Surgical stress: the role of pain and analgesia.

The endocrine, metabolic and inflammatory responses to injury and infection are composed of a variety of physiological changes often grouped together and called the surgical stress response. Over the past few decades, detailed knowledge has accumulated on this response and has allowed consideration and development of therapeutic manoeuvres designed to assist or manipulate the patient's response to a surgical operation in order to improve postoperative morbidity. Since relief of postoperative pain is supposed to be a prerequisite for improved postoperative outcome, this paper summarizes the effects on the surgical stress response of the available techniques. A short review of the clinical implications of postoperative pain relief will also be given. It is not intended to give a complete bibliography of this vast topic, but primarily to bring recent findings into balance with previous data. The reader is therefore referred to recent reviews of the surgical stress response, including release mechanisms and modifying factors [7,13, 14,16,17,25].