Call the plumber!

Life is different on the countryside. The hospital lies just up a hill surrounded by forest. A couple of wards, a small but handy emergency department, and a few operating theaters keep things running. Chief complaints includes “Hit self with axe”, “Tractor accident/MVA” – type of injuries in addition to the usual bread and butter of the ED.

A 63-year old male was brought in by ambulance complaining of left-sided groin pain. The paramedics suggested a short episode of hypotension which had resolved by the time of arrival to the hospital. Apart from Barrett’s esophagus, the patient had a clean bill of health. He was a farmer by occupation working at a field overseeing the countryside.

The pain was described as acute in onset, severe, sustained, and neither alleviated nor exacerbated by motion. No radiation was present, but the pain had partly migrated to the left foot. When asked explicitly, an episode of severe chest pain had been present in the ambulance. Even though milder, it was in fact still present at the moment of examination!

Vital signs: HR 98, BP 120/70, spO2 94% on room air. Respiratory rate 24. Temp 37,1
General: In mild distress, reports moderate pain. GCS 15.
Heart: No murmur, abnormal loud S1, S2.
Lungs: Normal breathing sounds, no rales/rhonchi.
Abd: Soft but tender in left lower quadrant.
Peripheral pulses: R/L radial pulses present, L pedal pulse absent.

With a history of multifocal, severe pain, as in this case chest, groin and left leg, what is one to suspect? What is the likely diagnosis and what would you do next?

Aortic dissection (AD), the haunting diagnosis that keeps us up at night, must be suspected upon the features of severe pain from several body compartments and pulse abnormalities (aka North South symptoms).

AD carries a high mortality which is highest during the first 48h, implying the need for a high index of suspicion and rapid diagnostic pathways. [1] Mortality in type A dissections increases by 1-2% for every hour of delayed intervention.

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Pain that is severe and sudden in onset presents in about 80% of AD cases. Pulse abnormalities often sought for, are estimated to be present in only 30% of patients making it an unreliable diagnostic tool. [2]

Cardiac complications often accompany a proximal aortic dissection (Type A by Stanford classification). Evaluation must be done for the presence of severe aortic regurgitation, pericardial hemorrhage, tamponade, and even myocardial infarction caused by coronary involvement. The right coronary artery is more frequently involved in such cases. [3]
Intimal flaps may be present and found throughout all of the aorta and its major branches, and hence produce a variety of symptoms from different body organs. Neurological presentations are not rare and may be present in 15-40% of cases, sometimes even producing spinal ischemia from occlusion of spinal vessels. Any severe pain accompanied by neurological deficits should raise the suspicion of AD. [2]

Under certain circumstances ultrasound may reveal the direct or indirect effects of this pathology. The sensitivity of detecting an AD with transthoracic ultrasound by an experienced sonographer may be as low as 77% and should not be used as a rule-out method, especially not in the bedside setting. [2] Gold standard is contrast-enhanced computed tomography.

D-dimer has been proposed as a rule out-test for AD. However, evidence suggests that sensitivity is too low for a lethal condition such as AD, especially when pretest probability is already high per history and physical examination findings. [4]

Our patient was taken immediately to CT as the treating physician had an high suspicion of AD.

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CT aorta showed an extensive type A dissection from the aortic valve down to the left iliac artery with occlusion of the iliacs and subtotal occlusion the superior mesenteric artery. Blood pressure and pulse-rate should be monitored frequently. Generally, a reduction in afterload alone will produce a compensatory chronotropic boost, which could increase wall stress. Therefore it is recommended to use a mixed alpha/beta adrenergic antagonist, such as labetalol (Trandate). [1]

The patient was transported by ambulance to a tertiary care center where surgical repair was performed. Perioperatively, the aortic root was found to be severely affected with intimal rifts near both coronary vessels in addition to severe aortic regurgitation. A small amount of hemopericardium was noted. A biological aortic valve and composite graft of the ascending aorta was placed.

Thanks to J.A.K for contributing to the blog!

1. Nienaber C.A. Management of acute aortic dissection. Lancet. Feb 2015 28;385(9970):800-11. doi: 10.1016/S0140-6736(14)61005-9

2. 2014 ESC Guidelines on the diagnosis and treatment of aortic diseases Eur Heart J 2014;35:2873-2926 – Eur Heart J doi:10.1093/eurheartj/ehu281

3. Manning W.J. (2013). Clinical manifestations and diagnosis of aortic dissection. UpToDate. Retrieved from http://www.uptodate.com/home/index.html

4. Sutherland A, et al. D-dimer as the sole screening test for acute aortic dissection: a review of the literature. Ann Emerg Med. Oct 2008;52(4):339-343