tongue twister on your first day in the nursing skills lab! But don’t worry if you can’t pronounce the name of the device. Learning how to take blood pressure manually is a more important skill than knowing how to say it.

In This Article:

• What Is Manual Blood Pressure?
• How To Use a Manual Blood Pressure Cuff
• How To Take Manual Blood Pressure
• What Do Blood Pressure Numbers Tell Us About Our Patients?
• Why Choose a Manual Blood Pressure Over a Digital Reading?
• Take the Pressure Off: For Manual Blood Pressure Measurements

What Is Manual Blood Pressure?

Modern blood pressure readings are most often taken by a blood pressure machine, or sometimes through a device placed in the patient's artery, called an arterial line, that can measure blood pressure continuously.² (This is often used in the intensive care unit or in emergency situations.) Unlike an electronic or digital blood pressure machine, manual blood pressure uses simpler tools to measure and calculate a patient’s blood pressure.

An Austrian Jewish physician, Samuel Siegfried Karl Ritter von Basch, invented the sphygmomanometer in 1881 to measure the amount of pressure inside the blood vessels of the human body. In 1901, Dr. Harvey Cushing brought the device to the United States and modernized it, after which the tool began gaining popularity among physicians.³

To check manual blood pressure, you will need these items:

• Sphygmomanometer, which includes an inflatable arm cuff
• Pressure valve
• Gauge device
• Stethoscope

Rarely will you need to take manual blood pressure, but it is a skill you should and will have to learn in case you don’t have a blood pressure machine, or if the machine is inaccurate.

How To Use a Manual Blood Pressure Cuff

When beginning a manual blood pressure check, first and foremost, check whether the patient has any arm restrictions. Some patients, such as those with dialysis fistulas, long-term vascular devices, breast removal, or a newly placed pacemaker, should not have their blood pressure checked on the same arm. Ask the patient or caregiver and look for a medical alert bracelet for confirmation.

Blood pressure cuffs come in different sizes, regardless of whether they are used to take a manual or electronic blood pressure reading. Choosing the right size is important because the wrong size can yield incorrect results — anywhere from 5 to 20 mmHg difference.⁴ Recording a patient's blood pressure as being higher or lower can lead to medical errors if medications that affect blood pressure are not given properly.

Once the proper-sized cuff is on the patient, connect the tube to the hand pump. Be sure not to over-inflate the cuff, because doing so can cause inaccurate readings, or worse — damage to the patient's skin and vasculature.

How To Take Manual Blood Pressure

Now that you know what a sphygmomanometer is, and the equipment you need to manually check blood pressure, let's learn the manual blood pressure steps and how to take manual blood pressure readings accurately.⁴

Manual Blood Pressure Steps:

1. Instruct your patient to sit quietly for three to five minutes with their legs uncrossed to let their blood pressure normalize.

2. Place the cuff around the upper arm, one inch above the elbow.

3. With your non-dominant hand, place your stethoscope on the inside of the arm, with a portion of the bell under the cuff over the brachial artery (in the bend of the elbow), and insert your earpieces (you might not hear a heartbeat yet, but just wait).

4. Rest the sphygmomanometer gauge where you can see the numbers, and place your dominant hand around the pump.

5. When you are ready, close the valve on the pump, and begin to squeeze the pump quickly to inflate the cuff.

6. Listen. At first you may not hear a pulse beat. This is normal, but as the cuff inflates, you will begin to hear the first pulse sounds. Give a gentle squeeze — no more than 30 mmHg above the patient’s normal systolic blood pressure or where the radial pulse (between the wrist bone and tendon on the thumb side of the wrist) disappears.

7. Take your reading. Slowly release the valve while you continue to listen to the brachial artery pulse. When you hear start to hear the pulse, you have reached your systolic pressure. Read the gauge and remember this number. As the cuff continues to deflate, the pulse sound may soften, so listen closely. Once the pulse sound stops, you have reached your diastolic pressure. Read the gauge and remember this second number.

If you had trouble hearing the pulse sounds, don’t worry. Wait three to five minutes to let your patient rest before checking again. If it is safe to do so, you can try to check using the opposite arm. If you still cannot assess the patient’s blood pressure manually, don’t be afraid to ask a colleague for help.

What Do Blood Pressure Numbers Tell Us About Our Patients?

Blood pressure readings consist of three numbers: systolic, diastolic and mean. The first two are the numbers you hear when auscultating a manual blood pressure, and the third is a calculated average to determine the mean) value:⁵

Normal Blood Pressure Reading for an Adult: Less than 120/80

Mean Blood Pressure = diastolic blood pressure (DBP) + 1/3 [systolic blood pressure (SBP) – DBP]

Example: DBP = 65 and SBP = 120

MBP = 65 + ⅓ of (120) = 65 + 40 = 105

Blood pressure readings tell us a lot about our patients, including how much stress is on the heart. For example, if a patient’s blood pressure is too high, they may have a headache or it may mean that something else is not right in their body. If their blood pressure is too low, the patient may feel dizzy or weak; this could be a sign of dehydration, or worse — that they are losing blood.

Why Choose a Manual Blood Pressure Over a Digital Reading?

There are some situations where checking a manual blood pressure is preferable to using a digital or electronic blood pressure machine. For example, if all you have is an old-fashioned sphygmomanometer and a stethoscope, a manual blood pressure check may be your only option. Another time a manual blood pressure may be necessary is if the patient's heart rate is too elevated or irregular, and the electronic machine cannot accurately assess the blood pressure.

Making sure that you are accurately recording blood pressure, whether manually or electronically, ensures that you are making the right clinical decisions to keep your patient safe.

Take the Pressure Off: For Manual Blood Pressure Measurements

Knowing how to take manual blood pressure readings, what the numbers you hear mean, and what blood pressure readings are normal or abnormal, is a foundational nursing skill. Proficiency in this skill carries over to your proficiency in other nursing skills. Now that you know how to take blood pressure manually, you can take the pressure off yourself to learn how to pronounce “sphygmomanometer.”

Your nursing school clinicals, as part of Grand Canyon University’s nursing degree program, are an opportunity to practice taking manual blood pressure and other vital nursing skills. Begin your nursing career with GCU’s accelerated BSN program, where you can earn your BSN degree in as few as 16 months.⁶ Complete the form on this page to connect with a university counselor.