Читать книгу Emergency Medical Services - Группа авторов - Страница 169

Oxygenation and ventilation are distinctly different but interrelated physiological processes. In general, adequate oxygenation requires sufficient ventilation to deliver gas to alveolar spaces, where oxygen can then enter pulmonary capillaries for transport to peripheral tissues. Pulse oximetry is a useful tool, except in cases of carbon monoxide poisoning, to help determine the extent of tissue oxygenation. Patients with respiratory distress or SpO₂ less than 94% should receive supplemental oxygen. However, use of oxygen should not be indiscriminate.

Ventilation is about gas moving in and out of the lungs. Clearly, it can occur without oxygen, and, in that sense, is a distinct process. The adequacy of ventilation is generally assessed in terms of minute ventilation. Waveform capnography is a useful tool to both monitor ventilation and evaluate its effectiveness. NIPPV may provide needed support to an awake patient with inadequate ventilation but intact respiratory drive. Mechanical ventilation is the maximum ventilatory support tool. Especially in a dynamic prehospital environment, vigilant monitoring is imperative to promptly identify and address deficiencies in ventilation and oxygenation and complications arising from their treatment.