Chronic Obstructive COPD is the greatest risk factor for the development of postoperative pulmonary com-Pulmonary Disease plications. COPD encompasses both chronic bronchitis and emphysema, disease entities that often occur in tandem. Cigarette smoke is implicated in the pathogenesis of both, and any treatment plan must include cessation of smoking (242). Chronic bronchitis is defined as the presence of productive cough on most days for at least 3 months per year and for at least 2 successive years (243). It is characterized by chronic airway inﬂammation and excessive mucus production. The histologic changes of emphysema include destruction of alveolar septa and distension of airspaces distal to terminal alveoli. The destruction of alveoli results in air trapping, loss of pulmonary elastic recoil, collapse of the airways in expiration, increased work of breathing, and significant ventilation-perfusion mismatching (243). The impaired ability to cough effectively and clear secretions predisposes patients with COPD to atelectasis and pneumonia in the postoperative period.
Patients with COPD and a history of heavy smoking account for most postoperative pulmonary complications in gynecologic surgical patients. The severity of COPD can be determined preoperatively via a thorough history and physical examination. According to recommendations regarding the use of preoperative pulmonary function tests by the American College of Physicians, these should be reserved for individuals in whom COPD is suspected, but unconfirmed (237,241). Typically, patients with COPD demonstrate impaired expiratory air ﬂow, manifested by diminished FEV1, forced vital capacity (FVC).
Data suggest that arterial blood gas measurements may show varying degrees of hypoxemia and hypercapnia: routine use of preoperative arterial blood gas measurement does not stratify patients into a higher risk subset for postoperative complications (236).
The preoperative preparation of the patient at risk for postoperative pulmonary complications should include cessation of smoking for as long as possible preoperatively; whereas 2 to 3 days of smoking abstinence are sufficient for carboxyhemoglobin levels to return to normal. One to 2 weeks of cessation decreases sputum volume. Two months of smoking abstinence is required to significantly lower the risk of postoperative pulmonary complications (236). Longer periods of abstinence can be counseled in patients undergoing elective surgery.
In patients with severe COPD, maximum improvement in airﬂow limitation can be achieved with a therapeutic trial of high-dose oral corticosteroids followed by a 2-week trial of high-dose inhaled steroid (beclomethasone 1.5 mg per day or the equivalent) in addition to inhaled bronchodilator therapy. Ideally, oral and inhaled steroid therapy should be initiated 1 to 2 weeks preoperatively. Inhaled steroids, in particular, address the inﬂammatory component of COPD. Oral steroid therapy initiated preoperatively should be maintained throughout the perioperative period and then tapered postoperatively. Beta-adrenergic agonist therapy can be initiated at least 72 hours preoperatively and is beneficial in patients who demonstrate either clinical or spirometric improvement on bronchodilators.
Patients with COPD and an active bacterial infection suggested by purulent sputum should undergo a full course of antibiotic therapy before surgery. The antibiotic used should cover the most likely etiologic organisms, Streptococcus pneumoniae and Haemophilus inﬂuenzae. In any patient with acute upper respiratory infection, surgery should be delayed if possible. The use of antibiotics to sterilize the sputum in the absence of evidence of an acute infection should be avoided because this practice may lead to bacterial resistance.