RESUMEN
BACKGROUND: Despite the well-known clinical effects of midazolam and ketamine, including sedation and memory impairment, the neural mechanisms of these distinct drugs in humans are incompletely understood. The authors hypothesized that both drugs would decrease recollection memory, task-related brain activity, and long-range connectivity between components of the brain systems for memory encoding, pain processing, and fear learning. METHODS: In this randomized within-subject crossover study of 26 healthy adults, the authors used behavioral measures and functional magnetic resonance imaging to study these two anesthetics, at sedative doses, in an experimental memory paradigm using periodic pain. The primary outcome, recollection memory performance, was quantified with d' (a difference of z scores between successful recognition versus false identifications). Secondary outcomes were familiarity memory performance, serial task response times, task-related brain responses, and underlying brain connectivity from 17 preselected anatomical seed regions. All measures were determined under saline and steady-state concentrations of the drugs. RESULTS: Recollection memory was reduced under midazolam (median [95% CI], d' = 0.73 [0.43 to 1.02]) compared with saline (d' = 1.78 [1.61 to 1.96]) and ketamine (d' = 1.55 [1.12 to 1.97]; P < 0.0001). Task-related brain activity was detected under saline in areas involved in memory, pain, and fear, particularly the hippocampus, insula, and amygdala. Compared with saline, midazolam increased functional connectivity to 20 brain areas and decreased to 8, from seed regions in the precuneus, posterior cingulate, and left insula. Compared with saline, ketamine decreased connectivity to 17 brain areas and increased to 2, from 8 seed regions including the hippocampus, parahippocampus, amygdala, and anterior and primary somatosensory cortex. CONCLUSIONS: Painful stimulation during light sedation with midazolam, but not ketamine, can be accompanied by increased coherence in brain connectivity, even though details are less likely to be recollected as explicit memories.
Asunto(s)
Encéfalo/efectos de los fármacos , Miedo/efectos de los fármacos , Ketamina/farmacología , Memoria/efectos de los fármacos , Midazolam/farmacología , Dolor/tratamiento farmacológico , Adolescente , Adulto , Analgésicos/farmacología , Anestésicos Intravenosos/farmacología , Encéfalo/diagnóstico por imagen , Estudios Cruzados , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Vías Nerviosas/efectos de los fármacos , Método Simple Ciego , Adulto JovenRESUMEN
STUDY OBJECTIVE: Despite the Accreditation Council for Graduate Medical Education scholarly activity requirement, incorporating education on scholarly fundamentals into residency is challenging. We designed and implemented an academic non-clinical rotation for Post Graduate Year-1 (PGY-1) interns and its association with subsequent resident scholarly productivity was determined. We hypothesized that early immersion in such a rotation would be associated with increased scholarly activity during residency. DESIGN: Retrospective educational comparative study, of two cohorts of anesthesiology residents in the graduating classes of 2015-2020. SETTING: Large anesthesiology residency program at a U.S. academic medical center. INTERVENTION: A one-month academic rotation titled Anesthesia Professional Practice for PGY-1 interns has been implemented since 2014. The rotation curriculum broadly covers important topics for scholarly projects and provides introductions to academic faculty and institutional resources. MEASUREMENTS: The scholarly products (abstracts, publications, book chapters, research protocols, and grant applications) were quantified using Scholarly Activity Points, a previously described metric that accounts for significance and the resident's contribution. Total Scholarly Activity Points for each resident and number of publications prior to residency were determined for both cohorts. Segmented regression was employed with Scholarly Activity Points as the outcome; participation in the early immersion rotation and prior publications were used as input variables. MAIN RESULTS: Resident participation in the early immersion rotation was significantly associated with higher Scholarly Activity Points. The confounding variable of pre-residency publication count was not significantly correlated to this increase. CONCLUSIONS: Immersion in a one-month academic program during PGY-1 internship may contribute to increased scholarly productivity during residency.
Asunto(s)
Anestesiología , Internado y Residencia , Anestesiología/educación , Curriculum , Educación de Postgrado en Medicina/métodos , Humanos , Inmersión , Práctica Profesional , Estudios RetrospectivosRESUMEN
How pain influences explicit memory is an active area of investigation, and next-day recognition was the primary outcome of this experiment. The data reported here were secondary measures of psychometrics to quantify interindividual variability between subjects and measure electrodermal activity (EDA) changes in response to experimental stimuli. Reliable EDA responses following painful electric shocks were obtained in the Learning portion of the experiment. During next-day testing, however, no reliable EDA responses were elicited, including to previously pain-paired experimental items.