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<b>Anaesthetic Management of Abdominal Aortic Surgery<br> Hossam El-Ashmawi</b><br> Abdominal aortic aneurysm (AAA) is defined as a focal dilation of the abdominal aorta leading to a diameter at least 50% larger than normal, or a diameter greater than 3 cm in an average person. The prevalence of AAAs is estimated to be 2–5% in patients over 65 years. Established risk factors for development of AAAs include age, male gender, history of smoking, and a first-degree relative with AAA. In the United States, approximately 30,000 patients die from ruptured AAAs each year, and this number might be higher worldwide. The most important risk factor for rupture is aneurysm diameter. Patients with aneurysm diameters 3.6 cm have a 10–20% chance of rupture per year, with an associated mortality of around 85%. This lecture will review the anaesthetic challenges and considerations during open surgical reconstruction of the abdominal aorta with special reference to abdominal aortic aneurysms. Open surgical reconstruction of the abdominal aorta is a complex and challenging procedure. Although endovascular aortic repair is becoming more common, open repair remains the gold standard. Successful anaesthetic management of open abdominal aortic surgery requires a clear understanding of the pathophysiology of aortic diseases as well as the proposed surgical techniques. Because these patients usually have significant co-morbidities, a thorough preoperative examination and evaluation is mandatory for successful perioperative management. Intraoperative challenges include rapid fluid shifts, haemorrhage, hypothermia, clamping and unclamping of the aorta, as well as organ protection during ischaemia. Several anaesthetic techniques have been successfully used for open aortic reconstruction including general anaesthesia, regional anaesthesia, or a combined technique. The aim is to provide stable haemodynamics and maintain vital organ perfusion and function. Patients with poor left ventricular function might not tolerate inhalation anaesthetic agents and will benefit from an opioid-based technique. On the contrary, potent inhalation anaesthetics could be desirable to control haemodynamics in patient with good LV function. Most patients are admitted to the intensive care unit postoperatively. The duration and intensity of postoperative care are dependent on the preoperative condition, intraoperative physiologic derangements e.g. long durations of aortic cross-clamping, large volumes of IV blood or fluid transfusion, and hypothermia, as well as the development of postoperative complications such as cardiac complications, chest infection, renal dysfunction, ileus, and sepsis. Analgesia should be adequately provided either by regional techniques or systemic drugs to alleviate pain, facilitate extubation, enhance recovery and ambulation, and minimize complications. In conclusion, anaesthetic management of patients undergoing surgical treatment of AAA requires a continuum of care from preoperative assessment, through intraoperative anaesthesia and postoperative critical care to achieve a successful outcome for the patient.<br> Further Reading: 1. Norris E. Anesthesia for Vascular Surgery. In: Miller R (ed). Miller’s Anesthesia. Elsevier, Saunders; Philadelphia, 2015; 2106 - 57. 2. Gelzinis T and Subramaniam K. Anesthesia for Open Abdominal Aortic Aneurysm Repair. In: Subramaniam K, Park K, Subramaniam B (eds). Anesthesia and Perioperative Care for Aortic Surgery. Springer; New York, 2011; 301 - 27.