THORACIC AND RESPIRATORY
DISORDERS
SPONTANEOUS AND IATROGENIC PNEUMOTHORAX
Pneumothorax is defined as the presence of air in the pleural space.
■ Spontaneous pneumothorax:Not caused by any obvious external factor
(eg, trauma)
■ 1 °spontaneous pneumothorax: No clinically apparent lung disease;
usually tall, thin males
■ 2 °spontaneous pneumothorax:Occurring in patients with underlying
pulmonary disease process (see Table 10.18)
■ Iatrogenic pneumothorax: The result of diagnostic (thoracentesis) or ther-
apeutic intervention (central venous catheter placement)
SYMPTOMS/EXAM
■ Most patients present with unilateral chest pain (either sharp or steady
pressure) and acute shortness of breath.
■ Patients with significant underlying lung disease may present with signifi-
cant distress, even with a small pneumothorax.
TABLE 10.17. Exudative Pleural Fluid Analysis and Interpretation
PLEURALFLUIDTEST INTERPRETATION
RBC count Grossly bloody or >100,000 cells/mm^3 suggests trauma,
malignancy, PE, pneumonia
Neutrophils >50% suggests acute pleural process (infection, PE).
Lymphocytes >50% suggests chronic pleural process (TB, malignancy)
Eosinophils Presence suggests air or blood in pleural space.
Glucose <60 mg/dL suggests a complicated parapneumonic effusion,
malignancy, ruptured esophagus, TB, or rheumatoid arthritis.
Triglycerides >110 mg/dL suggests chylothorax.
pH Pleural pH <7.2 with parapneumonic effusion indicates the
need for drainage.
TABLE 10.18. Common Causes of Secondary Spontaneous Pneumothorax
COPD (most common)
Asthma
Pneumonia (eg, PCP)
TB
Interstitial lung disease
Cystic fibrosis
Malignancy
Endometriosis