Pre-Operative Assessment * Full blood count. A full blood count (FBC) is needed for major operations, in the elderly and in those with anaemia or pathology with ongoing blood loss and chronic disease. In case of suspicion or history of sickle crisis, a sickle cell Test is needed in patients of Afro-Caribbean and Indian subcontinent origin. * Urea and electrolytes. Urea and electrolytes (U&Es) are needed before all major operations, in most patients over 65 years of age especially with cardiovascular, renal and endocrine disease, or if significant blood loss is anticipated. It is also needed in those on medications that affect electrolyte levels, e.g. steroids, diuretics, digoxin, non-steroidal anti-inflammatory drugs, intravenous fluid or nutrition therapy and endocrine problems. * Electrocardiography. Electrocardiography (ECG) is required for those patients over 65 years of age and symptomatic patients with a history of rheumatic fever, diabetes, cardiovascular, renal and cerebrovascular disease, with and without severe respiratory problems. It will also depend on if the surgery is minor/intermediate or major. * Chest radiograph. Cost-effectiveness and risks of radiationexposure mean that chest radiographs should be restricted to specific patients, such as those with cardiac failure, severe chronic obstructive pulmonary disease (COPD), acute respiratory symptoms, pulmonary cancer, metastasis or effusions or those who are deemed to be at risk of active pulmonary tuberculosis. * Clotting screen. If a patient has a history suggestive of a bleeding diathesis, liver disease, eclampsia, cholestasis or has a family history of bleeding disorder, or is on antithrombotic or anticoagulant agents then coagulation screening will be needed. However, the effects of anti- platelet agents, low molecular weight heparins and newer agents affecting factor Xa cannot be measured by routine Laboratory tests. * Urinalysis. Dipstick testing of urine should be performed on all patients to detect urinary infection, biliuria, glycos- uria and inappropriate osmolality. * b-Human chorionic gonadotrophin. Women of child-bearing age should be asked sensitively about their pregnancy status. If in doubt a laboratory test or a reliable pregnancy kit (low cost) can be used, after obtaining consent from the patient, to avoid danger of exposure to surgery and anaesthesia on the foetus. * Blood glucose and HbA1c. Poor control of diabetes can lead to perioperative infection and slow recovery in patients with diabetes mellitus and endocrine problems. HbA1C indicates how well diabetes has been controlled over a longer duration. Early mobilisation, oral intake and return to routine medication should be the goals in management of diabetes. * Aerial blood gases. A low-cost tool that can give quick and vital information in acute or chronic severe respiratory conditions, acid-base disturbances and conditions where there is changing milieu, e.g. immediately before kidney transplant. * Liver function tests. These are indicated in patients with jaundice, known or suspected hepatitis, cirrhosis, malignancy or in patients with poor nutritional status. * Other investigations. Specialist radiological views and recent imaging are sometimes required. If imaging is going to be needed during surgery, then this needs to be planned in advance. Ref: Bailey and love 27th edition Pgno : 256