Wet Spirometer Directions

A wet spirometer is a medical device used to measure the maximum amount of air a person can exhale, which is known as vital capacity. The wet spirometer has a breathing tube attached to a chamber inside the machine that is suspended in water. When the patient breathes into the tube, the chamber rises. How much it rises depends on the volume of air. Measuring vital capacity with a wet spirometer is easy, but you must follow the protocol accurately each time so you can determine whether a patient's health is improving or not.

Things You'll Need

• Wet spirometer

Show More

Instructions

• 1

  Ask the patient to sit, relax and breathe normally while you prepare the wet spirometer by attaching a disposable mouthpiece to the machine's valve.

• 2

  Clamp the patient's nose closed so he can only breathe through his mouth. Ask him to inhale normally and exhale into the mouthpiece. Record the volume displayed on the machine. This is the baseline measurement known as the tidal volume. It is the volume of air the patient exhales in a normal breath.

• 3

  Instruct your patient to take the deepest breath he possibly can and exhale into the tube. Try not to let any of the breath escape the tube or your reading won't be accurate. Record the volume displayed on the machine. This is the patient's vital capacity.

• 4

  Repeat the test and average the results.

• 5

  Compare the patient's vital capacity measurement to measurements taken at previous times to determine whether he is improving or not.