Which of the following is the most appropriate step to take next for this patient after he is admitted to the hospital? A 64-year-old man with moderate chronic obstructive pulmonary disease presents to your office complaining that for the past 5 days, he has been experiencing worsening shortness of breath. He denies having fevers or chills, but he does report increasing purulent sputum production. He visited his 6-year-old grandson this past weekend, and the child had symptoms of an upper respiratory infection. The patient's vital signs are normal except that oxygen saturation on room air is 88%. Examination reveals bilateral expiratory wheezing. A chest radiograph is normal. Results of laboratory testing are as follows: white blood cell count, 12,500/mm3; arterial blood gas pH, 7.35; arterial oxygen tension (PaO2), 65 mm Hg; and carbon dioxide tension (PCO2), 60 mm Hg. You arrange for hospital admission.
A. Mechanical ventilation B. Noninvasive positive-pressure ventilation C. Supplemental oxygenation via nasal cannula D. Continuous oxygen saturation monitoring
Supplemental oxygenation via nasal cannula-acute hypercapnic respiratory failure is defined as an arterial carbon dioxide tension (paco2) greater than 45 to 50 mm hg, in association with respiratory acidosis. chronic failure is also marked by an elevation in arterial carbon dioxide tension (paco2), but in patients with chronic respiratory failure, renal compensation tends to normalize the ph. the distinction between acute and chronic hypercapnic respiratory failure is important, because the two have different prognoses and therapeutic implications. signs and symptoms of hypercapnia depend not only on the absolute level of paco2 but also on the rate at which the level increases. a paco2 higher than 100 mm hg may be well tolerated if the hypercapnia develops slowly and acidemia is minimized by renal compensatory changes. however, acute increases in paco2 levels may produce many neurologic symptoms and signs, including confusion, headaches, seizures, and coma. nasal cannulas allow patients to eat, drink, and speak during oxygen administration. the disadvantage is that the exact fraction of inspired oxygen (fio2) that is delivered is not known, because fio2 is influenced by peak inspiratory flow demand. noninvasive positive pressure ventilation is not indicated for patients with cardiac or respiratory arrest; nonrespiratory organ failure; impaired consciousness; unstable cardiac rhythms; hemodynamic instability; severe upper gastrointestinal bleeding; inability to protect the upper airway or clear secretions; or facial surgery, trauma or deformity. when adequate oxygenation cannot be obtained by noninvasive means or if progressive hypoventilation and hypercapnia with respiratory acidosis occurs, endotracheal intubation and mechanical ventilatory support should be initiated.