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Caffeine, one of the most commonly consumed psychoactive substances in the world, has long been known to alter neurological functions, such as alertness, attention, and memory. Despite caffeine's popularity, systematic investigations of its effects on synaptic plasticity in the brain are still lacking. Here we used a freely behaving rodent model of long‐term potentiation (LTP), a frequently studied form of synaptic plasticity, to assess the effects of caffeine consumption on hippocampal plasticity. LTP, which is a persistent increase in the strength of synaptic connections between neurons, is a cellular mechanism widely considered to underlie the processes of learning and memory. A group of 10‐week‐old Sprague–Dawley rats were administered caffeine (1 g/L) in their drinking water 3 weeks prior to collection of electrophysiological data. Another group of age‐matched animals received tap water and served as controls. Stimulating and recording electrodes were chronically implanted in the perforant pathway (PP) and dentate gyrus (DG) region of the hippocampus, respectively, to permit stable electrophysiological recordings of synaptic transmission at this synapse. Population spike amplitude (PSA) measures of LTP induction and duration were acquired in vivo while animals were freely behaving using a well‐established electrophysiological recording protocol. Results indicate caffeine‐treated rats (n = 9) had a significantly (P < 0.05) reduced level of LTP induction compared with controls (n = 10). More studies are needed to identify the exact mechanism through which caffeine alters LTP induction in this freely behaving model of synaptic plasticity.

BACKGROUND: Hip fractures typically occur in frail elderly patients. Preoperative specialty consults, in addition to hospitalist comanagement, are often requested for preoperative risk assessment. OBJECTIVE: Determine if preoperative specialty consults meaningfully influence management and outcomes in hip fracture patients, while being comanaged by hospitalists DESIGN: Retrospective cohort study SETTING: Tertiary care hospital in Connecticut PATIENTS: 491 patients aged 50 years and older who underwent surgery for an isolated fragility hip fracture, defined as one occurring from a fall of a height of standing or less. INTERVENTION: Presence or absence of a preoperative specialty consult MEASUREMENTS: Time to surgery (TTS), length of hospital stay (LOS), and postoperative complications RESULTS: 177 patients had a preoperative specialty consult. Patients with consults were older and had more comorbidities. Most consult recommendations were minor (72.8%); there was a major recommendation only for eight patients (4.5%). Multivariate analysis demonstrates that consults are more likely to be associated with a TTS beyond 24 hours (Odds Ratio [OR] 4.28 [2.79-6.56]) and 48 hours (OR 2.59 [1.52-4.43]), an extended LOS (OR 2.67 [1.78-4.03]), and a higher 30-day readmission rate (OR 2.11 [1.09-4.08]). A similar 30-day mortality rate was noted in both consult and no-consult groups. CONCLUSIONS: The majority of preoperative specialty consults did not meaningfully influence management and may have potentially increased morbidity by delaying surgery. Our data suggest that unless a hip fracture patient is unstable and likely to require active management by a consultant, such consults offer limited benefit when weighed against the negative impact of surgical delay.

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