The major goals of anesthesia include analgesia (pain relief), amnesia (lack of recall), hemodynamic stability, and perhaps muscle relaxation (paralysis). Table 17.2 presents the variety of most common ways the anesthesiologist may safely attain these goals (methods of attaining hemodynamic stability will be addressed later). Most commonly, a combination of intravenous opioid (analgesia), intravenous benzodiazepine (amnesia), and inhalational anesthetic (analgesia and amnesia) is used for induction and maintenance of anesthesia. In the current era of “fast-tracking”, specific drugs and amounts are chosen for specific anesthetic goals in each individual patient in order to allow the patient to awaken from anesthesia in the immediate postoperative period. Thus, short-acting drugs (fentanyl, midazolam) and/or inhalational anesthetics are favored.

The term monitored anesthesia care (MAC) generally implies intravenous sedation without laryngeal intubation. Most commonly, a combination of intravenous opioid and benzodiazepine is administered to a spontaneously breathing patient and titrated to facilitate surgery while keeping the patient comfortable. Because amounts of opioid and benzodiazepine must be carefully kept to an appropriate minimum (both drug classes promote respiratory depression), only certain minimally invasive surgeries may be performed in patients with heart failure under monitored anesthesia care. Procedures that may be amenable to MAC include pacemaker insertion/replacement, transcatheter aortic valve implantation, transesophageal echocardiography, and cardioversion.

The term regional anesthesia generally implies the use of a wide variety of peripheral nerve blocks (parasternal block, intercostal nerve block, etc.), intrathecal techniques, and/or epidural techniques [1]. While general anesthesia may be supplemented with regional anesthetic techniques, the traditional use of the term regional anesthesia usually implies the use of regional anesthetic techniques and intravenous sedation in a spontaneously breathing patient. Thus, amounts of intravenous opioid and benzodiazepine must be carefully kept to an appropriate minimum, limiting the scope of surgeries that may be performed in patients with heart failure under regional anesthesia.

Use of regional anesthetic techniques in patients undergoing cardiac surgery, while seemingly increasing in popularity, remains extremely controversial, prompting numerous Editorials by recognized experts in the field of cardiac anesthesia. One of the main reasons such controversy exists (and likely will continue for some time) is that the numerous clinical investigations regarding this topic are suboptimally designed and utilize a wide array of disparate techniques preventing clinically useful conclusions all can agree on [2–5].

The term general anesthesia usually implies the use of moderate to large doses of intravenous agents and/or inhalational agents (with or without intravenous muscle relaxants) along with endotracheal intubation and mechanical ventilation. The vast majority of cardiac surgeries performed in patients (with or without heart failure) are performed under general endotracheal anesthesia. The total control over the respiratory system via mechanical ventilation allows the anesthesiologist to administer large amounts of intravenous anesthetics and/or inhalational anesthetics to the patient, permitting invasive cardiac surgery to occur. General anesthesia is sometimes supplemented with regional anesthetic techniques.

The goals of premedication include decreased patient anxiety, production of amnesia, and minimization of pain associated with vascular cannulation in the preanesthetic period without producing ventilation or cardiac depression. These goals are most commonly met by administering small and appropriate amounts of intravenous opioids for analgesia and intravenous benzodiapines for amnesia. Additionally, most anesthesiologists have patients take their routine cardiovascular medications (beta-adrenergic blockers, etc.) the morning of surgery (with small sips of water) in hopes of promoting perioperative hemodynamic stability.

Numerous physiologic parameters are monitored in patients undergoing cardiac surgery (Table 17.3). Arterial blood pressure may be monitored noninvasively or invasively. Cardiac rate and rhythm is assessed via electrocardiography. Cardiac function (preload, myocardial contractility, etc.) is most commonly monitored via the pulmonary artery catheter and/or transesophageal echocardiography, and will be discussed in greater detail later in this chapter. Pulmonary function is assessed in a wide variety of ways, including assessment of pulmonary compliance and interpretation of arterial blood gas tensions (oxygen, carbon dioxide). Urine output is closely monitored in all patients undergoing cardiac surgery, especially so in patients with preoperative renal dysfunction. Maintenance of normothermia in patients is extremely important (and sometimes difficult), especially in cardiac surgeries without assist of cardiopulmonary bypass. Numerous arterial blood samples are obtained perioperatively in order to monitor pulmonary function, a wide variety of serum electrolytes (potassium, magnesium, etc.), glucose levels, and hemoglobin levels. Frequent assessment of coagulation is important as well, because essentially all patients undergoing cardiac surgery will be subjected to at least some degree of anticoagulation (and possibly reversal of anticoagulation). Cerebral function monitoring is somewhat controversial. Neurologic insult (via microemboli and/or macroemboli) continues to haunt cardiac surgery. Although numerous investigators have valiantly tried, we are still without a monitor that reliably and effectively predicts intraoperative recall or the development of postoperative neurologic insult (stroke or diffuse neuropsychological dysfunction).

Intraoperative transesophageal echocardiography (TEE) was introduced in 1980s, and there has been significant development in training and technology since that time. The most common applications intraoperatively include assessment of left and right ventricular function, valvular anatomy and function, intracardiac air, clot, or masses, detection of pericardial fluid, and evaluation of the aortic root and ascending aorta. Minhaj et al. found that the routine use of TEE during cardiac surgery revealed new findings in 30 % of patients and of these 20 % had a change in surgical plan [6]. Many cardiothoracic anesthesiologists undergo extensive training and/or certification in perioperative TEE. Newer three dimensional technology is available that allows very accurate reconstruction of anatomy and assessment of function. It is particularly useful in mitral valve repair because of the ability to accurately identify the lesion (P2, ruptured cordae, etc.) and target the surgical approach.

Prior to induction of general anesthesia in patients scheduled for cardiac surgery, a wide variety of items need to be prepared and checked out. The anesthesia machine needs to be checked out and airway materials (laryngoscope) prepared. Appropriate medications (anesthetic drugs, potent cardiovascular drugs) need to be prepared as well. Preoperatively, peripheral venous access is obtained and intravenous premedication administered. Most anesthesiologists insert invasive arterial catheters (usually radial artery) prior to induction of general anesthesia. Induction of anesthesia (depending on the choice and dose of drugs and the patients’ cardiac reserve) can result in significant hemodynamic changes. Safe induction of general anesthesia in patients with heart failure can be accomplished in a wide variety of ways. A variety of anesthetic drugs can be selected on the basis of both their anesthetic properties and their hemodynamic effects. However, one must realize that essentially all intravenous and inhalational anesthetics can initiate profound (dose-related) cardiorespiratory depression. Additionally, the anesthesiologist should thoroughly understand the patient’s underlying cardiac status (left ventricular function, extent of valvular disease, etc.) prior to induction of general anesthesia because specific choices of anesthetic drugs may be determined by specific physiologic goals in individual patients (for example; avoidance of arterial vasodilation in a patient with aortic stenosis). Most commonly, a combination of intravenous opioid (analgesia), intravenous benzodiazepine (amnesia), and inhalational anesthetic (analgesia and amnesia) is used. Following induction of general anesthesia, the trachea is intubated with a cuffed endotracheal tube (following administration of an intravenous muscle relaxant). The choice of a particular muscle relaxant is based upon pharmacokinetics (speed of onset, half-life, etc.) and autonomic and hemodynamic side effects. In most patients, tracheal intubation is accomplished via direct laryngoscopy. However, in patients with altered airway anatomy, tracheal intubation must be accomplished in another manner (awake fiberoptic, asleep fiberoptic, etc.). Once the airway is secured, mechanical ventilation is appropriately initiated.

Maintenance of general anesthesia involves continued administration of intravenous anesthetics and/or inhalational anesthetics to achieve the goals of analgesia and amnesia (and possibly muscle relaxation). While muscle relaxation during cardiac surgery is not required, it is often achieved for a wide variety of reasons (facilitate endotracheal intubation, limit oxygen consumption, prevent shivering, and prevent unexpected movement during critical periods of the operation). The drawback of continuous muscular paralysis is its interference with somatic signs (movement) of light anesthesia. If cardiopulmonary bypass is used, maintenance of general anesthesia is attained via continued administration of intravenous anesthetics and/or inhalational anesthetics.

With the focus on reducing costs by shortening the length of stay in the intensive care unit, the anesthesiologist in encouraged to design an anesthetic plan that not only fulfills the requirements of general anesthesia (analgesia, amnesia, muscle relaxation, hemodynamic stability, etc.) during intense noxious stimulation intraoperatively, but also allows an appropriately rapid recovery of consciousness and spontaneous ventilation postoperatively. In the uncomplicated case, the goal is to allow tracheal extubation very soon after the patient’s condition is stabilized in the intensive care unit, usually within two to fours hours postoperatively. Hence, there is continuing effort to develop rapid-onset, short-acting anesthetics, opioids, benzodiazepines, and muscle relaxants that allow efficient titration of dose (or infusion rate) according to the individual patient’s needs both intraoperatively and postoperatively.

Potential therapeutic interventions in managing patients with hypotension and/or decreased cardiac output include manipulation of heart rate or rhythm, optimizing preload, optimizing myocardial contractility, and/or optimizing systemic vascular resistance [7, 8]. When managing patients with hypotension and/or decreased cardiac output, the initial important task for the clinician is to appropriately assess the hemodynamic instability to determine the etiologic roles that heart rate/rhythm, preload, myocardial contractility, and/or systemic vascular resistance contribute to the hemodynamic instability. Once the cause (or causes) of hemodynamic instability are identified, the physiologic goal (or goals) are identified and appropriate specific therapy is initiated. Such decisions are clinically important. Appropriate clinical interventions can prove life-saving. Conversely, inappropriate clinical interventions can prove deadly. For example, administering a vasoconstrictor to a patient who has hypotension/decreased cardiac output from left ventricular failure will most certainly precipitate clinical deterioration. This patient requires agents that increase myocardial contractility and/or initiate afterload reduction (not vasoconstrictors). This section will focus on how clinicians should appropriately assess hemodynamic instability, choose the physiologic goal (or goals), initiate appropriate specific therapy, and assess the outcome of the chosen therapy [9, 10].