SAEM—State of the Society, 2001 *

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72900/1/j.1553-2712.2001.tb01152.x.pd

You Can Run, but You Can't Hide: The Academic Physician and Molecular Biology

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74773/1/j.1553-2712.1998.tb02766.x.pd

Developing Emergency Medicine Leaders: The AACEM/SAEM Chair Development Program at 5 Years

The Association of Academic Chairs of Emergency Medicine Chair Development Program (CDP) was started in 2014 to provide emergency medicine (EM) chairs and leaders who aspired to become academic chairs with EM‐specific leadership training. Each class participated in a 1‐year program, with five sessions taught primarily by EM leaders. Data from the first 5 years of the CDP are provided. A total of 81 participants completed the program (16% women). Twenty participants who were not chairs at entry have become EM chairs. Ratings of the CDP based on a survey of participants with a 94% response rate were very favorable. The CDP has been a popular and successful vehicle to increase leadership skills and prepare EM leaders for academic chair positions.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154449/1/acem13896_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154449/2/acem13896.pd

Effects of Cocaine in an Experimental Model of Traumatic Brain Injury

: Background: Cocaine intoxication is found in a significant subset of emergency department (ED) patients presenting with traumatic brain injury (TBI). Objectives: To investigate the effects of acute cocaine intoxication on physiologic and metabolic parameters in a model of experimental TBI. Methods: Under inhalational anesthesia, swine were instrumented and subjected to fluid percussion TBI of 3 atm. Two groups were studied: TBI and cocaine ( n = 7) and TBI only ( n = 7). Two sequential doses of cocaine hydrochloride were administered intravenously to the animals receiving cocaine: 4 mg/kg 10 minutes prior to injury and 2 mg/kg 1 minute prior to injury. Control animals received normal saline. Cardiorespiratory and cerebral physiologic data were monitored for 180 minutes following injury. Cerebral blood flow (CBF) was measured using dye-labeled microspheres. Serum cocaine levels were measured by gas chromatography/mass spectrometry. Results: Mean (±SD) cocaine levels at the time of injury were 1,771 (±403) ng/mL. All animals survived the 180-minute observation period. There was a trend toward higher intracranial pressure (ICP) in the control (15.4 ± 8.2) vs. cocaine-treated (11.1 ± 5.8) animals, although this did not reach statistical significance (p = 0.18). Cerebral venous lactate (CVL) levels also trended higher in the control (1.14 ± 0.22) vs. cocaine-treated (0.91 ± 0.19) groups (p = 0.06). Cerebral perfusion pressures (CPPs), however, did not differ between groups. The CBF values decreased significantly from baseline in both groups but were not different between groups. Conclusions: Cocaine-intoxicated animals subjected to TBI showed no significant difference in primary outcome measures of CPP or CBF, although a nonsignificant trend toward lower ICP was noted. Overall, acute cocaine intoxication did not adversely affect the physiologic parameters examined in this TBI model.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75460/1/j.aem.2004.11.028.pd

Too Big Too Fast? Potential Implications of the Rapid Increase in Emergency Medicine Residency Positions

Emergency medicine (EM) has expanded rapidly since its inception in 1979. Workforce projections from current data demonstrate a rapid rise in the number of accredited EM residency programs and trainee positions. Based on these trends, the specialty may soon reach a point of saturation, particularly in urban areas. This could negatively impact future trainees entering the job market as well as the career plans of medical students. More time and resources should be devoted to obtaining accurate projections, assessing the distribution of emergency physicians in rural versus urban settings, and implementing central workforce planning to protect the future of graduating trainees.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154425/1/aet210400.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154425/2/aet210400_am.pd

Effects of Ethanol in an Experimental Model of Combined Traumatic Brain Injury and Hemorrhagic Shock

Objectives: Given that clinical and laboratory studies suggest that ethanol and hemorrhagic shock (HS) potentiate traumatic brain injury (TBI), the authors studied the effects of ethanol in a model of combined TBI and HS. Methods: A controlled porcine model of combined TBI and HS was evaluated for the effect of ethanol on survival time, hemodynamic function, and cerebral tissue perfusion. Anesthetized swine (17–24 kg) were instrumented, splenectomized, and subjected to fluid percussion TBI with concurrent 25-mL/kg graded hemorrhage over 30 minutes. Two groups were studied: control ( n = 11) and ethanol ( n = 11). Ethanol, 3.5 g/kg intragastric, was given 100 minutes prior to TBI/HS. Systemic and cerebral physiologic and metabolic parameters were monitored for 2 hours without resuscitation. Regional cerebral blood flow (rCBF) and renal blood flow were measured with dye-labeled microspheres. Data were analyzed with 2-sample t-test and repeated-measures ANOVA. Results: Ethanol levels at the time of injury were 162 ± 68 mg/dL. Average TBI was 2.65 ± 0.35 atm. Survival time was significantly shorter in the ethanol group (60 ± 27 min vs 94 ± 28 min, p = 0.011). The ethanol group had significantly lower mean arterial pressure, cerebral perfusion pressure, and cerebral venous O 2 saturation in the postinjury period. Cerebral O 2 extraction ratios and cerebral venous lactate levels were significantly higher in the ethanol group. A trend toward lower postinjury rCBF in all brain regions was observed in the ethanol group. Conclusion: In this TBI/HS model, ethanol administration decreased survival time, impaired the hemodynamic response, and worsened measures of cerebral tissue perfusion.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72205/1/j.1553-2712.1998.tb02568.x.pd

Guidelines for the Management of Severe Head Injury: Are Emergency Physicians Following Them?

The Brain Trauma Foundation published “Guidelines for the Management of Severe Head Injury” in 1995. These evidence-based clinical guidelines (CGs) recommended against prophylactic hyperventilation and glucocorticoid use and advocated for aggressive blood pressure (BP) resuscitation, and the careful use of mannitol. Objective: To survey Michigan emergency physicians (MEPs) to test their adherence to these guidelines. Methods: An anonymous mail survey was sent to all 566 MEPs who are members of the American College of Emergency Physicians. Three clinical scenarios involving severe head injury were presented, all with Glasgow Coma Scale (GCS) scores of 8 or less. The physicians were asked to choose from 15 diagnostic and treatment options, which included: intubation and hyperventilation, BP resuscitation, intravenous (IV) mannitol administration, and IV glucocorticoid administration. Results: Three hundred nineteen (56%) surveys were returned. Forty-six percent [95% confidence interval (95% CI) = 40% to 51%] of the MEPs elected to use prophylactic hyperventilation; very few administered IV glucocorticoids. Seventy-eight percent (95% CI = 75% to 81%) corrected hypotension with systolic BP < 90 mm Hg; 83% (95% CI = 80% to 86%) also administered mannitol appropriately. Conclusions: A majority of MEPs are managing severe head injury patients in accordance with the “Guidelines for the Management of Severe Head Injury,” with the exception of avoiding prophylactic hyperventilation. More education and/or exposure to the evidence regarding prophylactic hyperventilation of severely head injured patients may improve adherence to the guidelines.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74731/1/aemj.9.8.806.pd

The role of historical and contemporary processes on phylogeographic structure and genetic diversity in the Northern Cardinal, Cardinalis cardinalis

Background Earth history events such as climate change are believed to have played a major role in shaping patterns of genetic structure and diversity in species. However, there is a lag between the time of historical events and the collection of present-day samples that are used to infer contemporary population structure. During this lag phase contemporary processes such as dispersal or non-random mating can erase or reinforce population differences generated by historical events. In this study we evaluate the role of both historical and contemporary processes on the phylogeography of a widespread North American songbird, the Northern Cardinal, Cardinalis cardinalis. Results Phylogenetic analysis revealed deep mtDNA structure with six lineages across the species\u27 range. Ecological niche models supported the same geographic breaks revealed by the mtDNA. A paleoecological niche model for the Last Glacial Maximum indicated that cardinals underwent a dramatic range reduction in eastern North America, whereas their ranges were more stable in México. In eastern North America cardinals expanded out of glacial refugia, but we found no signature of decreased genetic diversity in areas colonized after the Last Glacial Maximum. Present-day demographic data suggested that population growth across the expansion cline is positively correlated with latitude. We propose that there was no loss of genetic diversity in areas colonized after the Last Glacial Maximum because recent high-levels of gene flow across the region have homogenized genetic diversity in eastern North America. Conclusion We show that both deep historical events as well as demographic processes that occurred following these events are critical in shaping genetic pattern and diversity in C. cardinalis. The general implication of our results is that patterns of genetic diversity are best understood when information on species history, ecology, and demography are considered simultaneously

The role of historical and contemporary processes on phylogeographic structure and genetic diversity in the Northern Cardinal, Cardinalis cardinalis

<p>Abstract</p> <p>Background</p> <p>Earth history events such as climate change are believed to have played a major role in shaping patterns of genetic structure and diversity in species. However, there is a lag between the time of historical events and the collection of present-day samples that are used to infer contemporary population structure. During this lag phase contemporary processes such as dispersal or non-random mating can erase or reinforce population differences generated by historical events. In this study we evaluate the role of both historical and contemporary processes on the phylogeography of a widespread North American songbird, the Northern Cardinal, <it>Cardinalis cardinalis</it>.</p> <p>Results</p> <p>Phylogenetic analysis revealed deep mtDNA structure with six lineages across the species' range. Ecological niche models supported the same geographic breaks revealed by the mtDNA. A paleoecological niche model for the Last Glacial Maximum indicated that cardinals underwent a dramatic range reduction in eastern North America, whereas their ranges were more stable in México. In eastern North America cardinals expanded out of glacial refugia, but we found no signature of decreased genetic diversity in areas colonized after the Last Glacial Maximum. Present-day demographic data suggested that population growth across the expansion cline is positively correlated with latitude. We propose that there was no loss of genetic diversity in areas colonized after the Last Glacial Maximum because recent high-levels of gene flow across the region have homogenized genetic diversity in eastern North America.</p> <p>Conclusion</p> <p>We show that both deep historical events as well as demographic processes that occurred following these events are critical in shaping genetic pattern and diversity in <it>C. cardinalis</it>. The general implication of our results is that patterns of genetic diversity are best understood when information on species history, ecology, and demography are considered simultaneously.</p

Genetic Applications in Avian Conservation

A fundamental need in conserving species and their habitats is defining distinct entities that range from individuals to species to ecosystems and beyond (Table 1; Ryder 1986, Moritz 1994, Mayden and Wood 1995, Haig and Avise 1996, Hazevoet 1996, Palumbi and Cipriano 1998, Hebert et al. 2004, Mace 2004, Wheeler et al. 2004, Armstrong and Ball 2005, Baker 2008, Ellis et al. 2010, Winker and Haig 2010). Rapid progression in this interdisciplinary field continues at an exponential rate; thus, periodic updates on theory, techniques, and applications are important for informing practitioners and consumers of genetic information. Here, we outline conservation topics for which genetic information can be helpful, provide examples of where genetic techniques have been used best in avian conservation, and point to current technical bottlenecks that prevent better use of genomics to resolve conservation issues related to birds. We hope this review will provide geneticists and avian ecologists with a mutually beneficial dialogue on how this integrated field can solve current and future problems