IRV refers to the extra volume of air that can be inspired above VT. It can help evaluate restrictive lung conditions. Mathematically, it is subtracting the VT from the IC (see Figure 14.1).
Have the patient either sit or stand. Place nose clips on the nose and instruct the patient to breathe normally through a mouthpiece/filter (bacterial/viral) combination into the spirometer.
After several breaths, ask the patient to inhale maximally, expanding the lungs as much as possible from end-tidal expiration. Have the patient resume normal breathing.
Repeat step 2 two or more times until the two best values are within 5% of each other. Select the largest inspired volume value.
Pretest Patient Care
Instruct the patient about the purpose and procedure of the test and the need for patient cooperation.
Follow guidelines in Chapter 1 for safe, effective, informed pretest care.
Posttest Patient Care
Review test results; report and record findings. Modify the nursing care plan as needed.
Follow guidelines in Chapter 1 for safe, effective, informed posttest care.