Genicular nerve block for emergency department patient: a successful management of subacute osteoarthritic knee pain.

The genicular nerve block (GNB) performed under ultrasound is a common procedure in the perioperative and outpatient setting for the treatment of surgical knee pain and osteoarthritis. It provides motor-sparing analgesia to the knee, making it a potential alternative to other modes of pain management in the emergency department (ED). We present an elderly woman with acute-on-chronic osteoarthritic knee pain which was relieved for a week after a GNB during her ED visit. In patients with knee pain, the ultrasound guided GNB has the potential to provide short-term analgesia for patients with pain refractory to other modes of analgesia. The GNB shows promise as a reliable contribution to a multimodal approach to pain management in the ED setting.

Sulfhemoglobinemia and methemoglobinemia following acetaminophen overdose.

Introduction: Though acetaminophen overdoses are common, acetaminophen induced methemoglobinemia is rare and it is thought to be due to oxidative stress from reactive metabolites. However, few prior cases of sulfhemoglobinemia in the setting of acetaminophen overdose have been reported. We report a case of mixed methemoglobinemia and sulfhemoglobinemia in the setting of a large, isolated acetaminophen ingestion. Case report: A 30-year-old African American male presented after intentionally ingesting 50 tablets of 500 mg acetaminophen two days prior. He was cyanotic and tachypneic. Peripheral oxygen saturation was 78 % on room air and minimally improved with high-flow oxygen. He was noted to have leukocytosis, thrombocytopenia, anion gap metabolic acidosis with lactic acidemia, acute kidney injury, transaminitis, hyperbilirubinemia, and coagulopathy. Arterial partial pressure of oxygen was normal. Methemoglobin and sulfhemoglobin concentrations were 8.5 % and 5.2 %, respectively. Along with intravenous N-acetylcysteine, methylene blue was administered without clinical improvement. Hemolytic anemia was subsequently noted. Glucose-6- phosphate dehydrogenase (G6PD) deficiency was then confirmed with a quantitative assay and genetic testing. He also received one dose of intravenous metoclopramide. The patient ultimately required eight units of packed red blood cells and several weeks of hemodialysis before discharge on hospital day 43. Discussion: Acetaminophen is structurally related to compounds known to cause methemoglobinemia and sulfhemoglobinemia. We hypothesize that these dyshemoglobinemias were triggered by acetaminophen-induced oxidative stress. The role of G6PD deficiency in the formation of sulfhemoglobinemia is unclear. Acetaminophen overdoses presenting with methemoglobinemia should prompt concern for underlying G6PD deficiency. Coincidental sulfhemoglobinemia should be considered if the clinical presentation is more severe than the methemoglobin concentration alone would suggest. Use of methylene blue in this case, despite the low measured methemoglobin percentage, which likely triggered hemolytic anemia; methylene blue use in a similar circumstance should be weighed carefully against the risk of harm.

Ultrasound-Guided Caudal Epidural Steroid Injection for Back Pain: A Case Report of Successful Emergency Department Management of Radicular Low Back Pain Symptoms.

BACKGROUND: Radicular low back pain is difficult to treat and commonly encountered in the Emergency Department (ED). Pain associated with acute radiculopathy results in limited ability to work, function, and enjoy life, and is associated with increased risk of chronic opioid therapy. In this case report, we describe the first ED-delivered ultrasound-guided caudal epidural steroid injection (ESI) used to treat medication-refractory lumbar radiculopathy, which resulted in immediate and sustained resolution of pain. CASE REPORT: A 56-year old man with a past medical history of chronic lumbar radiculopathy presented to the ED with acute low back and right lower-extremity pain. Based on history and physical examination, a right L5 radiculopathy was suspected. His pain was poorly controlled despite multimodal analgesia, at which point he was offered admission or an ultrasound-guided caudal ESI. The procedure was performed using dexamethasone, preservative-free normal saline, and preservative-free 1% lidocaine solution, after which the patient reported 100% resolution of his pain and requested discharge from the ED. Why Should an Emergency Physician Be Aware of This? The safety and efficacy of ultrasound-guided caudal ESIs have been established, but there is a paucity of literature exploring their application in the ED. We present a case of a refractory lumbar radiculopathy successfully treated with an ultrasound-guided caudal ESI. ED-performed epidurals can be one additional tool in the emergency physician arsenal to treat acute or chronic lumbar radiculopathy.

Patients with sentinel lymph node positive melanoma: Who needs completion lymph node dissection?

INTRODUCTION: Completion lymph node dissection (CLND) for melanoma after positive sentinel lymph node biopsy (SLNB) was recently shown to improve regional but not overall survival, likely due to the majority of patients harboring no further nodal disease. We sought to determine predictors of non-sentinel node (NSN) positivity. METHODS: Retrospective review of prospectively collected data on melanoma patients undergoing SLNB. RESULTS: 116 patients underwent 119 CLNDs. The incidence of NSN positivity was 17.6%; the average number of positive NSNs in those cases was 1.5. Cervical and inguinofemoral location were most likely to yield positive NSN(s) (40% each). Conversely, the axilla was least likely at 18% (p < 0.001). The average number of nodes harvested was 13 for NSN negative cases and 20 for NSN positive cases (p = 0.005). Tumor thickness increased the probability of positive NSN(s) (OR 1.2, p = 0.02). CONCLUSIONS: Tumor thickness and nodal basin were predictors of NSN metastasis, factors that could help determine which patients may benefit from CLND. Further, CLNDs with fewer nodes may inadequately clear residual nodal disease.