Coronary artery stents and non-cardiac surgery.

The utility of interventional cardiology has developed significantly over the last two decades with the introduction of coronary angioplasty and stenting, with the associated antiplatelet medications. Acute coronary stent occlusion carries a high morbidity and mortality, and the adoption of therapeutic strategies for prophylaxis against stent thrombosis has major implications for surgeons and anaesthetists involved in the management of these patients in the perioperative period. Currently, there is limited published information to guide the clinician in the optimal care of patients who have had coronary stents inserted when they present for non-cardiac surgery. This review examines the available literature on the perioperative management of these patients. A number of key issues are identified: the role of surgery vs percutaneous coronary intervention for coronary revascularization in the preoperative period; the different types of coronary stents currently available; the emerging issues related to drug-eluting stents; the pathophysiology of coronary stent occlusion; and the recommended antiplatelet regimes that the patient with a coronary stent will be receiving. The role of preoperative platelet function testing is also discussed, and the various available tests are listed. Appropriate management by all the clinicians involved with patients with coronary stents undergoing a variety of non-cardiac surgical procedures is essential to avoid a high incidence of postoperative cardiac mortality and morbidity. The review examines the evidence available for the perioperative strategies aimed at reducing adverse outcomes in a number of different clinical scenarios.

Methods of detecting atherosclerosis in non-cardiac surgical patients; the role of biochemical markers.

Atherosclerosis is a common condition in both the developed and developing world and is now recognised to be an inflammatory condition leading to the development of ischaemic heart disease, cerebrovascular disease and peripheral vascular disease. Ischaemic heart disease is a major risk factor in the pathogenesis of perioperative adverse cardiovascular events which lead to significant morbidity and mortality within the high risk surgical patient population. Current methods of evaluating the likelihood of postoperative cardiovascular complications depend largely on risk scoring systems, and the preoperative assessment of the functional status of the cardiovascular system. However, the possible role of inflammation in the generation of atherosclerosis has led to the identification of several biochemical markers such as acute phase proteins, cellular adhesion molecules and cytokines. An alternative approach therefore is the measurement of preoperative levels of these biomarkers with the aim of assessing pre-existing disease activity. This review summarises the pathophysiology of atherosclerosis and perioperative myocardial infarction, and discusses the possible future role of biomarkers in the risk stratification of patients undergoing non-cardiac surgery.

Sentinel node localization and biopsy in breast cancer.

Currently, it is routine practice to carry out axillary lymph node dissection at the time of surgical removal of a malignant primary breast tumour. As breast cancer is being diagnosed at an earlier stage in a growing percentage of cases, this procedure is proving unnecessary in a proportion of patients. Axillary lymph node dissection carries a risk of side effects and ideally we should identify the patients who actually require the procedure. The concept of the sentinel node is not new and was developed over twenty years ago. The technique of lymphoscintography was initially used to identify the sentinel node/s in patients with malignant melanoma. A proposed alternative management strategy to routine axillary lymph node dissection in patients with breast cancer is sentinel lymph node localization using lymphoscintography and biopsy of the identified sentinel node. The aim being to accurately predict the disease status of the axilla and consequently determine whether axillary lymph node dissection is indicated. The technique is currently undergoing a multi-centre trial in the UK. During my elective at St Luke's Cancer Centre, Royal Surrey County Hospital, Guildford I was fortunate to observe this procedure being tested, with patients undergoing both lymphoscintography and sentinel node biopsy as well as axillary lymph node dissection. The results seen during my stay were extremely encouraging.