Anesthetic considerations for patients with acute cervical spinal cord injury

Anesthesiologists work to prevent or minimize secondary injury of the nervous system and improve the outcome of medical procedures.To this end,anesthesiologists must have a thorough understanding of pathophysiology and optimize their skills and equipment to make an anesthesia plan.Anesthesiologists should conduct careful physical examinations of patients and consider neuroprotection at preoperative interviews,consider cervical spinal cord movement and compression during airway management,and suggest awake fiberoptic bronchoscope intubation for stable patients and direct laryngoscopy with manual in-line immobilization in emergency situations.During induction,anesthesiologists should avoid hypotension and depolarizing muscle relaxants.Mean artery pressure should be maintained within 85–90 mmHg（1 mmHg = 0.133 kPa; vasoactive drug selection and fluid management）.Normal arterial carbon dioxide pressure and normal blood glucose levels should be maintained.Intraoperative neurophysiological monitoring is a useful option.Anesthesiologists should be attentive to postoperative respiratory insufficiency（carefully considering postoperative extubation）,thrombus,and infection.In conclusion,anesthesiologists should carefully plan the treatment of patients with acute cervical spinal cord injuries to protect the nervous system and improve patient outcome.

Effect of vocal respiratory training on respiratory function and respiratory neural plasticity in patients with cervical spinal cord injury:a randomized controlled trial

In previous studies,researchers have used singing to treat respiratory function in patients with spinal cord injury.However,few studies have examined the way in which vocal training affects respiratory neural plasticity in patients with spinal cord injury.Vocal respiratory training(VRT)is a type of vocal muscle-related treatment that is often a component of music therapy(MT)and focuses on strengthening respiratory muscles and improving lung function.In this randomized controlled study,we analyzed the therapeutic effects of VRT on respiratory dysfunction at 3 months after cervical spinal cord injury.Of an initial group of 37 patients,26 completed the music therapy intervention,which comprised five 30-minute sessions per week for 12 weeks.The intervention group(n=13)received VRT training delivered by professional certified music therapists.The control group(n=13)received respiratory physical therapy delivered by professional physical therapists.Compared with the control group,we observed a substantial increase in respiratory function in the intervention group after the 12-week intervention.Further,the nerve fiber bundles in the respiratory center in the medulla exhibited a trend towards increased diversification,with an increased number,path length,thickness,and density of nerve fiber bundles.These findings provide strong evidence for the effect of music therapeutic VRT on neural plasticity.This study was approved by the Ethics Committee of China Rehabilitation Research Center(approval No.2020-013-1)on April 1,2020,and was registered with the Chinese Clinical Trial Registry(registration No.Chi CTR2000037871)on September 2,2020.

New perspectives for investigating respiratory failure induced by cervical spinal cord injury

Traumatic cervical spinal cord injury （SCI）, with an annual incidence of 12,000 new cases in USA （NSCISC 2013）, causes devastating locomotor and respiratory paralysis and unfortunately compromises the human patient＇s lifespan. The severity of the injury depends on the degree and the extent of the initial trauma. In fact, respiratory failure is the leading cause of mortality following upper cervical SCI. However, 80% of the injuries are incomplete, allowing some modest spontaneous recovery. To date, no effective treatment is available in order to restore the loss of function.

Microsurgical resection of tumors lateroventral and ventral to the high cervical spinal cord

Background Since there are a complex anatomic structure and vital function in the high cervical spinal cord, it is difficult to remove the tumors lateroventral and ventral to the high cervical spinal cord. This clinical study was undertaken to analyze surgical approaches, manner of tumor resection and postoperative management. Methods Thirty-four patients underwent microsurgical excision of tumors lateroventral and ventral to the high cervical spinal cord by means of three approaches. The tumors comprised mostly Schwannoma and meningioma (88.24%, 30/34) in this group. Tumor volume varied from 3.0 cm×2.5 cm×2.0 cm to 12 cm×3.0 cm×2.5 cm. Of the 34 patients, 4 had dumbbell-shaped tumors growing outside the spinal canal and 7 tumors growing into the intracranium. Results The tumor was totally removed in 32 patients (94.1%). Follow-up for 7 months to 6.4 years (median 3.6 years) showed a recovery of a normal life or work ability in 30 (83.3%) patients. Conclusion Modified operative approaches and microsurgical techniques can raise the rate of total tumor removal and reduce the disability of patients.

Massage Treatment for Spinal cord of Cervical Spondylosis

ＭａｓｓａｇｅＴｒｅａｔｍｅｎｔｆｏｒＳｐｉｎａｌｃｏｒｄｏｆＣｅｒｖｉｃａｌＳｐｏｎｄｙｌｏｓｉｓ￥ＪｉｎＪｉａｈｕａ（ＩｎｓｔｉｔｕｔｅｏｆｏｒｔｈｏｐｅｄｉｃｓａｎｄＴｒａｕｍａｔｏｌｏｇｙ，ＣｈｉｎａＡｃａｄｅｍｙｏｆＴＣＭ．１００７００）Ｔ...

Functional evaluation using several evoked spinal cord potentials in elderly patients with cervical spondylotic myelopathy

BACKGROUND ： The recordings of evoked spinal cord potentials following epidural spinal cord stimulation are thought to be generated by volleys traversing the dorsal column pathway, and it may not directly reflect conduction defects in corticospinat tracts of cervical spinal cord. To our knowledge there has been few report using several evoked spinal cord potentials in function evaluation of the cervical spinal cord in eldedy patients with cervical spondylotic myelopathy （CSM）. OBJECTIVE： To investigate the function states of the cervical spinal cord in elderly patients with CSM and explore its pathophysictogic mechanism. DESIGN： Case observation SETTING ： Department of Orthopedics for the aged, Shenzhen Pingle Hospital of Orthopedics. Department of Orthopedic Surgery, Yamaguchi University School of Medicine. PARTICIPANTS ： A total of 23 eldedy patients with CSM who received treatment in the Department of Orthopedic Surgery, Yamaguchi University School of Medicine of Japan from January 2003 to February 2004 were enrolled in this study. Inclusive criteria： ① Multiple intervertebral levels of cervical spinal cord compression confirmed by MRI, e.g. 3 or more than 3 levels of compressin. ② Age ≥ 70 years old. ③ Numbness and sensory disturbance in the upper limbs and showed hyperreflexia in the lower limbs. Exclusive criteria： Patients with abnormal motor and sensory nerve conduction velocities in both upper and lower limbs were excluded. METHODS： Evoked spinal cord potentials （ESCPs） following transcranial electric stimulation （TCE-ESCPs）, epidural spinal cord stimulation （SpinaI-ESCPs） and median nerve stimulation （MN-ESCPs） were recorded in 23 patients from posterior epidural space intreoperatively. The abnormalities of TCE-ESCPs were defined as attenuation of amplitude of the D wave. The most cranial intervertebral level showing abnormal TCE-ESCPs with a marked reduction in size of the negative peak （reduction of over 50%） was considered as the upper level of the spinal cord lesion with respect to the corticospinal tract in white matter. The abnormalities of SpinaI-ESCPs were defined as marked reduction in the size of negative peak （reduction of over 50%）. The most caudal intervertebral level showing abnormal SpinaI-ESCPs was considered as the lower level of the spinal cord lesion with respect to the dorsal column pathway in white matter. The abnormalities of MN-ESCPs were defined as attenuation of the N13 amplitude,which was considered as the lesion level of the spinal cord with respect to the dorsal horn in gray matter. Radiological investigation： Lateral view of plain X-ray films was obtained in flexion and extension of the cervical spine. Instability of the cervical intervertebral level was determined as horizontal displacement of the vertebral body of over 3 mm. MAIN OUTCOME MEASURES ： The results of examination of TCE-ESCPs, SpinaI-ESCPs and MN-ESCPs in el- dedy patients with CSM. RESULTS： The 23 eldedy patients with CSM were participated in the result analysis. ①TCE-ESCPs： The impairment of the corticospinal tract in white matter at single intervertebral level was revealed in 18 of 23 patients by recordings of TCE-ESCPs （sensitivity 78%）. In the 18 patients, the lesion level was shown at the up- per cervical segment in 14 patients （C3-4n=10 and C4-5n=4）, and at the lower cervical segment in 4 patients （C5-6n=4）. ②Spinal-ESCPs： The impairment of the dorsal column pathway of white matter at single intervertebral level was revealed in 17 of 23 patients, by recordings of Spinal-ESCPs （sensitivity 74%）. In the 17 patients, the lesion level was presented at the upper cervical segment in 14 patients （C3-4n=10 and C4-5n=4）, and at the lower cervical segment in 3 patients （C5-6 n=3）. ③MN-ESCPs： All patients revealed abnormal MN-ESCPs at one or more intervertebral levels （sensitivity 100%）. The impairment at single intervertebral level was demonstrated in 17 patients, and the impairment at multiple intervertebral levels was shown in 4 patients （3 patients at the C3-4, C4-4, and C5-4~6, and one patient at the C4-5, C5-6, and C6-7）. ④Radiological findings： The Instability of the intervertebral level at the C3-4 or C4-5 motion segment was seen in 15 patients, with a total of 20 levels, and where 10 were at the C3-4 intervertebral level and 5 were at the C3-4, C4-5 intervertebral level. CONCLUSION ： The results suggest that in most elderly patients with CSM who have multiple intervertebral level compressions of the cervical spinal cord on MRI, white matter is impaired at the single cervical intervertebral level, and not only the dorsal column pathway, but also the corticospinal tract can be affected. Combined the findings of radiography, the excessive motion and instability of the C3-4 or C4-5 intervertebral level plays an important role in inducing the long tract lesion in elderly patients with CSM.

A novel mouse model of central cord syndrome

Patients with potential spinal stenosis are susceptible to central cord syndrome induced by blunt trauma.Suitable animal models are helpful for studying the pathogenesis and treatment of such injuries.In this study,we established a mouse model of acute blunt traumatic spinal cord injury by compressing the C6 spinal cord with 5 and 10 g/mm~2 compression weights to simulate cervical central cord syndrome.Behavioral testing confirmed that this model exhibited the characteristics of central cord syndrome because motor function in the front paws was impaired,whereas basic motor and sensory functions of the lower extremities were retained.Hematoxylin-eosin staining showed that the diseased region of the spinal cord in this mouse model was restricted to the gray matter of the central cord,whereas the white matter was rarely affected.Magnetic resonance imaging showed a hypointense signal in the lesion after mild and severe injury.In addition,immunofluorescence staining showed that the degree of nerve tract injury in the spinal cord white matter was mild,and that there was a chronic inflammation reaction.These findings suggest that this mouse model of central cord syndrome can be used as a model for preclinical research,and that gray matter is most vulnerable to injury in central cord syndrome,leading to impaired motor function.

Does diffusion tensor data reflect pathological changes in the spinal cord with chronic injury?

Magnetic resonance diffusion tensor imaging has been shown to quantitatively measure the early pathological changes in chronic cervical spondylotic myelopathy. In this study, a novel spongy poly- urethane material was implanted in the rat C^-s epidural space to establish a rat model of chronic cervical spondylotic myelopathy. Diffusion tensor data were used to predict pathological changes. Results revealed that the fractional anisotropy value gradually decreased at 4, 24, and 72 hours and 1 week after injury in rat spinal cord, showing a time-dependent manner. Average diffusion coeffi- cient increased at 72 hours and 1 week after implantation. Hematoxylin-eosin staining and Luxol-fast-blue staining exhibited that the number of neurons in the anterior horn of the spinal cord gray matter and the nerve fiber density of the white matter gradually reduced with prolonged com- pression time. Neuronal loss was most significant at 1 week after injury. Results verified that the fractional anisotropy value and average diffusion coefficient reflected the degree of pathological change in the site of compression in rat models at various time points after chronic spinal cord compression injury, which potentially has a reference value in the early diagnosis of chronic cervical spondylotic myelopathy.

Diffusion tensor imaging of spinal microstructure in healthy adults： improved resolution with the readout segmentation of long variable echo-trains

Diffusion tensor imaging plays an important role in the accurate diagnosis and prognosis of spinal cord diseases. However, because of technical limitations, the imaging sequences used in this technique cannot reveal the fine structure of the spinal cord with precision. We used the readout segmentation of long variable echo-trains（RESOLVE） sequence in this cross-sectional study of 45 healthy volunteers aged 20 to 63 years. We found that the RESOLVE sequence significantly increased the resolution of the diffusion images and improved the median signal-to-noise ratio of the middle（C4–6） and lower（C7–T1） cervical segments to the level of the upper cervical segment. In addition, the values of fractional anisotropy and radial diffusivity were significantly higher in white matter than in gray matter. Our study verified that the RESOLVE sequence could improve resolution of diffusion tensor imaging in clinical applications and provide accurate baseline data for the diagnosis and treatment of cervical spinal cord diseases.

Subarachnoid disseminative hemangiopericytoma of the spinal cord

Hemangiopericytomas （HPCs） originating from central nervous system were increasingly reportedrecently. Intravertebral HPCs are preclomlnanuy eplaural. Primary intradural HPCs of spinal cord are rare. Little subarachnoid dissemination has been reported. We reported a HPC of the cervical spinal cord with subarachnoid dissemination.