A 67-year-old woman with moderate chronic obstructive pulmonary disease comes to the physician to discuss plans for upcoming air travel from Boston to California. She leads a sedentary lifestyle and has mild occasional cough but no significant dyspnea with household activities. One year ago, she was hospitalized with exacerbation of chronic obstructive pulmonary disease and was treated with noninvasive ventilation, corticosteroids, and antibiotics. The patient's other medical problems include coronary artery disease with stent placement 2 years ago. Her left ventricular ejection fraction is normal. Current medications include tiotropium, salmeterol, albuterol as needed, aspirin, clopidogrel, atorvastatin, metoprolol, and losartan.
Her blood pressure is 122/70 mm Hg, pulse is 75/min, and respirations are 16/min. Pulse oximetry is 96% on room air at rest. Pulmonary examination shows minimal bilateral end-expiratory wheezes. Cardiac examination is within normal limits. There is no peripheral edema. Forced expiratory volume in 1 second on spirometry 6 months ago was 55% of predicted.
Which of the following is the best next step in management of this patient?

Question

A 67-year-old woman with moderate chronic obstructive pulmonary disease comes to the physician to discuss plans for upcoming air travel from Boston to California.  She leads a sedentary lifestyle and has mild occasional cough but no significant dyspnea with household activities.  One year ago, she was hospitalized with exacerbation of chronic obstructive pulmonary disease and was treated with noninvasive ventilation, corticosteroids, and antibiotics.  The patient's other medical problems include coronary artery disease with stent placement 2 years ago.  Her left ventricular ejection fraction is normal.  Current medications include tiotropium, salmeterol, albuterol as needed, aspirin, clopidogrel, atorvastatin, metoprolol, and losartan.
Her blood pressure is 122/70 mm Hg, pulse is 75/min, and respirations are 16/min.  Pulse oximetry is 96% on room air at rest.  Pulmonary examination shows minimal bilateral end-expiratory wheezes.  Cardiac examination is within normal limits.  There is no peripheral edema.  Forced expiratory volume in 1 second on spirometry 6 months ago was 55% of predicted.
Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec193a_98e1_91ff_853d_051805d0d215_MD0002_00 Decreased partial pressure of oxygen in pressurized cabins during airplane flights may increase the risk of hypoxemia in patients with pulmonary disease. Cabin altitudes are pressurized to 8000 feet, at which the fraction of inspired oxygen falls to 0.15 versus the normal 0.21 at sea level. This correlates to a drop in oxygen saturation to 89%-94% in healthy passengers. Most healthy individuals can compensate for this small degree of hypoxia. However, patients with severe unstable obstructive lung disease may not be able to compensate and can develop symptoms (eg, lightheadedness, chest pain, tingling in the extremities, palpitations, increased dyspnea). 11ec193a_98e1_9200_853d_e799615bfbfc_MD0002_00 Forced expiratory volume in 1 second (FEV₁) and pulse oximetry (SpO₂) can help assess clinical severity of lung disease. Patients with SpO₂ >95% are generally not at risk for in-flight hypoxemia and do not require further testing. Those with SpO₂ of 92%-95% are also not at risk unless they have other factors (eg, previous dyspnea during air travel, inability to walk 50 m without respiratory distress, FEV₁ <50%, or moderate to severe pulmonary hypertension). These patients require further testing and may need oxygen supplementation prior to air travel. Supplemental oxygen (2 L/min) is recommended during flights for patients with resting SpO₂ <92%. If the patient is already on home oxygen, an increase of 1-2 L/min from baseline is recommended. This patient has stable chronic obstructive pulmonary disease with SpO₂ >95% at rest and requires no supplemental oxygen or further testing prior to air travel (Choices A, D, and E). (Choice B) A hypoxia altitude simulation test is used to predict in-flight hypoxemia when results of pulse oximetry are inconclusive. The test involves having the patient breathe in a mixture of nitrogen and oxygen at 15% (normal room air is 21%) for 20 minutes. In-flight supplemental oxygen is usually required if SpO₂levels are <85% (PaO₂ <50 mm Hg) at any point during the test. Educational objective: Patients with stable chronic obstructive pulmonary disease and pulse oximetry >95% on room air can travel by air without the need for additional testing or in-flight oxygen supplementation. Further testing is required for patients with pulse oximetry (SpO₂) of 92%-95% and risk factors (eg, forced expiratory volume in 1 second <50%, moderate to severe pulmonary hypertension). The preferred method is hypoxia altitude simulation test. Supplemental oxygen is recommended during flights for patients with resting SpO₂ <92%. __________ References: Flying with respiratory disease. (http://www.ncbi.nlm.nih.gov/pubmed/20395674) Air travel and chronic obstructive pulmonary disease: a new algorithm for pre-flight evaluation. (http://www.ncbi.nlm.nih.gov/pubmed/22767877)

A 67-Year-Old Woman with Moderate Chronic Obstructive Pulmonary Disease Comes