S4310 Redefining Mallory-Weiss Tears: A Case of Life-Threatening Anemia and Hypoxic Respiratory Failure

Introduction: Hypoxic respiratory failure is defined by arterial oxygen tension (PaO₂) below 60 mmHg on room air. It commonly results from pulmonary conditions such as pneumonia, embolism, or acute respiratory distress syndrome. Less frequently, systemic issues like hemorrhagic shock impair oxygen delivery due to reduced hemoglobin and perfusion. Mallory-Weiss tears (MWTs) are longitudinal mucosal lacerations at the gastroesophageal junction, often caused by vomiting or retching. While often linked to alcohol use, MWTs can occur in other populations and cause significant upper gastrointestinal (GI) bleeding. Case Description/Methods: An 81-year-old woman with a history of gastroesophageal reflux disease, cerebral infarct 6 months prior on apixaban who presented to the emergency department with stroke-like symptoms. Enroute to the hospital, she became hypoxic and was intubated. In the emergency department, her hemoglobin was found to be 2.8 g/dL. Her anion gap was 33 mmol/L. Two units of packed red blood cells were ordered. Arterial blood gas showed a pH of 6.95, PCO2 of 36, PO2 of 139, and bicarbonate level of 8 mmol/L, with fractional inhalation of oxygen (FIO2) of 100 and positive end expiratory pressure of 8. Apixaban was reversed with balfaxar, and desmopressin was given for aspirin use. Lactic acid was elevated at 8.1 mg/dL. She was started on a pantoprazole for presumed upper GI bleeding. Four units of packed red blood cells, 2 units of liquid plasma, 1 unit of cryoprecipitate and platelets were ordered. Computed tomography of the abdomen and pelvis without contrast was unremarkable. She was transferred to the intensive care unit and started on norepinephrine. The NG had coffee-ground drainage. The following day, the patient underwent esophagogastroduodenoscopy which showed a MWT. She was extubated on day 3 of hospitalization and discharged on day 11. Discussion: This case highlights the need to consider non-pulmonary causes of hypoxic respiratory failure. Severe anemia from a MWT impaired oxygen delivery, despite adequate ventilation and normal lung findings. The absence of overt GI bleeding signs delayed diagnosis. Hypoxia in this case was driven by reduced oxygen-carrying capacity rather than primary lung pathology. In patients with unexplained hypoxia and hypotension, clinicians must consider occult bleeding. Endoscopic evaluation enabled timely diagnosis and intervention. This case demonstrates how identifying non-pulmonary contributors to hypoxia is essential, and how prompt hemostasis and hemoglobin restoration can reverse respiratory compromise.