RAPIDLY EXPANDING ANTERIOR MEDIASTINAL MASS IN A PREGNANT PATIENT
Abstract Number: 113
Abstract Type: Case Report/Case Series
Anesthesia for obstetric patients carries inherent risks largely related to exacerbation of pre-existing cardiovascular, pulmonary and neurologic diseases. Anterior mediastinal masses also carry inherent risks in the setting of general anesthesia and it is with these two conditions that our patient presented to the operating room for elective cesarean section at 31 weeks gestation.
At 29 weeks gestation our 28 yo G1P0 patient with history of Neurofibromatosis Type I was found to have a 10-cm mass located on the left side of the anterior mediastinum. Three weeks prior to arrival in the operating room she underwent work-up including CT scan, PET scan and transthoracic echocardiogram that showed a 10 x 7 x 10 cm mediastinal mass partially compressing the left main pulmonary artery as well as causing deviation of mediastinal structures to the right. Echocardiography showed moderate pericardial effusion. In the short period following her initial consultation the mass enlarged significantly and caused worsening of her symptoms including cough, fatigue, shortness of breath and orthopnea. Physical exam showed a cachectic female with a gravid abdomen propped up on two pillows in mild distress. Trachea was midline. Auscultation of the chest revealed clear breath sounds and unremarkable cardiac exam. She was brought to the operating room and positioned in reverse Trendelenberg with left uterine displacement. Minimal sedation was given through a pre-existing 18-gauge peripheral intravenous catheter during awake arterial line placement. She was preoxygenated while being prepped and draped for surgery, and induction was completed with ketamine, fentanyl and midazolam. The trachea was intubated without difficulty by direct laryngoscopy after administration of succinylcholine. There were no anesthetic complications and the patient and newborn both tolerated Cesarean section well.
Patients with anterior mediastinal masses present a challenge due to possible risk of tracheal or bronchial compression, compression of the heart or compression of large blood vessels. These situations may not come to light until spontaneous respirations are ceased, the patient is supine or general anesthesia is induced. These risks are especially concerning in a pregnant patient not only due to status of mother and fetus, but also because of alterations in pulmonary and cardiac status inherent in pregnancy. Risk factors associated with intraoperative complications include pericardial effusion, which was present in our patient. Postoperative complications are more often due to tracheal compression >50% and mixed pulmonary syndrome on pulmonary function tests.