Combined general and spinal anesthesia in an infant with single-ventricle physiology undergoing anorectoplasty for an imperforate anus.

NORECTAL MALFORMATIONS including an imperforate anus occur with an incidence of 1:5,000 live births. Although they may occur as an isolated defect, an association with congenital anomalies in other organ systems is common. Current surgical therapy has evolved to allow a single-stage approach for the correction of a low imperforate anus by using a posterior sagittal anorectoplasty as described by de Vries and Pena 1 in 1982. The procedure is generally performed shortly after birth to avoid the need for and thereby the potential complications related to nonrestorative procedures such as colostomy. 2 However, the ability to provide safe and effective anesthesia for neonates may be complicated by associated malformations in other organ systems. A patient is presented who required anesthetic care for an anorectoplasty after placement of a Blalock-Taussig shunt for palliation of congenital heart disease (CHD), which included a double-outlet right ventricle, left ventricular hypoplasia, and pulmonary atresia. Anesthetic care included a technique that combined general anesthesia and endotracheal intubation with a spinal anesthetic. Although previous reports have shown the efficacy of a combined general and spinal anesthetic technique for cardiac surgery in infants and children with CHD, there is limited information regarding such a combination in infants with palliated CHD undergoing noncardiac surgery. A 3-week-old, 3.6-kg infant presented for anorectoplasty. Review of this patient’s medical record and presentation of this case report were approved by the Institutional Review Board of the University of Missouri. The patient’s past medical history was significant for a term birth and the diagnosis of CHD, which included a double-outlet right ventricle, left ventricular hypoplasia, and pulmonary atresia. The infant was also noted to have a low imperforate anus with a fistula to the scrotom. There was no evidence of bowel obstruction and the fistula drained meconium without difficulty. The decision was therefore made to address the CHD first. The infant was initially supported with a prostaglandin E1 infusion and transported to this hospital for surgical management. On the third day of life, the infant was transported to the operating room and underwent an uneventful right Blalock-Taussig shunt (3.5 mm), which was performed through a median sternotomy without the need for cardiopulmonary bypass. Anesthetic management included fentanyl (10 g/kg), ketamine (2 mg/kg), sevoflurane (0.5%-1%), and pancuronium. The infant’s trachea was extubated on day 5 of life (postoperative day 2). On day 17 of life, the infant was transported to the operating room for the anorectoplasty and routine monitors were placed. The oxygen saturation (SaO2) measured by pulse oximetry was 84% on room air. Baseline hemodynamic parameters for the 12 hours before the surgical procedure included a heart rate of 124 to 166 beats/min and a blood pressure of 52 to 74/36 to 44 mmHg. After preoxygenation, atropine (0.1 mg), fentanyl (2 g/kg), ketamine (0.5 mg/kg), and mivacurium (0.2 mg/kg) were administered, and the infant’s trachea was intubated. Maintenance fluids during intraoperative care included continuation of the parenteral alimentation solution containing 25% dextrose in an amino acid and electrolyte solution at 15 mL/h. Cerebral oxygenation measured by near-infrared spectroscopy varied from 55% to 60%. The infant was turned into the left lateral decubitus position, and, after sterile preparation, a lumbar puncture was performed at L4-5 by using a 1” styletted, 22-G spinal needle. After free flow of cerebrospinal fluid was obtained, a solution containing 4 mg of tetracaine and 15 go f preservative-free morphine in an epinephrine wash was injected without difficulty. The preservative-free morphine was prepared by the dilution of 0.1 mL of 1 mg/dL solution and diluting it to 1 mL, thereby providing a solution containing 10 g/0.l mL (0.15 mL of this solution was added to the 4 mg of tetracaine— 0.4 mL of a 1% solution). The infant was turned supine and placed in the lithotomy position. With the change in the position, the infant moved his arms, but no movement was noted in the lower extremities. Anesthesia was maintained with sevoflurane (expired concentration, 0.2%). The surgical incision was made without hemodynamic changes. No clinically significant changes in heart rate, blood pressure, oxygen saturation, or cerebral oxygenation were noted during the procedure. Heart rate varied from 132 to 156 beats/min, blood pressure from 54 to 72/36 to 46 mmHg, cerebral oxygenation from 58% to 66%, and oxygen saturation from 81% to 90%. The infant remained comfortable during the procedure and maintained spontaneous ventilation, which was assisted throughout the surgical procedure. The surgical procedure lasted 140 minutes, and, at its completion, the sevoflurane was discontinued and the infant’s trachea extubated. The estimated blood loss for the procedure was 3 mL. Fluid administration included 35 mL of the parenteral alimentation solution and an additional 40 mL of lactated Ringer’s solution for the replacement of estimated third space and insensible losses. The infant was transported to the pediatric intensive care unit with supplemental oxygen of 1 L/min via a nasal cannula, which maintained an SaO2 of 80% to 90%. The supplemental oxygen was weaned over the initial 12 postoperative hours. No additional analgesia was required until 18 hours postoperatively. The postoperative course was uneventful, and the infant was discharged home on postoperative day 9.