Spinal cord injury (SCI) remains one of the most feared complications of open aortic repair, often leading to severe morbidity and, in some cases, death. Prevention continues to represent a substantial challenge, with reported incidence ranging between 6% and 40%. Owing to its clinical impact, the pathophysiology underlying SCI has been extensively studied.

Likewise, numerous preventive strategies have been documented in the literature. Despite this, no consensus has been reached regarding the optimal approach for minimizing SCI risk. Spinal CSF drainage—although widely adopted—remains a debated modality, and its actual protective value continues to be questioned.

In this context, Amabile et al. conducted a comprehensive analysis using data from the Society of Thoracic Surgeons Adult Cardiac Surgery Database (STS-ACSD), evaluating the effectiveness of preoperative CSF drainage in preventing spinal complications while accounting for patient-specific and perioperative factors. The study included adults older than 18 years undergoing open DTAA or TAAA repair, classified by Crawford extent. Exclusion criteria were prior neurologic deficits, concomitant aortic root surgery, traumatic aortic disease, endovascular exclusion, postoperative drain placement, and intraoperative mortality. The primary endpoints were lower-extremity paralysis lasting >24 hours and a composite of paralysis/paresis lasting >24 hours. Perioperative mortality (30 days) served as a secondary outcome.

The statistically significant observations revealed a higher use of neuroprotective measures in TAAA compared with DTAA. Patients who received CSF drainage were also more likely to present with additional risk factors such as chronic aortic dissection, prior aortic surgery, chronic lung disease, and hypertension. They also required more frequent intraoperative transfusions, thoracoabdominal incisions, and adjunctive neuroprotective strategies.

According to the key findings from multivariable logistic regression, TAAA patients exhibited a higher incidence of SCI, while perioperative mortality remained similar between DTAA and TAAA, and approximately tripled in the presence of SCI. Importantly, a significant and independent association (p < .001) emerged between CSF drain placement and increased risk of paralysis/paresis in TAAA—but not DTAA. Additional predictors of SCI in TAAA included advanced age, prior myocardial infarction, prolonged cardiopulmonary bypass duration, urgent surgical status, and Crawford type II/III extent. Notably, no other neuroprotective adjunct demonstrated a significant association with SCI reduction.

Integrating these findings, the authors hypothesize that the positive association between CSF drainage and SCI likely reflects selection bias, with drains being used more frequently in inherently high-risk patients. Despite the ambiguity in causal interpretation, the study underscores the high rate of CSF drain use, suggesting appropriate identification of high-risk anatomical and clinical profiles by operative teams. Nevertheless, the persistently high SCI incidence in this subgroup raises the question: is CSF drainage a hazardous neuroprotective intervention, or simply a marker of elevated baseline risk?

COMMENTARY:

The authors successfully refocus attention on a clinically relevant and persistently debated issue. Their multicenter analysis offers enhanced external validity, increased statistical power, and reduced institutional bias. However, one of the most striking findings is the unexpected association between CSF drain placement and an increased incidence of SCI in TAAA patients—an observation that contrasts sharply with the widely accepted protective role described throughout decades of published literature. This counterintuitive result inevitably prompts deeper scrutiny of the study’s methodological framework.

Indeed, the data strongly suggest the presence of selection bias. According to the variables recorded, CSF drains were more frequently used in patients with hemodynamic instability, extensive repairs, emergent operations, or other high-risk features. In this sense, CSF drainage may reflect the surgeon’s anticipation of elevated SCI risk rather than representing a causal mechanism for neurologic injury. Seen through this lens, the association more likely identifies complex cases rather than exposing a detrimental effect of the drain itself.

Current ESVS guidelines support an individualized approach to CSF drainage, recommending its use on the basis of patient-specific SCI risk. Importantly, no high-level evidence mandates routine prophylactic drainage. Furthermore, risk prediction models for SCI remain limited, as no contemporary technology reliably assesses intraspinal collateral circulation. In descending thoracic aortic disease, CSF drainage is considered beneficial in selected high-risk scenarios, although it carries a complication rate <5%. Even so, guideline authors consistently portray CSF drainage as a therapeutic option rather than a uniform prophylactic requirement.

The present study is also limited by the absence of information regarding the exact timing and indication for drain placement—whether anticipatory or reactive. As highlighted by Sanaiha and Chen, no preoperative imaging, hemodynamic parameters, or neuromonitoring responses were collected, placing the study within a framework of low clinical granularity. Although the large sample size strengthens the analysis, the lack of detailed contextual data constrains the interpretability of its conclusions.

Taken together, the authors deserve recognition for revisiting a complex and clinically important topic that continues to influence outcomes after open aortic repair. One of the major strengths of this study lies in helping refine patient selection for CSF drainage and encouraging more nuanced risk stratification. SCI remains a devastating complication that profoundly affects long-term quality of life, increases mortality, prolongs hospitalization, and consumes substantial healthcare resources. The findings presented here hold significant clinical value by prompting re-evaluation of current practices and encouraging further discussion—particularly as endovascular therapy expands and new patterns of SCI emerge.

REFERENCE:

Amabile A, Bonnell LN, Del Vecchio A, Basciano A, Antonios J, Kaneko T, et al. Spinal Cord Protection for Open Descending Thoracic and Thoracoabdominal Aorta Surgery: Analysis of The Society of Thoracic Surgeons Adult Cardiac Surgery Database. Ann Thorac Surg. 2025 Aug;120(2):302-310. DOI: 10.1016/j.athoracsur.2025.05.002.