It is often said that the anesthesiologist is the internist of the operating room (OR). By extension, the cardiac anesthesiologist becomes the cardiologist of the OR. Even though it is certainly true that anesthesiologists have knowledge of medicine in general and cardiology in particular, the practice of cardiac anesthesia is a unique discipline unto itself. Although cardiac anesthesiologists must understand why someone is being taken to cardiac surgery, they will not be the ones to decide if surgery is or is not indicated. Rather, cardiac anesthesiologists must review the totality of the patient’s cardiac and medical history to determine the best approaches to manage these often very sick patients throughout the perioperative period.
This chapter will briefly examine how someone is referred for cardiac surgery and the essential elements of preoperative evaluation necessary for patient management. Frequent visitation to the American Heart Association website (www.my.americanheart.org) is suggested as a starting place to find the latest guidelines on the medical management of cardiovascular disease. Although these statements are generally directed to patient care outside of the cardiothoracic operating room, cardiac anesthesiologists should review the current guidelines for cardiovascular disease management.
CONSENT FOR CARDIAC ANESTHESIA
From the smallest hypoxemic infant with congenital heart disease to the 90-year-old patient with aortic stenosis, the cardiac anesthesiologist is called upon to care for a wide range of patients. Patients undergoing the same type of surgery can vary greatly depending upon their preoperative comorbidities and the impact their disease has had upon their cardiac function. A patient with well-preserved ventricular function presents far different challenges than an individual with reduced ejection fraction and heart failure. Likewise, the patient who has intact kidney function and is free of diabetes and lung disease is potentially less problematic than the person afflicted with these comorbidities. In this regard the conduct of cardiac anesthesia parallels that of any anesthetic. A patient’s comorbidities are considered as the anesthetist determines the appropriate anesthetic technique, monitoring, and plan for postoperative management. What is perhaps unique about cardiac anesthesia is that so many of these comorbidities are regularly present; the “routine” cardiac surgery patient is incredibly sick both as a consequence of having primary heart disease as well as the associated illnesses that occur frequently in this patient population.
Generally, the “routine” cardiac surgery patient is designated as an American Society of Anesthesiologists (ASA) class 3 or 4. All patients are informed of the inherent risk of death, stroke, neurological dysfunction, and/or kidney injury. The risks and benefits of transesophageal echocardiography (TEE) should likewise be discussed with the patient preoperatively. Although the risk of stroke following bypass surgery is low (3%)1 and that of death even lower, cardiac surgery is associated with multiple postoperative morbidities including cognitive dysfunction, kidney injury, gut ischemia, blood product transfusion, and potentially prolonged treatment in the intensive care unit (ICU). Because both the surgeon and the anesthesia ...