[Indications for and limitations of the exercise tests in respiratory physiopathology]

Following a review of the physiology of the subject, attention is concentrated on the significance of O2 consumption during exercise. The stages through which O2 passes prior to being used by the muscles are discussed, i.e. respiratory, cardiocirculatory, haematic, metabolic-tissue stages. Subsequently, the methods most commonly employed to evaluate the capacity of a patient to withstand an exercise test are illustrated and discussed. The various types of ergometers are covered first, the positive and negative features of each being indicated. The various tests are then described, these being subdivided according to their intensity into maximal and submaximal tests and, according to the load, into tests with constant load, increasing load, continuously growing load and variable load. The salient features of each are listed. The measurements (parameters, units, indices) that may be used and the standards to be observed on the basis of W.H.O. and EEC proposals are considered. After presenting the factors on the basis of which an exercise test may be appraised in relation to its purposes, the criteria for interpreting results in healthy and sick subjects are examined, with particular attention being paid to pneumo-patients and those with heart diseases. Particular stress is laid on the variations in certain basic parameters, such as Maximum withstandable effort, Oxygen debt, Maximum aerobic work, Ventilation break point and the behaviour of Haemogasanalytic, ECG, Cardiac output and Pulmonary artery pressure data in normal and pathological situations.