Use of cerebrospinal fluid drainage catheters during single-stage transmediastinal repair of ascending/descending aortic aneurysms.

URGICAL PROCEDURES of the thoracic aorta present unique perioperative challenges and carry with them significant morbidity and mortality, not only because of the presence of severe comorbid conditions, but also because of the interruption of blood flow to critical organs. Atherosclerotic thoracic aortic aneurysms, if left untreated, have a high incidence of complications. The incidence of rupture or dissection is 31% for ascending aneurysms greater than 6 cm in diameter and 43% for descending thoracic aneurysms larger than 7 cm.1 The conventional surgical approach for aneurysms affecting the ascending aorta, aortic arch, and descending thoracic aorta is the “staged elephant trunk” procedure, first described by Borst et al 2-4 in 1983. The first component of the staged procedure is the repair of the ascending aorta and aortic arch aneurysm under cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA), via a median sternotomy incision. A residual length of graft is left in the descending aorta to facilitate repair of the descending aortic aneurysm at a later stage. Because this approach involves 2 major surgical procedures, with their corresponding risks and complications, some patients are unable to have the repair completed. 5-7 Recently, Beaver and Martin, 8 from this institution, described a single-stage repair of the ascending aorta, aortic arch, and descending thoracic aorta via median sternotomy through a transmediastinal approach. The operation is performed on patients in whom the descending thoracic aortic aneurysm tapers to a normal caliber above the level of the diaphragm. It is performed under conditions of CPB; DHCA; and, as described, with retrograde cerebral perfusion. This single-stage procedure involves initially the anastomosis of a Dacron graft to the distal descending aorta through a transmediastinal transverse supradiaphragmatic aortotomy incision, followed by reimplantation of arch vessels and suturing of the proximal graft to the ascending aorta, at which point the patient is rewarmed and separated from CPB8 (Figs 1-3). Their reported perioperative mortality was 14% with a 21% incidence of neurologic injury. Of interest, 2 of 3 patients who suffered neurologic injury presented with lower-extremity paraplegia, and a third patient had reversal of the neurologic deficit after a cerebrospinal fluid (CSF) drainage catheter was placed in the postoperative period. This outcome prompted the authors to begin placing CSF drainage catheters 12 hours preoperatively because of concerns of major bleeding associated with CPB and DHCA in this population, as well as the theoretical risk of placing spinal drains postoperatively. In this report, experience with a similar patient who had successful reversal of postoperative paresis with CSF drainage placement and 2 subsequent patients who underwent singlestage surgery with preoperative placement of a CSF drainage catheter are described. A brief review and discussion of the literature concerning the use of spinal drains to protect the spinal cord during surgical procedures of the thoracic aorta follows the case reports.