Superior mesenteric artery syndrome associated with recurrent aspiration and difficult ventilator liberation in a post-trauma patient: a case report

Abstract Background Superior mesenteric artery syndrome (SMAS) is an uncommon cause of proximal intestinal obstruction caused by compression of the third portion of the duodenum between the superior mesenteric artery and the aorta. Recurrent vomiting can result in aspiration and respiratory deterioration. We report SMAS as a potentially reversible gastrointestinal contributor to recurrent aspiration and repeated difficulty in ventilator liberation in a critically ill post-trauma patient. Case presentation A 19-year-old Saudi male with severe traumatic brain injury after a road traffic accident was transferred for prolonged ventilatory care after craniectomy, ventriculoperitoneal shunt placement, right elbow fixation, and tracheostomy. At transfer, his Glasgow Coma Scale score was 7/15; height was 167 cm and weight 70 kg (BMI 25.1 kg/m²). During approximately 12 months of ventilator dependence, five attempts to transition from pressure-regulated volume control (PRVC) to continuous positive airway pressure (CPAP) failed after episodes of vomiting followed by aspiration pneumonia, documented by new chest-radiographic opacity and increased ventilatory requirements. Chest and abdominal radiographs demonstrated marked gastric distension. Contrast-enhanced abdominal CT in November demonstrated compression of the third part of the duodenum at the aortomesenteric region with severe proximal gastroduodenal dilatation. Retrospective review showed a narrowed aortomesenteric angle of approximately 20–25° and a minimum aortomesenteric distance of approximately 7 mm. Approximately one week after diagnosis, a jejunal extension was placed endoscopically through the existing PEG (PEG-J) beyond the obstructed segment. Vomiting ceased, and the patient was liberated from mechanical ventilation within one week. He remained off ventilator support for one year of follow-up, with no recurrence of vomiting. Conclusions In neurologically impaired or post-trauma patients with persistent vomiting, marked gastric distension, recurrent aspiration, or otherwise unexplained difficulty in ventilator liberation, SMAS should be considered among reversible extrapulmonary contributors. An enlarged stomach on routine chest radiography is nonspecific but may prompt definitive abdominal imaging. In selected patients, post-pyloric feeding through a PEG-J can bypass the obstruction and control vomiting. The temporal association between cessation of vomiting and durable ventilator liberation in this case supports contribution from SMAS but does not establish sole causality.