Shivanand P Lad

Duke University Medical Center, Durham, North Carolina, United States

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Publications (91)252.41 Total impact

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    ABSTRACT: Failed Back Surgery Syndrome (FBSS) is notoriously refractory to treatment resulting in high health care utilization and high health care costs. Given the recent emphasis of cost-conscious care in the United States, we examined the trends in imaging use in FBSS over the past decade. Furthermore, the role of different types of imaging modalities MRI vs non-MRI is of interest when considering potential therapeutic interventions, including spinal cord stimulation (SCS), a common therapy for treating neuropathic pain in the FBSS population. We conducted a retrospective analysis using the Truven MarketScan database to analyze the rates of imaging use in FBSS patients between the years 2000 and 2009. Total imaging episodes were computed for magnetic resonance imaging (MRI), computed tomography (CT) scan, x-ray, ultrasound, and nuclear imaging. In order to compare imaging usage between years which contain different numbers of patients, imaging rates were calculated using number of imaging episodes per 1000 patient months for each year. The yearly imaging rates for each modality are outlined in Table 1. The overall imaging rate for FBSS patients increased by 39% over the past decade. Specifically, the MRI imaging rate increased 35% from 29.5 to 39.9, and the non-MRI imaging rate increased 39% from 305.1 to 424.1. All imaging modalities showed increased usage between 2000 and 2009 with the exception of x-ray. The x-ray rate remained relatively constant at 234.8 in 2000 and 238.6 in 2009. We found a trend for increased imaging use between 2000 and 2009 in FBSS patients, a population with already immense health care utilization and health care costs. Rates of both MRI and non-MRI imaging increased by 35% to 40% in a period of 10 years. The role of frequency and type of imaging modality utilized in evaluating FBSS patients will have a significant impact on overall health care expenses and therapeutic options, including SCS, going forward.
    Neurosurgery 08/2015; 62 Suppl 1, CLINICAL NEUROSURGERY:200-201. DOI:10.1227/01.neu.0000467074.09614.21 · 3.62 Impact Factor
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    ABSTRACT: Deep brain stimulation (DBS) is an established surgical therapy for medically refractory tremor disorders including essential tremor (ET) and is currently under investigation for use in a variety of other neurologic and psychiatric disorders. There is growing evidence that the anti-tremor effects of DBS for ET are directly related to modulation of the dentatorubrothalamic tract (DRT), a white matter pathway that connects the cerebellum, red nucleus, and ventral intermediate nucleus of the thalamus. Emerging white matter targets for DBS, like the DRT, will require improved three-dimensional (3D) reference maps of deep brain anatomy and structural connectivity for accurate electrode targeting. High-resolution diffusion MRI of postmortem brain specimens can provide detailed volumetric images of important deep brain nuclei and 3D reconstructions of white matter pathways with probabilistic tractography techniques. We present a high spatial and angular resolution diffusion MRI template of the postmortem human brainstem and thalamus with 3D reconstructions of the nuclei and white matter tracts involved in ET circuitry. We demonstrate registration of these data to in vivo, clinical images from patients receiving DBS therapy, and correlate electrode proximity to tractography of the DRT with improvement of ET symptoms. Hum Brain Mapp, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
    Human Brain Mapping 06/2015; 36(8). DOI:10.1002/hbm.22836 · 5.97 Impact Factor
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    ABSTRACT: Purpose To compare reoperations, health care utilization, and costs in lumbar spinal stenosis (LSS) patients undergoing interspinous process (ISP) device placement in an inpatient versus outpatient setting. Methods The MarketScan database (2007-2009) was queried for adults with LSS undergoing ISP device placement as a primary procedure. Reoperations, health care utilization, and costs in patients with at least 18 months of follow-up were analyzed. Chi-square and Student t tests were used to assess the differences in characteristics and outcomes between patients treated in the inpatient and outpatient setting. Results A total of 411 patients who underwent ISP device placement were identified; the mean age was 72 years, 51% were female, and most patients were insured by Medicare (73.7%). The average postoperative follow-up was 24.9 months. A subset of 182 patients (44.3%) had inpatient procedures; 229 (55.7%) underwent outpatient ISP device placements. The overall reoperation rate was 20.4%. ISP reoperation rates between inpatient and outpatient cohorts were comparable (23.1% versus 18.3%; p = 0.24). Inpatients accrued significantly higher index procedural costs compared with outpatients ($17,432 versus $8854; p = 0.0001), however, the outpatient cohort utilized more postoperative outpatient services (143 versus 112; p = 0.09) and higher outpatient service costs ($25,376 versus $15,481; p = 0.01). Consequently, cumulative overall cost was similar among the two cohorts ($51,059 versus $51,778; p = 0.94). Conclusions Long-term reoperation rates following ISP device placement are comparable in the inpatient and outpatient setting. Upfront cost savings may be achieved with outpatient ISP device placement, but this benefit is lost by 18 months following initial surgery. Georg Thieme Verlag KG Stuttgart · New York.
    Journal of Neurological Surgery. Part A: Central European Neurosurgery 04/2015; DOI:10.1055/s-0034-1382785 · 0.61 Impact Factor
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    ABSTRACT: Introduction We evaluated outcome and resource utilization disparities between commercially insured, Medicaid, and Medicare patients. We further analyzed racial disparities in a subset cohort. Methods We reviewed the MarketScan database (2000-2009) for adult traumatic brain injury (TBI) patients. Analyses were performed to evaluate outcome differences by insurance type and race. Outpatient service utilization disparities by insurance and race were also evaluated. Results Our study included 92,159 TBI patients, 44,108 (47.9%) of whom utilized commercial insurance, 19,743 (21.4%) utilized Medicaid, and 28,308 (30.7%) utilized Medicare. In-hospital mortality was lowest for commercially insured (5.0%) versus 7.6% and 8.5% for Medicaid and Medicare patients, respectively (p < 0.0001). Medicaid patients had a longer hospitalization than commercially insured (12 days versus 6 days; p < 0.0001). Medicaid patients were 1.29 and 1.78 times more likely to die and experience complications than the commercially insured. Females had a lower mortality risk (odds ratio [OR]: 0.80, p < 0.0001) and less complications (OR: 0.67; p < 0.0001) than males. Higher comorbidities increased mortality risk (OR: 2.71; p < 0.0001) and complications (OR: 2.96, p < 0.0001). Mild injury patients had lower mortality (OR: 0.01; p < 0.0001) and less complications (OR: 0.07; p < 0.0001). Medicare (OR: 1.33; p < 0.0001) and higher comorbidity (OR: 1.26; p < 0.0001) patients utilized outpatient rehabilitation services more frequently. Medicare patients had twice the emergency department visits as the commercially insured (p < 0.0001). Medicare (16.6%) patients utilized more rehabilitation than commercially insured (13.4%) and Medicaid (9.1%) patients. Racial disparities were analyzed in a subset of 12,847 white and 4,780 African American (AA) patients. Multivariate analysis showed that AAs were more likely to experience a complication than white patients (OR: 1.13; p = 0.0024) and less likely to utilize outpatient rehabilitation services (OR: 0.83; p = 0.0025) than whites. Conclusions Insurance and racial disparities continue to exist for TBI patients. Insurance status appears to have an impact on short- and long-term outcomes to a greater degree than patient race. Georg Thieme Verlag KG Stuttgart · New York.
    Journal of Neurological Surgery. Part A: Central European Neurosurgery 03/2015; 76(03). DOI:10.1055/s-0034-1543958 · 0.61 Impact Factor
  • Shervin Rahimpour · Dennis A Turner · Shivanand P Lad
    JAMA Neurology 03/2015; 72(3):368. DOI:10.1001/jamaneurol.2014.4219 · 7.42 Impact Factor
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    ABSTRACT: Few studies have measured outcome differences between the various available spinal fusion techniques. We compare long-term outcomes of anterior versus posterior lumbar interbody fusion. Using the MarketScan database (Truven Health Analytics, Ann Arbor, MI, USA) we selected patients ⩾18years old who underwent lumbar fusion surgery from 2000-2009 using either approach. Exclusion criteria included circumferential fusion, and having less than 1year of preoperative or less than 2years of postoperative follow-up. Using an inverse probability-weighted propensity-score model we compared reoperation and 90day complication rates, and postoperative health resource utilization of both approaches. A total of 10,941 patients were identified. Of these, 7460 (68.2%) and 3481 (31.8%) underwent posterior and anterior interbody fusion, respectively. Anterior fusion patients had a higher 2year reoperation rate (odds ratio 1.43, 95% confidence interval [CI]: 1.21-1.70, p<0.0001), although differences became non-significant at maximum follow-up (p=0.0877). The 90day complication rate was 15.7%, with anterior fusion patients being more likely to experience complications (relative risk 1.24, 95%CI: 1.13-1.36, p<0.0001). Anterior fusion patients also had greater levels of postoperative health utilization, surpassing posterior fusion patients by an average of $US7450 in total charges (95% CI: $4670-$10,220, p<0.0001). As currently practiced in the USA, anterior lumbar surgical approaches may be associated with higher postoperative morbidity and reoperation rates than posterior fusion approaches. Copyright © 2015. Published by Elsevier Ltd.
    Journal of Clinical Neuroscience 02/2015; 22(5). DOI:10.1016/j.jocn.2014.11.016 · 1.38 Impact Factor
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    ABSTRACT: Essential tremor (ET) was the original indication for deep brain stimulation (DBS), with USA Food and Drug Administration approval since 1997. Despite the efficacy of DBS, it is associated with surgical complications that cause sub-optimal clinical outcomes. Given that ET is a progressive disease with increase in symptom severity with increasing age, this study evaluated the impact of increasing age on short-term complications following DBS surgery for ET. The Thomson-Reuters MarketScan database was utilized (New York, NY, USA). Patients selected were over age 18 and underwent DBS for ET between the years 2000 and 2009. Multivariable logistic regression analysis was used to calculate complication odds ratios (OR) for a 5year increase in age, after controlling for other covariates. Six hundred sixty-one patients were included in the analysis. The mean (standard deviation) age was 61.9 (14.3) years, with 17% of individuals aged ⩾75years. Overall 56.9% of patients were male, and 44.6% had a Charlson Comorbidity Score of ⩾1. Additionally, 7.1% of patients experienced at least one complication within 90days, including wound infections (3.0%), pneumonia (2.4%), hemorrhage or hematoma (1.5%), or pulmonary embolism (0.6%). Increasing age was not significantly associated with the overall 90day complication rates (OR 0.89; 95% confidence interval [CI] 0.77-1.02; p=0.102). The risk of the two most common procedure-related complications, hemorrhage and infection, did not significantly increase with age (hemorrhage: OR 1.02; 95%CI 0.77-1.37; p=0.873; and infection: OR 0.88; 95%CI 0.72-1.07; p=0.203). Our findings suggest that age should not be a primary exclusion factor for determining candidacy for DBS and also suggest a possible expansion of the traditional therapeutic window since post-operative complications remained relatively stable. Copyright © 2014 Elsevier Ltd. All rights reserved.
    Journal of Clinical Neuroscience 02/2015; 22(5). DOI:10.1016/j.jocn.2014.11.005 · 1.38 Impact Factor
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    Bryan Howell · Shivanand P Lad · Warren M Grill
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    ABSTRACT: Spinal cord stimulation (SCS) is an alternative or adjunct therapy to treat chronic pain, a prevalent and clinically challenging condition. Although SCS has substantial clinical success, the therapy is still prone to failures, including lead breakage, lead migration, and poor pain relief. The goal of this study was to develop a computational model of SCS and use the model to compare activation of neural elements during intradural and extradural electrode placement. We constructed five patient-specific models of SCS. Stimulation thresholds predicted by the model were compared to stimulation thresholds measured intraoperatively, and we used these models to quantify the efficiency and selectivity of intradural and extradural SCS. Intradural placement dramatically increased stimulation efficiency and reduced the power required to stimulate the dorsal columns by more than 90%. Intradural placement also increased selectivity, allowing activation of a greater proportion of dorsal column fibers before spread of activation to dorsal root fibers, as well as more selective activation of individual dermatomes at different lateral deviations from the midline. Further, the results suggest that current electrode designs used for extradural SCS are not optimal for intradural SCS, and a novel azimuthal tripolar design increased stimulation selectivity, even beyond that achieved with an intradural paddle array. Increased stimulation efficiency is expected to increase the battery life of implantable pulse generators, increase the recharge interval of rechargeable implantable pulse generators, and potentially reduce stimulator volume. The greater selectivity of intradural stimulation may improve the success rate of SCS by mitigating the sensitivity of pain relief to malpositioning of the electrode. The outcome of this effort is a better quantitative understanding of how intradural electrode placement can potentially increase the selectivity and efficiency of SCS, which, in turn, provides predictions that can be tested in future clinical studies assessing the potential therapeutic benefits of intradural SCS.
    PLoS ONE 12/2014; 9(12):e114938. DOI:10.1371/journal.pone.0114938 · 3.23 Impact Factor
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    ABSTRACT: The aim of this study was to compare reoperation, complication rates, and healthcare resource utilization of expansile laminectomies with instrumented fusion versus laminoplasty. Using the MarketScan database (Truven Health Analytics, Ann Arbor, MI, USA), we selected patients aged >18 years who underwent either cervical laminoplasty or laminectomy with fusion between 2000–2009. Propensity score modeling produced a matched cohort balanced for age, sex, comorbidities, and other relevant factors. A total of 3185 patients meeting our inclusion criteria also had 2 year follow-up available. Of these, 2927 (91.90%) and 258 (8.10%) had laminectomy with fusion and laminoplasty, respectively. Laminoplasty patients had significantly lower complication rates during index hospitalization (5.81 versus 9.62%, adjusted odds ratio [aOR]: 0.556, 95% confidence interval [CI]: 0.418–0.740, p < 0.0002), during 30 day (6.87 versus 11.12%, aOR: 0.568, 95% CI: 0.436–0.740, p < 0.0002) and 90 day (7.61 versus 11.78%, aOR: 0.593, 95% CI: 0.460–0.764, p < 0.0002) postoperative periods. They also had lower costs (United States dollars) during index hospitalization ($26,129 versus $35,483, p < 0.0004), and overall during the 2 year postoperative period ($77,960 versus $106,453, p < 0.0001). Two year reoperation rates were similar between both groups (9.77% versus 7.36%, p = 0.20). Our study suggests that cervical laminoplasty has significantly lower complication rates, similar long-term reoperation rates and lower healthcare resource utilization after 2 years than laminectomy with fusion.
    Journal of Clinical Neuroscience 12/2014; 22(3). DOI:10.1016/j.jocn.2014.10.001 · 1.38 Impact Factor
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    ABSTRACT: Object: Recent studies have reported that the local delivery of vancomycin powder is associated with a decrease in spinal surgical site infection. This retrospective cohort study compares posterior cervical fusion cases before and after the routine application of spinal vancomycin powder to evaluate the ability of local vancomycin powder to prevent deep wound infection after posterior cervical spinal fusion. Methods: Posterior cervical fusion spinal surgeries performed at a single institution were reviewed from January 2011 to July 2013. Each cohort's baseline characteristics, operative data, and rates of wound infection were compared. Associations between infection and vancomycin powder, with and without propensity score adjustment for risk factors, were determined using logistic regression. Results: A total of 289 patients (174 untreated and 115 treated with vancomycin powder) were included in the study. The cohorts were similar in terms of baseline and operative variables. No significant change in deep wound infection rate was seen between the control group (6.9%) and intervention group (5.2%, p = 0.563). Logistic regression, with and without propensity score adjustment, demonstrated that the use of vancomycin powder did not impact the development of surgical site infection (OR 0.743 [95% CI 0.270-2.04], p = 0.564) and (OR 0.583 [95% CI 0.198-1.718], p = 0.328), respectively. Conclusions: Within the context of an ongoing debate on the effectiveness of locally administered vancomycin powder, the authors found no significant difference in the incidence of deep wound infection rates after posterior cervical fusion surgery with routine use of locally applied vancomycin powder. Future prospective randomized series are needed to corroborate these results.
    Journal of Neurosurgery Spine 11/2014; 22(1):1-8. DOI:10.3171/2014.9.SPINE13826 · 2.38 Impact Factor
  • Ranjith Babu · Shivanand P. Lad
    Journal of Neurosurgery Spine 10/2014; 21(4):500-501. · 2.38 Impact Factor
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    ABSTRACT: Study Design Retrospective propensity score-matched cohort analysis of the Thomson Reuters MarketScan database. Purpose To compare the outcomes of vertebral compression fracture (VCF) treatment options, with an emphasis on reoperation, complications, costand overall healthcare resource use between 2005 and 2009 in the United States. Overview of Literature Options for the treatment of VCFs include conservative management, kyphoplasty, and vertebroplasty. The cost-effectiveness of surgical intervention for VCF has been criticized, and some suggest their outcomes to be similar to placebo. Methods Patients 18 years of age and older who developed a VCF were identified and separated into three treatment cohorts: vertebroplasty, kyphoplasty, and non-surgical. Propensity score matching was performed to match patients between cohorts. Main outcomes assessed included reoperation, complications, healthcare resource use and associated cost. Outcomes were compared at three separate time intervals (patients at index hospitalization; patients with at least 2-year follow-up data; and those with at least 4-year follow-up data). Results Twenty thousand seven hundred forty patients were identified with VCFs, yielding 7,290 after propensity score matching. The mean age of the patients was 78±12 years; and 5,507 (75.5%) were female. All reoperation rates ranged from 6%-17%, while complication rates ranged from 7%-10%, which did not differ significantly among the three cohorts at all follow-up periods. Overall costs were noted to be significantly greater in both the kyphoplasty and vertebroplasty groups at 1-year follow-up, not at 2-year and 4-year follow-up. Conclusions Our data suggests that the treatment of a VCF patient will likely be associated with similar long-term operative and complication rates regardless of treatment modality.
    Asian spine journal 10/2014; 8(5):605-14. DOI:10.4184/asj.2014.8.5.605
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    ABSTRACT: IMPORTANCE Deep brain stimulation (DBS) is a well-established modality for the treatment of advanced Parkinson disease (PD). Recent studies have found DBS plus best medical therapy to be superior to best medical therapy alone for patients with PD and early motor complications. Although no specific age cutoff has been defined, most clinical studies have excluded patients older than 75 years of age.We hypothesize that increasing age would be associated with an increased number of postoperative complications.
    JAMA Neurology 08/2014; 71(10). DOI:10.1001/jamaneurol.2014.1272 · 7.42 Impact Factor
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    ABSTRACT: Introduction: The Neuromodulation Appropriateness Consensus Committee (NACC) of the International Neuromodulation Society (INS) evaluated evidence regarding the safety and efficacy of neurostimulation to treat chronic pain, chronic critical limb ischemia, and refractory angina and recommended appropriate clinical applications. Methods: The NACC used literature reviews, expert opinion, clinical experience, and individual research. Authors consulted the Practice Parameters for the Use of Spinal Cord Stimulation in the Treatment of Neuropathic Pain (2006), systematic reviews (1984 to 2013), and prospective and randomized controlled trials (2005 to 2013) identified through PubMed, EMBASE, and Google Scholar. Results: Neurostimulation is relatively safe because of its minimally invasive and reversible characteristics. Comparison with medical management is difficult, as patients considered for neurostimulation have failed conservative management. Unlike alternative therapies, neurostimulation is not associated with medication-related side effects and has enduring effect. Device-related complications are not uncommon; however, the incidence is becoming less frequent as technology progresses and surgical skills improve. Randomized controlled studies support the efficacy of spinal cord stimulation in treating failed back surgery syndrome and complex regional pain syndrome. Similar studies of neurostimulation for peripheral neuropathic pain, postamputation pain, postherpetic neuralgia, and other causes of nerve injury are needed. International guidelines recommend spinal cord stimulation to treat refractory angina; other indications, such as congestive heart failure, are being investigated. Conclusions: Appropriate neurostimulation is safe and effective in some chronic pain conditions. Technological refinements and clinical evidence will continue to expand its use. The NACC seeks to facilitate the efficacy and safety of neurostimulation.
    Neuromodulation 08/2014; 17(6):515-550. DOI:10.1111/ner.12208 · 2.70 Impact Factor
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    ABSTRACT: IntroductionThe International Neuromodulation Society (INS) has identified a need for evaluation and analysis of the practice of neurostimulation of the brain and extracranial nerves of the head to treat chronic pain.Methods The INS board of directors chose an expert panel, the Neuromodulation Appropriateness Consensus Committee (NACC), to evaluate the peer-reviewed literature, current research, and clinical experience and to give guidance for the appropriate use of these methods. The literature searches involved key word searches in PubMed, EMBASE, and Google Scholar dated 1970–2013, which were graded and evaluated by the authors.ResultsThe NACC found that evidence supports extracranial stimulation for facial pain, migraine, and scalp pain but is limited for intracranial neuromodulation. High cervical spinal cord stimulation is an evolving option for facial pain. Intracranial neurostimulation may be an excellent option to treat diseases of the nervous system, such as tremor and Parkinson's disease, and in the future, potentially Alzheimer's disease and traumatic brain injury, but current use of intracranial stimulation for pain should be seen as investigational.Conclusions The NACC concludes that extracranial nerve stimulation should be considered in the algorithmic treatment of migraine and other disorders of the head. We should strive to perfect targets outside the cranium when treating pain, if at all possible.
    Neuromodulation 08/2014; 17(6). DOI:10.1111/ner.12215 · 2.70 Impact Factor
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    ABSTRACT: Object. The Accreditation Council for Graduate Medical Education (ACGME) implemented resident duty-hour restrictions on July 1, 2003, in concern for patient and resident safety. Whereas studies have shown that duty-hour restrictions have increased resident quality of life, there have been mixed results with respect to patient outcomes. In this study, the authors have evaluated the effect of duty-hour restrictions on morbidity, mortality, length of stay (LOS), and charges in patients who underwent spine surgery.
    Journal of Neurosurgery Spine 07/2014; 21(4):1-14. DOI:10.3171/2014.5.SPINE13283 · 2.38 Impact Factor
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    ABSTRACT: Objectives Conversion rates from trial leads to permanent spinal cord stimulation (SCS) systems have recently come under scrutiny. Our goal was to examine the rate of conversion from trial lead to permanent system placement as well as identify factors associated with successful SCS conversion.Materials and Methods We designed a large retrospective analysis using the Thomson Reuters MarketScan database. We included all patients who underwent a percutaneous trial of neurostimulatory electrodes from the years 2000 to 2009 who were aged 18 and older. Patients were then tracked to see if they went on to receive a permanent SCS system. Patients were also analyzed in univariate and multivariate models to identify factors associated with successful conversion.ResultsA total of 21,672 unique instances of percutaneous trials were identified. Overall, 41.4% of those receiving trials went on to have a permanent SCS system installed within the subsequent three months. Factors associated with increased likelihood of successful conversion included having commercial insurance (43% vs. 37%, p < 0.0001), younger age (43% for those aged 35-44 vs. 39% for those aged 65 and older, p < 0.0001), and never having had a previous percutaneous trial attempt (44% for first-time trials vs. 27% for those on their second trial vs. 14% for those on their third or later trial, p < 0.0001). In multivariate analysis, we found significant variation in conversion rate by geographic area (patients in the North Central region vs. Northeast region: odds ratio 1.48, 95% confidence interval [1.31, 1.66]; p < 0.0001).Conclusions In this study of a national cohort of patients, we identified specific factors associated with higher conversion rates, along with significant geographical variation. In general, there is a need for better patient selection by physicians who practice neuromodulation.
    Neuromodulation 06/2014; 18(2). DOI:10.1111/ner.12199 · 2.70 Impact Factor
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    ABSTRACT: Object: On July 1, 2003, the Accreditation Council for Graduate Medical Education (ACGME) implemented duty-hour restrictions for resident physicians due to concerns for patient and resident safety. Though duty-hour restrictions have increased resident quality of life, studies have shown mixed results with respect to patient outcomes. In this study, the authors have evaluated the effect of duty-hour restrictions on morbidity, mortality, length of stay, and charges in patients who underwent brain tumor and cerebrovascular procedures. Methods: The Nationwide Inpatient Sample was used to evaluate the effect of duty-hour restrictions on complications, mortality, length of stay, and charges by comparing the pre-reform (2000-2002) and post-reform (2005-2008) periods. Outcomes were compared between nonteaching and teaching hospitals using a difference-in-differences (DID) method. Results: A total of 90,648 patients were included in the analysis. The overall complication rate was 11.7%, with the rates not significantly differing between the pre- and post-duty hour eras (p = 0.26). Examination of hospital teaching status revealed that complication rates decreased in nonteaching hospitals (12.1% vs 10.4%, p = 0.0004) and remained stable in teaching institutions (11.8% vs 11.9%, p = 0.73) in the post-reform era. Multivariate analysis demonstrated a significantly higher complication risk in teaching institutions (OR 1.33 [95% CI 1.11-1.59], p = 0.0022), with no significant change in nonteaching hospitals (OR 1.11 [95% CI 0.91-1.37], p = 0.31). A DID analysis to compare the magnitude in change between teaching and nonteaching institutions revealed that teaching hospitals had a significantly greater increase in complications during the post-reform era than nonteaching hospitals (p = 0.040). The overall mortality rate was 3.0%, with a significant decrease occurring in the post-reform era in both nonteaching (5.0% vs 3.2%, p < 0.0001) and teaching (3.2% vs 2.3%, p < 0.0001) hospitals. DID analysis to compare the changes in mortality between groups did not reveal a significant difference (p = 0.40). The mean length of stay for all patients was 8.7 days, with hospital stay decreasing from 9.2 days to 8.3 days in the post-reform era (p < 0.0001). The DID analysis revealed a greater length of stay decrease in nonteaching hospitals than teaching institutions, which approached significance (p = 0.055). Patient charges significantly increased in the post-reform era for all patients, increasing from $70,900 to $96,100 (p < 0.0001). The DID analysis did not reveal a significant difference between the changes in charges between teaching and nonteaching hospitals (p = 0.17). Conclusions: The implementation of duty-hour restrictions correlated with an increased risk of postoperative complications for patients undergoing brain tumor and cerebrovascular neurosurgical procedures. Duty-hour reform may therefore be associated with worse patient outcomes, contrary to its intended purpose. Due to the critical condition of many neurosurgical patients, this patient population is most sensitive and likely to be negatively affected by proposed future increased restrictions.
    Journal of Neurosurgery 06/2014; 121(2):1-15. DOI:10.3171/2014.5.JNS1314 · 3.74 Impact Factor
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    ABSTRACT: Study Design. Retrospective cohort study.Objective. To investigate the association between preoperative baseline serum albumin and postoperative surgical complication.Summary of Background Data. The prevalence of malnutrition in the hospitalized patient population has only been recently recognized. Preoperative hypoalbuminemia (serum albumin < 3.5 g/dL) has been shown to be associated with increased morbidity and mortality rates. The prognostic implications and significance of hypoalbuminemia after spine fusion surgery remain unknown. In this study, we assess the predictive value of preoperative nutritional status (serum albumin level) on postoperative complication rates.Methods. The medical records of 136 consecutive patients undergoing spine fusion at our institution were reviewed. Preoperative serum albumin level was assessed on all patients and used to quantify nutritional status. Albumin less than 3.5 g/dL was recognized as hypoalbuminemia (malnourished). Patient demographics, comorbidities, and postoperative complication rates were collected. Patients were also stratified into two groups based on their etiology, namely elective degenerative/deformity versus non-elective cases. The association between preoperative serum albumin level and postoperative complication was assessed via logistic regression analysis.Results. Overall, 40 (29.4%) patients experience at least one postoperative complication. Patients undergoing elective surgery had more complications based on preoperative albumin levels (malnourished: 35.7% vs. nourished: 11.7%, p = 0.03), whereas those undergoing non-elective surgery had similar complication rates (malnourished: 46.5% vs. nourished: 42.1%, p = 0.75). For patients undergoing elective spinal surgery, logistic regression with and without propensity score adjustment for risk factors, demonstrated that preoperative serum albumin level was a significant predictor of postoperative complications (OR: 4.21, CI: 95% (1.09, 16.19), p = 0.04) and (OR: 4.54, CI: 95% (1.17, 19.32), p = 0.04), respectively.Conclusion. Preoperative hypoalbuminemia is an independent risk factor for postoperative complications following elective spine surgery for degenerative and deformity causes, and should be used more frequently as a prognostic tool to detect malnutrition and risk of adverse surgical outcomes.
    Spine 05/2014; 39(18). DOI:10.1097/BRS.0000000000000450 · 2.30 Impact Factor
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    ABSTRACT: Study Design. Retrospective, observational.Objective. To simulate what episodes-of-care in spinal surgery might look like in a bundled payment system and to evaluate the associated costs and characteristics.Summary of Background Data. Episode-based payment bundling has received considerable attention as a potential method to help curb the rise in healthcare spending and is being investigated as a new payment model as part of the Affordable Care Act. While earlier studies investigated bundled payments in a number of surgical settings, very few focused on spine surgery specifically.Methods. We analyzed data from MarketScan. Patients were included in the study if they underwent cervical or lumbar spinal surgery in 2000-2009, had at least 2 years pre-operative and 90 days post-operative follow-up data. Patients were grouped based on their Diagnosis Related Group (DRG) and then tracked in simulated episodes-of-care/payment bundles that lasted for the duration of 30, 60, and 90 days following the discharge from the index-surgical hospitalization. Total costs associated with each episode-of-care duration were measured and characterized.Results. A total of 196,918 patients met our inclusion criteria. Significant variation existed between DRGs, ranging from $11,180 (30-day bundle, DRG 491) to $107,642 (30-day bundle, DRG). There were significant cost variations within each individual DRG. Post-discharge care accounted for a relatively small portion of overall bundle costs (range 4-8% in 90-day bundles). Total bundle costs remained relatively flat as bundle-length increased (total average cost of 30-day: $33,522 vs. $35,165 for 90-day). Payments to hospitals accounted for the largest portion of bundle costs (76%)Conclusion. There exists significant variation in total healthcare costs for spinal surgery patients, even within a given DRG. Better characterization of impacts of a bundled payment system in spine surgery is important for understanding the costs of index procedure hospital, physician services and post-operative care on potential future healthcare policy decision making.
    Spine 05/2014; 39(15). DOI:10.1097/BRS.0000000000000378 · 2.30 Impact Factor

Publication Stats

964 Citations
252.41 Total Impact Points


  • 2012–2015
    • Duke University Medical Center
      • Division of Neurosurgery
      Durham, North Carolina, United States
    • University of Louisville
      Louisville, Kentucky, United States
  • 2011–2014
    • Duke University
      • Department of Surgery
      Durham, North Carolina, United States
  • 2006–2012
    • Stanford University
      • Department of Neurosurgery
      Palo Alto, California, United States
  • 2007–2008
    • Stanford Medicine
      • Department of Neurosurgery
      Stanford, California, United States