Upon completion of surgery, the cardiac patient is transported to the intensive care unit (ICU) for postoperative management. The role of the anesthesiologist or the anesthesiology department in postoperative care depends on institutional policies and procedures. Anesthesiologists trained in intensive care, non-anesthesiologist intensivists, and nurse practitioners in consultation with the patient’s attending cardiac surgeon might manage the ICU care. In other settings, the patient’s anesthesiologist will manage some elements of postoperative care (e.g., ventilation) while the surgeon attends to others (e.g., chest tube management). What must be emphasized for the practitioner new to cardiac anesthesiology is the need to be aware of the operating paradigm used in one’s individual institution. Moreover, it is critically important that anesthesiologists carefully document their report and the time of transfer of care to the ICU team. Unfortunately, some patients survive the intraoperative period only to succumb minutes, hours, or days following arrival in the ICU.
This chapter reviews common problems encountered in the postoperative care of the cardiac surgery patient. It is by no means a comprehensive text on critical care but rather highlights some of the particular problems that appear in routine postoperative cardiac surgery recovery and ICU.
ROUTINE TRANSPORT AND REPORT
Following cardiac surgery, patients are transported fully monitored (ECG, arterial pressure, oxygen saturation) from the operating room to the ICU. As the transport of an unstable patient to the ICU can be challenging, every effort to improve hemodynamic stability should be undertaken in the operating room prior to moving the patient. Anesthesiologists must be prepared for the inadvertent extubation of the patient or the accidental disconnection of a central venous line during transport. Consequently, airway management equipment and redundant intravenous access should be readily available. Similarly, anesthesia providers must be prepared to treat hemodynamic instability. Blood pressure variations are common as patients begin to regain sympathetic tone once anesthetics are withdrawn. Propofol and/or dexmedetomidine infusions, when hemodynamically tolerated, can be used to mitigate the increases in blood pressure often seen in postoperative patients during patient transport. Additionally, dexmedetomidine may reduce the incidence of delirium in ICU patients. Intravenous infusion of nicardipine or other anti-hypertensive agents can also be employed to blunt emergence hypertension. In particular, patients with noncompliant vasculature (common among cardiac surgery patients) will frequently develop severe hypertension during emergence requiring the administration of propofol, narcotics, and vasodilators postoperatively. At the same time, because these patients may be hypovolemic, when hypertension is treated there is often a tendency to overshoot transforming hypertension into severe hypotension.
Patients are routinely transported from the operating room to the ICU with any one of many vasoactive infusions running. Care must be taken to be sure that during transport all expected infusions are flowing at the desired rate and are correctly labeled. As patients awaken, the need for vasoconstrictors such as vasopressin and norepinephrine decreases as vascular tone is restored. Using hemodynamic and echocardiographic guidance, vasoconstrictors, ...