Why antihistamine drugs like suprastin do not block the stimulatory effect of histamine on these stomach cells

Rita schmidt, 74 years of age, is a female patient who was admitted to the surgical unit after undergoing removal of a section of the colon for colorectal cancer. the patient does not have a colostomy. the patient has several small abdominal incisions and a clear dressing over each site. the incisions are well approximated and the staples are dry and intact. there is a jackson-pratt drain intact with minimal serous sanguineous drainage present. the patient has a salem sump tube connected to low continuous wall suction that is draining a small amount of brown liquid. the patient has no bowel sounds. the foley catheter has a small amount of dark amber-colored urine without sediments. the patient has sequential compression device (scd) in place. the nurse performs an assessment and that the patient's breath sounds are decreased bilaterally in the bases and the patient has inspiratory crackles. the patient's cardiac assessment is within normal limits. the patient is receiving o2 at 2 l per nasal hg; heart rate 110 bpm; respiratory rate 16 breaths/min; and the patient is afebrile. the patient is confused as to place and time. cannula with a pulse oximetry reading of 95%. the vital signs include: blood pressure, 100/50 mm. a. explain the assessment parameters used to provide clues to detect postoperative problems early and the interventions needed. b. what gerontological postoperative considerations should the nurse make?