Spinal Anesthesia with Targeted Sedation based on Bispectral Index Values Compared with General Anesthesia with Masked Bispectral Index Values to Reduce Delirium: The SHARP Randomized Controlled Trial.

BACKGROUND: Reducing depth of anesthesia and anesthetic exposure may help prevent delirium, but trials have been conflicting. Most studies were conducted under general anesthesia or in cognitively impaired patients. It is unclear whether reducing depth of anesthesia beyond levels consistent with general anesthesia reduces delirium in cognitively intact patients. The authors' objective was to determine whether a bundled approach to reduce anesthetic agent exposure as determined by Bispectral Index (BIS) values (spinal anesthesia with targeted sedation based on BIS values) compared with general anesthesia (masked BIS) reduces delirium. METHODS: Important eligibility criteria for this parallel-arm randomized trial were patients 65 yr or greater undergoing lumbar spine fusion. The intervention group received spinal anesthesia with targeted sedation to BIS greater than 60 to 70. The control group received general anesthesia (masked BIS). The primary outcome was delirium using the Confusion Assessment Method daily through postoperative day 3, with blinded assessment. RESULTS: The median age of 217 patients in the analysis was 72 (interquartile range, 69 to 77). The median BIS value in the spinal anesthesia with targeted sedation based on BIS values group was 62 (interquartile range, 53 to 70) and in the general anesthesia with masked BIS values group was 45 (interquartile range, 41 to 50; P < 0.001). Incident delirium was not different in the spinal anesthesia with targeted sedation based on BIS values group (25.2% [28 of 111] vs. the general anesthesia with masked BIS values group (18.9% [20 of 106]; P = 0.259; relative risk, 1.22 [95% CI, 0.85 to 1.76]). In prespecified subgroup analyses, the effect of anesthetic strategy differed according to the Mini-Mental State Examination, but not the Charlson Comorbidity Index or age. Two strokes occurred among patients receiving spinal anesthesia and one death among patients receiving general anesthesia. CONCLUSIONS: Spinal anesthesia with targeted sedation based on BIS values compared with general anesthesia with masked BIS values did not reduce delirium after lumbar fusion.

Spinal Anesthesia for Geriatric Lumbar Spine Surgery: A Comparative Case Series.

BACKGROUND: The use of spinal anesthesia (SA) as opposed to general anesthesia (GA) during elective lumbar spine surgery is an emerging technique and represents a potentially modifiable factor to limit perioperative complications. Few studies, however, have compared these anesthetic techniques in an elderly population. The aim of this study is to determine if SA is a safe alternative to GA for lumbar spine surgery in elderly patients. METHODS: A retrospective, consecutive case series study was performed. All patients aged 70 years and older who underwent lumbar spine decompression or combined decompression and fusion using either SA or GA during a 2-year period at a single institution were identified. Demographics and perioperative outcomes were compared. RESULTS: Of all patients meeting the inclusion criteria, 56 patients (19%) received SA and 239 (81%) received GA. Patients receiving SA were slightly older (median age, 77 years versus 75 years, P = .002), consisted of more men (57% versus 36%, P = .01), and had a lower mean body mass index (28.3 versus 30.1, P = .03). Indications for surgery and type of surgery were similar between groups. On average, operative times with SA were 101 minutes versus 103 minutes with GA (P = .71). After controlling for age, sex, and body mass index, patients receiving SA had decreased estimated blood loss (ß = -75 mL; 95% confidence interval [CI], -140.6, -9.4; P = .025) and intraoperative intravenous fluid requirements (ß = -205 mL; 95% CI, -389.4, -21.0; P = .029), shorter postanesthesia care unit stays (ß = -41 minutes; 95% CI, -64.6, -16.9; P = .001), lower maximum visual analog scale pain scores (ß = -0.89 points; 95% CI, -1.6, -0.1; P = .020), and decreased odds of receiving blood transfusion (odds ratio, 0.12; 95% CI, 0.01, 0.62; P = .45); there were no significant differences in operative time, length of stay, nausea, or oral morphine equivalents consumed per day. Complication rates were similar between groups. CONCLUSION: Spinal anesthesia is a reasonable, safe alternative to general anesthesia for lumbar spine surgery in elderly patients with degenerative conditions.

Shaping anesthetic techniques to reduce post-operative delirium (SHARP) study: a protocol for a prospective pragmatic randomized controlled trial to evaluate spinal anesthesia with targeted sedation compared with general anesthesia in older adults undergoing lumbar spine fusion surgery.

BACKGROUND: Postoperative delirium is common in older adults, especially in those patients undergoing spine surgery, in whom it is estimated to occur in > 30% of patients. Although previously thought to be transient, it is now recognized that delirium is associated with both short- and long-term complications. Optimizing the depth of anesthesia may represent a modifiable strategy for delirium prevention. However, previous studies have generally not focused on reducing the depth of anesthesia beyond levels consistent with general anesthesia. Additionally, the results of prior studies have been conflicting. The primary aim of this study is to determine whether reduced depth of anesthesia using spinal anesthesia reduces the incidence of delirium after lumbar fusion surgery compared with general anesthesia. METHODS: This single-center randomized controlled trial is enrolling 218 older adults undergoing lumbar fusion surgery. Patients are randomized to reduced depth of anesthesia in the context of spinal anesthesia with targeted sedation using processed electroencephalogram monitoring versus general anesthesia without processed electroencephalogram monitoring. All patients are evaluated for delirium using the Confusion Assessment Method for 3 days after surgery or until discharge and undergo assessments of cognition, function, health-related quality of life, and pain at 3- and 12-months after surgery. The primary outcome is any occurrence of delirium. The main secondary outcome is change in the Mini-Mental Status Examination (or telephone equivalent) at 3-months after surgery. DISCUSSION: Delirium is an important complication after surgery in older adults. The results of this study will examine whether reduced depth of anesthesia using spinal anesthesia with targeted depth of sedation represents a modifiable intervention to reduce the incidence of delirium and other long-term outcomes. The results of this study will be presented at national meetings and published in peer-reviewed journals with the goal of improving perioperative outcomes for older adults. TRIAL REGISTRATION: Clinicaltrials.gov , NCT03133845. This study was submitted to Clinicaltrials.gov on October 23, 2015; however, it was not formally registered until April 28, 2017 due to formatting requirements from the registry, so the formal registration is retrospective.

Spinal Anesthesia in Elderly Patients Undergoing Lumbar Spine Surgery.

Spinal anesthesia is increasingly viewed as a reasonable alternative to general anesthesia for lumbar spine surgery. However, the results of spinal anesthesia in elderly patients undergoing lumbar spine decompression and combined decompression and fusion procedures are limited in the literature. The aim of this study was to report a single institution's experience using spinal anesthesia in elderly patients undergoing lumbar spine surgery. A retrospective review was conducted using a prospectively collected database of consecutive lumbar spine surgeries performed under spinal anesthesia in patients 70 years or older at a single center between December 2013 and October 2015. A total of 56 patients were included in the study; 27 patients (48%) underwent lumbar decompression and 29 patients (52%) underwent combined decompression and fusion procedures. Mean operative time was 101 minutes (range, 30-210 minutes), and mean operative blood loss was 187 mL (range, 20-700 mL). Mean maximum inpatient postoperative visual analog scale score was 6.2 (range, 1-10). Nausea occurred in 21% (12 of 56) of the patients. Mean length of stay was 2.4 days (range, 1-6 days). No mortality, stroke, permanent loss of function, or pulmonary embolism occurred. None of the cases required conversion to general anesthesia. All of the patients were ambulatory on either the day of the surgery or the next morning. These results demonstrate that spinal anesthesia is a viable method of anesthesia for patients 70 years and older undergoing lumbar spine surgery. They also demonstrate the safety of this method for patients older than 84 years and for surgeries lasting up to 3½ hours. [Orthopedics. 2017; 40(2):e317-e322.].

Degenerative spondylolisthesis of the cervical spine: analysis of 58 patients treated with anterior cervical decompression and fusion.

BACKGROUND CONTEXT: Degenerative spondylolisthesis has been well described as a disorder of the lumbar spine. Few authors have suggested that a similar disorder occurs in the cervical spine. To our knowledge, the present study represents the largest series of patients with long-term follow-up who were managed surgically for the treatment of degenerative spondylolisthesis of the cervical spine. PURPOSE: To describe the clinical presentation and radiographic findings associated with degenerative cervical spondylolisthesis, and to report the long-term results of surgically managed patients. STUDY DESIGN: Analysis of 58 patients treated with anterior cervical decompression and fusion for degenerative spondylolisthesis of the cervical spine. PATIENT SAMPLE: From 1974 to 2003, 58 patients were identified as having degenerative spondylolisthesis of the cervical spine occurring in the absence of trauma, systemic inflammatory arthropathy, or congenital abnormality. These patients were identified from a database of approximately 500 patients with degenerative cervical spine disorders treated by the senior one of us. OUTCOME MEASURES: Patient outcomes were evaluated with regard to neurologic improvement (Nurick grade myelopathy) and osseous fusion. METHODS: The records of 58 patients were reviewed. The average follow-up period was 6.9 years (range, 2-24 years). Seventy-two cervical levels demonstrated spondylolisthesis. In all cases, there was radiographic evidence of facet degeneration and subluxation. All patients were treated with anterior cervical decompression and arthrodesis with iliac crest structural graft. This most commonly involved corpectomy of the caudal vertebrae. Three patients required additional posterior facet fusion. RESULTS: Fifty-eight patients demonstrated 72 levels of involvement. The C4-C5 level was most frequently involved (43%). Two radiographically distinct types of listhesis were observed based on the amount of disc degeneration and the degree of spondylosis at adjacent levels. The average neurologic improvement was 1.5 Nurick grades. The overall fusion rate was 92%. Three patients were treated with combined anterior-posterior arthrodesis. The prevalence of myelopathy and instability pattern was greater in the listheses occurring adjacent to spondylotic levels. CONCLUSIONS: Degenerative spondylolisthesis is relatively common in the cervical spine. Common to all cases is facet arthropathy and neurologic compression. Anterior cervical decompression and arthrodesis appears to yield excellent union rates and neurological improvement in those patients having cervical degenerative spondylolisthesis and significant neurological sequelae who have failed nonoperative treatments.

Correlation between computed tomography measurements and direct anatomic measurements of the axis for consideration of C2 laminar screw placement.

BACKGROUND: C2 laminar screws are becoming an increasingly used method of fixation. They allow for avoidance of fixation through the C2 pedicle, eliminating the risk of vertebral artery injury. Recent studies have described the anatomic considerations of this technique in a large cadaveric population. In clinical practice, however, direct measurement is impractical and preoperative imaging must be relied upon to determine whether or not this technique can be safely used. PURPOSE: To evaluate the ability of computed tomography (CT) to accurately assess critical dimensions of the C2 vertebrae with regard to intralaminar screw placement. STUDY DESIGN/SETTING: Cadaveric analysis. METHODS: The C2 vertebrae of 84 adult spines were randomly selected from a large cadaveric collection. Direct measurements were performed to determine laminar thickness, estimated screw length, and spinolaminar angle. Fine cut axial CT scans were then performed on all specimens and all measurements were repeated from these images. Correlation coefficients were calculated to determine the ability of CT scan to accurately determine these measurements. RESULTS: CT scan measurements were found to be highly correlated with direct measurements for both left and right mean laminar thickness (0.975 and 0.947, respectively). Screw lengths using CT scan were found to be significantly longer than previously reported direct measurements (24.8 vs. 28.8mm; p<.01). The mean CT spinolaminar angle was 42.45 degrees, whereas it was 48.47 degrees on direct measurement. Correlation coefficient for spinolaminar angle measurements was low (0.23); however, this is likely because of measurement variability. CONCLUSIONS: Given the high degree of correlation between CT measurements and direct anatomic measurements, we conclude that CT scan can accurately determine laminar thickness, a measurement critical to safe placement of intralaminar screws. It appears that longer screw lengths that were previously reported may be safely used while remaining intra-osseous. We continue to advocate preoperative planning using CT to identify patients whose lamina may be unable to accommodate safe screw placement using this technique.

Reherniation and failure after lumbar discectomy: a comparison of fragment excision alone versus subtotal discectomy.

STUDY DESIGN: Retrospective review of 259 lumbar discectomies. OBJECTIVE: To compare rates of reoperation after subtotal discectomy versus established rates after fragment excision. SUMMARY OF BACKGROUND DATA: Herniated nucleus pulposes (HNP) and annular morphology influence rates of reherniation after discectomy. Certain patterns are linked to reherniation rates exceeding 20%. METHODS: We retrospectively reviewed 259 single-level lumbar discectomies performed between 1980 and 2005. Mean follow-up was 60.9 months. In each case, annulotomy and subtotal discectomy was performed in addition to excision of disc fragments. HNP morphology was classified according to the 4-part system of Carragee (type 1: fragment/fissure; type 2: fragment/defect; type 3: fragment/contained; type 4: no fragment/contained). Fisher exact test was used to compare our proportion of patients with reherniation and/or reoperation to Caragee's series in which only fragment excision was performed. RESULTS: Of 259 cases, 12 (4.5%) reoperations were performed. A significant difference in failure/reoperation rate was noted in type 2 herniations. There was a significantly lower rate of failure and reoperation for type 2 HNP after subtotal discectomy (3.4%) when compared with fragment excision alone (21.2%), P<0.003. CONCLUSIONS: Subtotal discectomy is an acceptable technique that decreases reherniation after lumbar discectomy.

Ketorolac use for postoperative pain management following lumbar decompression surgery: a prospective, randomized, double-blinded, placebo-controlled trial.

STUDY DESIGN: Prospective randomized double-blind placebo-controlled study. OBJECTIVE: The objective of this study was to assess the efficacy of Ketorolac in reducing postoperative pain and morphine requirements following primary multilevel lumbar decompression surgery. SUMMARY OF BACKGROUND DATA: The use of opioid medications following surgical interventions can be complicated by related side effects such as respiratory depression, somnolence, urinary retention, and delayed time to oral intake. The use of Ketorolac, a potent nonopioid, nonsteroidal anti-inflammatory drug, is an attractive alternative to morphine as many of the opioid-related side effects can be avoided. METHODS: After Institutional Review Board approval, 25 patients who underwent a primary multilevel lumbar decompression procedure were randomly assigned to receive either Ketorolac or placebo in a double-blinded fashion. After surgery, all patients were allowed to receive intravenous morphine on an as needed basis. Morphine requirements were then recorded immediately postoperative, at 6, 12, and at 24 hours postoperative. A patient's overall hospital course morphine requirement was also assessed. Patient postoperative pain levels were determined using the Visual Analog Pain Scale and were documented at 4, 8, 12, 16, 24, and 36 hours postoperative. RESULTS: There were no significant differences in available patient demographics, intraoperative blood loss, or postoperative Hemovac drain output between study groups. Morphine equivalent requirements were significantly less at all predetermined time points in addition to the overall hospital morphine requirement in patients randomized to receive Ketorolac. Visual Analog Pain Scores were significantly lower in patients randomized to receive Ketorolac immediately postoperative in addition to 4, 12, and 16 hours postoperative. There were no identifiable postoperative complications associated with the use of Ketorolac. CONCLUSION.: Intravenous Ketorolac seems to be a safe and effective analgesic agent following multilevel lumbar decompressive laminectomy. Patients can expect lower morphine requirements and better pain scores throughout their postoperative course.

Cauda equina syndrome resulting from treatment of dural ectasia with fibrin glue injection.

The use of fibrin glue injection to treat symptomatic dural ectasia is controversial. A case of cauda equina syndrome following percutaneous fibrin glue injection is presented, followed by a review of dural ectasia and its possible treatments.