Naloxone infusion and drainage of cerebrospinal fluid as adjuncts to postoperative care after repair of thoracoabdominal aneurysms

The mechanisms that produce paraplegia in patients after TAA repair are complex and involve alterations in regional blood flow to the spinal cord, CSF dynamics, and reperfusion. Although neither the minimal level of blood flow nor the maximal spinal cord pressure that can be tolerated by the spinal cord is known, adjuncts such as CSF drainage and naloxone infusions may allow longer durations of aortic cross-clamping before irreversible ischemia occurs. Because paraplegia is multifactorial and none of the recommended adjuncts alone provides complete protection of the spinal cord, a combination of treatments may be necessary to reduce the prevalence of neurological complications after thoracoabdominal aortic reconstruction. Critical care nurses thus must be acquainted with the advanced monitoring techniques and the pathophysiology behind these new treatment modalities. Advanced assessment skills are also essential to recognize the potential neurological complications that may occur in these patients. Care of patients with TAA is a challenge. Critical care nurses must use multidimensional skills in the areas of hemodynamic monitoring, physical assessment, and psychological counseling to effectively manage postoperative care of these patients.     

Spinal Cord Infarction Caused by Non-dissected and Unruptured Thoracoabdominal Aortic Aneurysm with Intraluminal Thrombus

Spinal cord infarction, especially anterior spinal artery syndrome, is a relatively rare disease. We report a case of spinal cord infarction caused by thoracoabdominal aortic aneurysm with intraluminal thrombus. A 52-year-old man presented with sudden onset paraplegia. At first, he was diagnosed with cervical myelopathy due to a C6-7 herniated intervertebral disc, and had an operation for C6-7 discetomy and anterior interbody fusion. Approximately 1 month after the operation, he was transferred to the department of rehabilitation in our hospital. Thoracoabdominal aortic aneurysm with intraluminal thrombus was found incidentally on an enhanced computed tomography scan, and high signal intensities were detected at the anterior horns of gray matter from the T8 to cauda equina level on T2-weighted magnetic resonance imaging. There was no evidence of aortic rupture, dissection, or complete occlusion of the aorta. We diagnosed his case as a spinal cord infarction caused by thoracoabdominal aortic aneurysm with intraluminal thrombus.     

Complications arising after thoracic aortic surgery: A case report on an unusual spinal cord infarction. Physiopathological and clinical considerations

Even though new prevention techniques have been developed and are being used during thoraco-abdominal aortic repairs, spinal cord infarction remains a severe and relatively frequent complication of aortic surgery. Infarctions in the territory of the anterior spinal artery are considered the most common. Different clinical pictures related to spinal cord transverse extension wounds are drawn up. In this paper, we present a case report of a subject having presented an isolated motor deficit of the lower limbs and a favorable prognosis, suggesting selective involvement of the anterior horns of the spinal cord subsequent to surgical repair of an aortic dissection. We wish to review the relevant anatomical, clinical and diagnostic characteristics along with current techniques of spinal cord ischemia prevention during and after surgery.     

Ischemic injury to the spinal cord as a cause of transient paraplegia

Spinal cord ischemia presenting as acute paraplegia is an uncommon occurrence not previously reported in the emergency medicine literature. Paraplegia due to spinal ischemia is seen most commonly after intraoperative aortic manipulation; however, acute hypotension and prolonged cardiopulmonary resuscitation are also reported settings. The differential diagnosis of acute, non-traumatic paraplegia includes mechanical spinal cord compression, acute transverse myelitis, and polyneuritis.     

脊髓动脉的影像显示方法与临床应用

脊髓动脉细小,解剖复杂,临床病种多样,术前了解其解剖结构,可以制定适宜的手术方案,减少术中脊髓缺血性损害及术后脊髓截瘫等并发症。影像学检查是了解脊髓动脉的重要手段,本文综述脊髓动脉的影像显示方法及临床应用。     

Thoracoabdominal aortic aneurysm repair: historical review and description of a re-engineered technique

Most complications related to thoracoabdominal aortic reconstruction stem from ischemia-induced injury to the viscera, kidneys, and spinal cord. Pioneers in the treatment of thoracoabdominal aortic aneurysms recognized the danger of producing ischemic damage to these vital organs. In addition to adjunctive methods designed to minimize metabolic demands of the spinal cord during aortic cross-clamping, a variety of extracorporeal techniques have been developed that provide supplemental blood flow to vital end organs during the period of clamp-induced ischemia. This article reviews these extracorporeal methods and provides a historical perspective of thoracoabdominal aortic aneurysm repair. In addition, a reengineered technique for thoracoabdominal aortic aneurysm repair is highlighted.     

Spinal cord preservation in thoracoabdominal aneurysm repair

Spinal cord injury (SCI) stands as one of the most dreadful complications of thoracoabdominal aneurysm repair. Despite the less invasive nature and recent technical advancements of endovascular aortic repair, SCI still remains a significant danger in endovascular approaches. However, as our understanding of the collateral network of spinal cord vasculature has grown, it has become evident that the incidence of paraplegia and paraparesis in conjunction with endovascular procedures can be minimized through the use of many of the same strategies that have proven successful in reducing SCI associated with open surgical repair. This article highlights important aspects of spinal cord protection, which have been derived from the authors' clinical and experimental experience.     

Prevention of spinal cord ischemia in an ovine model of abdominal aortic aneurysm treated with a self-expanding stent-graft.

PURPOSE: To present novel techniques to prevent spinal ischemia during aneurysm creation and chronic bifurcated stent-graft implantation in an ovine model of abdominal aortic aneurysm (AAA). METHOD: Experimental AAAs were created in 38 sheep. To prevent spinal ischemia, an internal aortic shunt was used during aneurysm creation. In the animals designated to receive bifurcated stent-grafts, a left external iliac-to-internal iliac bypass was performed to revascularize the caudal artery and prevent postdeployment spinal cord ischemia. Specimens were harvested at 1 week, 1, 3, and 6 months, and 1 year. RESULTS: Aneurysms were successfully created without paralysis in 35 animals. Two died due to aspiration pneumonia. Of the 33 animals implanted with endografts, 16 (94%) of 17 with straight devices and 15 (94%) of 16 with bifurcated stent-grafts survived with well-functioning, patent stent-grafts. Paralysis developed in 2 animals after endografting due to technical failures. CONCLUSIONS: The use of an internal shunt during aneurysm creation and internal iliac-to-external iliac transposition prior to bifurcated stent-graft deployment prevented spinal ischemia in an ovine AAA model. Chronically deployed stent-grafts were well tolerated.     

The effect of adjuvant perfusion techniques on the incidence of paraplegia after repair of traumatic thoracic aortic transections

OBJECTIVE: To analyze the effect of adjuvant perfusion techniques of the distal aorta on the outcome of traumatic thoracic aortic transections. PATIENTS AND METHODS: From 1973 to 2004, 72 patients (mean age, 39 years) with thoracic aortic transections arrived alive at the emergency department. Nineteen patients arrived in extremis and underwent emergency operations, 42 patients were stable and underwent diagnostic evaluation before surgery (4 patients experienced aortic rupture during evaluation), and 11 patients presented more than 24 hours after the accident. Sixteen patients died before aortic repair could be performed. Operative repair was possible in 53 patients (46 stable and 7 in extremis). Interposition graft was performed in 47 patients, and primary repair was performed in 6 patients. Morbidity, mortality, and paraplegia rate were analyzed. RESULTS: Patients in extremis had a mortality rate of 84% (16 of 19), stable patients had a mortality rate of 11% (4 of 38), patients who experienced rupture during evaluation had a mortality rate of 100% (4 of 4), and patients who underwent delayed operation had a mortality rate of 0% (0 of 11). The paraplegia rate with and without adjuvant distal aortic perfusion techniques was 2% (1 of 41 patients) and 33% (4 of 12 patients), respectively (P=.007). Mortality and paraplegia rates were 4% and 4% for partial bypass (n=24), 42% and 33% for the clamp and sew technique (n=12), 0% and 0% for Gott shunt (n=10), and 29% and 0% for full cardiopulmonary bypass (n=7), respectively. CONCLUSIONS: Although thoracic aortic transections remain a highly lethal injury, hemodynamically stable patients have a low operative mortality. Spinal cord injury is decreased by the use of adjuvant perfusion techniques that maintain distal aortic perfusion during cross-clamping of the aorta.     

Experimental spinal cord ischemia: model characterization and improved outcome with arterial hypertension

OBJECTIVE: Paraplegia from spinal cord ischemia is a devastating complication of thoracoabdominal aortic aneurysm repair. Perioperative hypoperfusion of the spinal cord is a critical determinant of residual neurologic deficits. We determined if functional and histologic outcome is dependent on systemic blood pressure in a rat model of spinal cord ischemia. DESIGN: Randomized, controlled, prospective study. SETTING: Research laboratory at a university teaching hospital. SUBJECTS: Adult male Wistar rats. INTERVENTIONS: Endotracheally intubated adult male Wistar rats (300-450 g) anesthetized with halothane underwent a thoracotomy and placement of a clip across the descending aorta for 27 mins. Mean proximal arterial blood pressure (MPABP) was monitored with a cannula placed in the left common carotid artery. Halothane was adjusted (1.25-1.5%) to maintain MPABP between 70 and 90 mm Hg (n = 20) or 140 and 150 mm Hg (n = 20). Shamoperated rats (n = 10) had a thoracotomy without aortic clamping at an MPABP of 70-90 mm Hg. Following 1, 24, 48, and 72 hrs of recovery from anesthesia, motor function of the hind paws was scored as follows: 0, no evidence of deficit; 1, toes flat under body when walking but with ataxia; 2, knuckle walks; 3, movements in hind limbs but unable to knuckle walk; 4, no movement, drags hind limbs. Body temperature was maintained between 37 and 38 degrees C throughout the experiment. MEASUREMENTS AND MAIN RESULTS: All sham operated rats with MPABP 70-90 mm Hg recovered without neurologic deficits, whereas those that underwent aortic occlusion with MPABP between 70 and 90 mm Hg emerged from anesthesia with grade 3 and 4 deficits and remained in this condition without improvement at 72 hrs. Histopathology at 72 hrs demonstrated moderate to severe neuronal loss with involvement of dorsal, intermediate, and ventral horns. Only eight of 20 rats that underwent aortic occlusion with MPABP between 140 and 150 mm Hg had grade 1 and 2 deficits on emergence but had no neurologic deficit after 1 hr. Most of the surviving neurons in these animals appeared normal histologically, particularly motor neurons around the periphery of the ventral horn. CONCLUSIONS: Systemic blood pressure is a critical determinant of outcome following spinal cord ischemia, and controlled peri-operative blood pressure augmentation may ameliorate neurologic deficits in patients who undergo thoracoabdominal vascular procedures and are at risk for spinal cord hypoperfusion.     

Persistent hypertension in young spinal cord injured individuals resulting from aortic repair

The development of persistent hypertension in young, previously healthy paraplegic individuals is unusual; it could be postulated that hypertension is a cardiovascular response peculiar to patients who sustained spinal cord injury after surgical repair of the aorta with trauma-related injuries. In a retrospective study of 712 patients sustaining spinal cord injury during the last decade, seven sustained paraplegia after aortic repair that was necessitated by trauma-related injuries. Despite the low incidence of new-onset hypertension in paraplegic patients, five of the seven developed hypertension, of which three required chronic antihypertensive medications. It is well documented that patients with lesions of the neuraxis above the sixth thoracic segment are prone to the phenomenon of autonomic hyperreflexia. This results from interruption of the baroreceptor reflex and the descending tracts of the spinal cord. There is evidence that the renin-angiotensin system, catecholamines, and receptor-site activity play an important role in the control of blood pressure in spinal cord injured patients. Additional investigation of this rare subgroup of spinal cord injured patients may further illuminate the effect of spinal cord injury on autonomic control of the cardiovascular system.     

Acute rupture of an aortic false aneurysm treated with a stent-graft.

PURPOSE: To report the use of an aortic endograft to treat a ruptured false aneurysm at the anastomosis of an aortofemoral bypass graft. METHODS AND RESULTS: A 68-year-old man with a 30-year-old aorto-right femoral bypass and multiple comorbidities was admitted to the hospital complaining of acute abdominal pain. Imaging identified a 60-mm ruptured aortic false aneurysm with associated retroperitoneal hematoma, a 9-cm right femoral false aneurysm, and a calcified 23-mm left common iliac aneurysm. Two slightly overlapping Vanguard straight stent-grafts were implanted in the aorta and left common iliac artery in an emergency procedure owing to the patient's high surgical risk. The anastomotic false aneurysm and the bypass were excluded. A left-to-right femorofemoral bypass was performed to re-establish flow to the right femoral artery with ligation of the external iliac artery. The patient recovered uneventfully. He remained well with a successful repair until his death of a myocardial infarction 6 months after the procedure. CONCLUSIONS: Endovascular grafting can be used successfully for the urgent treatment of aortic false aneurysm rupture.     

Anesthesia, changes in hemodynamics and metabolism in surgical treatment of thoracic and abdominal aortic aneurysms

45 patients aged 32-63 years operated on for dissecting aneurysm of the thoracoabdominal part of the aorta were divided into 2 groups. Group 1 patients (n = 36) were operated on with application of the bypass using centrifuge pump. Group 2 patients (n = 9) were operated on without the bypass. The results evidence that the employed anesthesia and infusion therapy in combination with the bypass maintained by the pump provide stable intraoperative hemodynamics and prevent renal failure. Usage of the bypass in combination with liquor drainage reliably protects spinal cord from ischemia, especially in patients with long-term aortic ligature.     

胸腹主动脉夹层手术脊髓损伤标记物临床研究

目的探讨脑脊液生化指标监测对胸腹主动脉夹层术后脊髓缺血损害判断的临床意义。方法将50例胸腹主动脉夹层手术患者根据术后是否发生脊髓缺血损害并发症分成损伤组（SCI组,n=5）和无损伤组（NSCI组,n=45）。术前、术后分7个时点对脑脊液取样,对胶质纤维酸蛋白（GFAP）、S100β蛋白以及神经丝蛋白亚单位（NFL）等3个生化指标进行测定。比较分析上述3个生化指标在2组之间的变化。将无脊髓损伤患者据术式分为血管置换手术组（AR组,n=9）和腔内隔绝术组（EVGE组,n=36）,同样比较分析上述3个生化指标在2组之间的差异。结果 SCI组术后6 h各项生化指标开始升高,48-72 h各项指标明显高于NSCI组（P〈0.01）。术后6 h以后GFAP、S100β蛋白测定数值在2组之间数值无重叠。腔内隔绝术后各项指标无明显升高,血管置换术后6 h起GFAP、S100β开始升高,术后24 h达到峰值,较术前相比差异有统计学意义（P〈0.05）,同时高于腔内隔绝术后对应时点。血管置换术后（第24h4、8 h）时点NFL高于腔内隔绝术后对应时点（P〈0.05）。结论脑脊液生化指标持续监测可以预判迟发性脊髓损害。GFAP、S100β蛋白比NFL诊断脊髓损伤有更高的预测价值。     

分期全主动脉置换术治疗主动脉夹层动脉瘤

目的:探讨采用分期全主动脉置换术治疗主动脉夹层动脉瘤的手术方式和治疗效果。方法:对6例马凡氏综合征的患者行分期全主动脉置换术,手术方法为:经左侧胸腹联合切口、腹膜外入路,在体外循环或左心转流下采用分段阻断法完成胸腹主动脉置换及重要分支的重建。其中1例深体温停循环20 min。结果:所有患者均康复出院,平均体外循环或左心转流时间(202.0±54.1)min,呼吸机辅助通气时间10.5～200.0h,患者监护室入住时间3～12 d。术后出现急性肾功能损害2例,声音嘶哑2例,无脊髓损伤病例。1例术后2个月因脓胸病死。结论:分期全主动脉置换术是治疗主动脉夹层动脉瘤的一种安全、有效的方法。     

腹主动脉瘤腔内修复治疗的进展

腹主动脉瘤（Abdominal aortic aneurysm,AAA）是指腹主动脉局限性瘤样扩张,超过3cm或超过正常直径的50%即可诊断为腹主动脉瘤,75%的患者并无临床症状〔1〕,破裂是其最常见、最凶险的并发症,破裂后的死亡率高达80%~90%〔2〕。     

Paraplegia after aortic aneurysm repair versus traumatic spinal cord injury: functional outcome, complications, and therapy intensity of inpatient rehabilitation

Yokoyama O, Sakuma F, Itoh R, Sashika H. Paraplegia after aortic aneurysm repair versus traumatic spinal cord injury: functional outcome, complications, and therapy intensity of inpatient rehabilitation.

Objective

To compare outcomes, complications, and therapy intensity of inpatient rehabilitation in patients with paraplegia caused by spinal cord injury associated with aortic aneurysm repair (SCI-AA) versus patients with traumatic spinal cord injury (SCI).

Design

Case-controlled study.

Setting

SCI unit in a rehabilitation center.

Participants

Seventeen patients with SCI-AA and 17 patients with traumatic SCI.

Intervention

Standard rehabilitation therapy for SCI.

Main Outcome Measures

Length of stay (LOS) in acute and rehabilitation hospitals; FIM instrument scores; FIM change; FIM efficiency; complications; therapy intensity; and ambulatory state and return to community at discharge.

Results

No significant differences were noted in acute and rehabilitation LOS and admission FIM scores. Discharge FIM scores, FIM change, and FIM efficiencies were significantly lower in the SCI-AA group, which had many complications related to AA and SCI. Intensity of rehabilitation sports therapy in the SCI-AA group was significantly lower than that of the traumatic SCI group, but total therapy intensity did not differ significantly. Both had similar rates of return to ambulatory state and discharge to the community.

Conclusions

SCI-AA patients had many complications that interfered with rehabilitation therapy, and could not achieve functional gains comparable to those with traumatic SCI. However, both groups achieved comparable success with return to ambulatory state and discharge to the community.     

Man With Sudden Paralysis: Insidious Spinal Cord Infarction due to a Non-Ruptured Abdominal Aortic Aneurysm

Background

Acute infarctions of the spinal cord are rare events characterized by sudden paralysis or sensory deficits below the level of injury. Etiologies include spinal cord trauma, vascular injury, arterial dissection, thromboembolic disease, chronic inflammatory conditions, or mass effect on the spinal cord.

Thoracic endovascular stent graft placement: a case report

Endovascular stent grafting (EVSG) is a minimally invasive alternative to open repair of thoracic aortic aneurysms. It is useful in the treatment of thoracic aneurysms, dissections, and ruptures. Currently, the incidence of thoracic aortic aneurysms is 6:100,000 people. Comorbidities often include hypertension, coronary artery disease, chronic obstructive pulmonary disease, peripheral vascular disease, and cerebrovascular disease, and there often is a history of smoking. Without surgical intervention, a high risk of mortality exists, primarily due to aneurysm rupture. Due to the complexity of performing open surgical repair of the thoracic aorta and its associated morbidities such as paraplegia, renal failure, stroke, and prolonged ventilator support, new approaches to thoracic aneurysm repair are being investigated. When compared with open repair, stent grafting is a palliative rather than a curative treatment, and the risk of aneurysmal rupture still exists. This article describes a patient who underwent EVSG who had a history of abdominal aortic aneurysm repair and a known bovine arch.     

Epidural cooling for spinal cord protection during thoracoabdominal aortic aneurysm repair (a case study)

Aneurysms result from damage to artery walls as a result of underlying athrosclerotic and/or thromboembolic disorders. A thoracoabdominal aortic aneurysm involves vessel damage and wall weakening in the thoracic and abdominal segments of the aorta. Thoracoabdominal aortic aneurysm repair is considered to be high risk due to the nature of the intervention that requires an extensive incision with clamping of the thoracic aorta above the renal arteries. Clamping of the aorta renders all areas distal to the clamp at high risk for ischemic trauma especially to the spinal cord where the risk of neurological deficits postoperatively is 7-16% (Cambria, et al., 1997; Davison, et al., 1997). Several adjunct interventions have been tried to reduce the risk of spinal cord injury associated with the ischemia of cross clamping. Epidural cooling has been successful as an adjunct in reducing the neurological deficits. A preoperative nursing assessment indicating the appropriate nursing diagnoses and nursing care required for this patient, allowed for individualization of the plan needed to include this new procedure and plan for best patient outcomes and practices.