Establishment of a model to predict mortality after decompression craniotomy for traumatic brain injury.

BACKGROUND: The mortality rate of patients with traumatic brain injury (TBI) is still high even while undergoing decompressive craniectomy (DC), and the expensive treatment costs bring huge economic burden to the families of patients. OBJECTIVE: The aim of this study was to identify preoperative indicators that influence patient outcomes and to develop a risk model for predicting patient mortality by a retrospective analysis of TBI patients undergoing DC. METHODS: A total of 288 TBI patients treated with DC, admitted to the First Affiliated Hospital of Shantou University Medical School from August 2015 to April 2021, were used for univariate and multivariate logistic regression analysis to determine the risk factors for death after DC in TBI patients. We also built a risk model for the identified risk factors and conducted internal verification and model evaluation. RESULTS: Univariate and multivariate logistic regression analysis identified four risk factors: Glasgow Coma Scale, age, activated partial thrombin time, and mean CT value of the superior sagittal sinus. These risk factors can be obtained before DC. In addition, we also developed a 3-month mortality risk model and conducted a bootstrap 1000 resampling internal validation, with C-indices of 0.852 and 0.845, respectively. CONCLUSIONS: We developed a risk model that has clinical significance for the early identification of patients who will still die after DC. Interestingly, we also identified a new early risk factor for TBI patients after DC, that is, preoperative mean CT value of the superior sagittal sinus (p < .05).

Endoscopic trans-anal tube placement is a safe and helpful tool for colonic decompression: final results of a standardized single-centre retrospective assessment of 125 patients.

OBJECTIVES: Endoscopic trans-anal colonic decompression (ECD) may be requested in the case of massive colon distension, but evidence regarding success and safety issues remains scarce. The aim of this analysis is to examine the technical success, complications and clinical outcome in a large series of patients undergoing an ECD in various clinical scenarios. A standardized evaluation system was used to identify the pre-interventional risk parameters that might be helpful to guide clinical decision making. METHODS: In this single-centre retrospective study, the modified Clavien-Dindo classification (CDC) was applied to assess technical success, complications and clinical outcome of 125 consecutive patients who underwent ECD between 2007 and 2020. PRIMARY ENDPOINT: post interventional 90-day mortality. Secondary endpoints: periprocedural complications (CDC event IV-V) and technical success rate. All Martin criteria for standardized reporting of complications were met. Uni- and multivariable analyses for prediction of complications were carried out. RESULTS: The overall technical success rate was 90%. The periprocedural complication rate was low with 3%. Overall 90-day mortality was 31%. Univariable analyses showed a significant correlation between 90-day mortality and ASA≥4 (p<0.001, odds ratio [OR] 15.33), general anaesthesia (p=0.05, OR 21.42) and elevated serological infection parameters (p 0.028, OR 1.004). The pre-interventional multivariable model identified ASA ≥4 (p <0.001; OR 10.94) as the only independent risk factor. CONCLUSIONS: ECD is a safe, easily available, technical feasible, inexpensive and successful tool for colonic decompression in various colonic obstruction scenarios, even in critically ill patients. ASA Score ≥IV can be helpful to identify patients at risk for complications/mortality after ECD.

Patient and physician radiation exposure during minimally invasive lumbar decompression: A prospective assessment of X-ray exposure risks.

INTRODUCTION: Minimally invasive lumbar decompression (mild®) is becoming a popular procedure for treating lumbar spinal stenosis (LSS) secondary to hypertrophic ligamentum flavum (LF). The mild® procedure is commonly performed under live fluoroscopic guidance and carries a risk of radiation exposure to the patient and healthcare. METHODS: One physician performed mild® on 41 patients at the Cleveland Clinic Department of Pain Management from October 2019 to December 2021, while wearing a radiation exposure monitor (Mirion Technologies). Mean fluoroscopy time, mean exposure per case, and mean exposure per unilateral level decompressed were the primary outcomes measured. The secondary outcome was to provide a comparison of radiation exposure during similar fluoroscopically guided procedures. RESULTS: Mean patient fluoroscopy exposure time was 2.1 min ±0.9 (range: 1.1-5.6) fluoroscopy time per unilateral level decompressed. The mean patient radiation skin exposure from mild® was 1.1 ± 0.9 mGym2, and the mean total dose was 142.3 ± 108.6 mGy per procedure. On average, the physician was exposed to an average deep tissue exposure of 4.1 ± 3.2 mRem, 2.9 ± 2.2 mRem estimated eye exposure, and 14.7 ± 11.0 mRem shallow tissue exposure per unilateral level decompressed. An individual physician would exceed the annual exposure limit of 5 Rem after approximately 610 mild® procedures per year. CONCLUSIONS: This study is an attempt to quantify the radiation exposure to the physician and patient during the mild® procedure. Compared with other fluoroscopically guided pain management procedures, patient and physician radiation exposure during mild® was low.

Chronic cauda equina syndrome decompression surgery recovery is very "bad"? Based on patient self-assessment.

BACKGROUND: Symptoms of cauda equina syndrome (CES) secondary to degenerative lumbar spine diseases are sometimes mild and tend to be ignored by patients, resulting in delayed treatment. In addition, the long-term efficacy of surgery is unclear. OBJECTIVE: To determine the predictive factors of CES and post-operative recovery in patients with symptoms lasting > 3 months. METHODS: From January 2011 to December 2020, data of 45 patients with CES secondary to lumbar disk herniation/lumbar spinal stenosis were collected from a single center. The patients had bladder, bowel or sexual dysfunction and decreased perineal sensation that lasted for > 3 months. A 2-year post-operative follow-up was conducted to evaluate recovery outcomes, which were measured by validated self-assessment questionnaires conducted by telephone and online. RESULTS: Overall, 45 CES patients (57.8% female; mean age, 56 years) were included. The duration of pre-operative CES symptoms was 79.6 weeks (range, 13-730 weeks). The incidence of saddle anesthesia before decompression was 71.1% (n = 32), bladder dysfunction 84.4% (n = 38), bowel dysfunction 62.2% (n = 28) and sexual dysfunction 64.4% (n = 29). The overall recovery rate of CES after a 2-year follow-up was 64.4%. The rates of the residual symptoms at the last follow-up were as follows: saddle anesthesia 22.2%, bladder dysfunction 33.3%, bowel dysfunction 24.4% and sexual dysfunction 48.9%. Pre-operative saddle anesthesia, overactive bladder and sexual dysfunction were risk factors for poor prognosis after decompression. CONCLUSION: CES patients with symptoms lasting > 3 months may recover after surgery. Sexual dysfunction has a high residual rate and should not be ignored during diagnosis and treatment.

Risk assessment of SWEN21 a suggested new dive table for the Swedish armed forces: bubble grades by ultrasonography.

Introduction: To develop the diving capacity in the Swedish armed forces the current air decompression tables are under revision. A new decompression table named SWEN21 has been created to have a projected risk level of 1% for decompression sickness (DCS) at the no stop limits. The aim of this study was to evaluate the safety of SWEN21 through the measurement of venous gas emboli (VGE) in a dive series. Methods: A total 154 dives were conducted by 47 divers in a hyperbaric wet chamber. As a proxy for DCS risk serial VGE measurements by echocardiography were conducted and graded according to the Eftedal-Brubakk scale. Measurements were done every 15 minutes for approximately 2 hours after each dive. Peak VGE grades for the different dive profiles were used in a Bayesian approach correlating VGE grade and risk of DCS. Symptoms of DCS were continually monitored. Results: The median (interquartile range) peak VGE grade after limb flexion for a majority of the time-depth combinations, and of SWEN21 as a whole, was 3 (3-4) with the exception of two decompression profiles which resulted in a grade of 3.5 (3-4) and 4 (4-4) respectively. The estimated risk of DCS in the Bayesian model varied between 4.7-11.1%. Three dives (2%) resulted in DCS. All symptoms resolved with hyperbaric oxygen treatment. Conclusions: This evaluation of the SWEN21 decompression table, using bubble formation measured with echocardiography, suggests that the risk of DCS may be higher than the projected 1%.

Patterns in Decompression and Fusion Procedures for Patients With Lumbar Stenosis After Major Clinical Trial Results, 2016 to 2019.

Importance: Use of lumbar fusion has increased substantially over the last 2 decades. For patients with lumbar stenosis and degenerative spondylolisthesis, 2 landmark prospective randomized clinical trials (RCTs) published in the New England Journal of Medicine in 2016 did not find clear evidence in favor of decompression with fusion over decompression alone in this population. Objective: To assess the national use of decompression with fusion vs decompression alone for the surgical treatment of lumbar stenosis and degenerative spondylolisthesis from 2016 to 2019. Design, Setting, and Participants: This retrospective cohort study included 121 745 hospitalized adult patients (aged ≥18 years) undergoing 1-level decompression alone or decompression with fusion for the management of lumbar stenosis and degenerative spondylolisthesis from January 1, 2016, to December 31, 2019. All data were obtained from the National Inpatient Sample (NIS). Analyses were conducted, reviewed, or updated on June 9, 2023. Main Outcome and Measure: The primary outcome of this study was the use of decompression with fusion vs decompression alone. For the secondary outcome, multivariable logistic regression analysis was used to evaluate factors associated with the decision to perform decompression with fusion vs decompression alone. Results: Among 121 745 eligible hospitalized patients (mean age, 65.2 years [95% CI, 65.0-65.4 years]; 96 645 of 117 640 [82.2%] non-Hispanic White) with lumbar stenosis and degenerative spondylolisthesis, 21 230 (17.4%) underwent decompression alone, and 100 515 (82.6%) underwent decompression with fusion. The proportion of patients undergoing decompression alone decreased from 2016 (7625 of 23 405 [32.6%]) to 2019 (3560 of 37 215 [9.6%]), whereas the proportion of patients undergoing decompression with fusion increased over the same period (from 15 780 of 23 405 [67.4%] in 2016 to 33 655 of 37 215 [90.4%] in 2019). In univariable analysis, patients undergoing decompression alone differed significantly from those undergoing decompression with fusion with regard to age (mean, 68.6 years [95% CI, 68.2-68.9 years] vs 64.5 years [95% CI, 64.3-64.7 years]; P < .001), insurance status (eg, Medicare: 13 725 of 21 205 [64.7%] vs 53 320 of 100 420 [53.1%]; P < .001), All Patient Refined Diagnosis Related Group risk of death (eg, minor risk: 16 900 [79.6%] vs 83 730 [83.3%]; P < .001), and hospital region of the country (eg, South: 7030 [33.1%] vs 38 905 [38.7%]; Midwest: 4470 [21.1%] vs 23 360 [23.2%]; P < .001 for both comparisons). In multivariable logistic regression analysis, older age (adjusted odds ratio [AOR], 0.96 per year; 95% CI, 0.95-0.96 per year), year after 2016 (AOR, 1.76 per year; 95% CI, 1.69-1.85 per year), self-pay insurance status (AOR, 0.59; 95% CI, 0.36-0.95), medium hospital size (AOR, 0.77; 95% CI, 0.67-0.89), large hospital size (AOR, 0.76; 95% CI, 0.67-0.86), and highest median income quartile by patient residence zip code (AOR, 0.79; 95% CI, 0.70-0.89) were associated with lower odds of undergoing decompression with fusion. Conversely, hospital region in the Midwest (AOR, 1.34; 95% CI, 1.14-1.57) or South (AOR, 1.32; 95% CI, 1.14-1.54) was associated with higher odds of undergoing decompression with fusion. Decompression with fusion vs decompression alone was associated with longer length of stay (mean, 2.96 days [95% CI, 2.92-3.01 days] vs 2.55 days [95% CI, 2.49-2.62 days]; P < .001), higher total admission costs (mean, $30 288 [95% CI, $29 386-$31 189] vs $16 190 [95% CI, $15 189-$17 191]; P < .001), and higher total admission charges (mean, $121 892 [95% CI, $119 566-$124 219] vs $82 197 [95% CI, $79 745-$84 648]; P < .001). Conclusions and Relevance: In this cohort study, despite 2 prospective RCTs that demonstrated the noninferiority of decompression alone compared with decompression with fusion, use of decompression with fusion relative to decompression alone increased from 2016 to 2019. A variety of patient- and hospital-level factors were associated with surgical procedure choice. These results suggest the findings of 2 major RCTs have not yet produced changes in surgical practice patterns and deserve renewed focus.

Incidence and management of postoperative pseudomeningocele and cerebrospinal fluid leak after Chiari malformation type I decompression.

OBJECTIVE: The optimal surgical management of Chiari malformation type I (CM-I) remains controversial and heterogeneous. The authors sought to investigate patient-specific, technical, and perioperative features that may affect the incidence of CSF-related complications including pseudomeningocele and CSF leak at their institution. METHODS: The authors performed a single-center, retrospective review of all adult patients with CM-I who underwent posterior fossa decompression. Patient demographics, operative details, and perioperative factors were collected via electronic medical record review. The authors performed Fisher's exact test and independent Student t-tests for categorical and continuous variables, respectively. Univariate regression analysis was performed to determine odds ratios. A multivariable regression analysis was performed for those factors with p < 0.10 or large effect sizes (OR ≥ 2.0 or ≤ 0.50) by univariate analysis. The STROBE guidelines for observational studies were followed. RESULTS: A total of 59 adult patients were included. Most patients were female (78.0%), and the mean body mass index was 32.2 (± 9.0). Almost one-third (30.5%) of patients had a syrinx on preoperative imaging. All patients underwent expansile duraplasty, of which 47 (79.7%) were from autologous pericranium. Arachnoid opening for fourth ventricular inspection was performed in 26 (44.1%) cases. CSF-related complications were identified in 18 (30.5%) of cases. Thirteen (22.0%) patients required readmission and 11 (18.6%) required intervention such as wound revision (n = 5), wound revision with CSF diversion (n = 4), CSF diversion alone (n = 1), or blood patch (n = 1). Three (5.1%) patients required permanent CSF diversion. Male sex (OR 3.495), diabetes mellitus (OR 0.249), tobacco use (OR 2.53), body mass index more than 30 (OR 2.45), preoperative syrinx (OR 1.733), autologous duraplasty (OR 0.331), and postoperative steroids (OR 2.825) were included in the multivariable analysis. No factors achieved significance by univariate or multivariable analysis (all p > 0.05). CONCLUSIONS: The authors report a single-center, retrospective experience of posterior fossa decompression for 59 adults with CM-I. No perioperative or technical features were found to affect the CSF-related complication rate. More standardized practices within centers are necessary to better delineate the true risk factors and potential protective factors against CSF-related complications.

A decision tree analysis to predict clinical outcome of minimally invasive lumbar decompression surgery for lumbar spinal stenosis with and without coexisting spondylolisthesis and scoliosis.

BACKGROUND CONTEXT: Implementing machine learning techniques, such as decision trees, known as prediction models that use logical construction diagrams, are rarely used to predict clinical outcomes. PURPOSE: To develop a clinical prediction rule to predict clinical outcomes in patients who undergo minimally invasive lumbar decompression surgery for lumbar spinal stenosis with and without coexisting spondylolisthesis and scoliosis using a decision tree model. STUDY DESIGN/SETTING: A retrospective analysis of prospectively collected data. PATIENT SAMPLE: This study included 331 patients who underwent minimally invasive surgery for lumbar spinal stenosis and were followed up for ≥2 years at 1 institution. OUTCOME MEASURES: Self-report measures: The Japanese Orthopedic Association (JOA) scores and low back pain (LBP)/leg pain/leg numbness visual analog scale (VAS) scores. Physiologic measures: Standing sagittal spinopelvic alignment, computed tomography, and magnetic resonance imaging results. METHODS: Low achievement in clinical outcomes were defined as the postoperative JOA score at the 2-year follow-up <25 points. Univariate and multiple logistic regression analysis and chi-square automatic interaction detection (CHAID) were used for analysis. RESULTS: The CHAID model for JOA score <25 points showed spontaneous numbness/pain as the first decision node. For the presence of spontaneous numbness/pain, sagittal vertical axis ≥70 mm was selected as the second decision node. Then lateral wedging, ≥6° and pelvic incidence minus lumbar lordosis (PI-LL) ≥30° followed as the third decision node. For the absence of spontaneous numbness/pain, sex and lateral olisthesis, ≥3mm and American Society of Anesthesiologists physical status classification system score were selected as the second and third decision nodes. The sensitivity, specificity, and the positive predictive value of this CHAID model was 65.1, 69.8, and 64.7% respectively. CONCLUSIONS: The CHAID model incorporating basic information and functional and radiologic factors is useful for predicting surgical outcomes.

Impact of Race/Ethnicity on Hospital Resource Utilization After Elective Anterior Cervical Decompression and Fusion for Degenerative Myelopathy.

INTRODUCTION: With the advent of bundled care payments for spine surgery, there is increasing scrutiny on the costs and resource utilization associated with surgical care. The purpose of this study was to compare (1) the total cost of the hospital episode of care and (2) discharge destination between White, Black, and Hispanic patients receiving elective anterior cervical decompression and fusion for degenerative cervical myelopathy (DCM) in Medicare patients. METHODS: The 2019 Medicare Provider Analysis and Review Limited Data Set and the 2019 Impact File were used for this project. Multivariate models were created for total cost and discharge destination, controlling for confounders found on univariate analysis. We then performed a subanalysis for differences in specific cost-center charges. RESULTS: There were 11,506 White (85.4%), 1,707 Black (12.7%), and 261 Hispanic (1.9%) patients identified. There were 6,447 males (47.8%) and 7,027 females (52.2%). Most patients were between 65 to 74 years of age (n = 7,101, 52.7%). The mean cost of the hospital episode was $20,919 ± 11,848. Most patients were discharged home (n = 11,584, 86.0%). Race/ethnicity was independently associated with an increased cost of care (Black: $783, Hispanic: $1,566, P = 0.001) and an increased likelihood of nonhome discharge (Black: adjusted odds ratio: 1.990, P < 0.001, Hispanic: adjusted odds ratio: 1.822, P < 0.001) compared with White patients. Compared with White patients, Black patients were charged more for accommodations ($1808), less for supplies (-$1780), and less for operating room (-$1072), whereas Hispanic patients were charged more ($3556, $7923, and $5162, respectively, P < 0.05). CONCLUSION: Black and Hispanic race/ethnicity were found to be independently associated with an increased cost of care and risk for nonhome discharge after elective anterior cervical decompression and fusion for DCM compared with White patients. The largest drivers of this disparity appear to be accommodation, medical/surgical supply, and operating room-related charges. Further analysis of these racial disparities should be performed to improve value and equity of spine care for DCM.

Assessment of foraminal decompression following discoplasty using a combination of ex vivo testing and numerical tools.

Percutaneous Cement Discoplasty (PCD) is a minimally invasive surgical technique to treat degenerated intervertebral discs. When the disc is severely degenerated, the vacuum observed in place of the nucleus pulposus can be filled with bone cement to restore the disc height, open the foramen space, and relieve pain. This study aimed to evaluate the foramen geometry change due to PCD, in the loaded spine. Cadaveric spines (n = 25) were tested in flexion and extension while Digital Image Correlation (DIC) measured displacements and deformations. Tests were performed on simulated pre-operative condition (nucleotomy) and after PCD. Registering DIC images and the 3D specimen geometry from CT scans, a 3D model of the specimens aligned in the experimental pose was obtained for nucleotomy and PCD. Foramen space volume was geometrically measured for both conditions. The volume of cement injected was measured to explore correlation with the change of foramen space. PCD induced a significant overall foraminal decompression in both flexion (foramen space increased by 835 ± 1289 mm3, p = 0.001) and extension (1205 ± 1106 mm3, p < 0.001), confirming that the expected improvements of PCD show also during spine motion. Furthermore, in extension when the foramen is the most challenged, the impact of PCD on the foramen correlated with the injected cement volume.

A cost-utility analysis between decompression only and fusion surgery for elderly patients with lumbar spinal stenosis and sagittal imbalance.

Lumbar spinal stenosis (LSS) and sagittal imbalance are relatively common in elderly patients. Although the goals of surgery include both functional and radiological improvements, the criteria of correction may be too strict for elderly patients. If the main symptom of patients is not forward-stooping but neurogenic claudication or pain, lumbar decompression without adding fusion procedure may be a surgical option. We performed cost-utility analysis between lumbar decompression and lumbar fusion surgery for those patients. Elderly patients (age > 60 years) who underwent 1-2 levels lumbar fusion surgery (F-group, n = 31) or decompression surgery (D-group, n = 40) for LSS with sagittal imbalance (C7 sagittal vertical axis, C7-SVA > 40 mm) with follow-up ≥ 2 years were included. Clinical outcomes (Euro-Quality of Life-5 Dimensions, EQ-5D; Oswestry Disability Index, ODI; numerical rating score of pain on the back and leg, NRS-B and NRS-L) and radiological parameters (C7-SVA; lumbar lordosis, LL; the difference between pelvic incidence and lumbar lordosis, PI-LL; pelvic tilt, PT) were assessed. The quality-adjusted life year (QALY) and incremental cost-effective ratio (ICER) were calculated from a utility score of EQ-5D. Postoperatively, both groups attained clinical and radiological improvement in all parameters, but NRS-L was more improved in the F-group (p = 0.048). ICER of F-group over D-group was 49,833 US dollars/QALY. Cost-effective lumbar decompression may be a recommendable surgical option for certain elderly patients, despite less improvement of leg pain than with fusion surgery.

Hyperbaric exposure in rodents with non-invasive imaging assessment of decompression bubbles: A scoping review protocol.

Hyperbaric pressure experiments have provided researchers with valuable insights into the effects of pressure changes, using various species as subjects. Notably, extensive work has been done to observe rodents subjected to hyperbaric pressure, with differing imaging modalities used as an analytical tool. Decompression puts subjects at a greater risk for injury, which often justifies conducting such experiments using animal models. Therefore, it is important to provide a broad view of previously utilized methods for decompression research to describe imaging tools available for researchers to conduct rodent decompression experiments, to prevent duplicate experimentation, and to identify significant gaps in the literature for future researchers. Through a scoping review of published literature, we will provide an overview of decompression bubble information collected from rodent experiments using various non-invasive methods of ultrasound for decompression bubble assessment. This review will adhere to methods outlined by the Joanna Briggs Institute Manual for Evidence Synthesis and be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews (PRISMA-ScR). Literature will be obtained from the PubMed, Embase, and Scopus databases. Extracted sources will first be sorted to a list for inclusion based on title and abstract. Two independent researchers will then conduct full-text screening to further refine included papers to those relevant to the scope. The final review manuscript will cover methods, data, and findings for each included publication relevant to non-invasive in vivo bubble imaging.

Implementation of Machine Learning to Predict Cost of Care Associated with Ambulatory Single-Level Lumbar Decompression.

BACKGROUND: With the emergence of the concept of value-based care, efficient resource allocation has become an increasingly prominent factor in surgical decision-making. Validated machine learning (ML) models for cost prediction in outpatient spine surgery are limited. As such, we developed and internally validated a supervised ML algorithm to reliably identify cost drivers associated with ambulatory single-level lumbar decompression surgery. METHODS: A retrospective review of the New York State Ambulatory Surgical Database was performed to identify patients who underwent single-level lumbar decompression from 2014 to 2015. Patients with a length of stay of >0 were excluded. Using pre- and intraoperative parameters (features) derived from the New York State Ambulatory Surgical Database, an optimal supervised ML model was ultimately developed and internally validated after 5 candidate models were rigorously tested, trained, and compared for predictive performance related to total charges. The best performing model was then evaluated by testing its performance on identifying relationships between features of interest and cost prediction. Finally, the best performing algorithm was entered into an open-access web application. RESULTS: A total of 8402 patients were included. The gradient-boosted ensemble model demonstrated the best performance assessed via internal validation. Major cost drivers included anesthesia type, operating room time, race, patient income and insurance status, community type, worker's compensation status, and comorbidity index. CONCLUSIONS: The gradient-boosted ensemble model predicted total charges and associated cost drivers associated with ambulatory single-level lumbar decompression using a large, statewide database with excellent performance. External validation of this algorithm in future studies may guide practical application of this clinical tool.

Obesity and Workers' Compensation in the Setting of Minimally Invasive Lumbar Decompression.

OBJECTIVE: To investigate the influence of body mass index (BMI) on perioperative outcomes, postoperative patient-reported outcome measures (PROMs), and minimal clinically important difference (MCID) achievement among workers' compensation (WC) claimants undergoing minimally invasive lumbar decompression (MIS-LD). METHODS: WC patients diagnosed with herniated nucleus pulposus undergoing single-level MIS-LD were identified. Patients were divided into 3 groups: Non-obese (<30 kg/m2), Obese I (≥30 and <35 kg/m2), and Obese II/III (≥35 kg/m2). PROMs were collected preoperatively and at 6 weeks, 12 weeks, 6 months, 1 year, and 2 years postoperatively. The predictive influence of BMI grouping on mean PROM scores was computed using simple linear regression. To compare PROMs between groups, post hoc pairwise comparisons of adjusted means were utilized. MCID achievement was compared between groups with χ2 analysis. RESULTS: A total of 81 patients were in the Non-obese cohort, and 43 and 45 in the Obese I and Obese II/III cohorts, respectively. Visual analog scale (VAS) leg, Oswestry Disability Index (ODI), and 12-Item Short Form Physical Composite Score (SF-12 PCS) were worse in the Obese I cohort at 12 weeks, and SF-12 PCS was lower in the Obese I vs. Obese II/III subgroup analysis (P ≤ 0.045, all). MCID achievement rates for ODI were higher for the Non-obese group at 12 weeks and overall (P ≤ 0.049, both). MCID attainment for VAS back was higher among the Non-obese cohort at 6-weeks (P = 0.022). CONCLUSIONS: Patients with higher levels of obesity were more likely to experience longer length of stay and delayed discharge following MIS-LD. Increasing BMI was generally not a significant predictor of postoperative pain, disability, or physical health PROMs at most timepoints. MCID achievement rates for disability relief were significantly higher for non-obese patients.

A safety assessment of a 300-meter saturation dive at sea by mental ability and performance efficacy.

High pressure is an environmental characteristic of the deep sea that may exert critical effects on the physiology and mental abilities of divers. In this study we evaluated the performance efficacy and mental ability of four divers during a 300-meter helium-oxygen saturation dive at sea. Spatial memory, 2D/3D mental rotation functioning, grip strength, and hand-eye coordination ability were examined for four divers during the pre-dive, compression, decompression, and post-dive phases. The results showed that both the reaction time and the correct responses for the mental rotation and hand-eye coordination were slightly fluctuated. In addition, there was a significant decline in the grip strength of the left hand. It is concluded that the performance efficacy and mental ability of divers were virtually unaffected during 300-meter helium-oxygen saturation diving at sea.

The Impact of American Society of Anesthesiologists Status on Cost of Care and Length of Stay Following Posterior Cervical Decompression and Fusion.

BACKGROUND: Increased posterior cervical decompression and fusion (PCDF) procedures over the past decade have raised the prospect of bundled payment plans. The American Society of Anesthesiologists (ASA) Physical Status Classification system may enable accurate estimation of health care costs, length of stay (LOS), and other postoperative outcomes in patients undergoing PCDF. METHODS: Low (I and II) versus high (III and IV) ASA class was used to evaluate 971 patients who underwent PCDF between 2008 and 2016 at a single institution. Demographics were compared using univariate analysis. Cost of care, LOS, and postoperative complications were compared using multivariable logistic and linear regression, controlling for sex, age, length of surgery, and number of segments fused. RESULTS: The high ASA class cohort was older (mean age 62 years vs. 55 years, P < 0.0001) and had higher Elixhauser comorbidity index scores (P < 0.0001). ASA class was independently associated with longer LOS (2.1 days, 95% confidence interval [CI] 1.3-2.9, P < 0.0001) and higher cost ($2936, 95% CI $1457-$4415, P < 0.0001). Patients with high ASA class were more likely to have a nonhome discharge (3.9, 95% CI 2.8-5.6, P < 0.0001), delayed extubation (3.2, 95% CI 1.4-7.3, P = 0.006), intensive care unit stay (2.4, 95% CI 1.5 3.7, P = 0.0001), in-hospital complications (1.5, 95% CI 1.0-2.2, P = 0.03), and 30-day (3.2, 95% CI 1.5-6.8, P = 0.003) and 90-day (3.2, 95% CI 1.8-5.7, P = 0.0001) readmission. CONCLUSIONS: High ASA class is strongly associated with increased costs, LOS, and adverse outcomes following PCDF and could be useful for preoperative prediction of these outcomes.

Do all outpatient spine surgeries cost the same? Comparison of economic outcomes data from a state-level database for outpatient lumbar decompression performed in an ambulatory surgery center or hospital outpatient setting.

OBJECTIVE: Spinal procedures are increasingly conducted as outpatient procedures, with a growing proportion conducted in ambulatory surgery centers (ASCs). To date, studies reporting outcomes and cost analyses for outpatient spinal procedures in the US have not distinguished the various outpatient settings from each other. In this study, the authors used a state-level administrative database to compare rates of overnight stays and nonroutine discharges as well as index admission charges and cumulative 7-, 30-, and 90-day charges for patients undergoing outpatient lumbar decompression in freestanding ASCs and hospital outpatient (HO) settings. METHODS: For this project, the authors used the Florida State Ambulatory Surgery Database (SASD), offered by the Healthcare Cost and Utilization Project (HCUP), for the years 2013 and 2014. Patients undergoing outpatient lumbar decompression for degenerative diseases were identified using CPT (Current Procedural Terminology) and ICD-9 codes. Outcomes of interest included rates of overnight stays, rate of nonroutine discharges, index admission charges, and subsequent admission cumulative charges at 7, 30, and 90 days. Multivariable analysis was performed to assess the impact of outpatient type on index admission charges. Marginal effect analysis was employed to study the difference in predicted dollar margins between ASCs and HOs for each insurance type. RESULTS: A total of 25,486 patients were identified; of these, 7067 patients (27.7%) underwent lumbar decompression in a freestanding ASC and 18,419 (72.3%) in an HO. No patient in the ASC group required an overnight stay compared to 9.2% (n = 1691) in the HO group (p < 0.001). No clinically significant difference in the rate of nonroutine discharge was observed between the two groups. The mean index admission charge for the ASC group was found to be significantly higher than that for the HO group ($35,017.28 ± $14,335.60 vs $33,881.50 ± $15,023.70; p < 0.001). Patients in ASCs were also found to have higher mean 7-day (p < 0.001), 30-day (p < 0.001), and 90-day (p = 0.001) readmission charges. ASC procedures were associated with increased charges compared to HO procedures for patients on Medicare or Medicaid (mean index admission charge increase $4049.27, 95% CI $2577.87-$5520.67, p < 0.001) and for patients on private insurance ($4775.72, 95% CI $4171.06-$5380.38, p < 0.001). For patients on self-pay or no charge, a lumbar decompression procedure at an ASC was associated with a decrease in index admission charge of -$10,995.38 (95% CI -$12124.76 to -$9866.01, p < 0.001) compared to a lumbar decompression procedure at an HO. CONCLUSIONS: These "real-world" results from an all-payer statewide database indicate that for outpatient spine surgery, ASCs may be associated with higher index admission and subsequent 7-, 30-, and 90-day charges. Given that ASCs are touted to have lower overall costs for patients and better profit margins for physicians, these analyses warrant further investigation into whether this cost benefit is applicable to outpatient spine procedures.

Do safety-net hospitals provide equitable care after decompressive surgery for acute cauda equina syndrome?

INTRODUCTION: Safety-net hospitals provide care to a substantial share of disadvantaged patient populations. Whether disparities exist between safety-net hospitals and their counterparts in performing emergent neurosurgical procedures has not yet been examined. OBJECTIVE: We used the Nationwide Inpatient Sample (NIS), a national all-payer inpatient healthcare database, to determine whether safety-net hospitals provide equitable care after decompressive surgery for acute cauda equina syndrome (CES). METHODS: The NIS from 2002 to 2011 was queried for patients with a diagnosis of acute CES who received decompressive surgery. Hospital safety-net burden was designated as low (LBH), medium (MBH), or high (HBH) based on the proportion of inpatient admissions that were billed as Medicaid, self-pay, or charity care. Etiologies of CES were classified as degenerative, neoplastic, trauma, and infectious. Significance was defined at p < 0.01. RESULTS: A total of 5607 admissions were included in this analysis. HBHs were more likely than LBHs to treat patients who were Black, Hispanic, on Medicaid, or had a traumatic CES etiology (p < 0.001). After adjusting for patient, hospital, and clinical factors treatment at an HBH was not associated with greater inpatient adverse events (p = 0.611) or LOS (p = 0.082), but was associated with greater inflation-adjusted admission cost (p = 0.001). DISCUSSION: Emergent decompressive surgery for CES performed at SNHs is associated with greater inpatient costs, but not greater inpatient adverse events or LOS. Differences in workflows at SNHs may be the drivers of these disparities in cost and warrant further investigation.

Primary single-level lumbar microdisectomy/decompression at a free-standing ambulatory surgical center vs a hospital-owned outpatient department-an analysis of 90-day outcomes and costs.

BACKGROUND CONTEXT: While free-standing ambulatory surgical centers (ASCs) have been extolled as lower cost settings than hospital outpatient facilities/departments (HOPDs) for performing routine elective spine surgeries, differences in 90-day costs and complications have yet to be compared between the two types of treatment facilities. PURPOSE: We carried a comprehensive analysis to report the differences on payments to providers and facilities as a reflection of true costs to patients, employers and health plans for patients undergoing primary, single-level lumbar microdiscectomy/decompression at ASC versus HOPD. STUDY DESIGN: Retrospective review of Medicare advantage and commercially insured enrollees from the Humana dataset from 2007 to 2017Q1. OUTCOME MEASURES: To understand the differences in 90-day complications, readmissions, emergency department visits and costs for patients undergoing primary, single-level lumbar microdiscectomy/decompressions at an ASC versus HOPD. METHODS: The Humana 2007 to 2017Q1 was queried using Current Procedural Terminology codes to identify patients undergoing primary, single-level lumbar microdiscectomy/decompressions. Patients undergoing two-level surgery, open laminectomies, fusions, revision discectomies, and/or deformities were excluded. Service Location codes for HOPD (Location Code 22) and free-standing ASC (Location Code 24) were used to determine surgery treatment facilities. Using propensity scoring, we matched two groups who had surgery performed in ASCs or HOPDs based on age, gender, race, region and Elixhauser comorbidity index. Multivariable logistic regression analyses were performed on matched cohorts to assess for differences in 90-day outcomes between facilities, while controlling for age, gender, race, region, plan, and Elixhauser comorbidity index. RESULTS: A total of 1,077 and 10,475 primary single-level decompressions were performed in ASCs and HOPDs, respectively. Following a matching algorithm with propensity scoring, the two cohorts were comprised of 990 patients each. Observed differences in 90-day complication rates were not statistically or clinically significant (ASC=9.1% vs. HOPD=10.3%; p=.362) nor were readmissions (ASC=4.5% vs. HOPD=5.3%; p=.466). On average, performing surgery in an ASC versus HOPD resulted in significant cost savings of over $2,000/case in Medicare Advantage ($5,814 vs. $7,829) and over $3,500/case ($10,116 vs. $13,623) in commercial beneficiaries. CONCLUSION: Performing single-level decompression surgeries in an ASC compared with HOPDs was associated with approximately $2,000 to $3,500 cost-savings per case with no statistically significant impact on complication or readmission rates.