Pulmonary Hypertension in Pregnancy
Abstract Number: 70
Abstract Type: Case Report/Case Series
A 27 year old G3P2 at 29 weeks gestation presented to our academic medical center with a known adnexal mass. This previously healthy patient was experiencing dyspnea and orthopnea and was found to have an increasing O2 requirement necessitating ICU stay at a community hospital. At that hospital, a 21 cm mass was diagnosed and echocardiogram revealed a depressed EF of 40%. After much discussion amongst the gynecologist-oncologist, obstetrician, perinatologist, and anesthesiologist the patient was transferred to our facility for biopsy versus tumor resection. In addition to her gravid status other anesthetic concerns were new onset heart failure and unexplained continued hypoxia. Due to the apparent aggressive nature of the tumor, we proceeded despite the elevated anesthetic risk.
The patient was induced via rapid sequence technique and fetal heart tones were monitored. Upon placement of the PA catheter, elevated PAS pressures were noted ranging from 39-59. Exploratory laparotomy proceeded uneventfully with removal of the mass. Maternal vitals remained stable. Fetal bradycardia was noted with emergence. It appeared to be due to uterine hypertonicity. A dose of terbutaline was given with subsequent relaxation and return of FHTs to baseline. The patient was extubated. Minutes after extubation the patient had a subsequent sustained uterine contraction with sustained fetal bradycardia. The patient was emergently reintubated and emergency C-section performed. The viable infant was intubated and taken by the NICU team.
Pulmonary hypertension (PAH) in the obstetric population has not been well described. PAH is due to an increase in pulmonary vascular resistance, eventually leading to cor pulmonale and death. The pathophysiology involves small pulmonary artery remodeling which leads to proliferation of smooth muscles and ultimate obstruction of pulmonary arteries. Other factors that lead to obstruction of the small pulmonary arteries can also cause PAH, i.e. lupus, amniotic fluid embolism, or thromboembolism. This patient was at increased risk of thromboembolism due to both her gravid status and neoplastic process causing a hypercoagulable state.
A rare cause of PAH is pulmonary tumor thrombotic microangiopathy (PTTM). The features of PTTM are widespread tumor emboli of the small arteries and arterioles of the lung. Tissue factor and vascular endothelial growth factor have been implicated in studies. The most frequent neoplasm associated with PTTM is gastric cancer. Lesions from other organs have been identified; however, there are no case reports of colon adenocarcinoma.
Two weeks after discharge, she was readmitted with an obstructed bowel. Further work up found the primary site of adenocarcinoma to be colon. Unfortunately, advanced colon cancer in young women has a poor prognosis. She has been undergoing chemotherapy for five months, but has been counseled by her oncologist that these treatments are only palliative.