Pheochromocytoma in a woman with monochorionic twin pregnancy complicated with twin to twin transfusion syndrome: a case report
Abstract Number: SU-60
Abstract Type: Case Report/Case Series
A 25-year-old primigravida at 16 weeks gestation of monochorionic diamniotic twin presented with intractable high blood pressure. Urinary vanillylmandelic acid and normetanephrine revealed elevated norepinephrine. Abdominal ultrasonography identified right adrenal tumor. Diagnosis of pheochromocytoma was confirmed at 19 weeks gestation. Magnetic resonance imaging indicated the possibility of the adhesion between the mass and inferior vena cava. Laparoscopic resection of the tumor was considered, but her large uterus and the location of the mass precluded the laparoscopic surgery. Our plan was to delay surgical resection until the postpartum period. Doxazosin 1mg per day was started, but switched to prazosin due to pruritus one week later. The dose of prazosin was increased to the maximum after 5 weeks. Her blood pressure ranged from 110/70 mmHg to 130/90 mmHg at that time. At 28 4/7 weeks gestation, twin-to-twin transfusion syndrome developed. Urgent Cesarean section was planned. Because her hemodynamics was well controlled, we selected combined spinal-epidural anesthesia with arterial line and central line monitoring. When she changed her position before regional block, her blood pressure went up to 190 mmHg. Phentolamine was administered against sudden hypertension. During operation her heart rate increased to 110 bpm. Landiolol hydrochloride, short acting beta blocker was injected continuously. Neonates, weighting 845g and 945g were delivered in good condition. The patient stayed in the ICU overnight for hemodynamic monitoring and pain control with PCEA. She resumed prazosin the next day. Her hemodynamics was almost stable postpartum, and she was discharged home after 18 days. Resection of pheochromocytoma is planned at months postpartum.
Pheochromocytoma in twin pregnancy is extremely rare. Since there is no established course of treatment with regard to the timing of resection and delivery, and surgical procedure, we should provide optimum anesthetic management according to each case. A close co-ordination among multidisciplinary team is the key to safer management. Prenatal diagnosis is sometimes difficult, as its symptoms often resemble those of severe preeclampsia. The timing of surgery is controversial. There are case reports of laparoscopic resection before 24weeks’ gestation, followed by vaginal delivery at term. In our case, although pheochromocytoma was detected before 24 week gestation, we chose conservative management due to larger uterus with twin. The massive tumor was located in adjacent to IVC, thus we chose not to resect the tumor right after CS. Early diagnosis and preoperative preparation, as well as strict intraoperative hemodynamic control results in good maternal and fetal outcomes.