Notes on Practice: An Interesting Side Effect of Home Oxygen Therapy
The concept of oxygen as a therapeutic agent was initially proposed by Alvin Barach in the 1920s.1 Well-conducted clinical trials have clearly demonstrated major therapeutic benefit for patients with chronic obstructive pulmonary disease.2,3 Currently, long-term oxygen therapy is recommended for patients with hypoxemia, defined as a PaO2 of less than or equal to 55 mm Hg or an oxygen saturation of <88%. Patients with a PaO2 of 56 to 59 mm Hg or an oxygen saturation of 89% with either cor pulmonale or polycythemia also should receive continuous oxygen therapy.4 This is a report of an unusual complication of home-oxygen therapy.
Sixty-nine year old Mr. C was seen in clinic for follow-up after a recent hospitalization for pneumonia. He has a history of chronic obstructive pulmonary disease (COPD) and has required home oxygen for the last 6 years. His stage T3N0M0 non-small cell lung cancer was diagnosed 6 years ago and treated with radiotherapy. Comorbidities include diabetes mellitus, atrial fibrillation, and long-standing chronic paranoid schizophrenia. His last pulmonary function test done 1 year before his pneumonia revealed an FEV1 of 1.05 L (30% predicted), FVC of 2.15 L (51% predicted), and FEV1/FVC of 49%. A room air arterial blood gas measurement at that time revealed a pH of 7.35, with pCO2 of 65 mm Hg and pO2 of 55 mm Hg. His medications included warfarin, lovastatin, digoxin, glyburide, long-acting diltiazem, tamsulosin, and ipratropium bromide metered dose inhaler.
On physical examination, it was noted that his oxygen tubing had eroded part of his right ear; the scapha had become detached from the head (Figures 1 and 2). He had no spontaneous complaints pertaining to his ear. There was no evidence of infection (no redness, warmth, or drainage), erosion, or ulceration. If the detachment were surgically repaired and appropriate measures subsequently instituted (use of helmet or foam padding), recurrence could be avoided. He was offered surgical repair, but he declined.
Treatment and Prognosis
His family recently devised a "helmet" for him that reduces the pressure applied to his ear by fastening a large safety pin to each sides of his cap several inches above the ear and passing the tubing through the opening in the safety pin.
Oxygen therapy has been shown beneficial in improving pulmonary hemodynamics, exercise capacity, the work of breathing, neuropsychological performance, and mortality in patients with chronic obstructive pulmonary disease.4 Complications of home oxygen therapy include nasal congestion, skin rash, irritation of the nasal mucosa, epistaxis, and fire hazard from the oxygen, as well as social and psychological problems resulting from the perceived stigma of wearing oxygen.5 Mr. C developed erosion of the ear where the scapha became detached from the head. This rare complication can be prevented with the early use of foam padding to relieve some of the pressure.
1. Barach AL. The therapeutic use of oxygen. JAMA. 1922;79 693-698.
2. Nocturnal Oxygen Therapy Trial Group. Continuous and nocturnal oxygen therapy in hypoxemic chronic obstructive lung disease: a clinical trial. Ann Intern Med. 1980;93:391-398.
3. Report of the Medical Research Council Working Party. Long-term domiciliary oxygen therapy in chronic cor pulmonale complicating chronic bronchitis and emphysema. Lancet. 1981;1 681-685.
4. Tarpy SP, Celli BR. Long-term oxygen therapy. New Engl J Med. 1995;333:710-714.
5. Benditt JO. Adverse effects of low-flow oxygen therapy. Respiratory Care. 2000;45(1):54-61.