Perioperative Management of Cerebral Protection of an Acute DeBakey Type 1 Aortic Dissection with Stroke in Evolution
Christian Barotti MD, Yong G. Peng MD, Ph.D.
Department of Anesthesiology, University of Florida, Gainesville, FL
Case Report: A 66-year-old black male with a long-standing
history of hypertension presented with some vague upper
abdominal pain. A CT scan demonstrated a widened mediastinum.
Upon further work up, the patient was diagnosed with acute
DeBakey type 1 aortic dissection. He was air-lifted to our
institution for definitive management. Approximately six hours
after initial diagnosis, the he arrived in the operating room in
a combative state, with an 18 gauge peripheral IV on the right
upper extremity and a 20 gauge left radial arterial line in
place. Right upper extremity pulses were not palpable.
Due to the emergent clinical situation, the surgeons agreed to
proceed with anesthetic induction. Arterial blood pressure was
110/70 mmHg accompanied by sinus tachycardia with a rate of 130
beats/min. During preoxygenation, a two-channel bipolar
electroencephalogram demonstrated a pattern consistent with
burst suppression, and a low bifrontal regional cerebral
oximetry reading was recorded at 33. Anesthetic induction was
initiated with a titration of midazolam 5mg, fentanyl 1000mcg,
lidocaine 80mg and succinylcholine 100mg. The patient was
intubated with cricoid pressure without difficulty, relaxed with
pancuronium 8mg. As positive pressure ventilation was initiated,
he became hypotensive and SBP drifted down to 50-60 mmHg. The
patient was placed in the Trendelenburg position, followed by
titration of CaCl 500mg, phenylephrine 120mcg and aggressive
fluid resuscitation. Mean arterial pressure was maintained
around 60mmHg to avoid progression of the aortic dissection.
Using ultrasound guidance, a 9 French introducer and 12 French
double lumen catheter were placed in the right internal jugular
vein. Of note, during ultrasound inspection, in addition to the
bilateral carotid dissections, a large pericardial effusion was
noted. Ventilation with low tidal volumes without PEEP was
maintained along with continued fluid resuscitation to maximize
preload. An oximetric pulmonary artery catheter was floated and
a transesophageal echocardiography probe (TEE) was placed. The
initial pulmonary artery pressure (PAP) was 50/35 mmHg with a
central venous pressure (CVP) of 35 mmHg. TEE confirmed
significant pericardial effusion, a thick ventricle but no
coronary artery involvement. Femoral-femoral cardiopulmonary
bypass (CBP) was initiated prior to sternotomy to avoid
uncontrolled bleeding. Upon drainage of the pericardial effusion
PAP and CVP decreased to 18/8 and 7 mmHg, respectively. Cerebral
oximetry readings increased to 51, and the
electroencephalographic activity increased. Dopamine, mannitol
and furosemide were utilized during the surgery in an attempt to
preserve the renal function. The patient underwent replacement
of the ascending aorta and aortic arch utilizing deep
hypothermic circulatory arrest for 22 minutes and retrograde
cerebral perfusion. The total CBP time was 157 minutes. He was
transferred to CICU in stable condition on dopamine
2mcg/kg/minute and NTG 3 mcg/kg/minute with return of a right
upper extremity pulse.
Unfortunately, the patient’s post-operative course was
complicated by two episodes of bleeding requiring mediastinal
exploration, a small bowel resection for necrotic bowel, and
acute renal failure requiring hemodialysis. He was extubated 9
days after the initial operation and was discharged to a local
rehabilitation center 32 days after initial aortic dissection
repair for further recovery. Upon discharge, he was alert,
oriented demonstrating minimal left lower extremity weakness.
Discussion: The perioperative neurological monitoring and
cerebral protection continue to pose significant challenges to
anesthesiologists who care for patients with acute type 1 aortic
dissection. In order to minimize their postoperative
neurological sequelae, the perioperative anesthetic monitoring
and management for this high risk patient population will be
discussed.
