Immunology simplified

An understanding of the inflammatory and immune response is necessary to recognize conditions that alter these responses. Because normal inflammatory and immune responses are necessary for postoperative healing, the nurse needs to recognize patients at high risk for complications in the postoperative period. The first line of defense, comprised of anatomical barriers such as the skin and mucous membranes, is easily disrupted by instrumentation such as the surgeon's scalpel or any insertion of a tube, such as a central line. This provides easy access to multitudes of pathogens in the surgical patient. The second line of defense, the nonspecific inflammatory response, assists in the elimination of pathogens and the repair of damaged tissues. The cells crucial to the nonspecific inflammatory response may be impaired by drugs such as prednisone or by certain disease states, such as diabetes. The third line of defense, the specific immune response, uses the lymphocytes as effector cells. Patients with impaired immune systems, such as cancer patients, human immunodeficiency virus-positive patients, and severely malnourished patients, are at high risk for problems with postoperative healing because of their impaired immune status. High levels of anxiety and stress can also impair the ability to fight pathogens and to repair damaged tissues. Adequate preoperative teaching programs are beneficial in reducing the stress response and therefore are important in promoting the healing process.