D-Dimer, Erythrocyte Sedimentation Rate, and C-Reactive Protein Sensitivities for Periprosthetic Joint Infection Diagnosis.

BACKGROUND: There is contradicting evidence on the diagnostic value of inflammatory biomarkers for periprosthetic joint infection (PJI). We sought to quantify the sensitivity of D-dimer for acute and chronic PJI diagnosis and evaluate D-dimer lab values in the 90-day postoperative window in a control cohort of primary joint arthroplasty patients for comparison. METHODS: An institutional database was queried for patients undergoing revision procedures for PJI after total hip arthroplasty (THA) and total knee arthroplasty (TKA) from 2014 to present. CRP, ESR, and D-dimer were collected within 90 days pre and postoperatively and sensitivities for the diagnosis of PJI were calculated. The control group included patients who underwent a negative diagnostic workup for deep venous thrombosis (DVT) or pulmonary embolus (PE) and had a D-dimer lab collected within 90 days postoperatively from primary total joint arthroplasty (TJA). RESULTS: A total of 604 PJI patients were identified, and 81 patients had D-dimer, ESR, and CRP collected. There were 50/81 acute PJI patients and 31/81 chronic PJI patients who had median D-dimer values of 2,136.5 ng/mL [interquartile range (IQR): 1,642-3,966.5] and 3,336 ng/mL [IQR: 1,976-5,594]. Only the chronic PJI group had significantly higher D-dimer values when compared to the control cohort (P = .009). The sensitivity of D-dimer was calculated to be 92% and 93.5% in the acute and chronic PJI groups, respectively. CONCLUSION: Serum D-dimer may not have high diagnostic utility for acute PJI, especially in the setting of recent surgery; however, it still may be useful for patients who have chronic PJI.

Direct Costs Vary by Outcome in Two-Stage Revision Arthroplasty for the Treatment of Hip Periprosthetic Joint Infection.

Background: Two-stage revision arthroplasty is the gold standard for treating chronic prosthetic joint infection (PJI), but there has been limited analysis of the costs incurred beyond the index procedure and how additional complications and/or surgeries impact the cost of care. Methods: The electronic health record was queried for patients who underwent a total hip arthroplasty complicated by PJI and then underwent removal of the prosthesis with implantation of an antibiotic-impregnated articulating cement spacer. Patient demographics, surgical variables, hospital readmissions, emergency department (ED) visits, and postoperative complications were recorded. Data on total costs were collected with an internal accounting database. The average follow-up duration was 3.35 years. Results: Univariate analyses showed statistically significant differences between outcome groups (reimplantation, reimplantation requiring later revision, retained spacer, and Girdlestone resection arthroplasty) in total overall costs, ED visit costs, and postoperative costs at 1 and 2 years after the initial spacer placement. The median total cost at 2 years for each group was $38,865 ($29,144-49,471) (reimplantation), $79,223 ($53,442-100,152) (reimplantation with revision), $54,096 ($20,872-73,903) (retained spacer), $62,134 ($52,135-101,546) (Girdlestone). Patients who underwent successful reimplantation requiring no further surgery had significantly lower total costs than patients who needed revision surgeries after reimplantation ($38,865 [$29,144-49,471] vs $79,223 [$53,442-100,152], P = .007). Patients with a Girdlestone resection arthroplasty had higher total costs at 1 year ($59,708 [$41,781-80,916] vs $33,093 [$27,237-40,429], P = .043) and higher costs attributable to ED visits at 2 years than the reimplantation group ($23,581 [$14,029-41,519] vs $15,307 [$6291-29,119], P = .009). Conclusions: A significant variation exists among total costs for the 2-stage treatment of hip PJI when stratified by the final outcome.

Cost Drivers in Two-Stage Treatment of Hip Periprosthetic Joint Infection With an Antibiotic Coated Cement Hip Spacer.

BACKGROUND: The current gold standard for treating chronic Periprosthetic Joint Infection (PJI) is a 2-stage revision arthroplasty. There has been little investigation into what specific patient and operative factors may be able to predict higher costs of this treatment. METHODS: An institutional electronic health record database was retrospectively queried for patients who developed a PJI after a total hip arthroplasty, and underwent removal of the prosthesis and implantation of an antibiotic-impregnated articulating hip cement spacer. Patient demographics, surgical variables, hospital readmissions, emergency department visits, and post-operative complications were collected. Total costs were captured through an internal accounting database through 2 years post-operatively. Negative binomial regressions were utilized for multivariable analyses. A total of 55 hips with PJI were available for cost analyses. RESULTS: A comorbidity index score was associated with a 70% increase (Odds Ratio (OR): 1.7 [1.18-2.5], P = .003) in total costs at 2-years. Illicit drug use was associated with a 70% increase in costs at 1-year post-operatively (OR 1.7 [1.18-2.5], P = .003). Metal-on-poly liners were associated with a 22% decrease in cost at 2-years post-operatively when compared to Cement-on-Bone articulating spacers, and Metal-on-poly -constrained liners accounted for 38% lower costs at 1-year (OR 0.62 [0.44-0.87], P = .004). Use of an intraoperative extended trochanteric osteotomy was associated with a 46 and 61% increase in cost at 1-year (OR 1.46 [1.14-1.89]) and 2-years (OR 1.61 [1.26-2.07], P < .001) post-operatively. CONCLUSION: Age, comorbidity index score, drug use, and extended trochanteric osteotomy were associated with increased costs of PJI treatment. This may be used to improve reimbursement models and target areas of cost savings.

A Nationwide Analysis of Aneurysmal Subarachnoid Hemorrhage Mortality, Complications, and Health Economics in the USA.

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating neurological condition. Endovascular coiling or surgical clipping have equivocal success rates, but relatively little is known regarding the health economics and complications of these procedures at the population level. We aimed to analyze the complication profiles and healthcare resource utilization (HRCU) associated with the treatment of aSAH in the USA. We performed a retrospective analysis utilizing the IBM MarketScan database between 2008 and 2015. Primary outcomes included economic analysis stratified by post-operative complication; determination of the effect of several factors on total cost by multivariable regression; and analysis of the incidence, timing, and associated HCRU of aSAH-related post-operative complications. Of the 2374 patients meeting inclusion criteria for economic analysis, 1783 (75.1%) patients had at least one of the ten complications. The most common complications included hydrocephalus (43.8%), transient cerebral ischemia (including vasospasm) (30.6%), ischemic stroke (29.1%), syndrome of inappropriate antidiuretic hormone (SIADH)/hyposmolarity/hyponatremia (22.1%), and seizures (14.9%). Patients who experienced complications had higher median 90-day total costs [$161,127 (Q1 to Q3, $101,411 to $257,662)] than those who did not [$97,376 (Q1 to Q3, $55,692 to $147,447)]. Length of stay was longest for those with pulmonary embolism and pneumonia (27 days) and shortest for those with SIADH/hyposmolarity/hyponatremia (16 days). Brain compression/herniation had the highest mortality rate (19.5%). In total, 14.6% of all patients experienced a readmission within 30 days. In conclusion, patients with aSAH have high post-operative complication rates and costs. Development of novel interventions to reduce complications and improve outcomes is crucial.

Treatment Patterns and Health Care Resource Utilization of Iatrogenic Spinal Cerebrospinal Fluid Leaks in the United States.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: We aimed to characterize the treatment patterns and the associated costs in patients with cerebrospinal fluid (CSF) leak after spine procedures in the United States. BACKGROUND: CSF leak is a common complication after spinal procedures. However, there is a little data regarding the national patterns of treatment choice and the associated health care resource utilization. METHODS: We utilized the IBM MarketScan Research databases to retrospectively analyze adult US patients diagnosed with CSF leak within 30 days of spine procedures between 2001 and 2018. Treatment prevalence, treatment failure, and health care resource utilization data within 30 days of the CSF leak were collected. A subanalysis was performed on patients who received epidural blood patches (EBP) to better understand health care utilization attributable to this treatment modality. RESULTS: Twenty one thousand four hundred fourteen patients were identified. The most common causes of CSF leak were diagnostic spinal tap (59.2%) and laminectomy/discectomy (18.7%). With regard to treatment prevalence, 40.4% of the patients (n=8651) had conservative medical management, 46.6% (n=9987) received epidural blood patch repair, 9.6% required surgical repair (n=2066), and 3.3% (n=710) had lumbar drain/puncture. Nine hundred sixty-seven (9.7%), 150 (21.1%), and 280 (13.5%) patients failed initial EBP, lumbar drain, and surgery, respectively, and the overall failure rate was 10.9% (n=1397). The median 30-day total cost across all groups was $5,101. Patients who received lumbar drain ($22,341) and surgical repair ($30,199) had higher 30-day median total costs than EBP ($8,140) or conservative management ($17,012). The median 30-day total cost for patients whose EBP failed ($8,179) was substantially greater than those with a successful EBP repair ($3,439). CONCLUSIONS: National treatment patterns and costs for CSF leaks were described. When used in the correct patient cohort, EBP has the lower failure rates and costs than comparable alternatives. EBP may be considered more often in situations where conservative management or lumbar drains are currently being used.

Machine Learning to Predict Successful Opioid Dose Reduction or Stabilization After Spinal Cord Stimulation.

BACKGROUND: Spinal cord stimulation (SCS) effectively reduces opioid usage in some patients, but preoperatively, there is no objective measure to predict who will most benefit. OBJECTIVE: To predict successful reduction or stabilization of opioid usage after SCS using machine learning models we developed and to assess if deep learning provides a significant benefit over logistic regression (LR). METHODS: We used the IBM MarketScan national databases to identify patients undergoing SCS from 2010 to 2015. Our models predict surgical success as defined by opioid dose stability or reduction 1 year after SCS. We incorporated 30 predictors, primarily regarding medication patterns and comorbidities. Two machine learning algorithms were applied: LR with recursive feature elimination and deep neural networks (DNNs). To compare model performances, we used nested 5-fold cross-validation to calculate area under the receiver operating characteristic curve (AUROC). RESULTS: The final cohort included 7022 patients, of whom 66.9% had successful surgery. Our 5-variable LR performed comparably with the full 30-variable version (AUROC difference <0.01). The DNN and 5-variable LR models demonstrated similar AUROCs of 0.740 (95% CI, 0.727-0.753) and 0.737 (95% CI, 0.728-0.746) ( P = .25), respectively. The simplified model can be accessed at SurgicalML.com . CONCLUSION: We present the first machine learning-based models for predicting reduction or stabilization of opioid usage after SCS. The DNN and 5-variable LR models demonstrated comparable performances, with the latter revealing significant associations with patients' pre-SCS pharmacologic patterns. This simplified, interpretable LR model may augment patient and surgeon decision making regarding SCS.

Interscalene block with liposomal bupivacaine versus continuous interscalene catheter in primary total shoulder arthroplasty.

BACKGROUND: Multimodal pain regimens in total shoulder arthroplasty (TSA) now include regional anesthetic techniques. Historically, regional anesthesia for extended postoperative pain control in TSA was administered using a continuous interscalene catheter (CIC). Liposomal bupivacaine (LB) is used for its potential for similar pain control and fewer complications compared with indwelling catheters. We evaluated the efficacy of interscalene LB compared with a CIC in postoperative pain control for patients undergoing TSA. METHODS: This was a retrospective cohort study at a tertiary-care academic medical center including consecutive patients undergoing primary anatomic or reverse TSA from 2016 to 2020 who received either single-shot LB or a CIC for perioperative pain control. Perioperative and outcome variables were collected. The primary outcome was postoperative pain control, whereas the secondary outcome was health care utilization. RESULTS: The study included 565 patients, with 242 in the CIC cohort and 323 in the LB cohort. Demographic characteristics including sex (P = .99) and race (P = .81) were similar between the cohorts. The LB cohort had significantly lower mean pain scores at 24 hours (3 vs. 2, P < .001) and 36 hours (3 vs. 2, P < .001) postoperatively. The CIC cohort showed a higher percentage of patients experiencing a pain score of 9 or 10 postoperatively (29% vs. 17%, P = .001), whereas the LB cohort had a significantly greater proportion of opioid-free patients (32% vs. 10%, P < .001). Additionally, a greater proportion of CIC patients required opioid escalation to patient-controlled analgesia (7% vs. 2%, P = .002). The CIC cohort experienced a greater length of stay (2.3 days vs. 2.1 days, P = .01) and more 30-day emergency department visits (5% vs. 2%, P = .038). CONCLUSIONS: LB demonstrated lower mean pain scores at 24 and 36 hours postoperatively and lower rates of severe postoperative pain. Additionally, LB patients showed significantly higher rates of opioid-free pain regimens. These results suggest that as part of a multimodal pain regimen in primary shoulder arthroplasty, LB may provide greater reductions in pain and opioid use when compared with CICs.

Perioperative Pain Management for Elective Spine Surgery: Opioid Use and Multimodal Strategies.

In recent years, physicians and institutions have come to recognize the increasing opioid epidemic in the United States, thus prompting a dramatic shift in opioid prescribing patterns. The lack of well-studied alternative treatment regimens has led to a substantial burden of opioid addiction in the United States. These forces have led to a huge economic burden on the country. The spine surgery population is particularly high risk for uncontrolled perioperative pain, because most patients experience chronic pain preoperatively and many patients continue to experience pain postoperatively. Overall, there is a large incentive to better understand comprehensive multimodal pain management regimens, particularly in the spine surgery patient population. The goal of this review is to explore trends in pain symptoms in spine surgery patients, overview the best practices in pain medications and management, and provide a concise multimodal and behavioral treatment algorithm for pain management, which has since been adopted by a high-volume tertiary academic medical center.

Clinical Outcomes After Stage-One Antibiotic Coated Molded Hip Spacer.

BACKGROUND: Two-stage exchange remains the gold standard for managing periprosthetic joint infection (PJI). We evaluated the outcomes of patients treated with a specific molded articulating antibiotic hip spacer for PJI at a tertiary referral center. METHODS: An institutional database was retrospectively queried for patients who underwent implantation of spacer between 2009-2019. Patient demographics and clinical outcomes were collected. RESULTS: We identified 88 patients at an average age of 60.4 years who received a spacer implant, with an average of 4.2 years follow-up (standard deviation [SD] 2.5 years). A total of 34 patients (38.6%) had a "clean" two-stage course with successful reimplantation and no evidence of infection at 1-year follow-up. The remaining patients (61.4%) required 3.67 (±0.52) additional surgeries. Overall reimplantation rate was 72%. Causative bacterial agents included MSSA (n = 22), MRSA (n = 16), coagulase-negative Staphylococcus (n = 14), and polymicrobial (n = 12). Regarding complications, there were 13 (15%) dislocations, 16 (18%) periprosthetic fractures, 8 (9%) bent/fractured stems, and 16 (18%) patients had clinically significant subsidence. Patients with previous extended trochanteric osteotomy (ETO) experienced higher rates of bent/broken spacer stems (25% vs 3.1%; P = .006) periprosthetic fractures (37.5% vs 10.9%; P = .010), and dislocations (37.5% vs 6.2%; P = .001). The rate of infection clearance was lower in the prior ETO cohort (26.6% vs 54.2%; P = .029). CONCLUSION: We report outcomes in patients who underwent implantation of a specific molded articulating hip spacer at our institution. Infection eradication was roughly in line with published series of hip PJI treatment. There was a high rate of mechanical complications, especially in those patients who required an ETO.

An analysis of 90-day emergency department visits after peripherally inserted central catheter (PICC) placement for prosthetic joint infection.

OBJECTIVE: Research on complications with peripherally inserted central catheter (PICC) lines that are placed for the treatment of prosthetic joint infection (PJI) after total hip arthroplasty (THA) and total knee arthroplasty (TKA) is scarce. We investigated the timing, frequency, and risk factors for PICC complications during treatment of PJI after THA and TKA. METHODS: We retrospectively queried an institutional database for THA and TKA patients from January 2015 through December 2020 that developed a PJI and required PICC placement at an academic, tertiary-care referral center. RESULTS: The study included 889 patients (48.3% female) with a mean age of 64.6 years (range, 18.7-95.2) who underwent 435 THAs and 454 TKAs that were revised for PJI. The cohort had 275 90-day ED visits (30.9%), and 51 (18.5%) were PICC related. The average time from discharge to PICC ED visit was 26.2 days (range, 0.3-89.4). The most common reasons for a 90-day ED visit were issues related to the joint replacement or wound site (musculoskeletal or MSK; n = 116, 42.2%) and PICC complaints (n = 51, 18.5%). A multivariable logistic regression demonstrated that non-White race (odds ratio [OR], 2.24; 95% confidence interval [CI], 1.24-4.04; P = .007) and younger age (OR, 0.98; 95% CI, 0.95-1.00; P = .035) were associated with PICC-related ED visits. Malposition/readjustment (41.2%) and occlusion (35.3%) were the most common PICC complications leading to ED presentation. CONCLUSIONS: PICC complications are common after PJI treatment, accounting for nearly 20% of 90-day ED visits.

Relative Value Units Underestimate Reimbursement for Revision Shoulder Arthroplasty.

INTRODUCTION: Relative value units (RVUs) have been fundamental to reimbursement calculations in payment models for arthroplasty surgeons. RVUs are based on various factors, including physician work, and have been higher for increased complexity, such as revision arthroplasty. The purpose of this study was to compare RVUs and estimated reimbursement differences between primary and revision shoulder arthroplasty. METHODS: The National Surgical Quality Improvement Program database was used to collect primary and revision shoulder arthroplasty cases in 2017. Data variables collected included age at the time of surgery, surgical time, and RVU for each shoulder arthroplasty. RESULTS: A total of 4,948 shoulder arthroplasty patients (4,657 primary and 291 revision) were included in this study. The mean age was 69.1 years (9.6 SD) for primary shoulder arthroplasty and 67.8 years (10.4 SD) for revision shoulder arthroplasty, P = 0.02. RVU for primary shoulder arthroplasty was 22.1 (0 SD) compared with 26.4 (1.1 SD) for revision shoulder arthroplasty (P = 0.0001). Surgical time was significantly higher in revision versus primary cases, 131.5 minutes (89.0 SD) versus 109.3 minutes (42.5 SD) (P = 0.0001). RVUs per minute were near equivalent for primary and revision arthroplasty at 0.20 (0.1 SD) and 0.20 (01 SD), respectively. However, owing to the difference in surgical time and cases per day, this translates to an estimated reimbursement difference of $174,554.4 per year more for primary shoulder arthroplasty over revision cases. CONCLUSION: The current RVU model does not adequately factor surgical time for revision shoulder arthroplasty and translates to a notable yearly reimbursement difference that favors primary shoulder arthroplasty.

Prosthetic Knee Infection With Coagulase-Negative Staphylococcus: A Harbinger of Poor Outcomes.

BACKGROUND: Coagulase-negative staphylococci (CoNS) are biofilm-producing pathogens whose role in periprosthetic joint infection (PJI) is increasing. There is little data on the prognosis and treatment considerations in the setting of PJI. We sought to evaluate the clinical characteristics, outcomes, and complications in these patients. METHODS: This is a retrospective cohort study of adult patients at a single tertiary medical center from 2009 to 2020 with culture-proven CoNS PJI after total knee arthroplasty, as diagnosed by Musculoskeletal Infection Society criteria. The primary outcome was treatment success, with failure defined as recurrent CoNS PJI, recurrent PJI with a new pathogen, and/or chronic oral antibiotic suppression at one year postoperatively. RESULTS: We identified 55 patients with a CoNS total knee arthroplasty PJI with a mean follow-up of 29.8 months (SD: 16.3 months). The most commonly isolated organism was Staphylococcus epidermidis (n = 36, 65.5%). The overall prevalence of methicillin resistance was 63%. Surgical treatment included surgical debridement, antibiotics, and implant retention in 25 (45.5%) cases and two-stage revision (22 articulating and eight static antibiotic-impregnated spacers). At one-year follow-up, only 47% of patients had successful management of their infection. The surgical debridement, antibiotics, and implant retention cohort had the higher rate of treatment failure (60.0%) compared to two-stage revision (46.7%). CONCLUSION: These results indicate a poor rate of success in treating CoNS PJI. This likely represents the interplay of inherent virulence through biofilm formation and decreased antibiotic efficacy.

Palliative Care Consultations in Patients with Severe Traumatic Brain Injury: Who Receives Palliative Care Consultations and What Does that Mean for Utilization?

BACKGROUND: Palliative care has the potential to improve goal-concordant care in severe traumatic brain injury (sTBI). Our primary objective was to illuminate the demographic profiles of patients with sTBI who receive palliative care encounters (PCEs), with an emphasis on the role of race. Secondary objectives were to analyze PCE usage over time and compare health care resource utilization between patients with or without PCEs. METHODS: The National Inpatient Sample database was queried for patients age ≥ 18 who had a diagnosis of sTBI, defined by using International Classification of Diseases, 9th Revision codes. PCEs were defined by using International Classification of Diseases, 9th Revision code V66.7 and trended from 2001 to 2015. To assess factors associated with PCE in patients with sTBI, we performed unweighted generalized estimating equations regression. PCE association with decision making was modeled via its effect on rate of percutaneous endoscopic gastrostomy (PEG) tube placement. To quantify differences in PCE-related decisions by race, race was modeled as an effect modifier. RESULTS: From 2001 to 2015, the proportion of palliative care usage in patients with sTBI increased from 1.5 to 36.3%, with 41.6% White, 22.3% Black, and 25% Hispanic patients with sTBI having a palliative care consultation in 2015, respectively. From 2008 to 2015, we identified 17,673 sTBI admissions. White and affluent patients were more likely to have a PCE than Black, Hispanic, and low socioeconomic status patients. Across all races, patients receiving a PCE resulted in a lower rate of PEG tube placement; however, White patients exhibited a larger reduction of PEG tube placement than Black patients. Patients using palliative care had lower total hospital costs (median $16,368 vs. $26,442, respectively). CONCLUSIONS: Palliative care usage for sTBI has increased dramatically this century and it reduces resource utilization. This is true across races, however, its usage rate and associated effect on decision making are race-dependent, with White patients receiving more PCE and being more likely to decline the use of a PEG tube if they have had a PCE.

Short-Stay Arthroplasty is Not Associated With Increased Risk of 90-Day Hospital Returns.

BACKGROUND: With the removal of total hip arthroplasty (THA) and total knee arthroplasty (TKA) from the inpatient-only list, medical centers are faced with challenging transitions to outpatient surgery. We investigated if short-stay arthroplasty, defined as length of stay (LOS) <24 hours, would influence 90-day readmissions and emergency department (ED) visits at a tertiary referral center. METHODS: The institutional database was retrospectively queried for primary TKAs and THAs from July 2015 to January 2018, resulting in 2,217 patients (1,361 TKA and 856 THA). Patient demographics, including age, gender, body mass index, and American Society of Anesthesiologists score were collected. LOS, disposition, cost of care, 90-day ED visits, and readmissions were identified through the institutional database using electronic medical record data. Univariable and multivariable models were used to evaluate rates of 90-day readmissions and ED visits based on LOS <24 hours vs ≥24 hours. RESULTS: LOS <24 h was associated with significant decreases in 90-day ED visits (P = .003) and readmissions (P = .002). After controlling for potential confounding variables with a multivariable model, a significant decrease in ED visits (P = .034) remained in the THA cohort alone. Within TKA and THA cohorts, LOS <24 h was associated with lower costs (P < .001). Eighteen percent of patients with ≥24 h LOS were discharged to skilled nursing or rehabilitation facilities. CONCLUSION: In this cohort, LOS <24 hours was associated with decreased 90-day readmissions, ED visits, and costs. With the goal of minimizing costs and maintaining patient safety while efficiently using resources, outpatient and short-stay arthroplasty are valuable, feasible options in tertiary academic centers.

A high-resolution interactive atlas of the human brainstem using magnetic resonance imaging.

Conventional atlases of the human brainstem are limited by the inflexible, sparsely-sampled, two-dimensional nature of histology, or the low spatial resolution of conventional magnetic resonance imaging (MRI). Postmortem high-resolution MRI circumvents the challenges associated with both modalities. A single human brainstem specimen extending from the rostral diencephalon through the caudal medulla was prepared for imaging after the brain was removed from a 65-year-old male within 24 h of death. The specimen was formalin-fixed for two weeks, then rehydrated and placed in a custom-made MRI compatible tube and immersed in liquid fluorocarbon. MRI was performed in a 7-Tesla scanner with 120 unique diffusion directions. Acquisition time for anatomic and diffusion images were 14 h and 208 h, respectively. Segmentation was performed manually. Deterministic fiber tractography was done using strategically chosen regions of interest and avoidance, with manual editing using expert knowledge of human neuroanatomy. Anatomic and diffusion images were rendered with isotropic resolutions of 50 µm and 200 µm, respectively. Ninety different structures were segmented and labeled, and 11 different fiber bundles were rendered with tractography. The complete atlas is available online for interactive use at https://www.civmvoxport.vm.duke.edu/voxbase/login.php?return_url=%2Fvoxbase%2F. This atlas presents multiple contrasting datasets and selected tract reconstruction with unprecedented resolution for MR imaging of the human brainstem. There are immediate applications in neuroanatomical education, with the potential to serve future applications for neuroanatomical research and enhanced neurosurgical planning through "safe" zones of entry into the human brainstem.

Outcomes and Health Care Resource Utilization of Adult Bacterial Meningitis in the United States.

OBJECTIVE: To examine the longitudinal health care resource utilization, in-hospital mortality, and incidence of downstream complications of bacterial meningitis in the United States. METHODS: Using IBM MarketScan, we retrieved data on adult patients with a diagnosis of bacterial meningitis admitted to a US hospital between 2008 and 2015. Patients were stratified into groups (1) with/without prior head trauma/neurosurgical complications, (2) nosocomial/community acquisition, and (3) Gram-negative/positive bacteria. Cost data were collected for up to 2 years and analyzed with descriptive statistics and longitudinal modeling. RESULTS: Among 4,496 patients with bacterial meningitis, 16.5% and 4.6% had preceding neurosurgical complications and head injuries, respectively. Lumbar punctures were performed in 37.3% of patients without prior trauma/complications who went on to develop nosocomial meningitis, and those with prior head injuries or complications had longer initial hospital stays (17.0 days vs 8.0 days). Within a month of diagnosis, 29.2% of patients with bacterial meningitis had experienced downstream complications, most commonly hydrocephalus (12.7%). The worst 30-day mortality was due to tuberculous (12.3%) and streptococcal meningitis (7.2%). Overall, prior head trauma and complications were associated with higher costs. Community-acquired bacterial meningitis had lower median baseline costs relative to the nosocomial group (no head trauma/complication: $17,152 vs $82,778; head trauma/complication: $92,428 vs $168,309) but higher median costs within 3 months of diagnosis (no head trauma/complication: $47,911 vs $34,202; head trauma/complication: $89,207 vs $58,947). All costs demonstrated a sharp decline thereafter. CONCLUSIONS: Bacterial meningitis remains costly and devastating, especially for those who experience traumatic head injuries or have a complicated progress after neurosurgery.

Inpatient mortality and healthcare resource utilization of nontraumatic intracerebral hemorrhage complications in the US.

OBJECTIVE: Nontraumatic, primary intracerebral hemorrhage (ICH) accounts for 2 million strokes worldwide annually and has a 1-year survival rate of 50%. Recent studies examining functional outcomes from ICH evacuation have been performed, but limited work has been done quantifying the incidence of subsequent complications and their healthcare economic impact. The purpose of this study was to quantify the incidence and healthcare resource utilization (HCRU) for major complications that can arise from ICH. METHODS: The IBM MarketScan Research databases were used to retrospectively identify patients with ICH from 2010 to 2015. Complications examined included cerebral edema, hydrocephalus, venous thromboembolic events (VTEs), pneumonia, urinary tract infections (UTIs), and seizures. For each complication, inpatient mortality and HCRU were assessed. RESULTS: Of 25,322 adult patients included, 10,619 (42%) developed complications during the initial admission of ICH: 22% had cerebral edema, 11% hydrocephalus, 10% pneumonia, 6% UTIs, 5% seizures, and 5% VTEs. The inpatient mortality rates at 7 and 30 days for each complication of ICH ranked from highest to lowest were hydrocephalus (24% and 32%), cerebral edema (15% and 20%), pneumonia (8% and 18%), seizure (7% and 13%), VTE (4% and 11%), and UTI (4% and 8%). Hydrocephalus had the highest total cost (median $92,776, IQR $39,308-$180,716) at 7 days post-ICH diagnosis and the highest cumulative total cost (median $170,839, IQR $91,462-$330,673) at 1 year post-ICH diagnosis. CONCLUSIONS: This study characterizes one of the largest cohorts of patients with nontraumatic ICH in the US. More than 42% of the patients with ICH developed complications during initial admission, which resulted in high inpatient mortality and considerable HCRU.

Paediatric bacterial meningitis in the USA: outcomes and healthcare resource utilization of nosocomial versus community-acquired infection.

Introduction. Paediatric bacterial meningitis remains a costly disease, both financially and clinically.Hypothesis/Gap Statement. Previous epidemiological and cost studies of bacterial meningitis (BM) have largely focused on adult populations or single pathogens. There have been few recent, large-scale studies of pediatric BM in the USA.Aim. We examined healthcare resource utilization (HCRU) and associated morbidity and mortality of community-acquired versus nosocomial bacterial infections in children across the USA.Methodology. The IBM MarketScan Research databases were used to identify patients <18 years old admitted to USA hospitals from 2008 to 2015 with a primary diagnosis of BM. Cases were categorized as either community-acquired or nosocomial. HCRU, post-diagnosis neurosurgical procedures, 30-day in-hospital mortality, and complications were compared between groups. Multivariable regression adjusted for sex, age and Gram staining was used to compare costs of nosocomial versus community-acquired infections over time.Results. We identified 1928 cases of paediatric BM without prior head trauma or neurological/systemic complications. Of these, 15.4 % were nosocomial and 84.6 % were community-acquired infections. After diagnostic lumbar puncture (37.1 %), the most common neurosurgical procedure was placement of ventricular catheter (12.6 %). The 30-day complication rates for nosocomial and community-acquired infections were 40.5 and 45.9 %, respectively. The most common complications were hydrocephalus (20.8 %), intracranial abscess (8.8 %) and cerebral oedema (8.1 %). The 30-day in-hospital mortality rates for nosocomial and community-acquired infections were 2.7 and 2.8 %, respectively.Median length of admission was 14.0 days (Q1: 7 days, Q3: 26 days). Median 90-day cost was $40 861 (Q1: $11 988, Q3: $114,499) for the nosocomial group and $56 569 (Q1: $26 127, Q3: $142 780) for the community-acquired group. In multivariable regression, the 90-day post-diagnosis total costs were comparable between groups (cost ratio: 0.89; 95 % CI: 0.70 to 1.13), but at 2 years post-diagnosis, the nosocomial group was associated with 137 % higher costs (CR: 2.37, 95 % CI: 1.51 to 3.70).Conclusion. In multivariable analysis, nosocomial infections were associated with significantly higher long-term costs up to 2 years post-infection. Hydrocephalus, intracranial epidural abscess and cerebral oedema were the most common complications, and lumbar punctures and ventricular catheter placement were the most common neurosurgical procedures. This study represents the first nation-wide, longitudinal comparison of the outcomes and considerable HCRU of nosocomial versus community-acquired paediatric BM, including characterization of complications and procedures contributing to the high costs of these infections.

Health care resource utilization and treatment of leptomeningeal carcinomatosis in the United States.

BACKGROUND: The economic burden of cancer in the United States is substantial, and better understanding it is essential in informing health care policy and innovation. Leptomeningeal carcinomatosis (LC) represents a late complication of primary cancer spreading to the leptomeninges. METHODS: The IBM MarketScan Research databases were queried for adults diagnosed with LC from 2001 to 2015, secondary to 4 primary cancers (breast, lung, gastrointestinal, and melanoma). Health care resource utilization (HCRU) and treatment utilization were quantified at baseline (1-year pre-LC diagnosis) and 30, 90, and 365 days post-LC diagnosis. RESULTS: We identified 4961 cases of LC (46.3% breast cancer, 34.8% lung cancer, 13.5% gastrointestinal cancer, and 5.4% melanoma). The median age was 57.0 years, with 69.7% female and 31.1% residing in the South. Insurance status included commercial (71.1%), Medicare (19.8%), and Medicaid (9.1%). Median follow-up was 66.0 days (25th percentile: 24.0, 75th percentile: 186.0) and total cumulative costs were highest for the gastrointestinal subgroup ($167 768) and lowest for the lung cancer subgroup ($145 244). There was considerable variation in the 89.6% of patients who used adjunctive treatments at 1 year, including chemotherapy (64.3%), radiotherapy (57.6%), therapeutic lumbar puncture (31.5%), and Ommaya reservoir (14.5%). The main cost drivers at 1 year were chemotherapy ($62 026), radiation therapy ($37 076), and specialty drugs ($29 330). The prevalence of neurologic impairments was 46.9%, including radiculopathy (15.0%), paresthesia (12.3%), seizure episode/convulsive disorder not otherwise specified (11.0%), and ataxia (8.0%). CONCLUSIONS: LC is a devastating condition with an overall poor prognosis. We present the largest study of LC in this real-world study, including current treatments, with an emphasis on HCRU. There is considerable variation in the treatment of LC and significant health care costs.

Impact of Spinal Cord Stimulation on Opioid Dose Reduction: A Nationwide Analysis.

BACKGROUND: Opioid misuse in the USA is an epidemic. Utilization of neuromodulation for refractory chronic pain may reduce opioid-related morbidity and mortality, and associated economic costs. OBJECTIVE: To assess the impact of spinal cord stimulation (SCS) on opioid dose reduction. METHODS: The IBM MarketScan® database was retrospectively queried for all US patients with a chronic pain diagnosis undergoing SCS between 2010 and 2015. Opioid usage before and after the procedure was quantified as morphine milligram equivalents (MME). RESULTS: A total of 8497 adult patients undergoing SCS were included. Within 1 yr of the procedure, 60.4% had some reduction in their opioid use, 34.2% moved to a clinically important lower dosage group, and 17.0% weaned off opioids entirely. The proportion of patients who completely weaned off opioids increased with decreasing preprocedure dose, ranging from 5.1% in the >90 MME group to 34.2% in the ≤20 MME group. The following variables were associated with reduced odds of weaning off opioids post procedure: long-term opioid use (odds ratio [OR]: 0.26; 95% CI: 0.21-0.30; P < .001), use of other pain medications (OR: 0.75; 95% CI: 0.65-0.87; P < .001), and obesity (OR: 0.75; 95% CI: 0.60-0.94; P = .01). CONCLUSION: Patients undergoing SCS were able to reduce opioid usage. Given the potential to reduce the risks of long-term opioid therapy, this study lays the groundwork for efforts that may ultimately push stakeholders to reduce payment and policy barriers to SCS as part of an evidence-based, patient-centered approach to nonopioid solutions for chronic pain.