Sharp systolic blood pressure elevation at extubation is a risk factor for symptomatic epidural hematoma after spine surgery.

STUDY DESIGN: The present study is a single-center retrospective cohort study. OBJECTIVE: The objective of the study is to verify the hypothesis that sharp elevation of systolic blood pressure at extubation is a risk factor for development of symptomatic epidural hematoma after spinal surgery. SUMMARY OF BACKGROUND DATA: Postoperative symptomatic epidural hematoma (she) after spine surgery is a rare but potentially serious complication that may result in paralysis unless removed at an early stage. METHODS: The subjects were 2611 patients treated with decompression and decompression/fusion of the cervical, thoracic, and lumbar vertebrae at our hospital. Twelve of these patients developed postoperative SEH and removal of hematoma was performed. To investigate the risk factors in these patients, data were analyzed for age at the time of surgery, sex, preoperative complications, medical history, body mass index, preoperative platelet count, surgical procedure, microscope use, operative time, blood loss, surgical site, systolic blood pressure (SBP) at extubation, difference between resting and extubation SBP, ratio of SBP at extubation to that at rest, blood pressure at discharge from the operating room, and use of a drain. RESULTS: There was a significantly higher rate of SBP ratio (extubation/rest) ≥1.3 in patients with SEH (p = 0.021, Fisher's exact test). Among the preoperative complications and medical histories, the frequency of cerebrovascular disorder tended to be higher in SEH cases than in non-SEH cases (p = 0.073). There was no significant difference for all other parameters listed above. In multivariate logistic analysis, the odds ratios were 3.98 (p = 0.018) for an SBP ratio (extubation/rest) ≥1.3 and 4.75 (p = 0.055) for cerebrovascular disorder, suggesting effects of these two items. With simultaneous input into a multivariate model, SBP ratio ≥1.3 had a significant independent association with postoperative SEH (p = 0.021) and cerebrovascular disorder showed a tendency for this association (p = 0.072). CONCLUSION: The risk for symptomatic epidural hematoma is significant in patients with SBP at extubation that is more than 1.3 times that of SBP at rest.

A Case of Spontaneous Spinal Subdural Hematoma Complicated by Cranial Subarachnoid Hemorrhage and Spinal Adhesive Arachnoiditis.

A 76-year-old woman with a spinal subdural hematoma (SDH) was presented with severe back pain without headache. Magnetic resonance imaging (MRI) performed 4 days after onset showed SDH extending from Th2 to L3. She was diagnosed with spontaneous SDH without neurological manifestation, and conservative treatment was selected. Transient disturbance of orientation appeared 7 days after onset. Small subarachnoid hemorrhage (SAH) was detected on head CT, and strict antihypertensive therapy was started. Symptoms changed for the better. Back pain disappeared 4 weeks after onset. On follow-up MRI at 6 months after onset, the SDH had been resolved spontaneously. Although adhesive arachnoiditis was observed at Th4-6, the recurrence of clinical symptoms was not observed at one year and a half after onset. Spinal subdural space is almost avascular; a hematoma in a subdural space is considered to come from a subarachnoid space when it is a lot. A hemorrhage in subarachnoid space was flushed by cerebral spinal fluid; hematoma or arachnoiditis was not formed in general. In our case, hemorrhage was a lot and expansion of SDH was large enough to cause cranial SAH and arachnoiditis. But longitudinally expanded SDH did not show neurological manifestation and resolved spontaneously in our case.

Use of intrawound vancomycin powder against postoperative infection after spine surgery.

Local application of vancomycin has recently become widely used in spine surgery. However, local application is not included in the indication and has not been approved by the US Food and Drug Administration (FDA). Thus, we searched for reports with "intra wound-vancomycin" and "SSI" as keywords in the MEDLINE database, and investigated the efficacy, problems with use, and future prospects based on these reports. Intrawound vancomycin was described as effective in most of the reports, but was found to have no effect or to aggravate the condition in some reports. A toxic effect on osteoblasts due to a high local concentration was described in some reports, whereas local application was found to be safe in other studies. The amount of vancomycin used and the administration method varied among the reports. Overall, the results suggest that intrawound vancomycin is clinically effective, but this has yet to be established in a randomized controlled trial. There is a need to identify cases that should be selected for this treatment and to investigate the dose and optimum concentration of vancomycin for clinical use.

Solitary Spinal Epidural Metastasis from Gastric Cancer.

Solitary epidural space metastasis of a malignant tumor is rare. We encountered a 79-year-old male patient with solitary metastatic epidural tumor who developed paraplegia and dysuria. The patient had undergone total gastrectomy for gastric cancer followed by chemotherapy 8 months priorly. The whole body was examined for suspected metastatic spinal tumor, but no metastases of the spine or important organs were observed, and a solitary mass was present in the thoracic spinal epidural space. The mass was excised for diagnosis and treatment and was histopathologically diagnosed as metastasis from gastric cancer. No solitary metastatic epidural tumor from gastric cancer has been reported in English. Among the Japanese, 3 cases have been reported, in which the outcome was poor in all cases and no definite diagnosis could be made before surgery in any case. Our patient developed concomitant pneumonia after surgery and died shortly after the surgery. When a patient has a past medical history of malignant tumor, the possibility of a solitary metastatic tumor in the epidural space should be considered.

Evaluation of antimicrobial prophylaxis against postoperative infection after spine surgery: Limit of the first generation cephem.

In our department, first-generation cephem (CEZ) are generally administered for 2 days as antimicrobial prophylaxis (AMP) for spinal surgery. However, the incidence of surgical site infection (SSI) has recently increased, particularly cases involving coagulase-negative Staphylococci (CNS) as an etiologic agent. The objective was to elucidate the problems with the current AMP and the risk factors of SSI through a retrospective investigation of affected cases. The subjects were patients who underwent spine surgery at our department between August 2007 and June 2013. The subjects were divided into those who developed SSI (S group) and who did not develop SSI (non-SSI (N) group), patients who developed CNS infection in the S group was subdivided as C group, and the risk factors were investigated. The significance of each factor was analyzed using cross tabulation, and multivariate logistic regression analyses were performed with 22 of the investigation factors as explanatory variables. The incidence of SSI was 2.55%, and the etiologic agent was CNS in 17 patients. Upon comparison between the S and N groups, the presence of 3 or more underlying diseases and blood loss were extracted as significant risk factors. Upon comparison between the C and N groups, emergency surgery and intra- and postoperative steroid administration were extracted as significant risk factors, in addition to the presence of 3 or more underlying diseases and blood loss. The effect of the current AMP using first generation cephem is limited, and reconsideration of the protocol may be necessary.

Comparison of the invasiveness of conventional discectomy and microendoscopic discectomy for lumbar disc herniation: Differences in the methods of approach.

INTRODUCTION: The aim of this study was to investigate whether differences in the methods of approach to the vertebral arch influence the invasiveness of conventional discectomy and microendoscopic discectomy (MED). METHODS: In this study, 41 Wistar rats were divided into four groups: controls (no surgery) (n = 10), shams (skin incision only) (n = 11), MED (n = 10), and conventional discectomy (n = 10). We performed ethological and blood biochemical examinations for three of the groups, excluding the control group, and a histological examination for three of the groups, excluding the sham group. In the ethological examination, we measured the threshold of postoperative pain using the von Frey test. In the blood chemical examination, we measured blood creatine phosphokinase and inflammatory cytokines, and compared the severity of tissue damage by histological examination using hematoxylin-eosin and immunohistochemical staining. RESULTS: The conventional discectomy group showed a significantly lower threshold of postoperative pain, compared with the MED group (P < 0.05). Blood biochemical investigation revealed that the creatine phosphokinase (P < 0.05) and tumor necrosis factor-α levels (P < 0.05) of the conventional discectomy group were significantly higher than those in the MED group. In the histological examination, it was found that a wide range of paraspinal muscle damage occurred in the conventional discectomy group (P < 0.05) and that the damage was mostly confined to the periosteum and nearby nerve endings. CONCLUSION: MED was found to be less invasive than conventional discectomy based on ethological, blood biochemical, and histological examinations.

Spontaneous symptomatic pseudoarthrosis at the l2-l3 intervertebral space with diffuse idiopathic skeletal hyperostosis: a case report.

Pseudoarthrosis at the intervertebral space in patients with ankylosing spondylitis has occasionally been reported, but symptomatic pseudoarthrosis at the intervertebral disc level is rare in patients with diffuse idiopathic skeletal hyperostosis (DISH). Here, we report a case of symptomatic pseudoarthrosis at the L2-L3 intervertebral space that was diagnosed based on clinical history. We first performed L1-L5 fixation, but back-out of the pedicle screw occurred in the early postoperative phase and may have been caused by a short fixation range and concomitant Parkinson's disease. However, the prognosis of the case was favorable after a second surgery. This case indicates that a fixation range of at least 3 above and 3 below is necessary for bone fracture of a thoracolumbar vertebra and pseudoarthrosis in patients with DISH.

Treatment of Renal Cell Carcinoma with 2-Stage Total en bloc Spondylectomy after Marked Response to Molecular Target Drugs.

Metastatic renal cell carcinoma of the bone occurs at a high rate, and the prognosis is poor. In general, total en bloc spondylectomy is considered when there is only one vertebral metastasis and the primary disease is treated. However, palliative surgery is selected when the primary disease is not being treated or metastasis occurs to an important organ. We encountered a patient in whom lung and vertebra metastases were already present at the time of the first examination at our department and the prognosis was considered poor. However, molecular targeted therapy was markedly effective and enabled 2-stage total en bloc spondylectomy. As of one year after total en bloc spondylectomy, the condition has improved to cane gait, and surgery for lung metastasis is planned. Molecular target drugs might markedly change the current therapeutic strategy for renal cell carcinoma.

Incidence of venous thromboembolism after spine surgery.

BACKGROUND: The incidence of venous thromboembolism (VTE) has varied among studies of patients undergoing elective spine surgery. This may be because of differences in prophylaxis for VTE and differences in methods of observation. Furthermore, some studies have reported symptomatic deep vein thrombosis (DVT) or pulmonary thromboembolism (PE), whereas others have included asymptomatic DVT or PE, making comparisons difficult. Therefore, the objective of this study was to determine the incidence of symptomatic and asymptomatic PE in patients undergoing elective spine surgery and to evaluate therapeutic methods for these conditions. METHODS: The subjects were 1975 patients who underwent spine surgery in our hospital from 1990 to 2011. Patients treated from January 1990 to November 1996 (n = 541, Group A) did not receive prophylaxis whereas those treated from January 2000 to February 2011 (n = 1,434, Group B) used a foot pump during and after surgery and subsequently wore elastic stockings. All subjects in Group A began ambulation ≥2 weeks after surgery whereas those in Group B began to walk earlier-within 3 days for patients who underwent decompression and within 1 week for those treated with fusion. From June 2010 to February 2011, contrast-enhanced computed tomography (CT) was performed 1 week after surgery for 100 patients to evaluate the presence of DVT and PE. Since March 2004, D-dimer was measured 1 week after surgery and patients with a level ≥10 µg/mL were followed up. RESULTS: The incidence of symptomatic PE was significantly higher in Group A than in Group B (8/541, 1.5% vs. 3/1,434, 0.2%). In 3 patients in Group B, PE developed within 1 week postoperatively and D-dimer values at onset were ≤10 µg/mL. In the 100 cases examined by contrast-enhanced computed tomography (CT), asymptomatic PE and VTE were detected in 18 and 19%, respectively. The D-dimer level 1 week after surgery was ≥10 µg/mL in 105 of 841 patients; however, none of these patients had clinically symptomatic VTE for at least 3 months postoperatively. CONCLUSIONS: Mechanical prophylaxis and early ambulation may be effective in reducing the incidence of symptomatic PE after spine surgery. Asymptomatic PE developed in 18% of patients who received mechanical prophylaxis, but the incidence of symptomatic PE was only 0.2%. Prompt diagnosis and treatment are required for patients who develop symptomatic PE.

Effect of cage geometry on sagittal alignment after posterior lumbar interbody fusion for degenerative disc disease.

PURPOSE: To compare the sagittal alignment of the lumbar spine after one-segment posterior lumbar interbody fusion (PLIF) using the horizontal cylinder (HC) or open box (OB) type cage. METHODS: 66 patients underwent instrumented one-segment PLIF with bone grafting for lower lumbar degenerative disease. HC-type cages were used in 33 men and 13 women aged 20 to 73 (mean, 47) years between September 2001 and July 2004. OB-type cages with a 3-degree lordotic angle were used in 9 men and 11 women aged 25 to 70 (mean, 53) years between July 2004 and September 2006. Pre- and post-operative lumbar lordosis and intervertebral body angles in the fused and upper adjacent levels in the 2 groups were compared. RESULTS: There was no significant difference between the 2 groups with regard to changes in the lumbar lordosis and intervertebral body angle in the fused and upper adjacent levels. In both groups, the upper adjacent intervertebral body angle increased significantly by about 2 degrees. CONCLUSION: Lumbar alignment was similar after the use of the HC- or OB-type cages. This may be due to the surgical procedure and insufficient cage lordotic angle.

Antimicrobial prophylaxis for spinal surgery.

BACKGROUND: The concept of antimicrobial prophylaxis (AMP) did not exist in Japan until recently. Therefore, postoperative administration of antimicrobial drugs has long been practiced under the pretext of prophylaxis against surgical site infection (SSI). In recent years, however, the concept of AMP and prophylactic countermeasures against SSI, based on evidence of the effectiveness of AMP, has gradually spread in Japan. From 2000 onward, we have undertaken prophylactic countermeasures against SSI in patients undergoing spinal surgery referring to the Guideline for Prevention of Surgical Site Infection published by the Centers for Disease Control and Prevention in 1999. The purpose of this study was to investigate the type of AMP that would be appropriate for spinal surgery and the manner in which it should be used. METHODS: The subjects were 1415 patients who underwent spinal surgery at our department from January 1990 to March 2008. The patients were classified into four groups according to the method of AMP administration: group 1, AMP was employed for 7 days, only postoperatively; group 2, initial AMP dosing was administered at the time of anesthesia induction, followed by administration of AMP for 5 days, including the day of the operation; group 3, initial AMP dosing was administered at the time of anesthesia induction, and AMP was administered for 3 days, including the day of the operation; group 4, the initial dosing was administered at the time of anesthesia induction, and AMP was administered for 2 days, including the day of the operation. The frequency of SSI was assessed in the four groups. RESULTS: The frequencies of SSI in groups 1-4 were 2.6% (14/539), 0.9% (5/536), 0% (0/257), and 0% (0/83), respectively. Thus, the frequency of SSI decreased as the duration of the AMP administration period decreased. CONCLUSIONS: As a result of thorough implementation of preventive measures against perioperative occurrence of infections, which included additional preoperative and intraoperative administration of AMP, the incidence of SSI could be decreased despite shortening the duration of AMP administration to 2 days.

Modification of halogen specificity of a vanadium-dependent bromoperoxidase.

The halide specificity of vanadium-dependent bromoperoxidase (BPO) from the marine algae, Corallina pilulifera, has been changed by a single amino acid substitution. The residue R397 has been substituted by the other 19 amino acids. The mutant enzymes R397W and R397F showed significant chloroperoxidase (CPO) activity as well as BPO activity. These mutant enzymes were purified and their properties were investigated. The maximal velocities of CPO activities of the R397W and R397F enzymes were 31.2 and 39.2 units/mg, and the K(m) values for Cl(-) were 780 mM and 670 mM, respectively. Unlike the native enzyme, both mutant enzymes were inhibited by NaN(3). In the case of the R397W enzyme, the incorporation rate of vanadate into the active site was low, compared with the R397F and the wild-type enzyme. These results supported the existence of a specific halogen binding site within the catalytic cleft of vanadium haloperoxidases.