Dr TANG Kam Shing
Abstract
Care of patients in the immediate post-operative phase of major surgery is one of the major functions of intensive care units. As the general population is getting older, an increasing proportion of these post-operative patients would be suffering from multiple medical co-morbidities. Common medical co-morbidities like hypertension, diabetes mellitus and hyperlipidemia predispose one to develop ischemic heart disease, which can easily manifest during stressful situations such as post-operative state. As a result, intensive care physicians are likely to see increasing numbers of myocardial ischemia or even infarction in the immediate post-operative period. Vigilance in identification of patients most at risk of this dreadful complication is therefore much needed.
This paper will be divided into 2 parts. The first part is a literature review looking into several important aspects of post-operative myocardial ischemia. This part will cover the prevalence of peri-operative myocardial ischemia and the usefulness of various diagnostic tools, namely ECG, cardiac enzymes and troponins. The prognostic significance of post-operative myocardial ischemia or infarction will also be a focus of review.
The second part of this paper will be a retrospective cohort study on post-operative patients admitted to the intensive care unit of Queen Elizabeth Hospital. The primary aim of this study is to estimate the prevalence of post-operative troponin T leak in patients admitted into a general adult intensive care unit after major non-cardiac surgery. The secondary aim is to explore if there are any significant pre-operative and intra-operative risk factors for post-operative troponin T leak in this specific population. Pre-operative risk factors are relatively well studied in the literature. However, potential intra-operative risk factors such as hypotension, hypothermia, blood loss, electrolyte disturbances and acid-base disturbance have never been specifically investigated. This study will try to shed some light on this particular aspect of post-operative myocardial ischemia.
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