Which anesthetic techniques are appropriate for AAA surgery?

Which anesthetic techniques are appropriate for AAA surgery?

All antihypertensive and anti-anginal medications should be continued until the time of surgery. Preoperative sedation should be based on the patient’s clinical condition and concurrent medical diseases. Some form of anxiolysis should be administered, as hypertension and tachycardia may increase the risk of aneurysm leakage or rupture, or induce myocardial ischemia in patients with concurrent coronary artery disease. Patients presenting for aortic surgery may be very unstable hemodynamically due to ongoing hemorrhage, myocardial ischemia, and/or conges-tive heart failure. Organ malperfusion is also a major problem. It is, therefore, recommended that patients who present for emergency aortic surgery are intensely moni-tored in order to control blood pressure and resuscitate appropriately.

In patients with aortic disease, the paramount goal is the maintenance of hemodynamic stability, while provid-ing amnesia, analgesia, and immobility. As the aorta remains at risk of rupture or extension of the dissection, blood pressure must be strictly controlled. β-Adrenergic blockade and vasodilators are the mainstays for minimiz-ing the driving force and the ejection velocity of blood, while maintaining adequate perfusion pressure. At the other end of the spectrum are patients who present in hypovolemic shock due to leaking or rupture of the aorta. In this situation, maintaining volume status, securing the airway, and immediate surgical control are the main goals.

All patients presenting for emergency aortic surgery are considered to have a full stomach, while elective cases must be considered individually. Avoidance of hemodynamic aberrations during induction and tracheal intubation is desirable. Any number of anesthetic agents can accomplish these goals and the choice is a personal decision that is dependent on the clinical situation. High-dose opioid tech-niques are still commonly employed for those patients in whom postoperative ventilatory support is anticipated; however, normothermic, hemodynamically stable patients may be considered for early extubation. Vasoactive medica-tions, such as nitroprusside, nitroglycerin, and esmolol should be prepared preoperatively, including diluted amounts for bolus administration (Table 36.1).