Association Between Age-stratified Cohorts and Perioperative Complications and 30-day and 90-day Readmission in Patients Undergoing Single-level Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To assess perioperative complication rates and readmission rates after ACDF in a patient population of advanced age. SUMMARY OF BACKGROUND DATA: Readmission rates after ACDF are important markers of surgical quality and, with recent shifts in reimbursement schedules, they are rapidly gaining weight in the determination of surgeon and hospital reimbursement. METHODS: Patients 18 years of age and older who underwent elective single-level ACDF were identified in the National Readmissions Database (NRD) and stratified into 4 cohorts: 18-39 ("young"), 40-64 ("middle"), 65-74 ("senior"), and 75+ ("elderly") years of age. For each cohort, the perioperative complications, frequency of those complications, and number of patients with at least 1 readmission within 30 and 90 days of discharge were analyzed. χ 2 tests were used to calculate likelihood of complications and readmissions. RESULTS: There were 1174 "elderly" patients in 2016, 1072 in 2017, and 1010 in 2018 who underwent ACDF. Their rate of any complication was 8.95%, 11.00%, and 13.47%, respectively ( P <0.0001), with dysphagia and acute posthemorrhagic anemia being the most common across all 3 years. They experienced complications at a greater frequency than their younger counterparts (15.80%, P <0.0001; 16.98%, P <0.0001; 21.68%, P <0.0001). They also required 30-day and 90-day readmission more frequently ( P <0.0001). CONCLUSION: It has been well-established that advanced patient age brings greater risk of perioperative complications in ACDF surgery. What remains unsettled is the characterization of this age-complication relationship within specific age cohorts and how these complications inform patient hospital course. Our study provides an updated analysis of age-specific complications and readmission rates in ACDF patients. Orthopedic surgeons may account for the rise in complication and readmission rates in this population with the corresponding reduction in length and stay and consider this relationship before discharging elderly ACDF patients.

The Impact of Computer-Assisted Navigation on Charges and Readmission in Lumbar Spinal Fusion.

STUDY DESIGN: Retrospective National Database Study. OBJECTIVES: The purpose of this study is to evaluate the cost and patient outcomes associated with the utilization of computer-assisted navigation (CAN) utilization on patients undergoing lumbar spinal fusion. BACKGROUND: CAN systems have demonstrated comparable outcomes with instrumentation and procedural speed when compared with traditional techniques. In recent years, CAN systems have seen increased adoption in spinal surgery as they allow for better contextualization of anatomical structures with the goal of improving surgical accuracy and reproducibility. METHODS: The 2016 National Readmission Database was queried for patients with lumbar spinal fusion ICD-10 codes, with 2 subgroups created based on computer-aided navigation ICD-10 codes. Nonelective cases and patients below 18 years of age were excluded. Univariate analysis on demographics, surgical data, and total charges was performed. Postoperative complication rates were calculated based on diagnosis. Lastly, multivariate analysis was performed to assess navigation's impact on cost and postoperative outcomes. RESULTS: A total of 88,445 lumbar fusion surgery patients were identified. Of the total, 2478 (2.8%) patients underwent lumbar fusion with navigation utilization, while 85,967 (97.2%) patients underwent surgery without navigation. The average total charges were $150,947 ($150,058, $151,836) and $161,018 ($155,747, $166,289) for the non-CAN and CAN groups, respectively ( P <0.001). The 30-day readmission rates were 5.3% for the non-CAN cohort and 3.1% for the CAN cohort ( P <0.05). The 90-day readmission rates were 8.8% for the non-CAN cohort and 5.2% for the CAN cohort ( P <0.001). CONCLUSIONS: CAN use was found to be significantly associated with increased cost and decreased 30-day and 90-day readmissions. Although patients operated on with CAN had increased routine discharge and decreased readmission risk, future studies must continue to evaluate the cost-benefit of CAN. Limitations include ICD-10 codes for CAN utilization being specific to region of surgery, not to exact type. LEVEL OF EVIDENCE: Level III.

The Impact of Computer-Assisted Navigation on Charges and Readmission in Patients Undergoing Posterior Cervical Fusion Surgery.

STUDY DESIGN: Retrospective cohort study of 2016 Healthcare Cost and Utilization Project Nationwide Readmissions Database (NRD). OBJECTIVE: The aim was to evaluate cost and outcomes associated with navigation use on posterior cervical fusion (PCF) surgery patients. SUMMARY OF BACKGROUND DATA: Computer-assisted navigation systems demonstrate comparable outcomes with hardware placement and procedural speed compared with traditional techniques. Innovations in technology continue to improve surgeons' performance in complicated procedures, causing need to analyze the impact on patient care. METHODS: The 2016 NRD was queried for patients with PCF surgery ICD-10 codes. Cost and readmission rates were compared with and without navigation. Nonelective cases and patients below 18 years of age were excluded. Univariate analysis on demographics, surgical data, and total charges was performed. Lastly, multivariate analysis was performed to assess navigation's impact on cost and postoperative outcomes. RESULTS: A total of 11,834 patients were identified, with 137 (1.2%) patients undergoing surgery with navigation and 11,697 (98.8%) patients without. Average total charge was $131,939.47 and $141,270.1 for the non-navigation and navigation cohorts, respectively ( P =0.349). Thirty-day and 90-day readmission rates were not significantly lower in patients who received navigation versus those that did not ( P =0.087). This remained insignificant after adjusting for several variables, age above 65, sex, medicare status, mental health history, and comorbidities. The model adjusting for demographic and comorbidities maintained insignificant results of navigation being associated with decreased 30-day and 90-day readmissions ( P =0.079). CONCLUSIONS: Navigation use in PCF surgery was not associated with increased cost, and patients operated on with navigation did not significantly have increased routine discharge or decreased 90-day readmission. As a result, future studies must continue to evaluate the cost-benefit of navigation use for cervical fusion surgery. LEVEL OF EVIDENCE: Level III.

Wilderness Medicine Education in the Time of Social Distancing and COVID-19.

Wilderness medicine (WM) education has traditionally been conducted as in-person training. The current COVID-19 pandemic has forced medical schools to cancel clerkships and clinical electives and pivot to remote education. With online media modalities, it is possible to conduct a WM student elective remotely. The use of recorded audio lectures, instructional videos, choice-based simulations, and video conferencing allows students access to nearly all necessary content under the guidance of instructors. Although hands-on practicums are still essential to WM education, the process outlined here enables a temporary alternative during the time of necessary social distancing.

Safety and Efficacy of Locoregional Treatment during Immunotherapy with Nivolumab for Hepatocellular Carcinoma: A Retrospective Study of 41 Interventions in 29 Patients.

PURPOSE: To assess the safety of locoregional treatment (LRT) combined with nivolumab for intermediate and advanced hepatocellular carcinoma (HCC). MATERIALS AND METHODS: A single-center retrospective review included 29 patients undergoing 41 LRTs-transarterial chemoembolization or yttrium-90 transarterial radioembolization-60 days before or concurrently with nivolumab. Demographic, clinical, and laboratory values and adverse events were reviewed before and after nivolumab initiation and after each LRT. Treatment response and time to progression were assessed using Modified Response Evaluation Criteria in Solid Tumors. Clinical events, including nivolumab termination, death, and time of last follow-up, were assessed. RESULTS: Over a median nivolumab course of 8.1 months (range, 1.0-30) with a median of 14.2 2-week cycles (range, 1-53), predominantly Child-Pugh A (22/29) patients-12 Barcelona Clinic Liver Cancer (BCLC) B and 17 BCLC C-underwent 20 transarterial chemoembolization and 21 transarterial radioembolization LRTs at a median of 67 days (range, 48-609) after nivolumab initiation. Ten patients underwent multiple LRTs. During a median follow-up of 11.5 months (range, 1.8-35.1), no grade III/IV adverse events attributable to nivolumab were observed. There were five instances of grade III/IV hypoalbuminemia or hyperbilirubinemia within 3 months after LRT. There were no nivolumab-related deaths, and 30-day mortality after LRT was 0%. CONCLUSIONS: LRTs performed concurrently with nivolumab immunotherapy demonstrate an acceptable safety profile in patients with intermediate and advanced HCC.

Assess Before Rx: Reducing the Overtreatment of Asymptomatic Blood Pressure Elevation in the Inpatient Setting.

BACKGROUND: Asymptomatic blood pressure elevation is common in the inpatient setting. National guidelines recommend treating with oral agents to slowly decrease blood pressure; however, many clinicians use intravenous antihypertensive medications, which can lead to unpredictable changes in blood pressure. OBJECTIVE: To decrease the number of inappropriate orders (without symptoms of hypertensive emergency or order for NPO) of intravenous antihypertensives and adverse events associated with intravenous orders. DESIGN: Quasi-experimental study with multidisciplinary intervention. PARTICIPANTS: Inpatients with a one-time order for an intravenous antihypertensive agent from January 2016 to February 2018. MAIN MEASURES: The main outcomes were the total numbers of orders and inappropriate orders, adverse events, and alternate etiologies per 1,000 patient-days. As a balancing measure, patients were monitored for adverse events when blood pressure was elevated and not treated. KEY RESULTS: There were a total of 260 one-time orders of intravenous antihypertensives on two medical units. Inappropriate orders decreased from 8.3 to 3.3 per 1,000 patient days (P = .0099). Adverse events associated with intravenous antihypertensives decreased from 3.7 to 0.8 per 1,000 patient days (P = .0072). CONCLUSION: This initiative demonstrated a significant reduction in inappropriate use of IV antihypertensives and an associated reduction in adverse events.

Quantitative comparison of pre-therapy 99mTc-macroaggregated albumin SPECT/CT and post-therapy PET/MR studies of patients who have received intra-arterial radioembolization therapy with 90Y microspheres.

OBJECTIVE: The aim of our study was to compare yttrium -90 (90Y) dosimetry obtained from pre-therapy 99mTc-macroaggregated albumin (MAA) SPECT/CT versus post-therapy PET/MRI imaging among patients with primary or metastatic hepatic tumors. MATERIALS AND METHODS: Prior to 90Y radioembolization (RE), 32 patients underwent a scan using MAA mimicking 90Y distribution. After RE with 90Y microspheres, the patients were imaged on a PET/MRI system. Reconstructed images were transferred to a common platform and used to calculate 90Y dosimetry. The Passing-Bablok regression scatter diagram and the Bland and Altman method were used to analyze the difference between dosimetry values. RESULTS: For MAA and PET/MRI modalities, the mean liver doses for all 32 subjects were 43.0 ±â€¯20.9 Gy and 46.5 ±â€¯22.7 Gy, respectively, with a mean difference of 3.4 ±â€¯6.2 Gy. The repeatibility coefficient was 12.1 (27.0% of the mean). The Spearman rank correlation coefficient was high (ρ = 0.92). Although, there was a substantial difference in the maximum doses to the liver between the modalities, the mean liver doses were relatively close, with a difference of 24.0% or less. CONCLUSIONS: The two main contributors to the difference between dosimetry calculations using MAA versus 90Y PET/MRI can be attributed to the changes in catheter positioning as well as the liver ROIs used for the calculations. In spite of these differences, our results demonstrate that the dosimetry values obtained from pre-therapy MAA SPECT/CT scans and PET/MRI post-therapy 90Y studies were not significantly different.

Examining the Ability of Artificial Neural Networks Machine Learning Models to Accurately Predict Complications Following Posterior Lumbar Spine Fusion.

STUDY DESIGN: A cross-sectional database study. OBJECTIVE: The aim of this study was to train and validate machine learning models to identify risk factors for complications following posterior lumbar spine fusion. SUMMARY OF BACKGROUND DATA: Machine learning models such as artificial neural networks (ANNs) are valuable tools for analyzing and interpreting large and complex datasets. ANNs have yet to be used for risk factor analysis in orthopedic surgery. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried for patients who underwent posterior lumbar spine fusion. This query returned 22,629 patients, 70% of whom were used to train our models, and 30% were used to evaluate the models. The predictive variables used included sex, age, ethnicity, diabetes, smoking, steroid use, coagulopathy, functional status, American Society for Anesthesiology (ASA) class ≥3, body mass index (BMI), pulmonary comorbidities, and cardiac comorbidities. The models were used to predict cardiac complications, wound complications, venous thromboembolism (VTE), and mortality. Using ASA class as a benchmark for prediction, area under receiver operating curves (AUC) was used to determine the accuracy of our machine learning models. RESULTS: On the basis of AUC values, ANN and LR both outperformed ASA class for predicting all four types of complications. ANN was the most accurate for predicting cardiac complications, and LR was most accurate for predicting wound complications, VTE, and mortality, though ANN and LR had comparable AUC values for predicting all types of complications. ANN had greater sensitivity than LR for detecting wound complications and mortality. CONCLUSION: Machine learning in the form of logistic regression and ANNs were more accurate than benchmark ASA scores for identifying risk factors of developing complications following posterior lumbar spine fusion, suggesting they are potentially great tools for risk factor analysis in spine surgery. LEVEL OF EVIDENCE: 3.