A Case Report of Nitrous Oxide-induced Myelopathy: An Unusual Cause of Weakness in an Emergency Department.

INTRODUCTION: Weakness is a common symptom that within itself does not indicate a specific diagnosis. Recreational inhalant use such as nitrous oxide (NO) may not often be disclosed. Additionally, professional or occupational history, such as being a dentist or dental assistant, should be determined because of higher reported rates of NO misuse. Nitrous oxide can cause vitamin B12 deficiency and resulting neuropathy. Nitrous oxide toxicity can have a wide variation of presentations with or without laboratory abnormalities or remarkable imaging findings, which can further complicate a diagnosis of weakness secondary to NO use. CASE REPORT: A 33-year-old female presented to the emergency department with progressive bilateral leg numbness and objective weakness after repeated recreational NO use. After an extensive workup, she was found to have vitamin B12 deficiency and an electromyography study consistent with myeloneuropathy, despite normal imaging. She was prescribed high-dose vitamin B12 therapy and stopped using NO. One year after diagnosis, our patient maintained NO sobriety and had near-complete resolution of prior neurologic deficits. CONCLUSION: The use of recreational inhalant and the patient's occupation should be considered when a patient presents with weakness. Obtaining vitamin B12 and methylmalonic acid levels should be considered for diagnosis. However, NO-induced neuropathy can be seen in patients with normal vitamin B12 and methylmalonic levels and patients do not always have abnormal imaging findings. The healthcare team should consider the varied presentations and findings of substance-induced conditions such as NO toxicity.

Direct Endoscopic Necrosectomy With and Without Hydrogen Peroxide for Walled-off Pancreatic Necrosis: A Multicenter Comparative Study.

INTRODUCTION: Endoscopic necrosectomy has emerged as the preferred treatment modality for walled-off pancreatic necrosis. This study was designed to evaluate the safety and efficacy of direct endoscopic necrosectomy with and without hydrogen peroxide (H2O2) lavage. METHODS: Retrospective chart reviews were performed for all patients undergoing endoscopic transmural management of walled-off pancreatic necrosis at 9 major medical centers from November 2011 to August 2018. Clinical success was defined as the resolution of the collection by imaging within 6 months, without requiring non-endoscopic procedures or surgery. RESULTS: Of 293 patients, 204 met the inclusion criteria. Technical and clinical success rates were 100% (204/204) and 81% (166/189), respectively. For patients, 122 (59.8%) patients had at least one H2O2 necrosectomy (H2O2 group) and 82 (40.2%) patients had standard endoscopic necrosectomy. Clinical success was higher in the H2O2 group: 106/113 (93.8%) vs 60/76 (78.9%), P = 0.002. On a multivariate analysis, the use of H2O2 was associated with higher clinical success rate (odds ratio 3.30, P = 0.033) and earlier resolution (odds ratio 2.27, P < 0.001). During a mean follow-up of 274 days, 27 complications occurred. Comparing procedures performed with and without H2O2 (n = 250 vs 183), there was no difference in post-procedure bleeding (7 vs 9, P = 0.25), perforation (2 vs 3, P = 0.66), infection (1 vs 2, P = 0.58), or overall complication rate (n = 13 [5.2%] vs 14 [7.7%], P = 0.30). DISCUSSION: H2O2-assisted endoscopic necrosectomy had a higher clinical success rate and a shorter time to resolution with equivalent complication rates relative to standard necrosectomy.See the visual abstract at http://links.lww.com/AJG/B714.(Equation is included in full-text article.).

Trends in Diagnostic Point-of-Care Ultrasonography Reimbursement for Medicare Beneficiaries Among the US Emergency Medicine Workforce, 2012 to 2016.

STUDY OBJECTIVE: Point-of-care ultrasonography allows rapid diagnosis in the emergency department. A previous study found that a low prevalence of emergency medicine clinicians received point-of-care ultrasonography reimbursement in 2012 (0.7%). We determine nationwide point-of-care ultrasonography reimbursement patterns for 4 subsequent years. METHODS: We performed a cross-sectional study using 2012 to 2016 data from the Centers for Medicare & Medicaid Fee-for-Service Provider Utilization and Payment Data Part B, defining point-of-care ultrasonographic examinations using Current Procedural Terminology codes. The emergency medicine workforce was defined by emergency medicine, family medicine, internal medicine, critical care, and advanced practice providers who received emergency medicine-specific reimbursements. We compared patterns of point-of-care ultrasonography reimbursement among emergency physicians in 2012 versus 2016 through a 2-sample test of proportions. RESULTS: In 2012, 342 (0.7% of total) emergency medicine workforce clinicians were reimbursed for diagnostic point-of-care ultrasonography versus 801 (1.3%) in 2016. Emergency physicians represented an increasing proportion of the total workforce, increasing from 86.0% (95% confidence interval 82.3% to 89.6%) in 2012 (N=294) to 94.6% (95% confidence interval 93.1% to 96.2%) in 2016 (N=758). From 2012 to 2016, total point-of-care ultrasonography reimbursements increased from 13,697 to 31,717, with significant growth from echocardiograms (4,127 to 14,978), abdominal examinations (3,682 to 7,140), and thoracic examinations (801 to 5,278). CONCLUSION: The proportion of emergency medicine workforce clinicians receiving diagnostic point-of-care ultrasonography reimbursements, as well as the number of point-of-care ultrasonographic studies, more than doubled from 2012 to 2016. Efforts are needed to understand barriers to adoption of point-of-care ultrasonography because only a small proportion of the emergency medicine clinician workforce was reimbursed in any year.