Measuring success: A comparison of ultrasound and landmark guidance for knee arthrocentesis in a cadaver model.

OBJECTIVE: Knee arthrocentesis can be performed by landmark (LM) or ultrasound (US) guidance. The goal of performing knee arthrocentesis is to obtain synovial fluid, however, it is also important to consider the number of attempts required and accidental bone contacts that occur. This study evaluates procedural success without bone contact in knee arthrocentesis and compares both LM and US guided techniques in a cadaver model. METHODS: This was a randomized crossover study comparing US vs LM guidance for arthrocentesis in a single academic center. Volunteers were randomized to perform both LM and US guided knee arthrocentesis on cadavers. The primary outcome was procedural success, defined as first attempt aspiration of synovial fluid without bone contact. Secondary outcomes included number of attempts, number of bone contacts, time to aspiration, and confidence. RESULTS: Sixty-one participants completed the study with a total of 122 procedures performed. Procedural success without bone contact was greater in the US group (84% vs 64% p = 0.02). Time to aspiration was longer for US (38.75 s vs 25.54 s p = 0.004). Participants were more confident with US compared to LM both before the procedure on a Visual Analog Scale from 1 to 100 (29 vs 21 p = 0.03) as well as after the procedure (83 vs 69 p = 0.0001). Participants had a greater median increase in confidence with US following training (44 vs 26 p = 0.01). CONCLUSIONS: Study participants had greater procedural success without bone contact when US guidance was used. The increase in confidence following training was greater for US guidance than the LM method. Use of US guidance may offer a benefit by allowing for better needle control and avoidance of sensitive structures for clinicians performing knee arthrocentesis.

Optic nerve sheath diameter in severe preeclampsia with neurologic features versus controls.

BACKGROUND: Optic nerve sheath diameters (ONSD) have been validated as an accurate screening tool to detect elevated intracranial pressure in hypertensive encephalopathy. The neurologic manifestations of preeclampsia and/or eclampsia mimic those of hypertensive encephalopathy. This study was performed to assess the incidence of elevated optic nerve sheath diameters of patients with severe preeclampsia and neurologic criteria compared to non-preeclamptic patients. The secondary objective was to determine baseline optic nerve sheath diameters in patients with severe preeclampsia without neurologic criteria and preeclampsia without severe features. METHODS: Single site cohort study including 62 pregnant women 18 years or older and 20 weeks or further gestation. Patients with preeclampsia without severe features, preeclampsia with severe features by non-neurologic criteria, preeclampsia with severe features with neurologic criteria, and patients without preeclampsia were enrolled via convenience sampling. One blinded reviewer measured sheath diameters; baseline demographics and pregnancy data were collected by chart review. Statistical analysis was completed with STATA/IC 16. Categorical variables were compared by the χ2 test. Continuous variables were presented as mean ± standard deviation, and discrete variables were presented as medians and compared by Kruskal-Wallis testing. Normality was confirmed by Shapiro-Wilk testing. Linear and logistic regression were used to test the association between the preeclampsia groups and optic nerve sheath diameters. Models were presented as unadjusted and adjusted for BMI, gestation, hypertension, diabetes, parity, and gravidity. RESULTS: The incidence of optic nerve sheath diameters > 5.8 mm was 43.8% in the severe preeclampsia with neurologic features cohort, and 42.1% in the control cohort, with a relative risk of 1.04. Patients with severe preeclampsia without neurologic features had sheath diameters of 5.75 mm ± 1.09 mm; non-severe preeclampsia patients had sheath diameters of 5.54 mm ± 1.26 mm. CONCLUSIONS: We did not find a significant elevated optic nerve sheath diameter relative risk between severe preeclampsia patients with neurologic features and non-preeclampsia control patients. This is the first study to assess a North American population utilizing ACOG criteria for severe and non-severe preeclampsia, with severe cohorts additionally stratified by neurologic criteria.

The Influence of Age on Propofol Dosing Requirements During Procedural Sedation in the Emergency Department.

Propofol is a frequently used agent for procedural sedation in the emergency department (ED). Some have suggested that propofol dosing in this setting should be adjusted in elderly patients; however, limited data exist supporting this recommendation. Additional factors that may contribute to altered propofol dose requirements in this setting have not been thoroughly explored. The objective of this analysis was to ascertain the effect age may have on the propofol dose required during procedural sedation in the ED. This retrospective study was conducted at a Level 1 academic medical center ED and included patients 18 years or older who received propofol for procedural sedation from 2015 to 2017. Those patients who were 18-64 years of age were compared with those 65 years or older. Between the two groups, total and weight-based propofol requirements for sedation, opioid doses, and adverse events were compared. This analysis included 101 procedural sedations. The median induction dose and opioid requirements before or during the procedure were not significantly different between the two groups. Compared with patients 18-64 years of age, those 65 years or older had significantly less total weight-based propofol requirements (p = 0.024) and required less total propofol for sedation (p = 0.007). In addition, patients 65 years or older required fewer repeat doses of propofol during the procedure than younger patients (p = 0.043). The incidence of adverse effects, including respiratory suppression, was not significantly different between the two groups. Patients 65 years or older may have lower weight-based propofol dosing requirements than younger patients. Utilizing a reduced total dose and repeat dosing strategy for propofol in this setting may be indicated. Further investigations are recommended to clarify factors that signal the need for more tailored dosing.

Point-of-Care Ultrasound Facilitates Management of Ruptured Ectopic Pregnancy.

ABSTRACT: Abdominal pain in the pregnant adolescent presents a diagnostic dilemma with potential life-threatening etiologies. We present a case where point-of-care ultrasound was used to facilitate diagnosis and expedite lifesaving management of a ruptured ectopic pregnancy. We further review the technique and literature for first-trimester transabdominal point-of-care ultrasound.

Ultrasound-Guided Posterior Tibial Nerve Block for Plantar Foot Foreign Body Removal.

Ultrasound-guided regional anesthesia is a growing modality within the pediatric emergency department. Here we present a case where a posterior tibial nerve block was used for anesthesia during foreign body removal from the plantar foot. We further review the technique and literature regarding this straightforward and highly effective procedure.