The most common pulmonary disorder
Prevalence increases with age
Strongly associated with smoking
Male predominance
Many are asymptomatic but show expiratory airflow obstruction upon PFTs
Chronic Bronchitis or emphysema, many have features of both
Hypersecretion and inflammation
Productive cough most days for 2 years
Triggers: smoking, air pollutants, occupational dust exposure, recurrent pulmonary infections
Secretions and edema lead to obstruction
RV is increased in obstructive disease, intrapulmonary shunting (no perfusion), and hypoxemia common
Chronic hypoxemia leads to erythrocytosis (an increased circulating red blood cell mass resulting from a compensatory effort to meet reduced oxygen content), pulmonary hypertension, and eventually right ventricular failure (pumping against high resistance - cor pulmonale)
Pts develop CO2 retention, the ventilatory drive becomes less sensitive to arterial CO2 and may be depressed by O2 administration
Destruction of lung parenchyma
Reduced elastic recoil
Nearly always related to cigarette smoking
Early age: related to alpha1-antitrypsin deficiency (usually blocks elastase, so it doesn't break down lung elastic tissues) - if smoker then develops emphysema at an early age
Residual volume (RV), FRC, TLC, RV/TLC increased
Increased dead space
PaO2 and CO2 tension are usually normal
Purse lips to delay the closure of smaller airways
Assess respiratory status - dyspnea, sputum, wheezing
Pulmonary function test
Pre-operative goal:
Discuss possible post-op ventilation with the surgeon and patient
Optimal: stopped smoking 6-8 weeks before surgery, but 24 hrs can help improve oxygen carrying capacity
Bronchodilator treatment (beta-2 agonist)
Consider digitalis treatment if pt has cor pulmonale with right ventricular failure
Regional: risk of high with decreased pulmonary function
Respiratory depression with anesthetics
Small TV, slow rates to avoid air trapping
Check ABG for accurate assessments
Risk of pneumothorax, especially with positive pressure ventilation