FAQ

Spirometry

Why Spirometry?

A spirometry is done to assess the respiratory function. This test should be done routinely by General Practitioners as it is the most sensitive test to detect Chronic Obstructive Pulmonary Disease (COPD), a very common and possibly lethal disease caused mainly by smoking.

The most important test is the "forced vital capacity" (FVC), which gives some very important parameters of the lung function, like the "forced expiratory volume during the first second" (FEV1), the Peak (Expiratory) Flow (PEF) and the FEF25-75 and other "forced expiratory flow"- measurements like FEF75%, FEF50%, FEF25%, FIF50% and PIF.
During the FVC-manoeuvre, the physician should be able to see the flow-volume curve on a screen.
Other tests that can be done with a spirometer are the "maximum voluntary ventilation" (MVV) and the "(slow) Vital Capacity" (VC).

What are the indications for a spirometry?

The indications for spirometry include the need to

  • detect the presence or absence of lung dysfunction suggested by history or physical signs and symptoms (eg, age, smoking history, family history of lung disease, cough, dyspnea, wheezing) and/or the presence of other abnormal diagnostic tests (eg, chest radiograph, arterial blood gas analysis);
  • quantify the severity of known lung disease;
  • assess the change in lung function over time or following administration of or change in therapy;
  • assess the potential effects or response to environmental or occupational exposure;
  • assess the risk for surgical procedures known to affect lung function;
  • assess impairment and/or disability (eg, for rehabilitation, legal reasons, military).

AARC Clinical Practice Guideline - Spirometry, 1996 Update

What are the contraindications for a spirometry?

The requesting physician should be made aware that the circumstances listed in this section could affect the reliability of spirometry measurements. In addition, forced expiratory maneuvers may aggravate these conditions, which may make test postponement necessary until the medical condition(s) resolve(s).

Relative contraindications to performing spirometry are

  • hemoptysis of unknown origin (forced expiratory maneuver may aggravate the underlying condition);
    pneumothorax;
  • unstable cardiovascular status (forced expiratory maneuver may worsen angina or cause changes in blood pressure) or recent myocardial infarction or pulmonary embolus;
  • thoracic, abdominal, or cerebral aneurysms (danger of rupture due to increased thoracic pressure);
    recent eye surgery (eg, cataract);
  • presence of an acute disease process that might interfere with test performance (eg, nausea, vomiting);
  • recent surgery of thorax or abdomen.

AARC Clinical Practice Guideline - Spirometry, 1996 Update

What are the hazards and complications of a spirometry?

 

Although spirometry is a safe procedure, untoward reactions may occur, and the value of the information anticipated from spirometry should be weighed against potential hazards. The following have been reported anecdotally:

  • pneumothorax;
  • increased intracranial pressure;
  • syncope, dizziness, light-headedness;
  • chest pain;
  • paroxysmal coughing;
  • contraction of nosocomial infections;
  • oxygen desaturation due to interruption of oxygen therapy;
  • bronchospasm.

AARC Clinical Practice Guideline - Spirometry, 1996 Update

How can I detect exercise induces bronchospasm?

 

The "Exercise Challenge Test" identifiesa patient with Exercise Induced Bronchospasm.

Procedure:

  • Spirometry
  • 6-8 min practise at 70-80% of maximum pulsrate
  • 2nd spirometry

A decline of 15% or more is diagnostic for EIB

More information on spirometry.