[Pathophysiology, diagnostics and treatment of the respiratory pump]

Diseases of the lung result in oxygen deficiency, hypoxemia, with the indications for oxygen supplementation, whereas hypercapnia and dyspnea are consequences of disorders and failure of the ventilatory pump, which need to be treated by mechanical ventilation. Early diagnostics enable a timely noninvasive ventilation treatment and can prevent overt ventilatory failure and avoid acute invasive ventilation. Diagnostic measures are available, so that the risk of developing overt respiratory failure can be ascertained in time. Treatment of respiratory pump insufficiency, i.e. ventilatory insufficiency, is also established. Many patients with ventilatory insufficiency use intermittent or continuous ventilation every day in order to relieve the respiratory musculature. Many studies have confirmed an extension of life expectancy and a better quality of life, when this relief together with a lowering of the pCO₂ is achieved under ventilation and more importantly while breathing spontaneously. If the target of lowering the pCO₂ is not achieved, an effect of intermittent ventilation cannot be detected. The more severe the disease, the more difficult it is to achieve relief, because the substantial effort needed for breathing by the patient can hardly be relieved by assisted ventilation alone. The relief is always guaranteed by a total passive mechanical ventilation below the apnea threshold so that the patient does not need to independently breathe. A high tidal volume, an adequately high respiratory rate and a prolonged inspiration time are necessary in order to reduce the pCO₂ to below the normal range and to induce passive ventilation. No lung damage has been observed with this treatment strategy in a large number of patients.