We report the case of an 82-year-old female who presented in a hemodynamically unstable condition to the emergency department of our institution. Transthoracic echo showed a hemodynamically relevant pericardial effusion and the suspicion of an intimal flap in the ascending aorta. The subsequent computed tomography scan revealed a Type A dissection that was limited to the ascending aorta. To prevent hemodynamic deterioration the patient was prepped and draped awake and underwent femoral cannulation for extracorporeal circulation under local anesthesia. After commencing extracorporeal circulation the patient was anesthetized and intubated. During this whole time period no relevant drop in mean arterial pressure was observed. The patient underwent routine replacement of the ascending aorta and was extubated the day after surgery without any neurologic sequelae. Awake cannulation and inception of extracorporeal circulation can prevent the hemodynamic deterioration and cardiac arrest often seen during induction of anesthesia in patients with cardiac tamponade.