Spinal Cord Perfusion Pressure Research Articles

A Clinical Practice Guideline for the Management of Patients With Acute Spinal Cord Injury: Recommendations on Hemodynamic Management.

Clinical practice guideline development following the GRADE process. Hemodynamic management is one of the only available treatment options that likely improves neurologic outcomes in patients with acute traumatic spinal cord injury (SCI). Augmenting mean arterial pressure (MAP) aims to improve blood perfusion and oxygen delivery to the injured spinal cord in order to minimize secondary ischemic damage to neural tissue. The objective of this guideline was to update the 2013 AANS/CNS recommendations on the hemodynamic management of patients with acute traumatic SCI, acknowledging that much has been published in this area since its publication. Specifically, we sought to make recommendations on 1. The range of mean arterial pressure (MAP) to be maintained by identifying an upper and lower MAP limit; 2. The duration of such MAP augmentation; and 3. The choice of vasopressor. Additionally, we sought to make a recommendation on spinal cord perfusion pressure (SCPP) targets. A multidisciplinary guideline development group (GDG) was formed that included health care professionals from a wide range of clinical specialities, patient advocates, and individuals living with SCI. The GDG reviewed the 2013 AANS/CNS guidelines and voted on whether each recommendation should be endorsed or updated. A systematic review of the literature, following PRISMA standards and registered in PROSPERO, was conducted to inform the guideline development process and address the following key questions: (i) what are the effects of goal-directed interventions to optimize spinal cord perfusion on extent of neurological recovery and rates of adverse events at any time point of follow-up? and (ii) what are the effects of particular monitoring techniques, perfusion ranges, pharmacological agents, and durations of treatment on extent of neurological recovery and rates of adverse events at any time point of follow-up? The GDG combined the information from this systematic review with their clinical expertise in order to develop recommendations on a MAP target range (specifically an upper and lower limit to target), the optimal duration for MAP augmentation, and the use of vasopressors or inotropes. Using methods outlined by the GRADE working group, recommendations were formulated that considered the balance of benefits and harms, financial impact, acceptability, feasibility and patient preferences. The GDG suggested that MAP should be augmented to at least 75-80 mmHg as the "lower limit," but not actively augmented beyond an "upper limit" of 90-95mmHg in order to optimize spinal cord perfusion in acute traumatic SCI. The quality of the evidence around the "target MAP" was very low, and thus the strength of this recommendation is weak. For duration of hemodynamic management, the GDG "suggested" that MAP be augmented for a duration of 3-7days. Again, the quality of the evidence around the duration of MAP support was very low, and thus the strength of this recommendation is also weak. The GDG felt that a recommendation on the choice of vasopressor or the use of SCPP targets was not warranted, given the dearth of available evidence. We provide new recommendations for blood pressure management after acute SCI that acknowledge the limitations of the current evidence on the relationship between MAP and neurologic recovery. It was felt that the low quality of existing evidence and uncertainty around the relationship between MAP and neurologic recovery justified a greater range of MAP to target, and for a broader range of days post-injury than recommended in previous guidelines. While important knowledge gaps still remain regarding hemodynamic management, these recommendations represent current perspectives on the role of MAP augmentation for acute SCI.

Interventions to Optimize Spinal Cord Perfusion in Patients With Acute Traumatic Spinal Cord Injury: An Updated Systematic Review.

Systematic review update. Interventions that aim to optimize spinal cord perfusion are thought to play an important role in minimizing secondary ischemic damage and improving outcomes in patients with acute traumatic spinal cord injuries (SCIs). However, exactly how to optimize spinal cord perfusion and enhance neurologic recovery remains controversial. We performed an update of a recent systematic review (Evaniew et al, J. Neurotrauma 2020) to evaluate the effects of Mean Arterial Pressure (MAP) support or Spinal Cord Perfusion Pressure (SCPP) support on neurological recovery and rates of adverse events among patients with acute traumatic SCI. We searched PubMed/MEDLINE, EMBASE and ClinicalTrials.gov for new published reports. Two reviewers independently screened articles, extracted data, and evaluated risk of bias. We implemented the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach to rate confidence in the quality of the evidence. From 569 potentially relevant new citations since 2019, we identified 9 new studies for inclusion, which were combined with 19 studies from a prior review to give a total of 28 studies. According to low or very low quality evidence, the effect of MAP support on neurological recovery is uncertain, and increased SCPP may be associated with improved neurological recovery. Both approaches may involve risks for specific adverse events, but the importance of these adverse events to patients remains unclear. Very low quality evidence failed to yield reliable guidance about particular monitoring techniques, perfusion ranges, pharmacological agents, or durations of treatment. This update provides an evidence base to support the development of a new clinical practice guideline for the hemodynamic management of patients with acute traumatic SCI. While avoidance of hypotension and maintenance of spinal cord perfusion are important principles in the management of an acute SCI, the literature does not provide high quality evidence in support of a particular protocol. Further prospective, controlled research studies with objective validated outcome assessments are required to examine interventions to optimize spinal cord perfusion in this setting.

The 2023 AO Spine-Praxis Guidelines in Acute Spinal Cord Injury: What Have We Learned? What Are the Critical Knowledge Gaps and Barriers to Implementation?

Narrative summary of the 2023 AO Spine-Praxis clinical practice guidelines for management in acute spinal cord injury (SCI). The objective of this article is to summarize the key findings of the clinical practice guidelines for the optimal management of traumatic and intraoperative SCI (ISCI). This article will also highlight potential knowledge translation opportunities for each recommendation and discuss important knowledge gaps and areas of future research. Systematic reviews were conducted according to accepted methodological standards to evaluate the current body of evidence and inform the guideline development process. The summarized evidence was reviewed by a multidisciplinary guidelines development group that consisted of international multidisciplinary stakeholders. The Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) approach was used to rate the certainty of the evidence for each critical outcome and the "evidence to recommendation" framework was used to formulate the final recommendations. The key recommendations regarding the timing of surgical decompression, hemodynamic management, and the prevention, diagnosis, and management of ISCI are summarized. While a strong recommendation was made for early surgery, further prospective research is required to define what constitutes sufficient surgical decompression, examine the role of ultra-early surgery, and assess the impact of early surgery in different SCI phenotypes, including central cord syndrome. Furthermore, additional investigation is required to evaluate the impact of mean arterial blood pressure targets on neurological recovery and to determine the utility of spinal cord perfusion pressure measurements. Finally, there is a need to examine the role of neuroprotective agents for the treatment of ISCI and to prospectively validate the new AO Spine-Praxis care pathway for the prevention, diagnosis, and management of ISCI. To optimize the translation of these guidelines into practice, important barriers to their implementation, particularly in underserved areas, need to be explored. Ultimately, these recommendations will help to establish more personalized approaches to care for SCI patients. The recommendations from the 2023 AO Spine-Praxis guidelines not only highlight the current best practice in the management of SCI, but reveal critical knowledge gaps and barriers to implementation that will help to guide further research efforts in SCI.

Spinal cord perfusion pressure correlates with breathing function in patients with acute, cervical traumatic spinal cord injuries: an observational study

ObjectiveThis study aims to determine the relationship between spinal cord perfusion pressure (SCPP) and breathing function in patients with acute cervical traumatic spinal cord injuries.MethodsWe included 8 participants without cervical TSCI plus 13 patients with cervical traumatic spinal cord injuries, American Spinal Injury Association Impairment Scale grades A–C. In the TSCI patients, we monitored intraspinal pressure from the injury site for up to a week and computed the SCPP as mean arterial pressure minus intraspinal pressure. Breathing function was quantified by diaphragmatic electromyography using an EDI (electrical activity of the diaphragm) nasogastric tube as well as by ultrasound of the diaphragm and the intercostal muscles performed when sitting at 20°–30°.ResultsWe analysed 106 ultrasound examinations (total 1370 images/videos) and 198 EDI recordings in the patients with cervical traumatic spinal cord injuries. During quiet breathing, low SCPP (< 60 mmHg) was associated with reduced EDI-peak (measure of inspiratory effort) and EDI-min (measure of the tonic activity of the diaphragm), which increased and then plateaued at SCPP 60–100 mmHg. During quiet and deep breathing, the diaphragmatic thickening fraction (force of diaphragmatic contraction) plotted versus SCPP had an inverted-U relationship, with a peak at SCPP 80–90 mmHg. Diaphragmatic excursion (up and down movement of the diaphragm) during quiet breathing did not correlate with SCPP, but diaphragmatic excursion during deep breathing plotted versus SCPP had an inverse-U relationship with a peak at SCPP 80–90 mmHg. The thickening fraction of the intercostal muscles plotted versus SCPP also had inverted-U relationship, with normal intercostal function at SCPP 80–100 mmHg, but failure of the upper and middle intercostals to contract during inspiration (i.e. abdominal breathing) at SCPP < 80 or > 100 mmHg.ConclusionsAfter acute, cervical traumatic spinal cord injuries, breathing function depends on the SCPP. SCPP 80–90 mmHg correlates with optimum diaphragmatic and intercostal muscle function. Our findings raise the possibility that intervention to maintain SCPP in this range may accelerate ventilator liberation which may reduce stay in the neuro-intensive care unit.

Duroplasty for injured cervical spinal cord with uncontrolled swelling: protocol of the DISCUS randomized controlled trial

BackgroundCervical traumatic spinal cord injury is a devastating condition. Current management (bony decompression) may be inadequate as after acute severe TSCI, the swollen spinal cord may become compressed against the surrounding tough membrane, the dura. DISCUS will test the hypothesis that, after acute, severe traumatic cervical spinal cord injury, the addition of dural decompression to bony decompression improves muscle strength in the limbs at 6 months, compared with bony decompression alone.MethodsThis is a prospective, phase III, multicenter, randomized controlled superiority trial. We aim to recruit 222 adults with acute, severe, traumatic cervical spinal cord injury with an American Spinal Injury Association Impairment Scale grade A, B, or C who will be randomized 1:1 to undergo bony decompression alone or bony decompression with duroplasty. Patients and outcome assessors are blinded to study arm. The primary outcome is change in the motor score at 6 months vs. admission; secondary outcomes assess function (grasp, walking, urinary + anal sphincters), quality of life, complications, need for further surgery, and mortality, at 6 months and 12 months from randomization. A subgroup of at least 50 patients (25/arm) also has observational monitoring from the injury site using a pressure probe (intraspinal pressure, spinal cord perfusion pressure) and/or microdialysis catheter (cord metabolism: tissue glucose, lactate, pyruvate, lactate to pyruvate ratio, glutamate, glycerol; cord inflammation: tissue chemokines/cytokines). Patients are recruited from the UK and internationally, with UK recruitment supported by an integrated QuinteT recruitment intervention to optimize recruitment and informed consent processes. Estimated study duration is 72 months (6 months set-up, 48 months recruitment, 12 months to complete follow-up, 6 months data analysis and reporting results).DiscussionWe anticipate that the addition of duroplasty to standard of care will improve muscle strength; this has benefits for patients and carers, as well as substantial gains for health services and society including economic implications. If the addition of duroplasty to standard treatment is beneficial, it is anticipated that duroplasty will become standard of care.Trial registrationIRAS: 292031 (England, Wales, Northern Ireland) - Registration date: 24 May 2021, 296518 (Scotland), ISRCTN: 25573423 (Registration date: 2 June 2021); ClinicalTrials.gov number : NCT04936620 (Registration date: 21 June 2021); NIHR CRN 48627 (Registration date: 24 May 2021).

Cerebrospinal Fluid Drainage in Patients with Acute Spinal Cord Injury: A Multi-Center Randomized Controlled Trial

The secondary phase of spinal cord injury (SCI) is characterized by ischemic injury. Spinal cord perfusion pressure (SCPP), calculated as the difference between mean arterial pressure (MAP) and intrathecal pressure (ITP), has arisen as a therapeutic target for improving outcomes. Cerebrospinal fluid drainage (CSFD) may reduce ITP and thereby increase SCPP. Randomized controlled trial to evaluate the safety and feasibility of CSFD to improve SCPP and outcomes after acute SCI. Inclusion criteria included acute cervical SCI within 24hours of presentation. All patients received lumbar drain placement and appropriate decompressive surgery. Patients randomized to the control group received MAP elevation only. Patients in the experimental group received MAP elevation and CSFD to achieve ITP <10mmHg for 5days. ITP and MAP were recorded hourly. Adverse events were documented and patients underwent functional assessments at enrollment, 72hours, 90days, and 180days post-injury. Eleven patients were enrolled; 4 were randomized to receive CSFD. CSFD patients had a mean ITP of 5.3±2.5mmHg versus. 15±3.0mmHg in the control group. SCPP improved significantly, from 77±4.5mmHg in the control group to 101±6.3mmHg in the CSFD group (P < 0.01). Total motor scores improved by 15±8.4 and 57±24 points in the control and CSFD groups, respectively, over 180days. No adverse events were attributable to CSFD. CSFD is a safe, effective mechanism for reducing ITP and improving SCPP in the acute period post-SCI. The favorable safety profile and preliminary efficacy should help drive recruitment in future studies.

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.

Interventions to Optimize Spinal Cord Perfusion in Patients with Acute Traumatic Spinal Cord Injury: An Updated Systematic Review (P14-7.004)

<h3>Objective:</h3> To conduct a systematic review to evaluate the effects of Mean Arterial Pressure (MAP) or Spinal Cord Perfusion Pressure (SCPP) support on neurological recovery and rates of adverse events among patients with acute traumatic spinal cord injury (SCI). <h3>Background:</h3> Interventions that aim to optimize spinal cord perfusion are thought to play an important role in minimizing secondary ischemic damage and improving outcomes in patients with acute traumatic SCIs. However, exactly how to optimize spinal cord perfusion and enhance neurologic recovery remains controversial. <h3>Design/Methods:</h3> We searched PubMed/MEDLINE, EMBASE and ClinicalTrials.gov. Two reviewers independently screened articles, extracted data, and evaluated risk of bias. We implemented the GRADE approach to rate confidence in the quality of the evidence. <h3>Results:</h3> From 569 potentially relevant new citations since 2019, we identified 9 new studies for inclusion, which were combined with 19 studies from a prior review to give a total of 28 studies. According to low or very low quality evidence, the effect of MAP support on neurological recovery is uncertain, and increased SCPP may be associated with improved neurological recovery. Both approaches may involve risks for specific adverse events, but the severity of these events and their importance to patients remains unclear. Very low quality evidence failed to yield reliable guidance about particular monitoring techniques, perfusion ranges, pharmacological agents, or durations of treatment. <h3>Conclusions:</h3> This update provides an evidence base to support the development of a new clinical practice guideline for the hemodynamic management of patients with acute traumatic SCI. While avoidance of hypotension and maintenance of spinal cord perfusion are important principles in the management of an acute SCI, the literature does not provide high quality evidence in support of a particular protocol. Further prospective, controlled research studies with objective validated outcome assessments are required to examine interventions to optimize spinal cord perfusion in this setting. <b>Disclosure:</b> An immediate family member of Dr. Kahn has received personal compensation for serving as an employee of Essai. Dr. Tetreault has nothing to disclose.

103 Cerebrospinal Fluid Drainage in Acute Spinal Cord Injury: A Multi-Center, Randomized, Controlled Trial

INTRODUCTION: The devastating sequelae of spinal cord injury (SCI) are worsened by ischemia and inflammation that occur following the primary mechanical damage to the cord. Optimizing spinal cord perfusion pressure (SCPP), calculated as the difference between mean arterial pressure (MAP) and intrathecal pressure (ITP), may improve long-term neurological outcomes. MAP augmentation is frequently used to improve perfusion; however, the efficacy of ITP reduction is less clear. METHODS: Patients with acute cervical SCI presenting within 24 hours were screened for eligibility. All patients received lumbar drain placement and appropriate decompressive surgery. Patients in the control group received MAP elevation only, while patients in the interventional group received MAP elevation and CSFD for a target ITP of below 10 mm Hg for 5 days. ITP and MAP were recorded hourly. Patients underwent functional assessments at enrollment, 72 hours, 90 days, and 180 days after injury. RESULTS: A total of 11 patients were enrolled, and four were randomized to receive CSFD. Patients in the CSFD cohort had a mean ITP of 5.3 ± 2.5 mm Hg compared to 15 ± 3.0 mm Hg in the control group. SCPP improved significantly from 77 ± 4.5 mm Hg in the control group to 101 ± 6.3 mm Hg in the experimental group (p &lt; 0.01). Total motor scores improved by 15 ± 8.4 points and 57 ± 24 points in the control and CSFD groups, respectively, over 180 days. No adverse events were attributable to CSFD. CONCLUSIONS: CSFD is feasible and an effective mechanism for reducing ITP and improving SCPP in the acute period after SCI. The complication profile was similar between both groups, and long-term improvements in motor and sensory function were seen with CSFD.

Mechanism of Increased Spinal Cord Blood Flow due to Noradrenaline Administration Using Vascular Resistance: An Experimental Study Using a Canine Model

During thoracoabdominal aortic surgery, the spinal cord is placed under ischemic conditions. Elevation of systemic blood pressure is thus recommended as a method of increasing the blood supply from collateral networks. This study examined the mechanisms by which noradrenaline administration increases spinal cord blood flow (SCBF) by elevating systemic blood pressure. In beagles (n = 7), the thoracoabdominal aorta and L2-L7 spinal cord segmental arteries (SAs) were exposed and a distal perfusion bypass was created to simulate clinical practice. SCBF was measured by laser flowmetry at the L5 dura mater and spinal cord perfusion pressure (SCPP) was measured inside the clamped aorta. The six pairs of SAs from L2 to L7 were clamped, and mean systemic blood pressure (mSBP), SCBF, and SCPP were measured before and after clamping and after starting continuous infusion of noradrenaline at 0.5 µg/kg/min. Rates of change in systemic vascular resistance (SVR) and spinal cord vascular resistance (SCVR) were calculated from the measured values. With no SA clamping (control), the rate of increase in SCVR was 0.74 times the rate of increase in SVR (y = 0.2 + 0.74x, r = 0.889, r2 = 0.789; P < 0.01). When all six pairs of SAs were clamped, a weak correlation was evident between rate of change in SCVR and rate of change in SVR, and the rate of increase in SCVR was lower than the rate of increase in SVR (y = 0.39 + 0.07x, r = 0.209, r2 = 0.039; P < 0.01). When all six pairs of SAs were clamped in the absence of distal perfusion, a weak correlation was also evident between rate of change in SCVR and rate of change in SVR, and the rate of increase in SCVR was lower than the rate of increase in SVR (y = 0.19 + 0.08x, r = 0.379, r2 = 0.144; P < 0.01). The rate of increase in SCVR induced by noradrenaline administration was lower than the rate of increase in SVR in the control group with no spinal cord SA clamping and in both experimental groups with clamped SAs (with and without distal perfusion), creating an environment conducive to spinal cord flow distribution.

Near-infrared spectroscopy to monitor spinal cord oxygenation in οpen thoraco-abdominal aortic surgery. A case series

Objectives. We adopted the near-infrared spectroscopy (NIRS) technology to monitor the spinal oxygen supply through the paraspinous muscles oxygenation in agreement with the concept of “collateral network” circulation. We retrospectively investigated our database of subjects who underwent thoraco-abdominal aorta open repair assessing for the reliability of this monitoring to predict spinal cord injury. Methods. Consecutive patients who underwent elective thoraco-abdominal aorta open repair between March 2019 and September 2021. In addition to standard monitoring, patients received the monitoring of the paraspinous muscles oxygenation by NIRS. Results. In one patient a significant drop of the mean arterial pressure (49 mmHg) and the spinal-cord perfusion pressure (31 mmHg) occurred after the aortic clamping, with a contemporary lowering of the left-side oxygenation of paraspinous muscles (&lt;40%). Both the blood pressure and the spinal cord perfusion pressure were restored within 10 minutes, but the oxygenation remained at an unsafe level (&lt;55%) until the end of the surgery. This same patient experienced a lower-limb paralysis post-operatively. It did not happen in the other 11 cases of the sample. Conclusions. The main finding of our retrospective analysis indicates reliability of this technology to monitor the spinal cord oxygenation during open thoraco-abdominal aortic surgery and possibly predict spinal cord injury. Still, several questions need to be addressed about the suitability of this technology to the anatomic and pathophysiology of the spinal cord circulation

Multimodal interventions to optimize spinal cord perfusion in patients with acute traumatic spinal cord injuries: a systematic review.

The authors systematically reviewed current evidence for the utility of mean arterial pressure (MAP), intraspinal pressure (ISP), and spinal cord perfusion pressure (SCPP) as predictors of outcomes after traumatic spinal cord injury (SCI). PubMed, Cochrane Reviews Library, EMBASE, and Scopus databases were queried in December 2020. Two independent reviewers screened articles using Covidence software. Disagreements were resolved by a third reviewer. The inclusion criteria for articles were 1) available in English; 2) full text; 3) clinical studies on traumatic SCI interventions; 4) involved only human participants; and 5) focused on MAP, ISP, or SCPP. Exclusion criteria were 1) only available in non-English languages; 2) focused only on the brain; 3) described spinal diseases other than SCI; 4) interventions altering parameters other than MAP, ISP, or SCPP; and 5) animal studies. Studies were analyzed qualitatively and grouped into two categories: interventions increasing MAP or interventions decreasing ISP. The Scottish Intercollegiate Guidelines Network level of evidence was used to assess bias and the Grading of Recommendations, Assessment, Development, and Evaluation approach was used to rate confidence in the anticipated effects of each outcome. A total of 2540 unique articles were identified, of which 72 proceeded to full-text review and 24 were included in analysis. One additional study was included retrospectively. Articles that went through full-text review were excluded if they were a review paper (n = 12), not a full article (n = 12), a duplicate paper (n = 9), not a human study (n = 3), not in English (n = 3), not pertaining to traumatic SCI (n = 3), an improper intervention (n = 3), without intervention (n = 2), and without analysis of intervention (n = 1). Although maintaining optimal MAP levels is the current recommendation for SCI management, the published literature supports maintenance of SCPP as a stronger indicator of favorable outcomes. Studies also suggest that laminectomy and durotomy may provide better outcomes than laminectomy alone, although higher-level studies are needed. Current evidence is inconclusive on the effectiveness of CSF drainage for reducing ISP. This review demonstrates the importance of assessing how different interventions may vary in their ability to optimize SCPP.

Pro: Fluoroscopic Guidance Should Be Routinely Used to Place Cerebrospinal Fluid Drains for Patients Undergoing Aortic Surgery

PER THE SOCIETY for Vascular Surgery clinical guidelines, use of cerebrospinal fluid drains (CSFDs) should be considered for appropriately-selected patients undergoing extensive aortic repair. 1 Upchurch GR Escobar GA Azizzadeh A et al. Society for Vascular Surgery clinical practice guidelines of thoracic endovascular aortic repair for descending thoracic aortic aneurysms. J Vasc Surg. 2021; 73: 55S-83S Abstract Full Text Full Text PDF PubMed Scopus (90) Google Scholar Use of CSFDs enhances spinal cord perfusion pressure, thus ameliorating the detrimental effects in vulnerable watershed regions caused by the surgical reduction in blood supply, and thereby preventing devastating spinal cord ischemia (SCI). It is important to note that patients who experience SCI after aortic repairs have significantly worse long-term survival than those without this complication. More importantly, patients who have a return of neurologic function after SCI can anticipate similar life expectancy compared to those without SCI. There is plenty of evidence suggesting that prophylactic use of CSFDs in selected high-risk patients undergoing aortic repairs reduces the incidence of postoperative SCI. 2 DeSart K Scali ST Feezor RJ et al. Fate of patients with spinal cord ischemia complicating thoracic endovascular aortic repair. J Vasc Surg. 2013; 58 (e2): 635-642 Abstract Full Text Full Text PDF PubMed Scopus (77) Google Scholar A recent meta-analysis that included 3,561 patients from 34 studies, demonstrated a lower incidence of SCI when CSFDs were placed routinely, as opposed to use only in patients meeting specified criteria. 3 Zhang Z Zhou Y Lin S et al. Systematic review and meta-analysis of association of prophylactic cerebrospinal fluid drainage in preventing spinal cord ischemia after thoracic endovascular aortic repair. J Vasc Surg. 2022; 75 (e5): 1478-1489 Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar Hence, the use of CSFDs will be warranted in selected patients undergoing aortic repairs who are at a high risk of SCI. 4 Arora H Ullery BW Kumar PA et al. Pro: Patients at risk for spinal cord ischemia after thoracic endovascular aortic repairs should receive prophylactic cerebrospinal fluid drainage. J Cardiothorac Vasc Anesth. 2015; 29: 1376-1380 Abstract Full Text Full Text PDF PubMed Scopus (9) Google Scholar Although CSFDs are an essential tool in the prevention of SCI caused by the surgery, CSFD placement is not without risk. Rong et al. published a meta-analysis that included 4,714 patients across 34 studies who underwent open and endovascular aortic repairs with CSFDs. 5 Rong LQ Kamel MK Rahouma M et al. Cerebrospinal-fluid drain-related complications in patients undergoing open and endovascular repairs of thoracic and thoraco-abdominal aortic pathologies: a systematic review and meta-analysis. Br J Anaesth. 2018; 120: 904-913 Abstract Full Text Full Text PDF PubMed Scopus (49) Google Scholar This analysis focused on CSFD-related complications, with a 6.5% rate of pooled events, 2.5% of which represented severe complications, including epidural hematoma, intracranial hemorrhage, subarachnoid hemorrhage, meningitis, and/or catheter-related neurologic deficit. Risk factors for increased technical difficulty or even failed CSFD placement included atypical anatomy, such as from prior lumbar spine surgery, osteoarthritis or scoliosis, and poor surface landmarks, as can occur with a higher body mass index. 6 Awad H Ramadan ME Tili E et al. Fluoroscopic-guided lumbar spinal drain insertion for thoracic aortic aneurysm surgery. Anesth Analg. 2017; 125: 1219-1222 Crossref PubMed Scopus (4) Google Scholar

Proposal of a Management Algorithm to Predict the Need for Expansion Duraplasty in American Spinal Injury Association Impairment Scale Grades A-C Traumatic Cervical Spinal Cord Injury Patients.

Expansion duraplasty to reopen effaced subarachnoid space and improve spinal cord perfusion, autoregulation, and spinal pressure reactivity index (sPRX) has been advocated in patients with traumatic cervical spinal cord injury (tCSCI). We designed this study to identify candidates for expansion duraplasty, based on the absence of cerebrospinal fluid (CSF) interface around the spinal cord on magnetic resonance imaging (MRI), in the setting of otherwise adequate bony decompression. Over a 61-month period, 104 consecutive American Spinal Injury Association Impairment Scale (AIS) grades A-C patients with tCSCI had post-operative MRI to assess the adequacy of surgical decompression. Their mean age was 53.4 years, and 89% were male. Sixty-one patients had falls, 31 motor vehicle collisions, 11 sport injuries, and one an assault. The AIS grade was A in 56, B in 18, and C in 30 patients. Fifty-four patients had fracture dislocations; there was no evidence of skeletal injury in 50 patients. Mean intramedullary lesion length (IMLL) was 46.9 (standard deviation = 19.4) mm. Median time from injury to decompression was 17 h (interquartile range 15.2 h). After surgery, 94 patients had adequate decompression as judged by the presence of CSF anterior and posterior to the spinal cord, whereas 10 patients had effacement of the subarachnoid space at the injury epicenter. In two patients whose decompression was not definitive and post-operative MRI indicated inadequate decompression, expansion duraplasty was performed. Candidates for expansion duraplasty (i.e., those with inadequate decompression) were significantly younger (p < 0.0001), were AIS grade A (p < 0.0016), had either sport injuries (six patients) or motor vehicle collisions (three patients) (p < 0.0001), had fracture dislocation (p = 0.00016), and had longer IMLL (p = 0.0097). In regression models, patients with sport injuries and inadequate decompression were suitable candidates for expansion duraplasty (p = 0.03). Further, 9.6% of patients failed bony decompression alone and either did (2) or would have (8) benefited from expansion duraplasty.

The acute phase management of spinal cord injury affecting polytrauma patients: the ASAP study

BackgroundFew data on the management of acute phase of traumatic spinal cord injury (tSCI) in patients suffering polytrauma are available. As the therapeutic choices in the first hours may have a deep impact on outcome of tSCI patients, we conducted an international survey investigating this topic.MethodsThe survey was composed of 29 items. The main endpoints of the survey were to examine: (1) the hemodynamic and respiratory management, (2) the coagulation management, (3) the timing of magnetic resonance imaging (MRI) and spinal surgery, (4) the use of corticosteroid therapy, (5) the role of intraspinal pressure (ISP)/spinal cord perfusion pressure (SCPP) monitoring and (6) the utilization of therapeutic hypothermia.ResultsThere were 171 respondents from 139 centers worldwide. A target mean arterial pressure (MAP) target of 80–90 mmHg was chosen in almost half of the cases [n = 84 (49.1%)]. A temporary reduction in the target MAP, for the time strictly necessary to achieve bleeding control in polytrauma, was accepted by most respondents [n = 100 (58.5%)]. Sixty-one respondents (35.7%) considered acceptable a hemoglobin (Hb) level of 7 g/dl in tSCI polytraumatized patients. An arterial partial pressure of oxygen (PaO2) of 80–100 mmHg [n = 94 (55%)] and an arterial partial pressure of carbon dioxide (PaCO2) of 35–40 mmHg [n = 130 (76%)] were chosen in most cases. A little more than half of respondents considered safe a platelet (PLT) count > 100.000/mm3 [n = 99 (57.9%)] and prothrombin time (PT)/activated partial thromboplastin time (aPTT) < 1.5 times the normal control [n = 85 (49.7%)] in patients needing spinal surgery. MRI [n = 160 (93.6%)] and spinal surgery [n = 158 (92.4%)] should be performed after intracranial, hemodynamic, and respiratory stabilization by most respondents. Corticosteroids [n = 103 (60.2%)], ISP/SCPP monitoring [n = 148 (86.5%)], and therapeutic hypothermia [n = 137 (80%)] were not utilized by most respondents.ConclusionsOur survey has shown a great worldwide variability in clinical practices for acute phase management of tSCI patients with polytrauma. These findings can be helpful to define future research in order to optimize the care of patients suffering tSCI.

All over the MAP: describing pressure variability in acute spinal cord injury.

Observational study. To examine the feasibility of meeting the current clinical guidelines for the hemodynamic management of acute spinal cord injury (SCI) which recommend maintaining mean arterial pressure (MAP) at 85-90 mmHg in the days following injury. This study examined data collected minute-by-minute to describe the pressure profile in the first 5 days following SCI in 16 patients admitted to the Intensive Care Unit at Vancouver General Hospital (40 ± 19 years, 13 M/3 F, C4-T11). MAP and intrathecal pressure (ITP) were monitored at 100 Hz by arterial and lumbar intrathecal catheters, respectively, and reported as the average of each minute. Spinal cord perfusion pressure was calculated as the difference between MAP and ITP. The minute-to-minute difference (MMdiff) of each pressure variable was calculated as the absolute difference between consecutive minutes. Only 24 ± 7% of MAP recordings were between 85 and 90 mmHg. Average MAP MMdiff was ~3 mmHg. The percentage of MAP recordings within target range was negatively correlated with the degree of variability (i.e. MMdiff; r = -0.64, p < 0.008) whereas higher mean MAP was correlated with greater variability (r = 0.57, p = 0.021). Our findings point to the 'real life' challenges in maintaining MAP in acute SCI patients. Given MAP fluctuated ~3 mmHg minute-to-minute, maintaining MAP within a 5 mmHg range with conventional volume replacement and vasopressors presents an almost impossible task for clinicians and warrants reconsideration of current management guidelines.

Monitoring Spinal Cord Tissue Oxygen in Patients With Acute, Severe Traumatic Spinal Cord Injuries.

To determine the feasibility of monitoring tissue oxygen tension from the injury site (pscto2) in patients with acute, severe traumatic spinal cord injuries. We inserted at the injury site a pressure probe, a microdialysis catheter, and an oxygen electrode to monitor for up to a week intraspinal pressure (ISP), spinal cord perfusion pressure (SCPP), tissue glucose, lactate/pyruvate ratio (LPR), and pscto2. We analyzed 2,213 hours of such data. Follow-up was 6-28 months postinjury. Single-center neurosurgical and neurocritical care units. Twenty-six patients with traumatic spinal cord injuries, American spinal injury association Impairment Scale A-C. Probes were inserted within 72 hours of injury. Insertion of subarachnoid oxygen electrode (Licox; Integra LifeSciences, Sophia-Antipolis, France), pressure probe, and microdialysis catheter. pscto2 was significantly influenced by ISP (pscto2 26.7 ± 0.3 mm Hg at ISP > 10 mmHg vs pscto2 22.7 ± 0.8 mm Hg at ISP ≤ 10 mm Hg), SCPP (pscto2 26.8 ± 0.3 mm Hg at SCPP < 90 mm Hg vs pscto2 32.1 ± 0.7 mm Hg at SCPP ≥ 90 mm Hg), tissue glucose (pscto2 26.8 ± 0.4 mm Hg at glucose < 6 mM vs 32.9 ± 0.5 mm Hg at glucose ≥ 6 mM), tissue LPR (pscto2 25.3 ± 0.4 mm Hg at LPR > 30 vs pscto2 31.3 ± 0.3 mm Hg at LPR ≤ 30), and fever (pscto2 28.8 ± 0.5 mm Hg at cord temperature 37-38°C vs pscto2 28.7 ± 0.8 mm Hg at cord temperature ≥ 39°C). Tissue hypoxia also occurred independent of these factors. Increasing the Fio2 by 0.48 increases pscto2 by 71.8% above baseline within 8.4 minutes. In patients with motor-incomplete injuries, fluctuations in pscto2 correlated with fluctuations in limb motor score. The injured cord spent 11% (39%) hours at pscto2 less than 5 mm Hg (< 20 mm Hg) in patients with motor-complete outcomes, compared with 1% (30%) hours at pscto2 less than 5 mm Hg (< 20 mm Hg) in patients with motor-incomplete outcomes. Complications were cerebrospinal fluid leak (5/26) and wound infection (1/26). This study lays the foundation for measuring and altering spinal cord oxygen at the injury site. Future studies are required to investigate whether this is an effective new therapy.

Acute, severe traumatic spinal cord injury: improving urinary bladder function by optimizing spinal cord perfusion.

The authors sought to investigate the effect of acute, severe traumatic spinal cord injury on the urinary bladder and the hypothesis that increasing the spinal cord perfusion pressure improves bladder function. In 13 adults with traumatic spinal cord injury (American Spinal Injury Association Impairment Scale grades A-C), a pressure probe and a microdialysis catheter were placed intradurally at the injury site. We varied the spinal cord perfusion pressure and performed filling cystometry. Patients were followed up for 12 months on average. The 13 patients had 63 fill cycles; 38 cycles had unfavorable urodynamics, i.e., dangerously low compliance (< 20 mL/cmH2O), detrusor overactivity, or dangerously high end-fill pressure (> 40 cmH2O). Unfavorable urodynamics correlated with periods of injury site hypoperfusion (spinal cord perfusion pressure < 60 mm Hg), hyperperfusion (spinal cord perfusion pressure > 100 mm Hg), tissue glucose < 3 mM, and tissue lactate to pyruvate ratio > 30. Increasing spinal cord perfusion pressure from 67.0 ± 2.3 mm Hg (average ± SE) to 92.1 ± 3.0 mm Hg significantly reduced, from 534 to 365 mL, the median bladder volume at which the desire to void was first experienced. All patients with dangerously low average initial bladder compliance (< 20 mL/cmH2O) maintained low compliance at follow-up, whereas all patients with high average initial bladder compliance (> 100 mL/cmH2O) maintained high compliance at follow-up. We conclude that unfavorable urodynamics develop within days of traumatic spinal cord injury, thus challenging the prevailing notion that the detrusor is initially acontractile. Urodynamic studies performed acutely identify patients with dangerously low bladder compliance likely to benefit from early intervention. At this early stage, bladder function is dynamic and is influenced by fluctuations in the physiology and metabolism at the injury site; therefore, optimizing spinal cord perfusion is likely to improve urological outcome in patients with acute severe traumatic spinal cord injury.

P.187 Evaluating congruency between intramedullary and subdural pressure in a porcine model of acute spinal cord injury

Background: Clinical guidelines recommend MAP maintenance at 85-90 mmHg to optimize spinal cord perfusion post-SCI. Recently, there has been increased interest in spinal cord perfusion pressure as a surrogate marker for spinal cord blood flow. The study aims to determine the congruency of subdural and intramedullary spinal cord pressure measurements at the site of SCI, both rostral and caudal to the epicenter of injury. Methods: Seven Yucatan pigs underwent a T5 to L1 laminectomy with intramedullary (IM) and subdural (SD) pressure sensors placed 2 mm rostral and 2 mm caudal to the epicenter of SCI. A T10 contusion SCI was performed followed by an 8-hour period of monitoring. Axial ultrasound images were captured at the epicenter of injury pre-SCI, post-SCI, and hourly thereafter. Results: Pigs with pre-SCI cord to dural sac ratio (CDSR) of &gt;0.8 exhibited greater occlusion of the subdural space post-SCI with a positive correlation between IM and SD pressure rostral to the injury and a negative correlation caudal to the epicenter. Pigs with pre-SCI CDSR &lt;0.8 exhibited no correlation between IM and SD pressure. Conclusions: Congruency of IM and SD pressure is dependent on compartmentalization of the spinal cord occurring secondary to swelling that occludes the subdural space.

Medical Communication Services after Traumatic Spinal Cord Injury.

It is difficult to assess and monitor the spinal cord injury (SCI) because of its pathophysiology after injury, with different degrees of prognosis and various treatment methods, including laminectomy, durotomy, and myelotomy. Medical communication services with different factors such as time of surgical intervention, procedure choice, spinal cord perfusion pressure (SCPP), and intraspinal pressure (ISP) contribute a significant role in improving neurological outcomes. This review aims to show the benefits of communication services and factors such as ISP, SCPP, and surgical intervention time in order to achieve positive long-term outcomes after an appropriate treatment method in SCI patients. The SCPP was found between 90 and 100 mmHg for the best outcome, MAP was found between 110 and 130 mmHg, and mean ISP is ≤20 mmHg after injury. Laminectomy alone cannot reduce the pressure between the dura and swollen cord. Durotomy and duroplasty considered as treatment choices after severe traumatic spinal cord injury (TSCI).