RESUMEN
To describe the cardiovascular changes following intramuscular (handled) and intravascular (undisturbed, via intraarterial catheter) alfaxalone administration, we studied 20 healthy ball pythons (Python regius) in a randomised, prospective study. The pythons were instrumented with occlusive arterial catheters to facilitate undisturbed, continuous monitoring of heart rate and blood pressure. Six pythons were administered intramuscular (IM) saline, followed by 20 mg/kg IM alfaxalone, and were manually restrained for both injections. Six pythons received intraarterial (IA) saline, followed by 10 mg/kg IA alfaxalone, and remained undisturbed for both injections. Arterial blood samples were taken at 0, 12 and 60 min post-injection, and heart rate and blood pressure were recorded for 60 min. The remaining eight snakes received 20 mg/kg IM or 10 mg/kg IA alfaxalone (n = 4 per treatment) and were not handled for intubation 10 min post-injection, to examine the effects of handling during anaesthesia. IM administration of 20 mg/kg alfaxalone or an equivalent volume of saline elicited a profound tachycardia and hypertension, which recovered to resting values after 20 min. However, when 10 mg/kg alfaxalone or saline were injected IA, mild hypotension and a lower magnitude tachycardia occurred. Arterial PCO2 and PO2, pH and lactate concentrations did not change following IA alfaxalone, but an acidosis was observed during IM alfaxalone anaesthesia. There were no significant changes in plasma catecholamines and corticosterone among treatments. Handling for injection and during anaesthesia associated with intubation significantly affects cardiovascular parameters, whereas alfaxalone per se only elicits minor changes in cardiovascular physiology.
RESUMEN
Procedural extinction is sometimes associated with a temporary increase in responding known as an extinction burst. Extinction bursts present unique challenges in the context of treating behavior targeted for reduction. The present study updates the prevalence of extinction bursts using a clinical sample (N = 108) receiving treatment for targeted behavior. The prevalence of extinction bursts in our sample (24%) was consistent with that in prior literature. The extinction-burst magnitude decreased across sessions after extinction was contacted during treatment, but this sample did not demonstrate decreased persistence or magnitude of extinction bursts across successive transitions from baseline to treatment. We also examined the prevalence and magnitude of extinction bursts based on the function and topography of targeted behavior and treatment components and found no consistent relation among these variables. These findings should lead clinicians to prepare for transient extinction bursts when implementing extinction-based treatment for challenging behavior.
RESUMEN
Osteoderms (ODs) are mineralized tissue embedded within the skin and are particularly common in reptiles. They are generally thought to form a protective layer between the soft tissues of the animal and potential external threats, although other functions have been proposed. The aim of this study was to characterize OD variation across the lizard body. Adults of three lizard species were chosen for this study. After whole body CT scanning of each lizard, single ODs were extracted from 10 different anatomical regions, CT scanned, and characterized using sectioning and nanoindentation. Morphological analysis and material characterization revealed considerable diversity in OD structure across the species investigated. The scincid Tiliqua gigas was the only studied species in which ODs had a similar external morphology across the head and body. Greater osteoderm diversity was found in the gerrhosaurid Broadleysaurus major and the scincid Tribolonotus novaeguineae. Dense capping tissue, like that reported for Heloderma, was found in only one of the three species examined, B. major. Osteoderm structure can be surprisingly complex and variable, both among related taxa, and across the body of individual animals. This raises many questions about OD function but also about the genetic and developmental factors controlling OD shape.
RESUMEN
This study was designed to analyze the departmental changes in transitioning the Emergency Department (ED)-run Observation Medicine Unit's routine noninvasive cardiac evaluation from the traditional standard-of-care procedures to coronary computed tomography angiography (CCTA). While the routine use of CCTA for the evaluation of chest pain has been deemed feasible and safe, provider confidence appears apprehensive, and ordering patterns appear reluctant to change. We conducted a retrospective analysis of data from two risk-matched cohorts of ED patients who presented with symptoms suggestive of acute coronary syndrome (ACS) but without ischemic electrocardiogram (ECG) changes or positive troponin. Endpoints included length of stay, major adverse cardiovascular event (MACE) rates at 28 days, recidivism rate, and downstream findings on coronary catheterization. The adoption of CCTA led to a significant reduction in the length of stay for patients in the ED-run Observation Medicine Unit. Provider and nursing education initiatives were crucial in overcoming initial resistance and improving the implementation of CCTA. Post-education, there was a marked increase in the volume of CCTA performed and a decrease in the length of stay, enhancing overall departmental throughput. The results suggest that CCTA offers a reliable and efficient diagnostic alternative to traditional noninvasive tests, with high diagnostic accuracy contributing to faster decision-making and reduced need for invasive procedures. Continuous education for providers and nursing staff was essential to ensure adherence to the new protocol and improve clinical outcomes. Transitioning to CCTA for routine noninvasive cardiac evaluation in the ED-run Observation Medicine Unit demonstrated significant efficiency and diagnostic accuracy benefits. Successful implementation requires targeted educational efforts to ensure competency and confidence among healthcare providers. The findings support the integration of CCTA into standard clinical practice for the evaluation of chest pain in the emergency setting, with future research needed to validate these results in broader patient populations and assess long-term outcomes.