Injury, Int. J. Care Injured (2006) 37S, S3–S9 www.elsevier.com/locate/injury Surgical stress response Peter V. Giannoudis a, *, Haralambos Dinopoulos a , Byron Chalidis a , George M. Hall b a Academic Department of Trauma & Orthopaedic Surgery, School of Medicine, University of Leeds, LGI University Hospital, Leeds, UK b Department of Anaesthesia & Intensive Care Medicine, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK KEYWORDS Trauma; Surgical stress; Inflammatory response; Cytokines Summary Recent advances in molecular medicine have allowed the characteri- zation and quantification of inflammatory cascades following surgery and trauma. Activation of immune cells is followed by the release of various cytokines as well as by migration of leukocytes into inflamed tissues. Various methods have been developed in order to modulate the immune–inflammatory system and at the same time to prevent overreaction and unexpected complications. In this context, the magnitude of surgical stress exerted on the patient is of paramount importance. Several factors, either controllable or not, are known to contribute to the development and amplification of the ‘surgical stress response’. Therefore, they should be taken into consideration by both surgical practitioners and other medical specialties involved in the management of the traumatised patient. © 2006 Elsevier Ltd. All rights reserved. Introduction During the past century many improvements have been made in disciplines of medicine such as pre- hospital care, anaesthetics, diagnostics, intensive care medicine, genetics, molecular medicine and biology. The physiologic response to injury has been described as consisting of 3 phases: (a) hypodynamic ebb phase (shock), where the human body attempts to limit the blood loss and to maintain perfusion to the vital organs; (b) hyperdynamic flow phase, characterised by increased blood flow which aims to remove waste products and to allow nutrients to reach the site of injury for repair and (c) recuperation * Corresponding author. Professor Peter V. Giannoudis. Academic Department of Trauma & Orthopaedics, LGI University Hospital, Clarendon Wing, Great George St, Leeds, LS1 3EX, UK. Tel: +44 113 3922611; fax: +44 113 3923290. E-mail: pgiannoudi@aol.com (P.V. Giannoudis). phase, which lasts for months and attempts to return the human body to its pre-injury level 1 . However, as knowledge has continuously accumulated, especially during the last 20 years, it has become clear that the physiologic response to injury is not as simplistic as initially described and represents a rather complex physiological phenomenon. Even today it is not completely understood. The reaction of the human body to various nox- ious stimuli is termed as ‘stress response’ 2,3 . Any factor that exerts an action on the human tissues can influence the fine balance of homeostasis. Trauma, diseases, co-morbidities and medication can potentially trigger the state of physiological ‘stress’. In particular, surgical procedures lead to a variety of profound physiological alterations characterised by changes in haemodynamics, endocrine and immune functions 4,5 . Under normal 0020-1383/$ – see front matter © 2006 Elsevier Ltd. All rights reserved.