Definition

• A very severe form of acute lung injury defined as a ratio of PaO2:FiO2<200mmHg in the presence of bilateral alveolar infiltrates on chest X- ray and in the absence of let ventricular failure.

Epidemiology

• Incidence rates range from 17 to 34 per 100 000 people years.

 • 10– 15% of all intensive care patients meet criteria for ARDS.

Aetiology

 • Any severe injury to the lung may lead to ARDS.

 • Common causes include severe pneumonia, shock, trauma, multiple transfusions. • In many cases, multiple factors act together

Pathogenesis

• Severe damage to the lung causes widespread alveolar necrosis with severe impairment of normal gas exchange.

Presentation

 • Severe breathlessness, in addition to signs of the underlying cause.

Macroscopy

• Both lungs are typically markedly heavy and fluid- filled, often weighing > 1000 g each (a normal lung weighs 300– 400 g).

Histopathology

• the histopathological hallmark is diffuse alveolar damage, characterized by the presence of hyaline membranes lining alveolar spaces.

• Hyaline membranes are composed of a mixture of fibrin and necrotic alveolar epithelial cells

Prognosis

 • Severe condition with high mortality rates averaging between 30% and 50%, depending on the cause.

 • Survivors usually demonstrate residual pulmonary functional abnormalities

مواضيع ذات صلة

Bronchiectasis

وسائط الالتهاب الحاد

قرحة الاثني عشري Duodenal Ulcer

Small bowel infarction

أمراض الخلية

الالتهاب الرئوي الفصي (ذات الرئة الفصية) (Lobar Pneumonia)

النوبة القلبية ( Heart attack )

التهاب القصبات الهوائية ( Bronchitis )

قرحة المعدة ( Peptic ulcer)

الامراض المشتركة Zoonosis

Zellweger Syndrome

XP) Xeroderma Pigmentosum)