Case 2—1996 Anesthetic management of a patient with hemoglobin SS disease and mitral insufficiency for mitral valve repair*

The patient was a 52-year-old black woman who presented to the Cardiology Service at a US Army medical center for evaluation of progressive dyspnea over the past 2 months. Her symptoms had responded to captopril, 50 mg three times a day, and digoxln, 0.3 mg daily. Evaluation in January 1993 noted atrial fibrillation, cardiomegaly, and chronic obstructive pulmonary disease. Transesophageal echocardiography demonstrated severe left atrial and ventricular enlargement with severe mitral insufficiency and mild aortic insufficiency. Cardiac catheterization showed pulmonary artery pressures of 35/15 mmHg, pulmonary artery occlusion pressure of 18 mmHg, and significant "V" waves noted. Cardiac output was 8.7 L/mln. Left ventracular function and the coronary arteries were normal. Medical illnesses included sickle-cell disease with multiple crises, although none had occurred in the past 2 years, and todd chromc renal insufficiency with a creatinine of 2.1 mg/dL. Hemoglobin was 7.6 g/dL (hematocrlt 21.3%) with marked dysmorphlc and slckled red cells on the smear. There were mild elevations in AST, LDH, and bllirubin levels. Bleeding time was prolonged initially at 10 minutes (nL 5 to 7 minutes) on admission but had normalized to 5 minutes on the day before surgery. Flbrinogen level, thrombin time, prothrombIn time (PT), and partial thromboplastin time (PTT) were all normal. Hemoglobin electrophoresis showed a hemoglobin S fraction of 80%. Because of the rapid progression of cardiac symptoms with relatively well-preserved ventrlcular function and absent coronary artery disease along with the stable sickle-cell disease without evidence of severe end-organ damage, mltral valve repair or replacement was recommended. Rather than preoperative transfusions or partial exchange transfusion, lntraoperatlve red cell exchange and plateletpheresls were performed after the induction of anesthesia before surgical moslon under conditions of normothermla, high oxygen delivery with low oxygen demand, and invasive cardiovascular monitoring. 1,2 The red cell fraction usually returned to the patient during intraoperative plateletpheresls was discarded and replaced with banked red cells to provide an absolute reduction in the hemoglobin S fraction with the added benefit of sequestering fresh autologous platelets and clotting factors to aid in postbypass hemostasls. After premedlcatlon with morphine sulfate, 7 mg, and scopolamine, 0.2 mg, intramuscularly, the patient was placed on the operating table and all pressure points were padded. Pneumatic compression devices were placed on the lower extremities to diminish venous stasis during surgery. Ambient and body temperatures were maintained at normal levels. Noninvasive monitors including electrocardiogram, blood pressure, pulse oximeter, and nasopharyngeal and bladder temperature probes were placed. Two upper-extremity 14-gauge IV catheters and a 20-gauge right radial arterial catheter were placed. A 9F introducer (Burron Medical Co, Bethlehem, PA) was placed in the right internal jugular vein through which an 8F pulmonary artery catheter with fiberoptic mixed venous oxygen saturation capability (Opticath; Abbott Critical Care Systems, Mountain View, CA) was introduced and floated into the pulmonary artery occlusion position. Anesthetic induction was accomplished with midazolam, 2 mg, fentanyl, 50 ixg/kg in divided doses, and vecuronium, 10 mg. An infusion of 2 Ixg/kg/min of dopamine was begun to enhance renal perfuslon. After intubation, a transesophageal echocardiographic probe (HP Sonos 1000; Hewlett Packard Co, Andover, MA) was placed, and baseline hemodynamic and laboratory studies (Tables 1 and 2) were obtained. Hemodynamic data including cardiac output obtained at end expiration (Marquette Electronics Inc, Milwaukee, WI) were recorded. Arterial and mixed venous blood gases were sent for blood gas analysis (Ciba Corning, Medford, MA), and specimens were sent for red blood cell and platelet counts and PT/PTT determinations. Activated coagulation time (Hemochron; International Technidyne Corp, Edison,