A 10-year-old girl from the Liangshan prefecture in Sichuan Province, Qinghai−Tibet Plateau, China, presented to hospital with cardiac murmurs for 6 years. She was diagnosed with DORV and advised to undergo surgical treatment 6 years ago. However, she was unable to have the surgery because of economic reasons. Her situation progressive worsened, and she was eventually admitted to our center.
Her physical examination revealed delayed growth (height, 119 cm; weight, 19 kg), a blood pressure of 94/65 mmHg, a pulse rate of 98 beats per min, and a respiratory rate of 24 breaths/min. Her baseline oxygen saturation is maintained at about 80%. Blood tests showed a Hb of 24.8 g/dL, hematocrit (Hct) of 75%, mean corpuscular volume of 93.3 fL, mean corpuscular Hb of 31 pg, mean corpuscular Hb concentration of 33.2 g/dL, and a platelet count of 108 × 109 cells/L. Her blood coagulation test was also abnormal, with a prothrombin time of 16.7 s, active partial thrombin time of 61.8 s, and an international normalized ratio of 1.51. Other blood tests showed no significant abnormalities. Transthoracic echocardiography (TTE) revealed a DORV, a ventricular septal defect (VSD) with a bidirectional shunt at the ventricular level, an atrial septal defect (ASD) with a right-to-left shunt at the atrial level, severe pulmonary valve stenosis, right ventricular hypertrophy, and transposition of the great arteries, but with normal left ventricular functions (ejection fraction, 66%) (Fig. 1). Chest radiography demonstrated abnormal cardiac morphology (Fig. 2), while chest computed tomography showed a DORV with a VSD, an ASD, subvalvular pulmonary artery stenosis and transposition of the great arteries. (Fig. 3). Right cardiac catheterization was performed after admission. Angiography showed normal distal pulmonary artery development, and multiple aorta pulmonary collateral arteries, two of which were successfully occluded during the procedure. The mean pulmonary artery pressure was measured as 13 mmHg. Considering normal distal pulmonary artery development, normal left ventricular function and acceptable pulmonary vascular resistance (PVR), a modified Fontan operation was then planned.
Anesthesia And Surgery
General anesthesia was selected because of the patient’s severe and complicated condition. Routine monitoring was performed. After anesthesia, induction was performed with sufentanil (12.5 µg), midazolam (1.5 mg), and cisatracurim (6 mg), and the patient was smoothly intubated without a marked decrease in oxygen saturation. The radial artery and internal jugular vein were then catheterized to monitor blood pressure and central venous pressure (CVP), respectively. Continuous transesophageal echocardiography (TEE) examination was performed to assess cardiac function and volume status throughout the procedure (Fig. 4). Anesthesia was maintained with sevoflurane (1%−3%), propofol (2−6 mg/kg/h), and remifentanil (0.1−0.2 µg/kg/min). Intraoperative mechanical ventilation strategies included a tidal volume of 6−8 mg/kg, and maintaining an end-tidal CO2 between 25−30 mmHg.
After induction, preoperative hemodilution was performed by infusion of crystalloid solution (350 mL) over 1 h to decrease blood viscosity and prevent thrombotic complications. Tranexamic acid was administered before incision to inhibit the fibrinolytic process and prevent bleeding. Crystalloid solution and human albumin was also added to priming solution used for cardiopulmonary bypass (CPB) to further dilute circulating red blood cells. Hct was maintained at 45–55% in the CPB. A fenestration modified Fontan operation was performed. After performing a total cavapulmonary connection, the surgeon implemented a right atrium fenestration about 3 millimeter. The surgical procedure was uneventful. The left atrium was then catheterized to continuously assess left atrial pressure prior to discontinuing CPB. After discontinuing CPB, sufficient blood volume (based on dynamic TEE monitoring and blood gas analysis) and a higher CVP were maintained to provide adequate preload for the right ventricle, to facilitate blood flow towards the pulmonary circulation. The patient received 670 mL of crystalloid solution, 200 mL of plasma, 1 unit of platelets, and a 300-mL transfusion of autologous recovered blood.
The patient was then shifted to the intensive care unit (ICU). Fortunately, postoperative bleeding was mild and she continuously administered plasma and platelets to correct coagulation disorder. Changes in Hb levels and coagulative function are shown in Table 1. In ICU, the patient was placed in a head-high position to facilitate vena cava reflux. Tracheal tube was extubated on postoperative day 1, and she was adopted thoracentesis and drainage on postoperative day 2. Considering that she was in a stable condition and no complications occurred, the patient was transferred to general ward on postoperative day 4 and was discharged on postoperative day 7.
Table 1
The variation of Hb and coagulation function
Variables | Preoperative | Postoperative day 1 | Postoperative day 4 | Postoperative day 8 |
Hgb (g/dL) | 24.8 | 16.7 | 15.7 | 15.3 |
PT (s) | 16.7 | 18.6 | 29.7 | 15.5 |
INR | 1.51 | 1.70 | 2.77 | 1.4 |
APTT (s) | 61.8 | 56.9 | 51.6 | 43.8 |