The use of spirometry in the diagnosis of lung

Abstract

Spirometry is the measuring lung function, specifically the amount (volume) and/or speed (flow) of air that can be inhaled and exhaled. Spirometry may also be used periodically to check whether a treatment for a chronic lung condition is helping you breathe better. For this test, you breathe into a mouthpiece attached to a recording device (spirometer). The information collected by the spirometer may be printed out on a chart called a spirogram. Spirometry is generally a safe test. You may feel short of breath or dizzy for a moment after you perform the test. Key spirometry measurements include the following: • Forced vital capacity (FVC). This is the largest amount of air that you can forcefully exhale after breathing in as deeply as you can. A lower than normal FVC reading indicates restricted breathing. • Forced expiratory volume (FEV-1). This is how much air you can force from your lungs in one second. This reading helps your doctor assess the severity of your breathing problems. Lower FEV-1 readings indicate more significant obstruction. Indications for spirometry: Spirometer is an integral part of the evaluation, diagnosis and management of patients with respiratory disorders. The main indications are: • Evaluation a case with respiratory symptoms. • Assessment of severity of respiratory disorder. • Assessment of response to therapy. Per-operative evaluation of respiratory system. Contraindications for spirometry: Absolute contraindication for spirometry include recent myocardial infarction ie less than one month old. 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. Hazards and complications of spirometry: • Hazards of spirometry though rare include: • 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.