Medical Image of the Week: Traumatic Aortic Dissection

Figure 1. Chest x-ray demonstrating widened mediastinum with prominence of the aortic arch.

Figure 2. Contrast enhanced CT axial (A, left) and coronal (B, right) views demonstrate descending thoracic aortic dissection with mediastinal hematoma and intimal flap (arrow).

A 21-year-old gentleman with no significant past medical history presented to the emergency department following a highway speed motor vehicle collision. The patient was a restrained passenger in the back seat of the vehicle. On initial evaluation the patient was in stable condition and complaining of acute onset back pain. Physical exam was remarkable for facial contusions, tenderness to palpation about the thoracic and lumbar spine, and a normal neurologic exam.

Imaging with chest x-ray (CXR) revealed widening of the mediastinum with prominence of the aortic arch (Figure 1). Further investigation with contrast enhanced computed tomography (CT) of the chest, abdomen and pelvis showed descending thoracic aortic dissection with mediastinal hematoma (Figure 2). The patient underwent successful endovascular repair and was discharged in stable condition.

Acute traumatic aortic injury is a potentially life-threatening condition requiring prompt evaluation. Initial investigation in the trauma setting often includes CXR imaging (1). CXR findings which should raise suspicion for aortic injury in the appropriate clinical scenario include mediastinal widening, abnormality of the aortic silhouette, and right side tracheal deviation.

CT angiography (CTA) is considered the definitive diagnostic modality in most cases, with high sensitivity and specificity. Mediastinal, periaortic and retrocrural hematoma are findings suggestive of traumatic aortic injury. Definitive findings include contrast extravasation, irregularity of the aortic contour, contained rupture, intramural thrombus, and aortic dissection.

Justin S. Caskey, BS

University of Arizona

College of Medicine

Tucson, Arizona, USA

Reference

1. Nagpal P, Mullan BF, Sen I, Saboo SS, Khandelwal A. Advances in imaging and management trends of traumatic aortic injuries. Cardiovasc Intervent Radiol. 2017 May;40(5):643-54. [CrossRef] [PubMed]

Cite as: Caskey JS. Medical image of the week: traumatic aortic dissection. Southwest J Pulm Crit Care. 2018;16(2):94-5. doi: https://doi.org/10.13175/swjpcc016-18 PDF

Medical Image of the Week: Blue-Green Urine and the Serotonin Syndrome

Figure 1. Panel A: blue-green urine a few hours after parathyroid surgery. Panel B: normal urine color 72 hours post-surgery.

A 56-year-old woman was electively admitted for parathyroidectomy for primary hyperparathyroidism with osteoporosis. Five hours post operatively, she developed acute change in mental status. The neurological exam showed inducible clonus, agitation, diaphoresis, ocular clonus, rigidity and hyperreflexia. The patient met Hunter criteria for the diagnosis of serotonin syndrome by being on citalopram and tramadol with the neurological exam findings (1). The patient had been on the same doses of these medications for years with no recent change in kidney or liver functions. The blue-green urine color was strikingly strange. Reviewing the operation room event records showed that she received a high dose of methylene blue to help identify the parathyroid glands.

Serotonin syndrome has been reported with concomitant administration of methylene blue and serotonin reuptake inhibitors (e.g., SSRIs, SNRIs, tricyclic antidepressants). It is recommended to avoid concomitant use and allow a washout period of at least 4-5 half-lives of the serotonin reuptake inhibitor prior to intravenous methylene blue use (2). Within 72 hours of holding tramadol and citalopram the patient recovered completely.

Huthayfa Ateeli, MBBS and Laila Abu Zaid, MD.

Department of Medicine, University of Arizona, Tucson, AZ USA

References

1. Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med. 2005 Mar 17;352(11):1112-20. [CrossRef] [PubMed]
2. Ng BK, Cameron AJ. The role of methylene blue in serotonin syndrome: a systematic review. Psychosomatics. 2010 May-Jun;51(3):194-200. [CrossRef] [PubMed] 

Cite as: Ateeli H, Azid LA. Medical image of the week: blue-green urine and the serotonin syndrome. Southwest J Pulm Crit Care. 2018;16(2):90. doi http://doi.org/10.13175/swjpcc024-18 PDF