Faculty Bibliography

PURPOSE/OBJECTIVE:The aim of this study was to determine rates of and possible reasons for guideline-discordant ordering of CT pulmonary angiography for the evaluation of suspected pulmonary embolism (PE) in the emergency department. METHODS:A retrospective review was performed of 212 consecutive encounters (January 6, 2016, to February 25, 2016) with 208 unique patients in the emergency department that resulted in CT pulmonary angiography orders. For each encounter, the revised Geneva score and two versions of the Wells criteria were calculated. Each encounter was then classified using a two-tiered risk stratification method (PE unlikely versus PE likely). Finally, the rate of and possible explanations for guideline-discordant ordering were assessed via in-depth chart review. RESULTS:The frequency of guideline-discordant studies ranged from 53 (25%) to 79 (37%), depending on the scoring system used; 46 (22%) of which were guideline discordant under all three scoring systems. Of these, 18 (39%) had at least one patient-specific factor associated with increased risk for PE but not included in the risk stratification scores (eg, travel, thrombophilia). CONCLUSIONS:Many of the guideline-discordant orders were placed for patients who presented with evidence-based risk factors for PE that are not included in the risk stratification scores. Therefore, guideline-discordant ordering may indicate that in the presence of these factors, the assessment of risk made by current scoring systems may not align with clinical suspicion.

Objective: Beta-adrenergic antagonists (BAAs) and calcium channel blockers (CCBs) negatively affect chronotropy and inotropy and are administered for many indications. The frequency of adverse reactions when BAAs and CCBs are administered concomitantly is infrequently described [1]. We reviewed the incidence of hemodynamic instability in patients in whom both a BAA and CCB were administered within a pharmacologically relevant time period.
Method(s): This was a quality improvement initiative in emergency department (ED) patients, performed at an urban, tertiary care hospital network from 1 October 2016 to 30 September 2018. Adult patients (>=18 years) who received both an intravenous BAA and CCB (in either order) within 6 hours were included. Primary outcomes were the incidence of bradycardia (heart rate <60 bpm) or hypotension (systolic blood pressure <90mmHg) after administration of the second medication. Secondary outcomes were associated diastolic blood pressure changes and administratively assigned primary and secondary diagnoses.
Result(s): Overall 56 ED patients met inclusion criteria. The median time between medication administration was 110 minutes for the cohort. The median decrease in pulse was 42 bpm. The median decrease in systolic blood pressure was 26mmHg, and the median diastolic blood pressure decrease was 11mmHg. According to the prespecified endpoints, 8.9% developed bradycardia, 8.9% developed systolic hypotension, and 17.9% developed either complication. These complications occurred at median times after second medication administration of 36 minutes for bradycardia and 10 minutes for hypotension. The most common diagnosis in patients who received concomitant BAA and CCB administration was atrial fibrillation (n= 39). All patients who developed bradycardia had atrial fibrillation (n= 4) or atrial flutter (n= 1). All patients who developed hypotension had atrial fibrillation (n= 5).
Conclusion(s): Despite a lack of published data, the administration of both BAAs and CCBs within 6 hours can cause significant hypotension and bradycardia in emergency department patients. Avoidance of concurrent administration of these medication classes or assurance of antidotal availability or pretreatment (i.e. with calcium salts) should be strongly encouraged