Puffer, Ross C.

Abstract BACKGROUND: Patients with pleomorphic xanthoastrocytoma (PXA) routinely undergo multiple procedures to ensure recurrence-free survival and are resultantly at increased risk of experiencing perioperative complications (regional, medical, and/or neurological), a combination of which has not been recorded in previous studies. OBJECTIVE: To determine perioperative outcomes in a cohort of patients (adult and pediatric) with intracranial PXA. METHODS: We retrospectively identified 39 patients who underwent surgery at our institution for intracranial PXA between 1994 and 2011. Demographic factors were recorded along with Karnofsky Performance Status (KPS), complications, and mortality. RESULTS: Mean patient age was 31 years at the most recent surgery. A majority of patients (24; 62%) had multiple surgeries with a mean of 2 operations per patient. Eleven PXAs (28%) were malignant (grade III or IV). Perioperative complications included permanent neurological worsening in 4 patients (10%), regional complications in 4 (10%), and medical complications in 3 (8%). Preoperative KPS was ≥70 in 34 of 38 patients (89%). Long-term postoperative KPS was ≥70 in 36 of 37 patients (97%), suggesting good functional outcomes. There was no perioperative mortality, but 7 patients (18%) died of tumor progression. Patients with malignant PXAs trended toward higher risk of regional complications (3 of 11 patients [27%]; P = .06), received adjuvant therapy more often (10 of 11 patients [91%]; P < .001), had higher mortality from tumor progression (7 of 11 patients [64%]; P < .001), and were significantly larger (mean, 6.05 ± 0.73 cm standard error of the mean; n = 7; P < .01). CONCLUSION: Both pediatric and adult PXAs may be resected with good functional outcomes. Perioperative neurological complications are relatively common, but do not affect long-term functional outcome or mortality. Malignant PXAs are higher risk for perioperative complications and, ultimately, death from tumor progression, despite increased use of adjuvant radiation and chemotherapy.

Study Design Retrospective study. Objective This study reviews 1,768 consecutive cervical decompressions with or without instrumented fusion to identify patient-specific and procedural risk factors significantly correlated with the development of delayed cervical palsy (DCP). Methods Baseline demographic and procedural information was collected from the electronic medical record. Particular attention was devoted to reviewing each chart for recognized risk factors of postsurgical inflammatory neuropathy: autoimmune disease, blood transfusions, diabetes, and smoking. Results Of 1,669 patients, 56 (3.4%) developed a DCP. Although 71% of the palsies involved C5, 55% of palsies were multimyotomal and 18% were bilateral. Significant risk factors on univariate analysis included age ( p = 0.0061, odds ratio [OR] = 1.07, 95% confidence interval [CI] 1.008 to 1.050), posterior instrumented fusion ( p < 0.0001, OR = 3.30, 95% CI 1.920 to 5.653), prone versus semisitting/sitting position ( p = 0.0036, OR = 3.58, 95% CI 1.451 to 11.881), number of operative levels ( p < 0.0001, OR = 1.42, 95% CI 1.247 to 1.605), intraoperative transfusions ( p = 0.0231, OR = 2.57, 95% CI 1.152 to 5.132), and nonspecific autoimmune disease ( p = 0.0107, OR = 3.83, 95% CI 1.418 to 8.730). On multivariate analysis, number of operative levels ( p = 0.0053, OR = 1.27, 95% CI 1.075 to 1.496) and nonspecific autoimmune disease ( p = 0.0416, OR 2.95, 95% CI 1.047 to 7.092) remained significant. Conclusions Although this study partially supports a mechanical etiology in the pathogenesis of a DCP, we also describe a notable correlation with autoimmune risk factors. Bilateral and multimyotomal involvement provides additional support that some DCPs may result from an inflammatory response and thus an underlying multifactorial etiology for this complication.

Study Design Retrospective study. Objective Efficient use of operating room time is important, as delays during induction or recovery increase time not spent operating while in the operating room. We identified factors that increase anesthetized, nonoperative time by utilizing a database of over 5,000 consecutive neurosurgical spine cases. Methods Surgical records were searched to identify all spine surgeries performed between January 2010 and July 2012. Anesthetized, nonoperative time was calculated from the anesthesia record and compared with both patient and procedure characteristics to determine any significant relationships Results There were 5,515 surgical cases with a mean age of 60.5 and mean body mass index (BMI) of 29.7; 3,226 (58%) were male subjects. There were 1,176 (21%) fusion cases, and level of pathology was predominantly lumbar (4,010 cases, 73%). Fusion cases had a significantly longer total anesthetized, nonoperative time (fusion: 98 minutes, nonfusion: 76 minutes, mean difference: 22 minutes, p < 0.0001). Significant factors affecting anesthetized, nonoperative time in nonfusion cases include age greater than 65 years (mean difference 5 minutes, p < 0.0001), American Society of Anesthesiologists (ASA) grade, and BMI (BMI < 25: 72 ± 1.2 minutes, BMI 25 to 29: 74 ± 0.6 minutes, BMI 30 to 39: 79 ± 0.6 minutes, BMI 40 + : 87 ± 1.8 minutes, p < 0.0001). Similarly, for fusion operations, age > 65 years significantly increased nonoperative time (mean difference 6 minutes, p < 0.01), as did increasing ASA (mean difference 9 minutes, p < 0.0001) and increasing BMI. Conclusion Patient and surgical factors, including ASA grade, BMI, level of pathology, and surgical approach, have noticeable effects on anesthetized, nonoperative times in spine surgery.

OBJECT External ventricular drainage (EVD) after intraventricular hemorrhage (IVH) without symptomatic hydrocephalus is controversial. The object of this study was to examine indicators or the timeframe for hydrocephalus in patients not immediately treated with EVD after IVH. METHODS Records from 2007 to 2014 were searched for “intraventricular hemorrhage” or “IVH.” Inclusion criteria were IVH after intracerebral hemorrhage (ICH), trauma, tumor, or vascular anomalies. Exclusion criteria were IVH with more than minimal subarachnoid hemorrhage, catastrophic ICH, layering IVH only, or hydrocephalus treated immediately with EVD. IVH was measured with the modified Graeb Score (mGS). An mGS of 5 indicates a full ventricle with dilation. Statistics included chi-square, Student’s t-test, and Mann-Whitney tests; receiver operating characteristics; and uni- and multivariate logistic regression. RESULTS One hundred five patients met the criteria; of these, 30 (28.6%) required EVD. Panventricular IVH was the most common pattern (n = 49, 46.7%), with 25 of these patients (51%) requiring EVD. The median mGS was 18 ± 5.4 (range 12–29) and 9 ± 4.5 (range 2–21) in the EVD and No-EVD groups, respectively (p < 0.001). Factors associated with EVD were radiological hydrocephalus at presentation, midline shift > 5 mm, Glasgow Coma Scale (GCS) score < 8, mGS > 13, third ventricle mGS = 5, and fourth ventricle mGS = 5. On multivariate analysis, GCS score < 8 [4.02 (range 1.13–14.84), p = 0.032], mGS > 13 [3.83 (range 1.02–14.89), p = 0.046], and fourth ventricle mGS = 5 [5.01 (range 1.26–22.78), p = 0.022] remained significant. Most patients treated with EVD (n = 25, 83.3%) required it soon after presentation [6.4 ± 3.3 (range 1.5–14) hrs]. The remaining 5 patients (16.7%) had a delayed EVD requirement [70.7 ± 22.7 (range 50–104.5) hrs]. CONCLUSIONS In this study population, the risk for EVD was variable, but greater with mGS > 13, coma, and a dilated fourth ventricle. While the need for EVD occurs within the 1st day after IVH in most patients, a minority require EVD after 48 hours.

Study Design Retrospective case series. Objective To determine the effect of obesity on the resource utilization and cost in 3270 consecutive patients undergoing elective noninstrumented decompressive surgeries for degenerative spine disease at Mayo Clinic Rochester between 2005 and 2012. Methods Groups were assessed for baseline differences (age, gender, and American Society of Anesthesiologists [ASA] classification, procedure type, and number of operative levels). Outcome variables included the transfusion requirements during surgery, the total anesthesia and surgical times, intensive care unit (ICU) admissions, standardized costs, as well as the ICU and hospital length of stay (LOS). Regression analysis was used to evaluate for strength of association between obesity and outcome variables. Results Baseline differences between the groups (nonobese: n = 1,853; obese: n = 1,417) were found with respect to age, ASA class, gender, procedure type, and number of operative levels. After correcting for differences, we found significant associations between obesity and surgical ( p < 0.0001) and anesthesia times ( p < 0.0001) and hospital LOS ( p < 0.0001). Additionally, ICU admission rates ( p = 0.02) and requirement for postoperative ventilation ( p = 0.048) were significantly higher in obese patients. Finally, mean difference in total cost ($1,632, p < 0.0001) was significantly higher for the obese cohort. Conclusion Obesity is associated with increased resource utilization and cost in patients undergoing a noninstrumented decompressive surgery for degenerative spine disease.

OBJECT Motocross racing is a popular sport; however, its impact on the growing/developing pediatric spine is unknown. Using a retrospective cohort model, the authors compared the degree of advanced degenerative findings in young motocross racers with findings in age-matched controls. METHODS Patients who had been treated for motocross-related injury at the authors' institution between 2000 and 2007 and had been under 18 years of age at the time of injury and had undergone plain radiographic or CT examination of any spinal region were eligible for inclusion. Imaging was reviewed in a blinded fashion by 3 physicians for degenerative findings, including endplate abnormalities, loss of vertebral body height, wedging, and malalignment. Acute pathological segments were excluded. Spine radiographs from age-matched controls were similarly reviewed and the findings were compared. RESULTS The motocross cohort consisted of 29 riders (mean age 14.7 years; 82% male); the control cohort consisted of 45 adolescents (mean age 14.3 years; 71% male). In the cervical spine, the motocross cohort had 55 abnormalities in 203 segments (average 1.90 abnormalities/patient) compared with 20 abnormalities in 213 segments in the controls (average 0.65/patient) (p = 0.006, Student t-test). In the thoracic spine, the motocross riders had 51 abnormalities in 292 segments (average 2.04 abnormalities/patient) compared with 25 abnormalities in 299 segments in the controls (average 1.00/patient) (p = 0.045). In the lumbar spine, the motocross cohort had 11 abnormalities in 123 segments (average 0.44 abnormalities/patient) compared with 15 abnormalities in 150 segments in the controls (average 0.50/patient) (p = 0.197). CONCLUSIONS Increased degenerative changes in the cervical and thoracic spine were identified in adolescent motocross racers compared with age-matched controls. The long-term consequences of these changes are unknown; however, athletes and parents should be counseled accordingly about participation in motocross activities.

OBJECT Off-road motorcycling is a very popular sport practiced by countless people worldwide. Despite its popularity, not much has been published on the severity and distribution of central nervous system–related injuries associated with this activity in the pediatric population. The purpose of this study was to confirm, characterize, and document the rate of head and spine injuries associated with off-road motorcycling in this population. METHODS All patients aged 18 years or less who were treated for a motorbike injury at the authors' institution (a Level 1 regional trauma center) between 2000 and 2007 were identified through in-house surgical and trauma registries. Type, mechanism, and severity of CNS-related injuries were assessed, including: incidence of traumatic brain injury (TBI), loss of consciousness (LOC), Glasgow Coma Scale (GCS) score, head CT findings, neurological deficits, spinal fractures, cervical strain, and use of protective gear, including helmets. RESULTS During the 8-year period of study, 298 accidents were evaluated in 248 patients. The patients' mean age at the time of injury was 14.2 ± 2.7 years. Head injury or TBI was identified in 60 (20.1%) of 298 cases (involving 58 of 248 patients). Fifty-seven cases were associated with LOC, and abnormalities were identified on head CT in 10 patients; these abnormalities included skull fractures and epidural, subdural, subarachnoid, and intraparenchymal hemorrhages. The GCS score was abnormal in 11 cases and ranged from 3 to 15, with an overall mean of 14.5. No patients required cranial surgery. Helmet use was confirmed in 43 (71.6%) of the cases involving TBI. Spine fractures were identified in 13 patients (4.3%) and 5 required surgical fixation for their injury. CONCLUSIONS The authors found a high occurrence of head injuries following pediatric off-road motorcycle riding or motocross accidents despite the use of helmets. Additionally, this study severely underestimates the rate of mild TBIs in this patient population. Our data indicate that motocross is a high-risk sport despite the use of protective gear. Riders and parents should be counseled accordingly about the risks prior to participation.

OBJECT Delayed cervical palsy (DCP) is a known complication following cervical spine surgery. While most DCPs eventually improve, they can result in significant temporary disability. Postoperative complications affect hospital length of stay (LOS) as well as overall hospital cost. The authors sought to determine the hospital cost of DCP after cervical spine fusion operations. METHODS A retrospective review of patients undergoing cervical fusion for degenerative disease at the Mayo Clinic from 2008 to 2012 was performed. Patients who developed DCPs not attributable to intraoperative trauma were included. All nonoperative-related costs were compared with similar costs in a control group matched according to age, sex, and surgical approach. All costs and services were reflective of the standard costs for the current year. Raw cost data were presented using ratios due to institutional policy against publishing cost data. RESULTS There were 27 patients (18 men, 9 women) who underwent fusion and developed a DCP over the study period. These patients were compared with 24 controls (15 men, 9 women) undergoing fusion in the same time period. There was no difference between patients and controls in mean age (62.4 ± 3.1 years vs 63.8 ± 2.5 years, respectively; p = 0.74), LOS (4.2 ± 3.3 days vs 3.8 ± 4.5 days, respectively; p = 0.43), or operating room–related costs (1.08 ± 0.09 vs 1.0 ± 0.07, respectively; p = 0.58). There was a significant difference in nonoperative hospital-related costs between patients and controls (1.67 ± 0.15 vs 1.0 ± 0.09, respectively; p = 0.04). There was a significantly higher utilization of postoperative imaging (CT or MRI) in the DCP group (14/27, 52%) when compared with the matched cohort (4/24, 17%; p = 0.018), and a significantly higher utilization of physiatry services (24/27 [89%] vs 15/24 [63%], respectively; p = 0.046). CONCLUSIONS While DCPs did not significantly prolong the length of hospitalization, they did increase hospital-related costs. This method could be further extrapolated to model costs of other complications as well.

Object The object of this study was to assess outcomes after surgery for recurrent intracranial glioma. Methods The authors retrospectively reviewed cases involving adult patients with intracranial glioma patients undergoing initial surgery (biopsy or resection) and one or more additional surgeries at their institution. Results A total of 323 operations were performed in 131 patients. The median survival was 76 months after first surgery, 36 months after second, 24 months after third, and 26.5 months after 4 or more surgeries. The overall complication rate was 12.8% after first surgery, 27.0% after second (OR 2.52, p = 0.0068), 22.0% after third (OR 1.92, not statistically significant [NS]), and 22.2% after 4 or more (OR 1.95, NS). Neurological complications occurred in 4.8% of patients at first surgery, 12.1% at second (OR 2.7, p = 0.0437), 8.2% at third (OR 1.75, NS), and 11.1% at 4 or more surgeries (OR 2.4583, NS). Regional complications occurred in 6.2% after first surgery, 9.9% after second surgery (OR 2.30, p = 0.095), 13.7% after third surgery (OR 3.31, p = 0.015), and 22.2% after 4 or more surgeries (OR 5.95, p = 0.056). Systemic complications occurred in 3.2% after first surgery, in 7.3% after second surgery (OR 2.3, p = 0.NS), in 4.1% after third surgery (OR 1.3, NS), and 0% after 4 or more surgeries. Reduction in Karnofsky Performance Status score occurred in 0% after first surgery, 8.1% after second surgery (OR 3.13, p = 0.0018), 10.2% after third surgery (OR 5.52, p < 0.0001), and 11.1% after 4 or more surgeries (OR 1.037, NS). Conclusions Postoperative survival is relatively prolonged but complication risk increases in patients with glioma who undergo multiple cranial surgeries. The largest increase in neurological risk occurs between the first and second surgery. In contrast, regional complication risk increases consistently with each surgery. The risk of systemic complications is not significantly altered with increasing surgeries. However, these complications only result in a modestly increased risk of functional decline after 2 or more surgeries. These findings may help counsel patients considering multiple glioma surgeries.