——Current Medical Diagnosis and Treatment
這一部分最後一個病。沒有新詞，有一些我記得不太熟的標了中文，其它標紅的重點詞彙以前都學過，看你記得幾個吧。
D49 Pulmonary Disorders 之 Acute Respiratory Distress Syndrome
General Considerations (略）
這部分太多下標了，我仍然沒找到google doc 裡的下標在哪兒，略了～
Clinical Findings
ARDS is marked by the rapid onset of profound dyspnea that usually occurs 12-48 hours after the initiating event. Labored breathing, tachypnea, intercostal retractions, and crackles are noted on physical examination. Chest radiography shows diffuse or patchy bilateral infiltrates that rapidly become confluent; these characteristically spare the costophrenic angles（肋膈角）. Air bronchograms支氣管造影 occur in about 80% of cases. Heart size is usually normal, and pleural effusions are small or nonexistent. Marked hypoxemia occurs that is refractory to treatment with supplemental oxygen. Many patients with ARDS demonstrate multiple organ failure, particularly involving the kidneys, liver, gut, central nervous system, and cardiovascular system.
Differential Diagnosis
Since ARDS is a physiologic and radiographic syndrome rather than a specific disease, the concept of differential diagnosis does not strictly apply. Normal-permeability ("cardiogenic心原性的" or hydrostatic) pulmonary edema must be excluded, however, because specific therapy is available for that disorder. Emergent echocardiogram or measurement of pulmonary capillary wedge pressure 肺毛細血管楔壓 by means of a flow directed pulmonary artery catheter may be required in selected patients with suspected cardiac dysfunction; rou tine use in ARDS is discouraged.
Prevention
No measures that effectively prevent ARDS have been identified; specifically, prophylactic 預防性的 use of PEEP in patients at risk for ARDS has not been shown to be effective. Intravenous methylprednisolone does not prevent ARDS when given early to patients with sepsis syndrome or septic shock.
Treatment （略）
Course & Prognosis
Overall, ARDS mortality with low tidal volume ventilation is around 30% in ARDSnet studies. The major causes of death are the primary illness and secondary complications, such as multiple organ system failure or sepsis. Many patients who die of ARDS and its complications die after withdrawal of mechanical ventilation. One troubling aspect of ARDS care is that the actual mortality of ARDS in community hospitals continues to be higher than at academic hospitals. This may reflect the fact that a significant number of community hospital-based clinicians have not adopted low lung volume ventilation.
Different clinical syndromes that lead to ARDS carry different prognoses. For example, patients with trauma associated ARDS have better prognosis, with a mortality rate close to 20%, whereas those with end-stage liver disease have an 80% mortality rate. This presumably reflects the effect of significant comorbidities (trauma patients tend to be younger and healthier) but may also represent different types/severities of inflammation associated with different precipitants of ARDS.
Failure to improve in the first week of treatment is a poor prognostic sign. Survivors tend to be young and pulmonary function generally recovers over 6-12 months, although residual abnormalities often remain, including mild restrictive or obstructive defects, low diffusion capacity, and impaired gas exchange with exercise. Survivors of ARDS also have diminished health-related and pulmonary disease-specific quality of life as well as systemic effects, such as muscle wasting, weakness, and fatigue.
以上來自Current Medical Diagnosis and Treatment，版權屬原作者。