Dorothy FarrarBodyplethysmographie
Body plethysmography is used to examine patients who suffer from respiratory diseases or have received a suspected diagnosis in this regard. In addition, the diagnostic procedure is used in the context of sports medicine and preventive examinations. The results achieved are compared with normal values - based on age, gender and height – and evaluated.
What is a body plethysmography?
Body plethysmography determines how well the patient ‘s lungs are working. The whole body examination is also referred to as a “large lung function test” (LuFu). The exact lung volume and airway resistance are determined as part of the extensive lung function test.
To do this, the patient must stay in an airtight chamber for a while and breathe in and out through a special mouthpiece.
Various values are determined in body plethysmography. At the same time, the electronically measured values are graphically displayed in a pressure-volume diagram, called a breathing loop, which shows exactly which respiratory disease the patient is suffering from: each of them has its characteristic “pattern”.
Application and function
Body plethysmography is used by the pulmonologist to differentiate between obstructive and restrictive lung diseases and to determine their respective severity. With their help, he can also determine exactly which lung disease his patient has.
Among the diseases that occur most frequently in the pulmonary specialist practice are obstructive disorders, which are caused by the narrowing of the upper airways. In order to diagnose it, the patient has to breathe against an increased resistance (closed mouthpiece). For example, patients with bronchial asthma , chronic bronchitis and COPD (chronic obstructive pulmonary disease) have below-average FEV1 values because the narrowed bronchi impede the flow of air.
RV values are also elevated in asthma and pulmonary emphysema . Areas of application of the procedure for obstructive airway diseases are shortness of breath , coughing , chronic bronchitis or COPD, pulmonary emphysema, bronchial asthma and difficult breathing due to foreign bodies, increased mucus formation and airway tumors.
The restrictive lung diseases are caused, for example, by reduced elasticity of the lungs during breathing. It can arise as a result of pulmonary fibrosis , pleural effusion and diaphragm elevation and shows itself, for example, as a too low VC value.
In addition, the extensive lung function test is carried out in addition to observing the course of the disease, monitoring the treatment, diagnosing allergies and carrying out bronchospasmolysis tests.
methods and procedures
The body plethysmography determines the following parameters: R (flow resistance in the airways, maximum 0.35 kPa/l/s), tidal volume with normal inhalation and exhalation (AV, approx. 0.5 liters), inspiratory reserve volume (IRV, Amount of air that can be additionally taken in after normal inhalation, about 3 liters), expiratory reserve volume (ERV, amount of air that can still be expelled after normal exhalation, about 3.5 liters).
As well as vital capacity (VC, the maximum amount of air that can be exhaled after a strong inhalation, 3 to 5 liters), one-second capacity (FEV1, same procedure as for VC but limited to 1 second, at least 70%), residual volume (RV, amount of air, which is still present in the lungs after a strong exhalation, about 1.3 litres). Sometimes the whole-body plethysmography is supplemented by an additional measurement of the oxygen diffusion capacity.
It is performed using a separate device filled with a harmless amount of carbon monoxide, which the patient must inhale.
What does the patient have to consider?
Patients undergoing body plethysmography do not need to make any special preparations. Therefore, the examination is also suitable for people with limited capacity to act and for children. Compared to normal spirometry, it is ideal for patients who are hardly able to consciously inhale and exhale more.
The measurement results are more accurate because they cannot be influenced by the patient’s possibly incorrect cooperation. In contrast to the normal lung function test (spirometry), which is also carried out in family doctor’s surgeries, the patient can only have the body plethysmography carried out by a pneumologist or in a hospital.
Patients who regularly have to take bronchodilator medication should point this out to the lung specialist in the preliminary medical consultation. You will be dropped off at short notice before the big LuFu.
process and implementation
The patient sits on a chair in a 1 square meter airtight, telephone booth-like booth. His nostrils are closed with a nose clip to prevent him from accidentally inhaling and exhaling through his nose. Then he breathes in and out according to the audible instructions through a special mouthpiece or holds his breath for a short time.
The sensors installed in the cabin measure the air volume and pressure changes within the room that occur when you breathe and use these values as normal values. They are the counterpart to the changes in air volume and pressure that prevail in the air sacs of the breather.
The airway resistance and other parameters can be precisely determined from the values measured via the mouthpiece. The air flow is shown in the form of a special diagram, based on the typical course of which the pulmonologist can determine which disease the patient has.
The residual volume RV is calculated from the difference between ITVG and ERV. The intrathoracic gas volume (ITVG) is determined by automatically closing the patient’s mouthpiece for a short time at the end of exhalation and having the patient breathe against it for at least 6 seconds. The resulting closure curve makes it possible to determine the volume of air still in the lungs when exhaling. Forced breathing against resistance is used to determine the ERV value.
Self-service or health insurance – who will bear the costs?
The costs for body plethysmography are covered by statutory health insurance if the examination is medically necessary. As a sport and check-up, it is considered an individual health service (IGeL) and must be financed by the patient himself.
Risks, dangers and complications
Whole-body plethysmography usually does not lead to any health complications. Therefore, even small children are examined with her. In individual cases, however, unforeseeable incidents can occur depending on the severity of the respiratory disease and any other diseases that the patient may have. The use of anti-obstructive medication may also be necessary in an emergency. Individuals with hypercapnia, hypoxemia, acute respiratory infection, recent heart attack , cardiac arrhythmia , coronary artery disease , aneurysm , epilepsy , and severe hypertensionand pregnant women should not undergo the examination if possible.
Hello and welcome to my Health Guide & Encyclopedia! My name is Dorothy Farrar, and I'm the founder and main author of this platform.
My passion for health and wellness started at a young age when I became interested in the connection between the food we eat and the way we feel. This fascination led me to study nutrition and dietetics in college, where I learned about the importance of a balanced diet and the impact of various nutrients on the body.