Echocardiographic diagnosis and clinical implications of wide-open tricuspid regurgitation for evaluating right ventricular dysfunction in the emergency department.

The tricuspid regurgitation pressure gradient (TRPG) reflects the difference in pressure between the right ventricle and right atrium (ΔPRV-RA). Its estimation by echocardiography correlates well with that obtained using right-heart catheterization. An elevated TRPG is an important marker for identifying right ventricular dysfunction in both the acute and chronic settings. However, in the "wide-open" variant of TR, the TRPG counterintuitively falls. Failure to recognize this potential pitfall and underlying pathophysiology can cause underestimation of the severity of right ventricular dysfunction. This could lead to erroneous fluid tolerance assessments, and potentially harmful resuscitative and airway management strategies. In this manuscript, we illustrate the pathophysiology and potential pitfall of wide-open TR through a series of cases in which emergency physicians made the diagnosis using cardiac point-of-care ultrasound. To our knowledge, this clinical series is the first to demonstrate recognition of the paradoxically-low TRPG of wide-open TR, which guided appropriate management of critically ill patients in the emergency department.

The Poison Center as a pandemic response: establishment and characteristics of a COVID-19 hotline through the New Jersey Poison Center.

BACKGROUND: Poison Centers are uniquely positioned to respond to an unprecedented public health threat such as the COVID-19 pandemic, as fully operational 24-h hotlines already staffed with healthcare professionals. METHODS: On January 27, 2020 the New Jersey Poison Information and Education System (NJPIES) agreed to operate the New Jersey Coronavirus Hotline. Call patterns, subject matter, and staffing and infrastructure strategies that were implemented to meet the demand are described. In addition, a sample of 1500 individual calls were collected and analyzed in an endeavor to describe call times, call days, area from which the call originated, callers to the hotline, primary language of the caller, and why a call was placed to the hotline. Binomial regression analysis was utilized in an attempt to identify significant patterns. RESULTS: Since the inception of the hotline through October 31, NJPIES responded to 57,579 calls for COVID-19 information. Most calls (68.7%) were regarding testing for COVID-19 and for general questions/symptoms. Call types varied when they were analyzed by time of day with calls for general questions/symptoms and where to get tested for COVID-19 showing a significant association for the early morning hours, how to obtain test results being significantly associated with the afternoon hours, and how to renew or obtain a medical license showing a significant association to the evening hours. We additionally noted that specific call types became significant when analyzed on a week-to-week basis and as specific events, like the enactment of the CARES Act of 2020, occurred. CONCLUSION: Although not the traditional role of a regional Poison Control Center, pandemic response synergizes with the workflow of this hotline because the infrastructure, staffing, and healthcare expertise are already present. Poison centers can rapidly adapt through scaling and process change to meet the needs of the public during times of public health threats.

Mutational Analysis of Rab3 Function for Controlling Active Zone Protein Composition at the Drosophila Neuromuscular Junction.

At synapses, the release of neurotransmitter is regulated by molecular machinery that aggregates at specialized presynaptic release sites termed active zones. The complement of active zone proteins at each site is a determinant of release efficacy and can be remodeled to alter synapse function. The small GTPase Rab3 was previously identified as playing a novel role that controls the distribution of active zone proteins to individual release sites at the Drosophila neuromuscular junction. Rab3 has been extensively studied for its role in the synaptic vesicle cycle; however, the mechanism by which Rab3 controls active zone development remains unknown. To explore this mechanism, we conducted a mutational analysis to determine the molecular and structural requirements of Rab3 function at Drosophila synapses. We find that GTP-binding is required for Rab3 to traffick to synapses and distribute active zone components across release sites. Conversely, the hydrolytic activity of Rab3 is unnecessary for this function. Through a structure-function analysis we identify specific residues within the effector-binding switch regions that are required for Rab3 function and determine that membrane attachment is essential. Our findings suggest that Rab3 controls the distribution of active zone components via a vesicle docking mechanism that is consistent with standard Rab protein function.