Severe complications from placement of cerebrospinal fluid drains (CSFD) during first-stage thoracic endovascular aortic repair (TEVAR) and fenestrated-branched endovascular repair (F-BEVAR) of pararenal and thoracoabdominal aortic aneurysms (TAAAs) were found to occur at an “alarming rate” in a prospective, nonrandomized study published by the Journal of Vascular Surgery—so much so the investigators behind the research changed their practice.
Conducted by a team led by Gustavo S. Oderich, MD, and Jussi M. Kärkkäinen, MD, the researchers established that the risk of major CSFD-related complications “is not negligible and should be carefully weighed against its potential benefits,” despite the procedure being widely used to prevent ischemic spinal cord injury during complex aortic repair.
“One-third of spinal cord injuries were caused by CSFD placement,” wrote Kärkkäinen, at the time of the study a visiting research fellow at the Mayo Clinic in Rochester, Minnesota, et al. The most worrisome finding was the rate of spinal hematoma, but intracranial hemorrhage also occurred. “The use of fluoroscopic guidance may decrease the risk of CSFD-related complications.”
The research team had set out to determine the rates and risk factors of complications related to CSFD during the two endovascular procedures.
The study cohort included patients with pararenal and TAAAs enrolled between November 2013 and October 2018. “The presence of substantial degenerative lumbar disease [DLD], thought to make drain placement difficult (such as spinal canal stenosis), was identified based on review of preoperative computed tomography [CT] scan or CT angiography radiology reports or history of lowerback surgery,” the authors noted.
Of the 293 consecutive patients enrolled in the trial, 106 were treated without CSFD and excluded, which included three patients who underwent staged repair and 103 patients who had single-stage F-BEVAR. Included in the study were 187 patients treated for 20 pararenal and 167 TAAAs. With a mean age of 73, 70% of them male, they received CSFD in 240 procedures, including 51 first-stage TEVARs, 184 index F-BEVARs, and five completion temporary aneurysm sac perfusion (TASP) procedures.
The results showed that 19 patients (10%) had 22 CSFDrelated complications after 21 aortic procedures (9%). Complications were graded as severe to moderate in 17 patients (9%), the investigators found. There were 12 patients (6%) with intracranial hypotension, including three (2%) who had intracranial hemorrhage, and nine (5%) with post-dural puncture headache, which required blood patches in six. Another six patients (3%) developed spinal hematomas resulting in paraplegia in two (1%) and transient paraparesis in two (1%). One patient had CSF leakage from the puncture site with no intervention required.
“Four patients had bleeding during attempted drain placement, which required postponement of F-BEVAR,” the researchers continued. “Technical difficulties were experienced in 57 drain insertions (24%), more often in patients with DLD than in those without DLD (35/113 [31%] vs. 22/121 [18%]; p=0.03). Fluoroscopic guidance was used in 44 drain placements (18%) with a lower rate of technical difficulties compared with the blind approach (9% vs. 28%; p=0.01).
“There was a statistically nonsignificant trend toward more complications in patients with technical challenges (14% vs. 7%; p=0.10).”
Of 13 study patients who developed spinal cord injuries during aortic procedures, four (31%) were attributed to CSFD, the authors added.
Noting the study’s 9% rate of CSFD-related complications during endovascular procedures for pararenal and TAAAs, the authors reported their findings “nearly identical to the 10% rate” found in a systematic review by Lisa Q. Rong, MD, et al, of Weill Cornell Medical College, New York, published in the British Journal of Anaesthesia. “The complication risk was similar in first-stage TEVAR and F-BEVAR procedures,” they explained. “An alarming 4% of the study patients had severe, potentially life-threatening spinal drain complications, which possibly contributed to the death of two patients (1%). In comparison, the rates of severe complications and death in the previous systematic review were essentially the same, at 2.7% and 0.3%, respectively. The incidence of ICH [intracranial hemorrhage] in our series was also comparable, but the incidence of spinal hematomas (3.0%) was higher in our study compared with the systematic review (0.8%).”
Explaining the rationale behind the change in their practice, the authors continued: “Because of the high rate of spinal hematomas, we no longer recommend CSFD during first-stage TEVARs or for patients with pararenal or extent IV TAAAs who require shorter segments of supraceliac coverage. In addition, CSFD is individualized for patients with extent III TAAAs and used routinely for extent I and II TAAAs. Among patients who undergo F-BEVAR without a drain, CSFD is indicated only if the patient develops irreversible changes in intraoperative neuromonitoring or postoperative neurologic symptoms of SCI.”
In terms of the study’s shortcomings, the investigators pointed to what they described as its most major limitation: the retrospective nature of collecting CSFD-related data.
“Although the note template for spinal drain insertion procedure was fairly well-structured in our electronic medical record, there is a possibility of variation in reporting between neuroradiologist and anesthesiologist because these specialists used different note templates,” they wrote.
“The association between CSFD and ICH is often obscure, and causality can be difficult to establish; the authors agreed on the etiology of two ICHs and one remained inconclusive.”
CT scans, the researchers went on, are often reported in a standardized fashion by the radiologists but “DLD was not well-defined in this retrospective study because it mostly relied on the radiology report, and it is very common in middle aged to older individuals.”
“This is the first study to analyze CSFD-related complications in first-stage TEVAR and F-BEVAR of pararenal and TAAAs in a comprehensive and systematic way,” the authors wrote in conclusion. “It demonstrated an alarming rate of severe complications which has led to changes in practice in our hospital. Although CSFD is widely used to prevent ischemic SCI [spinal cord injury] during complex aortic repair, the risk of major CSFD-related complications is not negligible and should be carefully weighed against its potential benefits. Use of fluoroscopic guidance may reduce the risk of CSFD complications.”
Of the organizations noted by the authors as conflicts of interest, none had any involvement in the research, they reported.