Liu, Liang Yen

OBJECTIVE Determine if a longitudinal point-of-care ultrasonography (POCUS) elective for medical students is effective in improving POCUS knowledge. METHODS We share the format of our longitudinal POCUS elective for medical students. To evaluate the efficacy of our longitudinal elective, we compare the difference between pre-elective and post-elective scores on a POCUS test using a paired t-test with threshold of statistical significance of p ≤ .05. We also share the results of a post-elective survey evaluating the effectiveness and quality of the longitudinal POCUS elective. RESULTS Pretest mean score was 56.3% (σ = 13.6), while posttest mean score was 73.3% (σ = 9.4), with an average score improvement of 17.0% (95% CI 9.9-24.0%, p < .0001). All students strongly or moderately agreed that they would recommend the elective to future medical students, that they were more confident with their POCUS skills after completing the elective, that the time commitment of the elective was appropriate, and that they felt they had the time to fit the elective into their schedule as a medical school student. Most students (56.7%) strongly or moderately agreed that the knowledge gained from the POCUS elective had helped them in their clinical rotations. CONCLUSIONS Our longitudinal POCUS curriculum subjectively and objectively improves medical students’ POCUS knowledge while remaining accessible to students. We share our unique longitudinal POCUS elective curriculum, the format of which and its benefits are transferable to other medical schools. Through this, we hope to provide others with ideas on how they may implement a longitudinal POCUS elective.

SummaryBackgroundPredictive models for eosinophilic oesophagitis (EoE) may not fully rule in the diagnosis.AimTo develop a reverse model that predicts against EoE to eliminate the need for oesophageal biopsies.MethodsIn this two‐centre study, a predictive model was developed (Mayo Clinic) and validated (University of North Carolina [UNC]). Cross‐sectional data from consecutive adult patients without prior EoE who underwent upper enoscopy with oesophageal biopsies were used. EoE cases had ≥15 eosinophils/high‐power field while controls had no eosinophils. Data were collected on patient clinical and endoscopic features. Multiple variable logistic regression was used to identify predictors of non‐EoE status while maintaining specificity ≥95%. A secondary model was developed to predict against the need for endoscopy in patients suspected of having EoE without alarm symptoms.ResultsThe Mayo and UNC cohorts consisted of 345 (EoE = 94, non‐EoE = 251) and 297 patients (EoE = 84, non‐EoE = 213), respectively. A primary model based on clinical and endoscopic features predicted against EoE with c‐statistic 0.92 (95% CI: 0.88–0.96), specificity 95%, and sensitivity 65%. This model was validated (UNC) with c‐statistic 0.87 (95% CI: 0.82–0.92). A simplified scoring system was created and a threshold of ≥12 points excluded EoE with 95% specificity and 50% sensitivity. A secondary model based on clinical characteristics alone predicted against EoE with c‐statistic 0.86 (95% CI: 0.82–0.90), specificity 95% and sensitivity 39% and validated (UNC) with c‐statistic 0.78 (95% CI: 0.71–0.85).ConclusionA simplified scoring system accurately identified a group of patients with a low likelihood of EoE where unnecessary oesophageal biopsies can be avoided, potentially resulting in resource and cost savings.

Précis: Surgical and clinical success rates were similar among Ahmed FP7, and Baerveldt 250 and 350 glaucoma drainage devices at three years. Purpose: To compare rates of surgical and clinical success in patients with Ahmed FP7 (FP7), Baerveldt 250 (B250), or Baerveldt 350 (B350) glaucoma drainage devices (GDDs). Design: A retrospective cohort study. Methods: A total of 157 eyes of 129 adult patients with FP7, B250, B350 GDDs, and 190 eyes of 99 medically controlled glaucoma patients were enrolled at a tertiary care institution from August 2017 through July 2019. They were followed through April 2020. The main outcome measures included surgical and clinical failure. Surgical failure was defined as intraocular pressure (IOP) outside 5–21 mm Hg, IOP reduced <20% below baseline, additional glaucoma surgery, GDD removal, or no light perception. Eyes that did not meet their goal IOP ranges or required secondary glaucoma interventions were deemed clinical failures. Results: A total of 43 (12.4%) FP7, 36 (10.4%) B250, 78 (22.5%) B350, and 190 (54.8%) medically treated control eyes were enrolled. By the postoperative year 3 visit, 10 (23.2%) FP7, 11 (30.6%) B250, and 32 (41.0%) B350 eyes had met a surgical failure criterion (P=0.127). There were no significant differences in the numbers of eyes meeting their IOP target ranges (P=0.510), and rates of secondary glaucoma surgeries (P=0.270). Overall clinical success was attained among 83.3% FP7, 81.8% B250, and 68.0% B350 eyes (P=0.447). Conclusions: The GDD groups were similar in their rates of success, based on both the surgical and clinical success definitions.

Abstract Background A patent foramen ovale (PFO) is a persistent embryonic defect in the interatrial septum. Platypnoea-orthodeoxia syndrome is characterized by positional hypoxaemia that is most commonly due to right-to-left shunting through a PFO. Dynamic right-to-left shunting through a PFO can also exacerbate positional hypoxaemia without platypnea-orthodeoxia syndrome. Case summary A 78-year-old woman with hyperthyroidism and paroxysmal atrial fibrillation (AF) presented with positional hypoxaemia exacerbated by supine positioning. Diagnostic testing revealed intermittent right-to-left shunting through a PFO triggered by worsening atrial functional tricuspid regurgitation and elevated right atrial pressures. Diuresis, rate control, and thyroidectomy initially led to resolution of positional hypoxaemia, but recurrent AF episodes triggered right-to-left shunting with recurrent desaturation. Left atrial and cavo-tricuspid isthmus ablation led to restoration of normal sinus rhythm and resolution of positional hypoxaemia without PFO closure. Discussion The clinical presentation of intermittent intracardiac right-to-left shunting can mimic decompensated heart failure with pulmonary oedema. Persistent hypoxaemia out of proportion to the degree of pulmonary oedema and minimally responsive to supplemental O2 should raise suspicion for right-to-left shunt aetiology. Positional arterial blood gases can facilitate the diagnostic evaluation of refractory hypoxaemia in cases of suspected shunting. Diagnostic imaging for PFO detection includes both transthoracic and transesophageal echocardiography with Valsalva manoeuver and agitated saline injection. Closure of a PFO for management of arterial deoxygenation syndromes should not be performed before treating other causes of arterial deoxygenation and optimizing factors that may exacerbate shunting across the PFO.