Procedure lab used to improve confidence in the performance of rarely performed procedures.

OBJECTIVES: The objective of this study is to assess the efficacy of an animal procedure lab in improving the level of comfort in performing important emergency medicine procedures. The procedures included central venous line, chest tube, cricothyrotomy, pericardiocentesis, venous cutdown, and thoracotomy. METHODS: The students were physicians participating in the Tuscan Emergency Medicine Initiative as part of a certificate program in emergency medicine. They attended a 1-h lecture discussing the procedures to be performed. Participants filled out a questionnaire before and after the lab, which asked how many times they had performed each procedure, how comfortable they felt, on a five-point scale, performing each procedure, and whether they felt comfortable performing it by themselves, with assistance or whether they would not feel comfortable performing the procedure. Differences in rated numerical values for each procedure before and after the lab were analyzed using a two-tailed t-test. Alpha was set at 0.95. RESULTS: In all, there were 20 participants with a wide range of experience. A statistical improvement was observed in comfort level and willingness to perform the procedures independently (P<0.01). The only non-significant change was in willingness to perform central lines. CONCLUSIONS: The use of an animal lab improves the comfort level of practitioners in performing procedures. Although procedures are best learned on patients with supervision, this is not always feasible. This lab is a useful adjunct to teaching in emergency medicine and allows participants exposure to critical procedures.

Morphofunctional integration between skeletal myoblasts and adult cardiomyocytes in coculture is favored by direct cell-cell contacts and relaxin treatment.

The success of cellular cardiomyoplasty, a novel therapy for the repair of postischemic myocardium, depends on the anatomical integration of the engrafted cells with the resident cardiomyocytes. Our aim was to investigate the interaction between undifferentiated mouse skeletal myoblasts (C2C12 cells) and adult rat ventricular cardiomyocytes in an in vitro coculture model. Connexin43 (Cx43) expression, Lucifer yellow microinjection, Ca2+ transient propagation, and electrophysiological analysis demonstrated that myoblasts and cardiomyocytes were coupled by functional gap junctions. We also showed that cardiomyocytes upregulated gap junctional communication and expression of Cx43 in myoblasts. This effect required direct cell-to-cell contact between the two cell types and was potentiated by treatment with relaxin, a cardiotropic hormone with potential effects on cardiac development. Analysis of the gating properties of gap junctions by dual cell patch clamping showed that the copresence of cardiomyocytes in the cultures significantly increased the transjunctional current and conductance between myoblasts. Relaxin enhanced this effect in both the myoblast-myoblast and myoblast-cardiomyocyte cell pairs, likely acting not only on gap junction formation but also on the electrical properties of the preexisting channels. Our findings suggest that myoblasts and cardiomyocytes interact actively through gap junctions and that relaxin potentiates the intercellular coupling. A potential role for gap junctional communication in favoring the intercellular exchange of regulatory molecules, including Ca2+, in the modulation of myoblast differentiation is discussed.