内科学呼吸衰竭课件.ppt

Respiratory failure Contents 0f outline Definition Etiology Pathogenesis Classification Clinical manifestations Diagnosis Treatment Introduction Be a frequently encountered medical problem A major cause of death in China Mortality from COPD, which ends in death from respiratory failure, continues to increase More than 70% of patients with pneumonia are attributed to respiratory failure About 1/3 patients in ICU in the United States, about 500 000 persons, receive mechanical ventilation each year Introduction (cont.) Short-term survival is more than 80% for acute respiratory failure not preceded by additional lung disease or systemic illness Multi-system organ failure or pre-existing renal, liver, or chronic gastrointestinal disease with malnutrition substantially worsens outlook About 17% of patients placed on mechanical ventilation require assistance for more than 14 days Among those requiring this amount of mechanical ventilation, elderly patients have a 9% survival and younger patients a 36% survival Definition Be a clinical syndrome of respiratory and metabolism dysfunction caused by any condition that severely affects the lung’s ability to maintain arterial oxygenation or carbon dioxide elimination. Both acute or chronic respiratory failure may be divided into two main categories. A failure of gas exchange – hypoxemia A failure of ventilation – hypercapnia Classification According to pathophysiology and arterial blood gas analysis: Type I: A failure of gas exchange Hypoxemia, PaO2 60 mmHg Type II: A failure of ventilation PaO2 60 mmHg, PaCO2 50 mmHg PaO2 60 mmHg, PaCO2 50 mmHg Iatrogenic Classification According to the involved site Central respiratory failure Change of respiratory rhythm and frequency Peripheral respiratory failure Dyspnea According to onset of respiratory failure Acute, develops in seconds or hours Chronic, develops in days or longer, elevated HCO3- Acute onset of Chronic respiratory failure Have no definitive borderline Acco