Chief complaint: leg and back pain.
As you enter the room you see a 63 y/o male lying still on the cot, grimacing in pain, slightly diaphoretic. His history is limited because of his pain and he provides only minimal responses to questions.
While walking down the street he started to have an aching in his back that progressed down his leg. This was about one hour ago. The pain continued to get worse, and now the pain is severe. The location of the pain is his lumbar back area and his entire left leg. Movement does not make the pain worse. No history of previous similar symptoms.
ROS: No fevers, chills, nausea, vomiting, diarrhea, headache, rashes. He did note some chest pain earlier, and took two nitroglycerine tabs and it eventually went away. No chest pain now. No shortness of breath, cough. No abdominal pain, no dysuria.
PMH: Heart attack 2 years ago (1 stent), HTN, diet controlled diabetes.
SH: Smoker for >40 years; Social alcohol.
PE: Very anxious, diaphoretic man, wincing in pain. (He appeared so uncomfortable that before I finished obtaining a history, I left to ask a nurse to start a line and give him 10 mg of morphine).
BP: 165/100, RR 24, HR 90, Temp 98Fpo
HEENT: Unremarkable, no JVD
Heart: RRR, no murmurs
Lungs clear bilateral
Abdomen: Soft, some tenderness is noted in the periumbilical area. No scars. No distension.
Ext: Upper extremities normal. Left lower leg cool to touch. It is pale, and there is no palpable pulse at the dorsalis pedis, posterior tibialis, or popliteal area. There is a very faint pulse at the femoral area that is obtained only by Doppler. Right leg has easily palpable pulses throughout. The left leg is paretic, and the patient can only wiggle toes and lift the leg about 4 inches off the cot for a second before it collapses back to the cot. Decreased sensation to the entire leg is also noted.
1. What is the diagnosis, and what is one potential etiology?
Clearly this patient has the five P’s of an arterial occlusion (pain, pulseless, palor (pale), parasthesia, paralysis). Diagnosis of the acute arterial occlusion is easy; the real challenge is why is his artery occluded? The most common causes of acute arterial occlusion is thrombosis of a lower extremity bypass graft or in situ thrombosis of a native arterial segment. (1) In this patient, it seems the whole leg is involved. Additionally there is the abdominal tenderness and chest pain he reluctantly noted earlier. Together is raises some concerns about his aorta (either aneurysm or dissection).
2. Can ultrasound help here?
Yes, ultrasound can easily visualize the aorta (unless the patient is severely obese, or there is overlying gas). Bedside ultrasound can diagnose Abdominal Aortic Aneurysms (AAA) and even dissections. (2). In this case, I was more worried about an AAA because of the complaints of severe back pain, but when I did the ultrasound, I could easily see the dissection flap on the bedside ultrasound. That’s when I obtained the information about the chest pain earlier. Initially when I asked him he denied chest pain (he wasn’t having any chest pain when I first asked him….so he initially answered “No” to my chest pain question. It’s only when I asked if he had any chest pain today that he described the chest pain earlier).
Using bedside ultrasound helped me quickly determine the cause of this patient’s pain. For a great teaching library of Emergency Medicine Ultrasound, check out this free link: “http://www.sonoguide.com“. It’s full of great images and teaching points. It even has information and scans for the less common ultrasounds: testicles and orbits.
There are several different classifications for dissections. The easiest one for me to remember is Sanford type A (includes the ascending aorta) and Sanford type B (doesn’t include the ascending aorta). (3)
Management of the two types of dissections is different. In general, Type A dissections usually require surgery, while Type B can be managed medically (blood pressure and pulse control), unless there are complications. Complications to Type B dissections making surgery a consideration include: compromise of a vital organ, rupture (or impending rupture) of the aorta, retrograde dissection into the ascending aorta, or a history of connective tissue disease (Marfans or Ehler-Danlos Syndrome) (3).
3. What are your orders and who you gonna call?
This patient clearly falls into the ‘sick’ category so he gets the usual six things (that sick people get): IV (2 lg bore in this case), Oxygen (in case he deteriorates and needs intubation), monitor, completely undressed, frequent vital signs, and blood tests (Type and Cross for 4, basic metabolic panel, coagulation profile, CBC, Cardiac panel). I also ordered a CXR. EKG, CT chest/ABD/pelvis. Additional orders included decreasing the blood pressure and heart rate, and for this patient Labatolol worked great. Pain control can also help blood pressure.
I first called the vascular surgeon because of the arterial occlusion at the level of the femoral artery, but when we found it was a Type A dissection a cardiovascular surgeon was needed to repair the tear in the chest (at the origin of the dissection).
CT of the chest/Abd/pelvis revealed the dissection was a Sanford A. He was admitted to the hospital and ultimately died later that day. After the diagnosis, the lactate came back at 16, so we knew his mortality rate was very high.
1. Ouriel, K. Acute Arterial Occlusion. Current Treatment Options in Cardiovasular Medicine. May 2000. 2(3):255-264 Accessed at: “http://www.springerlink.com/content/e713lvw8337j2688/”
2. Fojtik JP, Costanino TG, Dean AJ. The Diagnosis of Aortic Dissection by Emergency Medicine Ultrasound. J Emerg Med. 2007 Feb; 32(2):191-6. Accessed at: ”http://www.ncbi.nlm.nih.gov/pubmed/17307632?ordinalpos=7&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum”
3. Wikipedia. Aortic Dissection. Accessed at: “http://en.wikipedia.org/wiki/Aortic_dissection“