Spinal Cord Injury Risk in Open Repair for Descending Thoracic and Thoracoabdominal Aneurysm

Objective: In open repair for descending thoracic aortic aneurysm (DTAA) or thoracoabdominal aortic aneurysm (TAAA), the influence of re-interventions on spinal cord injury (SCI) remains unclear. This study evaluated the relationships between re-interventions, atherosclerosis, and SCI. Methods: We retrospectively reviewed 78 patients who underwent open surgical repair for DTAA or TAAA between April 2011 and May 2023. The associations of SCI with (i) re-interventions with a history of endovascular therapy and graft replacement and (ii) atherosclerotic factors, including monocyte count, triglyceride levels (TG), and intra-aortic plaques, were examined. Results: The rates of SCI complications and 30-day mortality were both 3.8% (3/78). There was no significant difference between the incidence of SCI in the re-intervention and first-time intervention groups (p >0.90). However, patients with protruding plaque on computed tomography (CT) were more affected by SCI than those without (13.3% vs. 1.6%, p = 0.034). Univariate analysis revealed that SCI was associated with increased monocyte count, TG, protruding plaques on CT, and intraoperative blood loss. Conclusion: Re-interventions for DTAA and TAAA showed no association with the development of SCI under appropriate protective measures. The implicated risk factors may be atherosclerosis factors such as elevated monocyte count, TG, and protruding plaques on CT.

Usefulness of the H-Reflex for Intraoperative Monitoring of Thoracoabdominal Aneurysms

PURPOSE

Intraoperative neurophysiologic monitoring in thoracoabdominal aneurysms (TAAA) is essential to avoid intraoperative spinal cord injury). Motor and somatosensory evoked potentials may be considered intraoperative tools for detecting spinal cord injury. H-reflex is a well-known neurophysiologic technique to evaluate L5-S1 root. Current evidence supports the observation that H-reflex changes may occur with spinal cord damage as high as the cervical level. This study aimed to evaluate the usefulness of the H-reflex in these surgeries.

METHODS

The use of intraoperative H-reflex in TAAA monitoring was evaluated in 12 patients undergoing open or endovascular repair of TAAA for a period of four years (2016-2020) using somatosensory evoked potentials (SSEPs) and transcranial motor evoked potentials (TcMEPs) and bilateral H-reflex.

RESULTS

Six neurophysiologic alarms were recorded in five of the 12 patients. Summarizing the neurophysiologic changes of our series, we considered a peripheral change when we detected a unilateral loss of SSEPs, TcMEPs, and H-reflex. Instead, we assumed a central change when we detected a unilateral or bilateral loss of TcMEPs and H-reflex with normal SSEPs, which we considered a sign of spinal cord ischemia. Interestingly H-reflex always changed significantly in combination with TcMEPs in the same fashion.

CONCLUSIONS

According to our series, H-reflex can detect intraoperative changes with the same sensitivity as TcMEPs in TAAA surgeries. With the support of other techniques, it can be useful to localize the origin of the lesion (peripheral or central spinal cord), to help in surgical decision-making to avoid postoperative neurologic damage. Based on our results, we recommend the systematic use of H-reflex in TAAA surgeries.

Usefulness of Motor Evoked Potential Measurement and Analysis of Risk Factors for Spinal Cord Ischaemia from 300 Cases of Thoracic Endovascular Aortic Repair

OBJECTIVE

This study investigated the usefulness of motor evoked potentials (MEPs) for intra-operative monitoring to detect the risk of spinal cord ischaemia (SCI) during thoracic endovascular aortic repair (TEVAR). Risk factors for SCI in TEVAR were also analysed.

METHODS

Among 330 TEVARs performed from February 2009 to October 2018, 300 patients underwent intra-operative MEP monitoring. SCI risk groups were extracted based on MEP amplitude changes using a cutoff value of 50%. When the amplitude decreased to < 50% of the pre-operative value, intra-operative mean arterial pressure (MAP) was increased by about 20 mmHg using noradrenaline, whereas MAP was usually controlled to about 80 mmHg during surgery. Other efforts were also made to increase MEP amplitude by increasing cardiac output, correcting anaemia, and finishing the surgery promptly. Based on MEP amplitude data, SCI risk groups were extracted and risk factors for SCI in TEVAR were analysed.

RESULTS

A total of 283 non-SCI risk patients and 17 SCI risk patients by MEP monitoring were extracted; only 1.0% developed immediate paraplegia and none developed delayed paraplegia. Bivariable analysis showed significant differences in chronic kidney disease, haemodialysis, artery of Adamkiewicz closure, and stent graft (SG) covered length ≥ 8 vertebral bodies. Logistic regression analysis showed hyperlipidaemia (odds ratio [OR] 3.55, 95% confidence interval [CI] 1.08 - 11.67; p = .037), SG covered length ≥ 8 vertebral bodies (OR 1.35, 95% CI 1.02 - 1.78; p = .034), and haemodialysis (OR 27.78, 95% CI 6.02 - 128.22; p < .001) were the most influential risk factors for SCI in TEVAR.

CONCLUSION

MEPs might be a useful monitoring tool to predict SCI in TEVAR. In addition, hyperlipidaemia, SG covered length ≥ 8 vertebral bodies, and haemodialysis represent key risk factors for SCI during TEVAR.

How Would I Treat My Own Thoracoabdominal Aortic Aneurysm: Perioperative Considerations From the Anesthesiologist Perspective

A thoracoabdominal aortic aneurysm (TAAA) can be potentially life-threatening due to its associated risk of rupture. Thoracoabdominal aortic aneurysm repair, performed as endovascular repair and/or open surgery, is the recommended therapy of choice. Hemodynamic instability, severe blood loss, and spinal cord or cerebral ischemia are some potential hazards the perioperative team has to face during these procedures. Therefore, preoperative risk assessment and intraoperative anesthesia management addressing these potential hazards are essential to improving patients' outcomes. Based on a presented index case, an overview focusing on anesthetic measures to identify perioperatively and manage these risks in TAAA repair is provided.

Endovascular occlusion of segmental arteries feeding the anterior spinal artery to stage endovascular thoracoabdominal aortic repair

Objective

Minimally invasive segmental artery coil embolization was introduced to prevent spinal cord ischemia after endovascular repair of thoracoabdominal aortic aneurysms. There is no consensus on whether the endovascular occlusion of segmental arteries feeding directly the anterior radiculomedullary artery and anterior spinal artery can be safely performed without causing spinal cord ischemia. Our aim was to investigate the feasibility and clinical impact of endovascular occlusion of segmental arteries supplying the anterior spinal artery during minimally invasive segmental artery coil embolization in patients with thoracoabdominal aortic aneurysms.

Methods

Between January 2018 and July 2020, 54 patients (36 male; mean age, 71.1 ± 9.3 years) underwent direct embolization of segmental arteries feeding the anterior radiculomedullary artery before endovascular repair of thoracoabdominal aortic aneurysms. End points included technical success of minimally invasive segmental artery coil embolization of segmental arteries, anterior radiculomedullary artery, neurological complications, and in-hospital mortality after minimally invasive segmental artery coil embolization and endovascular repair of thoracoabdominal aortic aneurysms.

Results

The thoracoabdominal aortic aneurysm classification was type I (n = 8), type II (n = 24), type III (n = 11), and type IV (n = 11). During minimally invasive segmental artery coil embolization, 388 segmental arteries were occluded, each patient having 7.2 ± 3.1 coiled segmental arteries occluding 64.5% (25-100%) of open segmental arteries within the treated aortic segment. Altogether, 66 anterior radiculomedullary arteries were seen originating between Th8 and L3 levels from 85 (21.9%) segmental arteries. In 10 patients (18.5%), 2 large anterior radiculomedullary arteries were identified, and 1 patient (1.9%) showed 3 anterior radiculomedullary arteries on the spinal arteriography. No spinal cord ischemia or procedure-related complications occurred after minimally invasive segmental artery coil embolization. After 47.9 ± 39.4 days, all patients received endovascular repair of their thoracoabdominal aortic aneurysms. There was no in-hospital mortality. One male patient developed incomplete temporary spinal cord ischemia after endovascular repair.

Conclusions

Minimally invasive segmental artery coil embolization of segmental arteries feeding the anterior spinal artery in patients with thoracoabdominal aortic aneurysms to prevent spinal cord ischemia after endovascular repair is feasible and clinically safe.

A slow-releasing donor of hydrogen sulfide inhibits neuronal cell death via anti-PANoptosis in rats with spinal cord ischemia‒reperfusion injury

BACKGROUND

Spinal cord ischemia‒reperfusion injury (SCIRI) can lead to paraplegia, which leads to permanent motor function loss. It is a disastrous complication of surgery and causes tremendous socioeconomic burden. However, effective treatments for SCIRI are still lacking. PANoptosis consists of three kinds of programmed cell death, pyroptosis, apoptosis, and necroptosis, and may contribute to ischemia‒reperfusion-induced neuron death. Previous studies have demonstrated that hydrogen sulfide (H2S) exerts a neuroprotective effect in many neurodegenerative diseases. However, whether H2S is anti-PANoptosis and neuroprotective in the progression of acute SCIRI remains unclear. Thus, in this study we aimed to explore the role of H2S in SCIRI and its underlying mechanisms.

METHODS

Measurements of lower limb function, neuronal activity, microglia/macrophage function histopathological examinations, and biochemical levels were performed to examine the efficacy of H2S and to further demonstrate the mechanism and treatment of SCIRI.

RESULTS

The results showed that GYY4137 (a slow-releasing H2S donor) treatment attenuated the loss of Nissl bodies after SCIRI and improved the BBB score. Additionally, the number of TUNEL-positive and cleaved caspase-3-positive cells was decreased, and the upregulation of expression of cleaved caspase-8, cleaved caspase-3, Bax, and Bad and downregulation of Bcl-2 expression were reversed after GYY4137 administration. Meanwhile, both the expression and activation of p-MLKL, p-RIP1, and p-RIP3, along with the number of PI-positive and RIP3-positive neurons, were decreased in GYY4137-treated rats. Furthermore, GYY4137 administration reduced the expression of NLRP3, cleaved caspase-1 and cleaved GSDMD, decreased the colocalization NeuN/NLRP3 and Iba1/interleukin-1β-expressing cells, and inhibited proinflammatory factors and microglia/macrophage polarization.

CONCLUSIONS

H2S ameliorated spinal cord neuron loss, prevented motor dysfunction after SCIRI, and exerted a neuroprotective effect via the inhibition of PANoptosis and overactivated microglia-mediated neuroinflammation in SCIRI.

Complex abdominal aortic aneurysms: a review of radiological and clinical assessment, endovascular interventions, and current evidence of management outcomes

Endovascular aortic aneurysm repair (EVAR) is an established approach to treating abdominal aortic aneurysms, however, challenges arise when the aneurysm involves visceral branches with insufficient normal segment of the aorta to provide aneurysm seal without excluding those vessels. To overcome this, a range of technological developments and solutions have been proposed including fenestrated, branched, physician-modified stents, and chimney techniques. Understanding the currently available evidence for each option is essential to select the most suitable procedure for each patient. Overall, the evidence for fenestrated endovascular repair is the most comprehensive of these techniques and shows an early post-operative advantage over open surgical repair (OSR) but with a catch-up mortality in the mid-term period. In this review, we will describe these endovascular options, pre- and post-procedure radiological assessment and current evidence of outcomes.

Melatonin Exerts an Anti-Panoptoic Role in Spinal Cord Ischemia-Reperfusion Injured Rats

Paraplegia is a serious consequence of spinal cord ischemia-reperfusion (SCIR) injury, which leads to neuron death and permanent loss of motor function. However, there is no effective treatment for SCIR. Melatonin exerts a neuroprotective effect in neurodegenerative diseases. However, whether pyroptosis, apoptosis, and necroptosis (PANoptosis) is the primary cause of the massive neural death in SCIR is unknown, and if melatonin exhibits anti-PANoptotic effect in rescuing the disastrous damage is to be decided. This study indicates that melatonin confers neuroprotection in SCIR, attenuating the loss of Nissl body and improving Basso, Beattie & Bresnahan locomotor rating scale scores. Specifically, the apoptotic hallmarks in neurons are increased in SCIR injured spinal cord compared to the sham group. The upregulated trend is reversed by melatonin while the effect of melatonin is abolished by the administration of luzindole, a selective melatonin receptor antagonist. Moreover, similar patterns are found in the necroptotic markers in neurons, the pyroptotic indicators, and the interleukin-1β staining in microglia. In conclusion, PANoptosis may underlie the mass neural death and paraplegia in SCIR, and melatonin confers neuroprotection to the spinal cord via inhibiting PANoptosis.

Risk Factors for Spinal Cord Injury during Endovascular Repair of Thoracoabdominal Aneurysm: Review of the Literature and Proposal of a Prognostic Score

Despite recent improvements, spinal cord ischemia remains the most feared and dramatic complication following extensive aortic repair. Although endovascular procedures are associated with a lower risk compared with open procedures, this risk is still significant and must be considered. A combined medical and surgical approach may help to optimize the tolerance of the spinal cord to ischemia. The aim of this review is to describe the underlying mechanism involved in spinal cord injury during extensive endovascular aortic repair, to describe the different techniques used to improve spinal cord tolerance to ischemia-including the prophylactic or curative use of spinal drainage-and to propose our algorithm for spinal cord protection and the rational use of spinal drainage.

Spinal cord protection in open and endovascular approaches to thoracoabdominal aortic aneurysms

Despite advancements in surgical and postoperative management, spinal cord injury has been a persistent complication of both open and endovascular repair of thoracoabdominal and descending thoracic aortic aneurysm. Spinal cord injury can be explained with an ischemia-infarction model which results in local edema of the spinal cord, damaging its structure and leading to reversible or irreversible loss of its function. Perfusion of the spinal cord during aortic procedures can be enhanced by several adjuncts which have been described with a broad variety of evidence in their support. These adjuncts include systemic hypothermia, cerebrospinal fluid drainage, extracorporeal circulation and distal aortic perfusion, segmental arteries reimplantation, left subclavian artery revascularization, and staged aortic repair. The Authors here reviewed and discussed the role of such adjuncts in preventing spinal cord injury from occurring, pinpointing current evidence and outlining future perspectives.

Hybrid Treatment of Complex Diseases of the Aortic Arch and Descending Thoracic Aorta by Frozen Elephant Trunk Technique

The surgical management of acute and chronic complex diseases involving the aortic arch and the descending thoracic aorta remains challenging. Hybrid procedures associating total open arch replacement and stent-grafting of the proximal descending aorta were developed to allow a potential single-stage treatment, promote remodeling of the downstream aorta, and facilitate a potential second-stage thoracic endovascular aortic repair by providing an ideal landing zone. While these approaches initially used various homemade combinations of available conventional prostheses and stent-grafts, the so-called frozen elephant trunk technique emerged with the development of several custom-made hybrid prostheses. The aim of this study was to review the contemporary outcomes of this technique in the management of complex aortic diseases, with a special focus on procedural planning, organ protection and monitoring, refinements in surgical techniques, and long-term follow-up.

Early surgical intervention for acute spinal cord injury: time is spine

Acute traumatic spinal cord injury (tSCI) is a devastating occurrence that significantly contributes to global morbidity and mortality. Surgical decompression with stabilization is the most effective way to minimize the damaging sequelae that follow acute tSCI. In recent years, strong evidence has emerged that supports the rationale that early surgical intervention, within 24 h following the initial injury, is associated with a better prognosis and functional outcomes. In this review, we have summarized the evidence and elaborated on the nuances of this concept. Additionally, we have reviewed further concepts that stem from "time is spine," including earlier cutoffs less than 24 h and the challenging entity of central cord syndrome, as well as the emerging concept of adequate surgical decompression. Lastly, we identify barriers to early surgical care for acute tSCI, a key aspect of spine care that needs to be globally addressed via research and policy on an urgent basis.

Safety and Efficacy of Inner Branched Stent-Graft in the Treatment of Aortic Arch Disease: A Systematic Review

OBJECTIVE

To provide a descriptive overview on the contemporary outcomes of thoracic endovascular arch repair with inner branched endoprosthesis (bTEVAR) for the treatment of aortic arch pathologies.

METHODS

A comprehensive literature search was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Pre-defined search terms were used to interrogate PubMed and OVID Medline databases from January 1999 to July 2022. Patient characteristics, indication for treatment, procedural data, mortality rates, postoperative complications, and reintervention rate during follow-up were evaluated.

RESULTS

Nineteen articles were included, encompassing a total of 618 patients who received bTEVAR, most of which were double-branched (63.9%, n=395). The main indication for treatment was aneurysm secondary to chronic aortic dissection (38.8%, n=240/618) with a mean maximum diameter of 58.3±11.4 mm. Pooled mean technical success rate was 97.4±4.4% (95% confidence interval [CI]=95.1%-99.5%); 2 and 3 patients required conversion to chimney technique and open repair, respectively. Among the pooled rates of early complications, postoperative stroke was the highest (10.5%; 95% CI=6.8%-14.3%). Thirty-day and in-hospital mortality rate was 5.5% (95% CI=2.6%-9.7%). Forty patients (6.5%; 95% CI=2.5%-9.5%) required early reintervention. During a mean follow-up of 20.7±13.5 months, the mortality rate was 18.2% (n=108/593; 95% CI=8.6%-20.6%) where 12 (11.1%) were aortic-related. Pooled late reintervention rate was 9.6% (95% CI=4.8%-14.3%). Comparison of demographics and outcomes found no significant difference between single and double bTEVAR.

CONCLUSION

Branched thoracic endovascular aortic repair is a promising approach for aortic arch pathologies with a high technical success rate despite a steep learning curve. However, contemporary outcomes reflect that postoperative stroke remains the predominant concern. Further experience and long-term follow-up are required to sufficiently elucidate the safety and durability of bTEVAR in the management of aortic pathologies for high-risk patients.

CLINICAL IMPACT

This systematic review summarized the contemporary outcomes of thoracic endovascular aortic repair with different inner branched stent-grafts for the management of aortic arch pathologies. Pooled results from nineteen studies with 618 patients demonstrated a high technical success rate and an acceptable mortality rate. However, postoperative stroke remains the major concern. Long-term follow-up is needed to evaluate its durability.

Anesthesia management of patients undergoing thoracic endovascular aortic repair: A retrospective analysis of single center

Thoracic endovascular aortic repair (TEVAR) is a new alternative surgical treatment for aortic pathologies, which is more minimally invasive. The aim of current study was to summarize the single-center experience of general anesthesia for patients undergoing TEVAR. In adult patients undergoing surgery for congenital heart disease, the strategy of "fast-track" anesthesia with early extubation in theater is associated with a shorter intensive care unit (ICU) stay, and lower health-care-related costs. Fast-track anesthesia has not been assessed in patients under TEVAR. Adult patients who received general anesthesia for TEVAR in our center from January 2020 to December 2020 were included. Baseline characteristics, airway management, anesthetic techniques and major complications were collected. A total of 204 (171 male, mean age 58.1 ± 11.5 years) patients met inclusion criteria for this study. The distribution of pathologies included 29 descending thoracic aneurysms, 87 type B dissections, and 88 intramural hematoma/perforating aortic ulcer. Etomidate was the induction agent in 190 (93.1%) patients, compared with propofol in 16 (7.8%). Cisatracurium was the muscle relaxant in 201 (98.5%), compared with rocuronium in 3 (1.5%). Midazolam (benzodiazepines) was given to 124 (60.8%) patients during anesthesia induction. General anesthesia was maintained with sevoflurane in 85.3% (174) patients, dexmedetomidine in 201 (98.5%) and propofol in 204 (100%). Postoperative length of stay (LOS) in the hospital was 6.0 (5.0-7.8) days. LOS in the ICU was 23.0 (20.0-27.8) hours. Overall neurologic event rate was 2.0% (n = 4) (spinal cord ischemia 1.5% [n = 3]; stroke 0.5% [n = 1]). After matching, patients who received "fast-track" anesthesia had a shorter LOS in ICUs (21.0 [18.0-24.0] vs 24.0 [20.0-44.0] hours; P = .005), and a shorter postoperative LOS in hospital (5.0 [4.0-7.0] vs 6.0 [5.0-8.0] days; P = .001). There were no in-hospital deaths. Fast-track anesthesia is feasible and safe in patients underwent TEVAR. This management strategy is associated with shorter LOS of ICU and total postoperative hospital stays. An early extubation strategy should be implemented for hemodynamically stable patients.

Biomarkers of Spinal Cord Injury in Patients Undergoing Complex Endovascular Aortic Repair Procedures-A Narrative Review of Current Literature

Complex endovascular aortic repair (coEVAR) of thoracoabdominal aortic aneurysms (TAAA) has greatly evolved in the past decades. Despite substantial improvements of postoperative care, spinal cord injury (SCI) remains the most devastating complication of coEVAR being associated with impaired patient outcome and having an impact on long-term survival. The rising number of challenges of coEVAR, essentially associated with an extensive coverage of critical blood vessels supplying the spinal cord, resulted in the implementation of dedicated SCI prevention protocols. In addition to maintenance of adequate spinal cord perfusion pressure (SCPP), early detection of SCI plays an integral role in intra- and postoperative patient care. However, this is challenging due to difficulties with clinical neurological examinations during patient sedation in the postoperative setting. There is a rising amount of evidence, suggesting that subclinical forms of SCI might be accompanied by an elevation of biochemical markers, specific to neuronal tissue damage. Addressing this hypothesis, several studies have attempted to assess the potential of selected biomarkers with regard to early SCI diagnosis. In this review, we discuss biomarkers measured in patients undergoing coEVAR. Once validated in future prospective clinical studies, biomarkers of neuronal tissue damage may potentially add to the armamentarium of modalities for early SCI diagnosis and risk stratification.

Risk Factors Associated with Spinal Cord Ischemia During Aortic Aneurysm Repair

BACKGROUND

The risk of spinal cord ischemia (SCI) with aortic aneurysm repair can cause significant neurological morbidity. Prevention of SCI is critical. We sought to identify risk factors that predispose to SCI that may guide strategies to mitigate the occurrence of SCI during and following these procedures.

METHODS

This study includes all adults who underwent atraumatic, unruptured, thoracic, and suprarenal aortic aneurysm repairs (endovascular or open) at our institution over 11 years (2010-2020). Our database included patient demographics, aneurysm anatomic features, and operative characteristics and an extreme gradient boost (XGB) machine method was used to develop a predictive model for SCI. The model was trained on an 80% randomly stratified cohort of the data and tested on the remaining 20% testing cohort. Shapley values were used to determine the most important predictive factors of SCI and decision trees were used to identify risk factor threshold values and highest risk factor combinations.

RESULTS

Information was collected for 174 adult patients undergoing thoracic and suprarenal aortic repair from 2010 to 2020. Fifty eight percent of the patients were male. Ninety seven (55.7%) patients had open aortic repair and 87 (44.3%) had endovascular repair. Twenty seven (15%) of all patients had major complications and were considered to have SCI. The XGB model converged over the training cohort with a testing cohort accuracy of 0.841 [Sensitivity = 75%, Specificity = 68%] and area under the curve of receiver operating characteristic of 0.774. The XGB model identified older age (> 65 years), history of neurologic disease, hyperlipidemia, diabetes, coronary artery disease, heart failure, poor renal function, < 6 months since last aortic repair, chronic anticoagulant use, preoperational anemia (Hemoglobin < 9), thrombocytopenia (platelet < 90,000), coagulopathy (prothrombin time > 15s and activated partial thromboplastin time > 40s), hypotension (mean arterial pressure < 70 mm Hg), longer operations (> 100 min), aneurysms longer than 5 cm, and anatomic location of aneurysm caudal to T-11 as risk factors for SCI in all types of aortic repair. Diabetic and heart failure patients undergoing longer operations (> 100 min) with thrombocytopenia or aneurysms longer than 5 cm were at the highest risk.

CONCLUSIONS

The XGB model accurately identified risk factors of SCI with aortic aneurysm repair that may guide patient selection, timing of surgery, and strategies to minimize the risk of SCI.

Effect of cerebrospinal fluid drainage pressure in descending and thoracoabdominal aortic repair: a prospective multicenter observational study

PURPOSE

Cerebrospinal fluid drainage (CSFD) is recommended during open or endovascular thoracic aortic repair. However, the incidence of CSFD complications is still high. Recently, CSF pressure has been kept high to avoid complications, but the efficacy of CSFD at higher pressures has not been confirmed. We hypothesize that CSFD at higher pressures is effective for preventing motor deficits.

METHODS

This prospective observational study included 14 hospitals that are members of the Japanese Society of Cardiovascular Anesthesiologists. Patients who underwent thoracic and thoracoabdominal aortic repair were divided into four groups: Group 1, CSF pressure around 10 mmHg; Group 2, CSF pressure around 15 mmHg; Group 3, CSFD initiated when motor evoked potential amplitudes decreased; and Group 4, no CSFD. We assessed the association between the CSFD group and motor deficits using mixed-effects logistic regression with a random intercept for the institution.

RESULTS

Of 1072 patients in the study, 84 patients (open surgery, 51; thoracic endovascular aortic repair, 33) had motor deficits at discharge. Groups 1 and 2 were not associated with motor deficits (Group 1, odds ratio (OR): 1.53, 95% confidence interval (95% CI): 0.71-3.29, p = 0.276; Group 2, OR: 1.73, 95% CI: 0.62-4.82) when compared with Group 4. Group 3 was significantly more prone to motor deficits than Group 4 (OR: 2.56, 95% CI: 1.27-5.17, p = 0.009).

CONCLUSION

CSFD is not associated with motor deficits in thoracic and thoracoabdominal aortic repair with CSF pressure around 10 or 15 mmHg.

Spinal drain for aortic aneurysm repairs: tool or toy?

PURPOSE OF REVIEW

Spinal cord injury (SCI) is one of the biggest complications in open and endovascular aortic repairs. Historically, cerebrospinal fluid drains (CSFD) have been one of the most effective modalities in reducing SCI and one of the most studied. CSFD placement also carries its' own set of procedural risks. This editorial intends to evaluate recent literature to determine whether CSFDs remain a valuable tool in aortic repair.

RECENT FINDINGS

As the surgical management of thoracic aortic aneurysms has evolved, there has been an increasing number of endovascular repairs. Current recommendations emphasize prophylactic CSFD placement in endovascular repair cases deemed 'high risk.' However, several meta-analyses differ on whether prophylactic CSFD placement reduced the risk of SCI. The incidence of SCI decreased between 2014 and 2018, despite a similar rate of prophylactic CSFD placement suggesting other techniques are being performed and may be effective in spinal cord protection as well.

SUMMARY

There has been conflicting data on whether CSFDs have a role in reducing the risk of SCI in endovascular aortic repair. Some studies suggest that there is no benefit to placement while others suggest that routine prophylactic drains should be placed for all endovascular cases. Despite this, efforts have been made to selectively place CSFDs in those patients deemed at 'high risk' for SCI. CSFDs also remain a part of rescue treatment for postoperative SCI. This suggests that CSFDs continue to be a valuable tool that we need to better comprehend. Future research is necessary to better understand how patient risk factors can be balanced with perioperative management to help identify patients who may benefit from CSFD placement.

Comparison of single- and multistage strategies during fenestrated-branched endovascular aortic repair of thoracoabdominal aortic aneurysms

OBJECTIVE

The aim of this study was to compare outcomes of single or multistage approach during fenestrated-branched endovascular aortic repair (FB-EVAR) of extensive thoracoabdominal aortic aneurysms (TAAAs).

METHODS

We reviewed the clinical data of consecutive patients treated by FB-EVAR for extent I to III TAAAs in 24 centers (2006-2021). All patients received a single brand manufactured patient-specific or off-the-shelf fenestrated-branched stent grafts. Staging strategies included proximal thoracic aortic repair, minimally invasive segmental artery coil embolization, temporary aneurysm sac perfusion and combinations of these techniques. Endpoints were analyzed for elective repair in patients who had a single- or multistage approach before and after propensity score adjustment for baseline differences, including the composite 30-day/in-hospital mortality and/or permanent paraplegia, major adverse event, patient survival, and freedom from aortic-related mortality.

RESULTS

A total of 1947 patients (65% male; mean age, 71 ± 8 years) underwent FB-EVAR of 155 extent I (10%), 729 extent II (46%), and 713 extent III TAAAs (44%). A single-stage approach was used in 939 patients (48%) and a multistage approach in 1008 patients (52%). A multistage approach was more frequently used in patients undergoing elective compared with non-elective repair (55% vs 35%; P < .001). Staging strategies were proximal thoracic aortic repair in 743 patients (74%), temporary aneurysm sac perfusion in 128 (13%), minimally invasive segmental artery coil embolization in 10 (1%), and combinations in 127 (12%). Among patients undergoing elective repair (n = 1597), the composite endpoint of 30-day/in-hospital mortality and/or permanent paraplegia rate occurred in 14% of single-stage and 6% of multistage approach patients (P < .001). After adjustment with a propensity score, multistage approach was associated with lower rates of 30-day/in-hospital mortality and/or permanent paraplegia (odds ratio, 0.466; 95% confidence interval, 0.271-0.801; P = .006) and higher patient survival at 1 year (86.9±1.3% vs 79.6±1.7%) and 3 years (72.7±2.1% vs 64.2±2.3%; adjusted hazard ratio, 0.714; 95% confidence interval, 0.528-0.966; P = .029), compared with a single stage approach.

CONCLUSION

Staging elective FB-EVAR of extent I to III TAAAs was associated with decreased risk of mortality and/or permanent paraplegia at 30 days or within hospital stay, and with higher patient survival at 1 and 3 years.

Intermediate outcomes following arch reconstruction with frozen elephant trunk, a single centre study

BACKGROUND

Surgery on the aortic arch and proximal descending thoracic aorta can be lifesaving but is also associated with significant morbidity, ranging from minor infections to severe neurological impairments as well as a substantial risk of mortality. The aim of this study is to clinically assess outcomes, with special regards to neurologic injury, as well as to seek to identify predictors of in-hospital mortality in two patient groups with different underlying aortic pathology, aneurysms and dissections, undergoing arch/descending aortic repair.

METHODS

34 patients (17 aneurysms, 17 dissections) underwent surgery involving the arch and/or descending aorta, using the Thoraflex or E-Vita frozen elephant trunk graft. 40% were female. Subgroup analysis of aneurysms compared to dissections were performed. Mean follow-up time was 53.9 months and mean age 63.5 years.

RESULTS

In-hospital mortality was 18%. Survival was comparable between aneurysms and dissections. Incidence of spinal cord injury was 9% and stroke 9%. 67% suffered any form of neurological affection, when also cognitive afflictions were included. Perioperative reoperation rate was 29% (bleeding 21%, visceral ischemia 6%, infection 2%), the need for postoperative dialysis was 11% and a series of other minor complications such as atrial fibrillation and pleurocentesis were common.

CONCLUSION

Postoperative dialysis was found to be a predictor of in-hospital mortality, while both dialysis as well as reoperation due to bleeding and/or visceral ischemia increased the risk for overall mortality, irrespective of preoperative diagnosis. Previous or current smoking appeared to be associated with negative outcomes regarding both in-hospital and overall mortality during follow-up. Trial registration Retrospectively enrolled.

Monitoring During Vascular Surgery

Vascular surgical patients present unique challenges for anesthesiologists, because of their medical vulnerabilities as well as their tendency for rapid intraoperative hemodynamic changes. Intraoperative monitors have been used for decades to reduce adverse outcomes, improve mortality, and create optimal surgical conditions. Understanding the indications and appropriate management of monitoring modalities is essential for optimizing patient care, and preventing harm associated with misinterpretation. We aim to review monitoring technologies used in complex vascular procedures, as well as the current guidelines, clinical trial outcomes, and basic mechanisms of each monitoring modality.

Significance of spinal cord perfusion pressure following spinal cord injury: A systematic scoping review

This scoping review systematically reviewed relevant research to summarize the literature addressing the significance of monitoring spinal cord perfusion pressure (SCPP) in acute traumatic spinal cord injury (SCI). The objectives of the review were to (1) examine the nature of research in the field of SCPP monitoring in SCI, (2) summarize the key research findings in the field, and (3) identify research gaps in the existing literature and future research priorities. Primary literature searches were conducted using databases (Medline and Embase) and expanded searches were conducted by reviewing the references of eligible articles and searches of Scopus, Web of Science core collection, Google Scholar, and conference abstracts. Relevant data were extracted from the studies and synthesis of findings was guided by the identification of patterns across studies to identify key themes and research gaps within the literature. Following primary and expanded searches, a total of 883 articles were screened. Seventy-three articles met the review inclusion criteria, including 34 original research articles. Other articles were categorized as conference abstracts, literature reviews, systematic reviews, letters to the editor, perspective articles, and editorials. Key themes relevant to the research question that emerged from the review included the relationship between SCPP and neurological recovery, the safety of monitoring pressures within the intrathecal space, and methods of intervention to enhance SCPP in the setting of acute traumatic SCI. Original research that aims to enhance SCPP by targeting increases in mean arterial pressure or reducing pressure in the intrathecal space is reviewed. Further discussion regarding where pressure within the intrathecal space should be measured is provided. Finally, we highlight research gaps in the literature such as determining the feasibility of invasive monitoring at smaller centers, the need for a better understanding of cerebrospinal fluid physiology following SCI, and novel pharmacological interventions to enhance SCPP in the setting of acute traumatic SCI. Ultimately, despite a growing body of literature on the significance of SCPP monitoring following SCI, there are still a number of important knowledge gaps that will require further investigation.

Neuroprotective Effects of Dexpanthenol on Rabbit Spinal Cord Ischemia/Reperfusion Injury Model

OBJECTIVE

Dexpanthenol (DXP) reportedly protects tissues against oxidative damage in various inflammation models. This study aimed to evaluate its effects on oxidative stress, inflammation, apoptosis, and neurological recovery in an experimental rabbit spinal cord ischemia/reperfusion injury (SCIRI) model.

METHODS

Rabbits were randomized into 5 groups of 8 animals each: group 1 (control), group 2 (ischemia), group 3 (vehicle), group 4 (methylprednisolone, 30 mg/kg), and group 5 (DXP, 500 mg/kg). The control group underwent laparotomy only, whereas other groups were subjected to spinal cord ischemia by aortic occlusion (just caudal to the 2 renal arteries) for 20 min. After 24 h, a modified Tarlov scale was employed to record neurological examination results. Malondialdehyde and caspase-3 levels and catalase and myeloperoxidase activities were analyzed in tissue and serum samples. Xanthine oxidase activity was measured in the serum. Histopathological and ultrastructural evaluations were also performed in the spinal cord.

RESULTS

After SCIRI, serum and tissue malondialdehyde and caspase-3 levels and myeloperoxidase and serum xanthine oxidase activities were increased (P < 0.05-0.001). However, serum and tissue catalase activity decreased significantly (P < 0.001). DXP treatment was associated with lower malondialdehyde and caspase-3 levels and reduced myeloperoxidase and xanthine oxidase activities but increased catalase activity (P < 0.05-0.001). Furthermore, DXP was associated with better histopathological, ultrastructural, and neurological outcome scores.

CONCLUSIONS

This study was the first to evaluate antioxidant, anti-inflammatory, antiapoptotic, and neuroprotective effects of DXP on SCIRI. Further experimental and clinical investigations are warranted to confirm that DXP can be administered to treat SCIRI.

Prevention of Oxidative Damage in Spinal Cord Ischemia Upon Aortic Surgery: First-In-Human Results of Shock Wave Therapy Prove Safety and Feasibility

Background Spinal cord ischemia (SCI) remains a devastating complication after aortic dissection or repair. A primary hypoxic damage is followed by a secondary damage resulting in further cellular loss via apoptosis. Affected patients have a poor prognosis and limited therapeutic options. Shock wave therapy (SWT) improves functional outcome, neuronal degeneration and survival in murine spinal cord injury. In this first-in-human study we treated 5 patients with spinal cord ischemia with SWT aiming to prove safety and feasibility. Methods and Results Human neurons were subjected to ischemic injury with subsequent SWT. Reactive oxygen species and cellular apoptosis were quantified using flow cytometry. Signaling of the antioxidative transcription factor NRF2 (nuclear factor erythroid 2-related factor 2) and immune receptor Toll-like receptor 3 (TLR3) were analyzed. To assess whether SWT act via a conserved mechanism, transgenic tlr3^-/- zebrafish created via CRISPR/Cas9 were subjected to spinal cord injury. To translate our findings into a clinical setting, 5 patients with SCI underwent SWT. Baseline analysis and follow-up (6 months) included assessment of American Spinal Cord Injury Association (ASIA) impairment scale, evaluation of Spinal Cord Independence Measure score and World Health Organization Quality of Life questionnaire. SWT reduced the number of reactive oxygen species positive cells and apoptosis upon ischemia via induction of the antioxidative factor nuclear factor erythroid 2-related factor 2. Inhibition or deletion of tlr3 impaired axonal growth after spinal cord lesion in zebrafish, whereas tlr3 stimulation enhanced spinal regeneration. In a first-in-human study, we treated 5 patients with SCI using SWT (mean age, 65.3 years). Four patients presented with acute aortic dissection (80%), 2 of them exhibited preoperative neurological symptoms (40%). Impairment was ASIA A in 1 patient (20%), ASIA B in 3 patients (60%), and ASIA D in 1 patient (20%) at baseline. At follow-up, 2 patients were graded as ASIA A (40%) and 3 patients as ASIA B (60%). Spinal cord independence measure score showed significant improvement. Examination of World Health Organization Quality of Life questionnaires revealed increased scores at follow-up. Conclusions SWT reduces oxidative damage upon SCI via immune receptor TLR3. The first-in-human application proved safety and feasibility in patients with SCI. SWT could therefore become a powerful regenerative treatment option for this devastating injury.

Two-stage aortic surgery for distal aortic arch and descending aorta aneurysms: A case report

RATIONALE

Although surgical treatment strategies for patients with extensive thoracic aortic disease involving the aortic arch have improved considerably, the impact of stent graft length and placement site on aortic remodeling at long-term follow-up is not fully understood, and the protection of the Adamkiewicz artery (AKA) using the frozen elephant trunk (FET) method is also unclear.

PATIENT CONCERNS

The patient was a 69-year-old man with diabetic nephropathy who became increasingly fatigued and started maintenance hemodialysis 6 months prior to admission. At 64 years, he underwent clipping of a right cerebellar artery aneurysm. In addition, a 1.8 cm aneurysm was found in the contralateral extracranial internal carotid artery. He also had an atrial septal defect and moderate aortic regurgitation and was receiving continuous positive airway pressure therapy for sleep apnoea syndrome.

DIAGNOSIS

He had aneurysms in the aortic arch (4.8 cm in diameter) and descending aorta (6 cm in diameter), which was located at T6-9. Preoperative 3-dimensional computed tomography showed that the (AKA) bifurcated at T10-11.

INTERVENTIONS

Considering the patient's several comorbidities and frailty, we planned to perform 1-stage extended aortic arch repair using the FET procedure. However, we performed 2-stage aortic surgery to prevent spinal ischemia, anticipating substantial cardiac enlargement and blood pressure instability due to dialysis treatment. Aortic valve replacement, atrial septal defect patch closure, and aortic arch surgery were performed. A 7-cm elephant trunk was inserted in the descending aorta. Postoperatively, the patient continued rehabilitation until his blood pressure stabilized during dialysis therapy. At postoperative week 4, he underwent thoracic endovascular aortic repair for a descending aortic aneurysm.

OUTCOMES

After surgery, his physical strength decreased; however, he recovered and was discharged 1 month later without any complications. One year after the second operation, he is living a healthy life.

LESSONS

Extensive aortic arch surgery using the FET procedure is effective for distal aortic arch and descending aortic aneurysms. Nevertheless, in cases in which the position of the AKA is close to the aortic aneurysm and blood pressure control is difficult, a 2-stage procedure and accurate positioning of thoracic endovascular aortic repair are both desirable.

Effects of fluids vs. vasopressors on spinal cord microperfusion in hemorrhagic shock induced ischemia/reperfusion

OBJECTIVE

Spinal cord injury induced by ischemia/reperfusion is a devastating complication of aortic repair. Despite developments for prevention and treatment of spinal cord injury, incidence is still considerably high majorly impacting patient outcome. Microcirculation is paramount for tissue perfusion and oxygen supply and often dissociated from macrohemodynamic parameters used to guide resuscitation. Effects of fluids vs. vasopressors in the setting of hemodynamic resuscitation on spinal cord microperfusion are unknown. Aim of this study was to compare the effects of vasopressor and fluid resuscitation on spinal cord microperfusion in a translational acute pig model of hemorrhagic shock induced ischemia/reperfusion injury.

METHODS

We designed this study as prospective randomized explorative large animal study. We induced hemorrhagic shock in 20 pigs as a model of global ischemia/reperfusion injury. We randomized animals to receive either fluid or vasopressor resuscitation. We measured spinal cord microperfusion using fluorescent microspheres as well as laser-Doppler probes. We monitored and analyzed macrohemodynamic parameters and cerebrospinal fluid pressure.

RESULTS

Spinal cord microperfusion decreased following hemorrhagic shock induced ischemia/reperfusion injury. Both fluids and vasopressors sufficiently restored spinal cord microperfusion. There were no important changes between groups (percentage changes compared to baseline: fluids 14.0 (0.31-27.6) vs. vasopressors 24.3 (8.12-40.4), p = .340). However, cerebrospinal fluid pressure was higher in animals receiving fluid resuscitation (percentage changes compared to baseline: fluids 27.7 (12.6-42.8) vs. vasopressors -5.56 ((-19.8)-8.72), p = .003). Microcirculatory resuscitation was in line with improvements of macrohemodynamic parameters.

CONCLUSIONS

Both, fluids and vasopressors, equally restored spinal cord microperfusion in a porcine acute model of hemorrhagic shock induced ischemia/reperfusion injury. However, significant differences in cerebrospinal fluid pressure following resuscitation were present. Future studies should evaluate these effects in perfusion disruption induced ischemia/reperfusion conditions of microcirculatory deterioration.

Minimally Invasive Segmental Artery Coil Embolization (MISACE) Prior to Endovascular Thoracoabdominal Aortic Aneurysm Repair

PURPOSE

Minimally Invasive Segmental Artery Coil Embolization (MISACE) is a novel approach to reduce paraplegia risk in Thoracoabdominal aortic aneurysm (TAAA) repair with limited data. We report our experience with MISACE as a method of spinal cord pre-conditioning to prevent spinal cord ischemia following endovascular repair of TAAA.

MATERIAL AND METHODS

A retrospective analysis of 17 patients who had an attempted MISACE prior to endovascular TAAA repair with mean follow-up of 350 days (2017-2020). Baseline patient and aneurysm characteristics along with procedural technique and outcomes were analyzed.

RESULTS

Mean age of 69 years and 76.5% were males. TAAA Crawford classification were II, n = 6 (35.3%), III, n = 4 (23.5%) and IV, n = 5 (29.4%). The mean aortic diameter was 70.6 ± 10.9 mm. Staged repair was performed on 9 patients. Technically successful embolization occurred in 14 patients (82.4%) and was unsuccessful in 3 patients. The median number of embolized arteries was 3 and 71% of the target arteries were between T9 and T12. Mean fluoroscopy time was 51.5 ± 22.5 min and mean contrast volume used was 132.8 ± 56.1 mL. Average number of catheters used was 4.6 and 3.5 wires. No complications related to the procedure. Mean interval between embolization to endovascular TAAA repair was 51.2 days (5-110 days). All patients received spinal drainage at the time of repair. Postoperatively, 2/14 of patients developed paraparesis in the MISACE successful group and 1/3 patients developed paraplegia in the unsuccessful group.

CONCLUSIONS

MISACE is a promising strategy to prevent SCI. This data demonstrates the technique is feasible and safe but anatomic challenges remain.

Comparison of two surgical approaches for acute type A aortic dissection: hybrid debranching versus total arch replacement

Background

The goal of this study was to determine the clinical outcomes of total arch replacement with frozen elephant trunk surgery and hybrid debranching surgery for acute type A aortic dissection patients.

Methods

From January 2017 to December 2019, the clinical data of acute type A aortic dissection patients were retrospectively collected and analyzed. There were 142 patients underwent total arch replacement with frozen elephant trunk surgery and 35 patients underwent hybrid debranching surgery.

Result

The age, the body mass index and the renal insufficiency of patients in the hybrid group were higher than those in the total arch replacement (TAR) group (all P < 0.01). The operation time, the cardiopulmonary bypass time and the aortic occlusion time of patients in the TAR group were significantly longer than those in the hybrid group (all P < 0.01). Patients in the debranching group had shorter ventilator-assisted breathing time, shorter postoperative hospital stay time and shorter intensive care unit (ICU) stay time. The incidence of pulmonary infection and transient neurological dysfunction were lower, and the transfusions of red blood cells and plasma during the perioperative period were smaller. The survival rates at 2 years were 91.9% and 85.9% in the TAR and hybrid groups, respectively.

Conclusion

Hybrid debranching operation is a safe and effective method for acute type A aortic dissection. Compared with TAR surgery, hybrid debranching surgery has the characteristics of less trauma, rapid recovery and lower incidence of complication.

Early and mid-term outcomes of thoracic endovascular aortic repair to treat aortic rupture in patients with aneurysms, dissections and trauma

OBJECTIVES

The aim of this study was to analyse outcomes of thoracic endovascular aortic repair to treat aortic rupture.

METHODS

Patient and outcome characteristics of all emergent endovascular treatments for thoracic aortic rupture between January 2009 and December 2019 were analysed.

RESULTS

Thoracic aortic rupture occurred in patients with aortic aneurysms (n = 42, 49%), aortic dissection (n = 13, 16%) or after trauma (n = 30, 35%). Preoperative cerebrospinal fluid drainage was placed in 9 patients (11%) and 18 patients (21%) underwent perioperative supra-aortic transposition. The proximal landing zones were: zone 1 (n = 1, 1%), zone 2 (n = 23, 27%), zone 3 (n = 52, 61%) and zone 4 (n = 9, 11%). Temporary spinal cord injury occurred in 1 patient (1%), permanent spinal cord injury in 7 patients (8%). Two patients (2%) experienced a postoperative stroke. Seventeen patients (20%) expired in-hospital. Aortic dissection (odds ratio: 16.246, p = 0.001), aneurysm (odds ratio: 9.090, P = 0.003) and preoperative shock (odds ratio: 4.646, P < 0.001) were predictive for mortality. Eighteen patients (21%) required a stent-graft-related aortic reintervention for symptomatic supra-aortic malperfusion (n = 3, 4%), endoleaks (n = 6, 7%), a second aortic rupture (n = 4, 5%), retrograde type A aortic dissection (n = 2, 2%), aortic-oesophageal fistulation (n = 2, 2%) and stent-graft kinking (n = 1, 1%).

CONCLUSIONS

Thoracic endovascular aortic repair in patients with aortic rupture has become a valuable treatment modality to stabilize patients. However, a significant risk of postoperative morbidity and mortality remains, particularly in patients with aortic dissections, aneurysms or shock. Patients require thorough follow-up ideally in an aortic clinic with a staff having the entire spectrum of cardiovascular and thoracic surgical expertise.

Preoperative and postoperative complications of cerebrospinal fluid drainage in descending thoracic and thoraco-abdominal aortic aneurysm surgery: a single-center retrospective study

PURPOSE

Cerebrospinal-fluid drainage (CSFD) has been performed to prevent paraplegia in descending thoracic or thoraco-abdominal aortic aneurysm (DTA/TAAA) surgery; however, CSFD itself has a risk of severe complications. We retrospectively investigated the incidence rates of CSFD-related preoperative and postoperative complications.

METHODS

Patients who underwent DTA/TAAA surgery with a CSFD catheter that was inserted on the day before surgery were enrolled. The incidence rates of complications from spinal puncture until DTA/TAAA surgery were investigated as preoperative CSFD complications, and the incidence rates from DTA/TAAA surgery to postoperative day 7 were investigated as CSFD-related postoperative complications.

RESULTS

Preoperative CSFD complications were analyzed in 123 cases. DTA/TAAA surgery was postponed due to bloody cerebrospinal fluid (2.5%) and due to meningitis (1.7%). The incidence rate of mild preoperative complications was 32.4%. Postoperative CSFD complications were analyzed in 108 cases. Intracranial hemorrhage occurred in 3.9% of cases in open surgery and other postoperative severe CSFD complications did not occur. The incidence rates of moderate/mild complications in open surgery were 2.6%/14.3% and those in TEVAR were 3.2%/19.4%.

CONCLUSION

Bloody cerebrospinal fluid and meningitis, which are severe complications associated with spinal puncture, occurred within 1 day after spinal puncture. The incidence rates of moderate/mild complications were high in both the preoperative and postoperative periods. These results showed that CSFD catheter insertion and management should be performed carefully with consideration given to the risks and benefits of CSFD.

Neuronal Pre- and Postconditioning via Toll-like Receptor 3 Agonist or Extracorporeal Shock Wave Therapy as New Treatment Strategies for Spinal Cord Ischemia: An In Vitro Study

Spinal cord ischemia (SCI) is a devastating and unpredictable complication of thoracoabdominal aortic repair. Postischemic Toll-like receptor 3 (TLR3) activation through either direct agonists or shock wave therapy (SWT) has been previously shown to ameliorate damage in SCI models. Whether the same applies for pre- or postconditioning remains unclear. In a model of cultured SHSY-5Y cells, preconditioning with either poly(I:C), a TLR3 agonist, or SWT was performed before induction of hypoxia, whereas postconditioning treatment was performed after termination of hypoxia. We measured cytokine expression via RT-PCR and utilized Western blot analysis for the analysis of signaling and apoptosis. TLR3 activation via poly(I:C) significantly reduced apoptotic markers in both pre- and postconditioning, the former yielding more favorable results through an additional suppression of TLR4 and its downstream signaling. On the contrary, SWT showed slightly more favorable effects in the setting of postconditioning with significantly reduced markers of apoptosis. Pre- and post-ischemic direct TLR3 activation as well as post-ischemic SWT can decrease apoptosis and proinflammatory cytokine expression significantly in vitro and might therefore pose possible new treatment strategies for ischemic spinal cord injury.

Temporary Reperfusion of the Aneurysm Sac as a Prevention of Spinal Cord Ischemia After Endovascular Treatment of Thoracoabdominal Aortic Aneurysm: Systematic Review and Meta-analysis

BACKGROUND

Spinal cord ischemia (SCI) is still a feared complication for patients suffering from thoracoabdominal aortic aneurysm (TAAA) who undergo endovascular treatment. The aims of this work are to review the available literature on different reperfusion methods of the aneurysm sac, and to analyze whether the different reperfusion methods, also in combination with other factors, are effective in reducing SCI risk and if the impact varies with the patient's age.

METHODS

PubMed/MEDLINE library was searched for studies published until November 2020 concerning TAAA, endovascular repair, and SCI preventive measures. Systematic review and meta-analysis were conducted according to Preferred Reporting Items for Systematic reviews and Meta-Analyses criteria. Primary outcome consisted of correlation between endovascular repair techniques (type A: single step; type B: staged approach with reperfusion branches; type C: staged sequential approach with positioning of the thoracic component). A logistic-weighted regression for each event (SCI, transient, and permanent) was then performed with type of treatment, age, and interaction between them as input factors. Finally, another logistic-weighted regression was performed to analyze the other relevant factors for which observations are available together with the endovascular technique.

RESULTS

Data from 53 studies with a total of 3095 patients were analyzed. Type A, type B, and type C endovascular strategies were adopted in 75%, 13%, and 12% of studied patients, respectively. Data showed that both type B and type C treatments are associated with lower risk of SCI, with a higher reduction of type C with respect to type B, although this positive trend is limited for elder patients. Moreover, a greater aortic diameter, a reduced aneurysm extent, and the absence of cerebrospinal fluid drainage positioning contribute to lower the risk of SCI. Concerning permanent SCI, both type B and type C are effective in reducing percentages for all ages, with type C treatment more beneficial for younger patients and type B for elder ones.

CONCLUSION

According to the anatomy and the endovascular repair feasibility criteria, staged endovascular treatment appears to offer relevant advantages over single-step treatment in reducing the risk of SCI, regardless of the reperfusion method adopted.

Spinal Cord Ischemia After Thoracoabdominal Aortic Aneurysms Endovascular Repair: From the Italian Multicenter Fenestrated/Branched Endovascular Aneurysm Repair Registry

PURPOSE

The aim of this study is to report an Italian multicenter experience analyzing the incidence and the risk factors associated with spinal cord ischemia (SCI) in a large cohort of thoracoabdominal aortic aneurysms (TAAAs) treated by fenestrated-branched endovascular aneurysm repair (F-/B-EVAR).

MATERIALS AND METHODS

All consecutive patients undergoing F-/B-EVAR in 4 Italian university centers between 2008 and 2019 were prospectively recorded and retrospectively analyzed. Spinal cord ischemia, 30 day/in-hospital adverse events, and mortality were assessed as early outcomes. Risk factors for SCI were determined by multivariable analysis.

RESULTS

A total of 351 patients received F-/B-EVAR for a TAAA. Twenty-eight (8.0%) patients died within 30 postoperative days or during the hospitalization. Regarding SCI, 47 patients (13.4%) developed neurological symptoms related to spinal cord impaired perfusion. Among them, 17 (4.8%) had a major permanent impairment. The multivariable analysis identified that SCI was associated with Crawford extent I to III (odds ratio [OR]: 20.90, p=0.004, 95% confidence interval [CI]=2.69-162.57), and with endovascular procedures performed for ruptured TAAA (OR: 5.74, p=0.010, 95% CI=1.53-21.57). Spinal cord ischemia was also significantly associated with a grade 3 bleeding during the visceral stage (OR: 4.34, p=0.005, 95% CI=1.55-12.16) and a grade 2 renal insufficiency at 30 days (OR: 7.45, p=0.002, 95% CI=2.12-26.18).

CONCLUSION

The present study indicates that SCI is still an open issue after extent I to III TAAA endovascular repair, while its incidence in extent IV TAAA and pararenal/juxtarenal aneurysms is rare. Thoracoabdominal aortic aneurysms extension, urgent TAAA repair for rupture, severe bleeding, and 30 day renal insufficiency have been identified as significant risk factors for SCI. In the presence of such factors, adjunctive strategies may be considered to reduce SCI rates, while in low-risk patients invasive or potentially-risky maneuvers might not be justified.

Intraoperative neurophysiologic monitoring in thoracoabdominal aortic aneurysm surgery can provide real-time feedback for strategic decision making

OBJECTIVES

Despite the introduction of several adjuncts to improve spinal perfusion, spinal cord ischemia (SCI) remains a devastating complication of thoracoabdominal aortic aneurysm (TAAA) repair. Our aim was to assess the effects on clinical outcome of interventions triggered by motor evoked potentials (MEP) alerts. Furthermore, we want to assess whether a multimodal intraoperative neurophysiologic monitoring (IONM) protocol is helpful for stratifying patients according to the risk of SCI at the end of the vascular phase of surgery.

METHODS

We prospectively studied one-hundred consecutive patients who underwent TAAA repair. We applied a multimodal IONM including MEP, somatosensory evoked potentials (SEP) and peripheral nerve monitoring techniques. Signal deteriorations were classified as reversible/irreversible according to whether they recovered or not at the end of monitoring (EOM), set at the end of the vascular phase of surgery. Significant MEP changes drove a series of corrective measures aimed to improve spinal perfusion.

RESULTS

The rate of immediate postoperative motor deficits consistent with SCI was significantly higher with irreversible MEP deteriorations compared to reversible ones. The interpretation of MEP findings at the EOM led to the development of risk categories for SCI, based on the association between MEP results and motor outcome.

CONCLUSIONS

Our data seem to justify interventions made to reverse MEP deterioration in order to improve the clinical outcome. A multimodal IONM protocol could improve MEP interpretation at the end of the vascular phase of surgery, supporting the surgeon in their decision-making, before concluding vascular maneuvers.

Successful one-stage operation for type B acute intramural hematoma with descending aortic rupture

A 76-year-old man who complained of back pain was referred to our hospital. Computed tomography revealed an intramural hematoma with a descending aortic rupture. Total arch replacement with the frozen elephant trunk technique and thoracic endovascular aortic repair was performed emergently in one stage. The patient was discharged without symptoms.