How to Check Blood Pressure for Dehydration

A person becomes dehydrated when their body does not have enough water or fluids. If dehydrated, a person may experience a dry mouth, lips that are shriveled, infrequent urination, and lack of tears. Dehydration also causes low blood pressure readings. If you suspect that you or a loved one is suffering from dehydration, you can take your blood pressure for confirmation.

Things You'll Need

• Blood pressure monitor
• Stethoscope

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Instructions

• 1

  Roll up your sleeve, or remove your arm from your sleeve. It doesn't matter which arm you use, but to be consistent you should always use the same arm.

• 2

  Place your arm on a table and bend it slightly. Wrap the blood pressure cuff around your upper arm. You need the cuff to be at least one inch above your elbow.

• 3

  Locate a pulse in your arm below the cuff. A large artery is located on the opposite side of your elbow. Place your stethoscope on it. Put the earpiece of your stethoscope in your ears.

• 4

  Close the valve on the blood pressure monitor and completely inflate it. This will stop your blood from flowing temporarily.

• 5

  Open the valve and listen for the first pop or sound of blood flow. There is a numeric dial on the blood pressure monitor. You will see the arrow pointing at the numbers move up as you inflate the monitor. When you hear the first pop or sound of blood flow look to see which number the arrow on the blood pressure monitor is pointing to. This is your systolic measurement.

• 6

  Listen again for all sounds to disappear. Take a note of which number the arrow was pointing to when the sound disappeared. This is your diastolic measurement.

• 7

  Let the air out of the cuff and take it off. Put your shirt back on or roll your sleeve back down.

• 8

  Compare your blood pressure number with a normal blood pressure of 120 (systolic) over 80 (diastolic). If your numbers are lower than this, you may be suffering from dehydration. For example, a blood pressure reading of 90/60 can indicate dehydration. There are also other causes of low blood pressure such as heart disease, or taking certain medications. You will need to check with your doctor to find out if dehydration is definitely the cause.