Spiroergometry, also known as ergospirometry, is a method that provides information about cardiac and pulmonary performance by measuring respiratory gases, at rest and during exercise. This method continuously measures the respiratory volume and the proportion of CO2 and O2 in the respiratory air and, derived from this, offers a wide range of information. For the correct measurement of the air volumes and the respiratory gases, the subject wears a face mask to which a volume sensor and also a suction tube are connected via which the determination of the composition of the respiratory gases in the spirometry device takes place. The most important measured values are the respiratory minute volume (AMV), the oxygen uptake, the carbon dioxide release and the respiratory rate.A number of special values can be derived from these. The respiratory quotient, the respiratory equivalent for oxygen, the respiratory equivalent for carbon dioxide, and the respiratory volume.
Indications (areas of application)
Spiroergometry is an important tool for the evaluation of shortness of breath (dyspnea) during physical exertion (exertional dyspnea). Heart and lung diseases can be the cause of shortness of breath, as can metabolic disorders or hormonal diseases.In healthy individuals, the method allows performance measurement, and in athletes, assessment of training status and performance progress. Spiroergometry allows the lungs and heart to be seen as a unit which is displayed under the conditions of metabolism. Spiroergometry thus provides information not only about the cardiovascular system and the lungs, but also about the musculature, the state of training, the skeletal and nervous systems, and cellular respiration. The method is excellently suited for assessing the lung function and cardiovascular function of sick people, e.g. before a major operation, and thus for better assessing the operation risk for the person in question. But not only sick people benefit from this method, many healthy people also use it to assess their training condition, to sound out performance reserves or to describe performance limits and to exclude health risks of sports. In recent years, spiroergometry has become increasingly important in both popular and competitive sports.
The procedure
Specifically, the method allows control of power intensity by measuring the anaerobic threshold (synonym: lactate threshold; denotes the highest possible load intensity that can just be provided while maintaining a state of equilibrium between the formation and breakdown of lactate) and the actual oxygen uptake, and additionally allows differentiation according to cardiological and pulmonological aspects. From the cardiac side, the heart rate and anaerobic threshold are of interest, as well as the oxygen pulse and CO2 concentration in relation to ventilation.From the pulmonological side, the measurement data of the respiratory reserve, the breathing patterns, the flow volume curve, and the estimation of a gas exchange disturbance are of interest.
NEUN fields graph
For those specifically interested, it should be noted that the wealth of data recorded during and after exercise on a treadmill or seated bicycle ergometer is processed by a computer and displayed via a NEUN-field graphic. Only this differentiated graphical representation makes it possible to distinguish in detail between cardiac and pulmonary factors or to show the complexity of the overall picture.
- The first field provides information on the achieved respiratory minute volume compared to individual target values.
- The second field provides information about the progression of heart rate over exercise time and oxygen pulse.
- The third field allows statements about the performance and also the cooperation.
- The fourth field provides a view diagnosis in terms of ventilation and metabolism, giving an indication of respiratory efficiency.
- The fifth field provides insight into the evolution of heart rate in relation to oxygen uptake, complementing the information from field two, it continues to provide information on the relationship between oxygen uptake and CO2 output, and thus on the aroben-anaerobic transition (anaerobic threshold).
- The sixth field shows the respiratory efficiency.
- In the field number seven can be seen as a visual diagnosis of the minute ventilation in relation to the respiratory volume and respiratory rate, and thus it allows an initial assessment of any respiratory disorder in terms of obstruction or restriction.
- The eighth field represents the gas exchange in the lungs, this provides information in about the workload and about the recovery phase.
- Field number nine is also intended for the consideration of the gas exchange, especially if in addition the values of the blood gas analysis are entered. From this, the values for the alveolar-arterial gas exchange as well as for the CO2 gas exchange can be read.
With the abundance of data obtained by spiroergometry, it must be remembered that the analysis of these data is very time consuming and is subject to a number of sources of error. Therefore, it is important to see the values in the context of the disease or the individual, for the benefit of the sick person and to correctly assess the performance capacity of the healthy person.
