Mr. Cohen, a 75-year-old male with COPD and emphysema, was admitted to the hospital for an exacerbation of his COPD. He requires oxygen and respiratory treatments. He complains of lower back pain from keeping his bed elevated and is prescribed Percocet. After receiving Percocet, his pain decreases but his oxygen levels drop when walking. Respiratory therapy is called to administer an albuterol treatment, after which his breathing improves. As his nurse, you must monitor his respiratory status, pain levels, and implement interventions to improve his breathing and mobility.