Preoperative assessment for cardiac surgery

Cardiac surgery carries a relatively high morbidity and mortality compared with most other surgical procedures. This is not only due to the nature of the surgery itself, but also to the presence of cardio-respiratory and other co-morbidities. Preoperative history taking and examination should focus on the assessment of the severity of ischaemic heart disease and cardiac failure, as well as identifying the presence and severity of co-morbidities such as diabetes mellitus, hypertension and smoking-related diseases. Risk stratification, using one of several well-established scoring systems, can help estimate a patient's prognosis. As well as routine serological tests, a number of specialized investigations are commonly performed as part of a preoperative work-up. These include evaluation of anatomical anomalies (CT, MRI or echocardiography), myocardial perfusion defects (using radionuclide scanning techniques), and assessment of functional reserve with cardiopulmonary exercise testing. An understanding of these investigations and their results will aid the anaesthetist in planning a perioperative strategy. In this review, we discuss the salient points of preoperative assessment of the cardiac surgical patient, including the use of scoring systems for evaluation of symptom severity and risk stratification. Specialised investigations are also discussed. In addition, we briefly outline the principles of the preoperative discussion with the patient, including consent for invasive procedures and premedication.