Posterior Reversible Encephalopathy Syndrome (PRES).

Audience: Emergency medicine residents of all levels. Introduction: Posterior reversible encephalopathy syndrome (PRES) is a clinically significant cause of seizures, headache, neurologic deficit, and hypertensive emergency that is not uncommon in the emergency department. Posterior reversible encephalopathy syndrome was initially described as a clinical syndrome in 1996.1 It is an important cause of hypertensive emergency that is not often covered in depth in the emergency medicine curriculum since the true incidence and disease process continues to be researched.Populations who are at most risk for PRES include those with chronic hypertension, chronic renal disease, autoimmune disease, and immune suppression.2 Patients with PRES will often present with varied forms of encephalopathy and sometimes even focal neurologic symptoms that would suggest a cerebral vascular accident. These neurologic symptoms can include visual complaints and headache. Seizures are also frequently reported in association with PRES.3Early identification and appropriate management of PRES decreases morbidity and mortality without chronic neurologic sequelae. The pillars of diagnosis and management can be initiated in the emergency department. This includes a diagnosis made by a thorough history and physical exam and cerebral imaging.4 The mainstay of management is parenteral anti-hypertensives with proper blood pressure monitoring.5. Educational Objectives: By the end of the simulation, the learner will be able to: 1) manage an acute seizure 2) discuss imaging modalities to diagnose PRES 3) discuss medical management of PRES. Educational Methods: This simulation exercise is meant to be presented as a traditional medium-to-high-fidelity medical simulation case. With minor adjustments, it could be utilized as a low-fidelity case or an oral exam case. Research Methods: The educational content and general usefulness of this simulation was evaluated by open verbal (qualitative) feedback from a convenience sample of random participants following a completion of the case and debriefing by a participant group (n=30) of emergency medicine residents at a large 3-year residency training program. Results: The overall feedback was positive. Participants felt that it was a good opportunity to practice identifying PRES and managing it in a safe learning environment. They especially appreciated learning more about the pathophysiology of PRES, the high-risk factors for PRES, and management of the condition. Discussion: Posterior reversible encephalopathy syndrome, an uncommon condition, presents similar to many other benign and common complaints. It is crucial to be able to differentiate PRES from other causes of headache, visual disturbance, and seizures. It is important to keep PRES in mind when considering hypertensive emergencies. Many PGY-1 residents struggled to diagnose and treat PRES because it was often not on their differential, and this case helped broaden their differential. PGY-2 and PGY-3 were more frequently able to appropriately diagnose and treat PRES in this patient but found the case to be helpful in their decision-making and learning more about PRES pathophysiology. This case and associated high-yield debriefing session were effective for learners of all levels. Topics: Posterior reversible encephalopathy syndrome (PRES), altered mental status, seizure, headache, hypertensive emergency.

Prognostic value of point-of-care ultrasound during cardiac arrest: a systematic review.

BACKGROUND: Despite significant improvements in cardiopulmonary resuscitation, sudden cardiac arrest is one of the leading causes of mortality in the United States. Ultrasound is a widely available tool that can be used to evaluate the presence of cardiac wall motion during cardiac arrest. Several clinical studies have evaluated the use of ultrasound to visualize cardiac motion as a predictor of mortality in cardiac arrest patients. However, there are limited data summarizing the prognostic value of point of care ultrasound evaluation during resuscitation. We performed a systematic literature review of the existing evidence examining the clinical utility of point-of-care ultrasound evaluation of cardiac wall motion as a predictor of cardiac resuscitation outcomes. METHODS/RESULTS: We performed a systematic PubMed search of clinical studies up to July 23, 2019 evaluating point-of-care sonographic cardiac motion as a predictor of mortality following cardiac resuscitation. We included studies written in English that reviewed short-term outcomes and included adult populations. Fifteen clinical studies met inclusion criteria for assessing cardiac wall motion with point-of-care ultrasound and outcomes following cardiac resuscitation. Fourteen of the fifteen studies showed a statistically significant correlation between the presence of cardiac motion on ultrasound and short-term survival. This was most evident in patients with ventricular fibrillation or ventricular tachycardia as a presenting rhythm. Absence of cardiac motion non-survival. The data were pooled and the overall pooled odds ratio for return of spontaneous circulation in the presence of cardiac motion during CPR was 12.4 +/1 2.7 (p <  0.001). CONCLUSION: Evaluation of cardiac motion on transthoracic echocardiogram is a valuable tool in the prediction of short-term cardiac resuscitation outcomes. Given the safety and availability of ultrasound in the emergency department, it is reasonable to apply point-of-care ultrasound to cardiopulmonary resuscitation as long as its use does not interrupt resuscitation.

The efficacy of sonographic measurement of inferior vena cava diameter as an estimate of central venous pressure.

BACKGROUND: Central venous pressure (CVP) and right atrial pressure (RAP) are important parameters in the complete hemodynamic assessment of a patient. Sonographic measurement of the inferior vena cava (IVC) diameter is a non-invasive method of estimating these parameters, but there are limited data summarizing its diagnostic accuracy across multiple studies. We performed a comprehensive review of the existing literature to examine the diagnostic accuracy and clinical utility of sonographic measurement of IVC diameter as a method for assessing CVP and RAP. METHODS: We performed a systematic search using PubMed of clinical studies comparing sonographic evaluation of IVC diameter and collapsibility against gold standard measurements of CVP and RAP. We included clinical studies that were performed in adults, used current imaging techniques, and were published in English. RESULTS: Twenty one clinical studies were identified that compared sonographic assessment of IVC diameter with CVP and RAP and met all inclusion criteria. Despite substantial heterogeneity in measurement techniques and patient populations, most studies demonstrated moderate strength correlations between measurements of IVC diameter and collapsibility and CVP or RAP, but more favorable diagnostic accuracy using pre-specified cut points. Findings were inconsistent among mechanically ventilated patients, except in the absence of positive end-expiratory pressure. CONCLUSION: Sonographic measurement of IVC diameter and collapsibility is a valid method of estimating CVP and RAP. Given the ease, safety, and availability of this non-invasive technique, broader adoption and application of this method in clinical settings is warranted.