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  • • Assessment of pulmonary function in patients with respiratory complaints.


  • • Pneumothorax.

    • Hemoptysis.


  • • Age; patients can usually perform maneuver starting between ages 4 and 5 years.

  • • Spirometer.

    • Individual mouthpieces.

    • Nose clips.

  • • Pneumothorax (rare).

  • • Adequate height, as measured with a stadiometer, is crucial to ensure utilization of appropriate predicted values.

    • A positive response to bronchodilator testing is defined as a 12% increase in the forced expiratory volume in 1 second (FEV1).

  • • Explain the procedure in a developmentally appropriate manner before and during procedure.

    • Coach the patient for optimal effort to ensure acceptable results.

    • In older patients, it is ideal to recommend no smoking for 24 hours prior to testing.

    • If assessing response to a bronchodilator, any bronchodilator medications should not be used for at least 8 hours before testing.

  • • Patient should be sitting upright or standing tall.

  • • Place nose clips on patient.

    • Patient makes a seal with lips around mouthpiece.

    • Ensure tongue does not block opening.

    • Have the patient breathe comfortably for 3 breaths (tidal breathing).

    • At end exhalation, have patient take fast breath in to fill lungs completely (to total lung capacity).

    • At top of inspiration, have patient exhale fast and hard and keep exhaling for 6 seconds or until flow plateaus.

    • At end of exhalation, inhale to fill lungs completely (total lung capacity).

    • Maneuver should be repeated to obtain 3 tests that are acceptable and reproducible.

  • • A test must first be considered acceptable and reproducible.

    • A test is acceptable if it fulfills the following criteria:

    • • No cough or glottic closure in first second of exhalation.

      • No leaks or obstruction of mouthpiece.

      • Adequate start of test without hesitation.

      • Full exhalation of 6 seconds or until plateau of volume.

      • No early termination of test.

    • Reproducibility in children can be defined as the values of the forced vital capacity (FVC) and FEV1 being within 5% on 3 acceptable maneuvers.

    • Obstructive lung disease is determined by a combination of the following:

    • • Decreased flows (FEV1, FVC, mid-range flows).

      • Scooped appearance to the flow volume curve (Figure 19–1).

    • • Decreased FEV1/FVC ratio.

    • Restrictive lung disease is suggested by a decreased FEV1 and FVC and a normal or decreased FEV1/FVC ratio (see Figure 19–1).

    • In order to adequately determine restrictive lung disease, full pulmonary function tests should be obtained to include lung volumes.

Figure 19–1.

Flow-volume loops showing normal pulmonary function as well as obstructive and restrictive lung disease.

  • • Spirometry alone may not give a complete assessment of the ...

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