Aortic Dissection
Presentation:
T.G. is a 71 year old female with a known history of an AAA who presented to the ED with extreme anxiety, leg numbness, severe tearing chest pain, hypertension, tachycardia, and nausea. A CT scan was immediately obtained which showed a descending and ascending aortic dissection from the roots of the aorta to the bifurcation of the iliac arteries. She was emergently taken to the OR. The surgery began at 1230 in the afternoon and ended at 0820 the next morning. In the OR they were able to repair the ascending dissection but the patient was still bleeding. No surgical source of bleeding was identified so the bleeding was deemed medical, presumably DIC. The chest was left open but a silo type material was stapled around the open chest wound and an Ioban dressing to cover the chest and tubes. The patient was also placed on ECMO and was cannulated in the subclavian artery and the right atrium. The ECMO was running at 7250 RPM for a blood flow of 5.3 LPM. A lumbar drain was also inserted to keep the pressure 7-10 mmHg to ensure that the spinal cord was being perfused. Upon arrival to the ICU, the patient had received 122 units of blood products like PRBCs, FFP, platelets, and cryo in the OR and was still bleeding profusely from the Blake drains and chest tubes. She continued to put out roughly 700-800 ml of frank blood from her drains every hour, her silo dressing was bulged-over the open chest wound and it was leaking large pools of blood around her, heart sounds were muffled, PA catheter numbers become narrow, the ECMO was alarming “low flow”, and we lost a pulsatile flow on the arterial BP measuring line. Her chest dressing was emergently opened at the bedside to “scoop” out the large clots forming in the gaping incisional wound. Ongoing transfusions were necessary as well. Also, DP pulses were absent and the feet were demarcated and dusky.
WBC: 2.34, H/H: 6/19, Plt: 126,000, PT/PTT: 35/56, INR: 2.12
pH: 7.12, PaCO2: 45, PaO2: 266, HCO3: 15, Lactate: 19
CPK 3000, CPK-MB 35.16, Troponin: 42
Ionized Ca : 0.89, K+: 4.2
Diagnosis:
Ascending and Descending Aortic Dissection
Treatment:
The pt was taken to Interventional Radiology to fix the descending dissection and restore flow distally. The ischemic tissues were the major contributors to the high lactate. Also, bilateral fasciotomies were done to treat the compartment syndrome now that flow was restored distally. Also, 3 doses of regular insulin (10 units) and 1 amp of D50 were given for persistent potassium level above 7, now that tissues were being perfused. Also, multiple doses of calcium chloride, instead of calcium gluconate, due to expected liver damage, were given. CVVH, a continuous form of dialysis, was ordered once back to the unit to treat the high K+ levels. An additional and astounding 84 more units of blood products were given.
Outcome:
The patient died from overwhelming shock, DIC, etc.
Case created by Theresa Ganoe, 2010.