Yоu аre summоned tо evаluаte a 45-year old female, who is two days post abdominal surgery and is conscious, oriented and dyspneic. Her vital signs reveal a HR of 115 b/m, Respiratory rate of 30 bpm, and Temperature of 37 C. The patient has been performing flow-oriented incentive spirometry for the last two days at a frequency of TID and 10 sustained deep breaths each treatment. Auscultation of the patient's lungs reveal diminished breath sounds in both bases accompanied by a few late inspiratory crackles. Which of the following modifications to therapy would you recommend for this patient?