Which Model Is Better to Teach How to Perform Tube Thoracostomy: Synthetic, Cadaver, or Animal?

INTRODUCTION: The lack of standardized skill training reported by medical students in performing tube thoracostomies may be associated with higher complications. The ideal training model is yet to be determined. This study sought to evaluate three different models. METHODS: Between 2015 and 2017, 204 last-year medical students of Universidade de São Paulo with no prior training in tube thoracostomy were randomized into three groups: cadaver, pig, and synthetic models. All groups performed 1-d tube thoracostomy hands-on training and a 40-min theoretical class. The knowledge acquisition was measured by a comparison between a theoretical test before and 3 wk after the class, and the skills improvement was evaluated by a comparison between the skills test on the same day of the hands-on training and another after 24 wk (the retention skill test). A questionnaire was submitted to evaluate their satisfaction rate and self-reported confidence, as per a Likert scale. RESULTS: The theoretical post-test score was higher compared to the pretest score in all groups (P < 0.001). The retention skills test in the cadaver and synthetic groups decreased compared to the skills test (P = 0.01 and P = 0.007, respectively). There was no difference between the groups either in the theoretical test or in the skills test. Student satisfaction was higher in the cadaver and pig groups. The confidence perception increased in all groups after the training. CONCLUSIONS: The models used for tube thoracostomy training appear to have a similar impact on skills retention, knowledge acquisition, and confidence. Although the satisfaction rate is lower for the synthetic model, it has no biological risk or ethical issues and is more feasible.

Modulation of lipopolysaccharide-induced acute lung inflammation: Role of insulin.

The present study was undertaken to investigate the influence of insulin on lipopolysaccharide (LPS)-induced acute lung injury. Diabetic male Wistar rats (alloxan, 42 mg/kg, i.v., 30 days) and controls were instilled with saline containing LPS (750 microg/0.4 mL) or saline alone. The following analyses were performed 6 h there after: (a) total and differential cell counts in bronchoalveolar lavage (BAL) fluid, (b) quantification of tumor necrosis factor alpha, interleukin (IL) 1beta, IL-10, and cytokine-induced neutrophil chemoattractant 1 in the BAL (enzyme-linked immunosorbent assay), (c)immunohistochemistry for intercellular adhesion molecule 1 and E-selectin on lung vessels, and (d) quantification of metalloproteinases (MMP) 2 and 9 in the BAL (zymography). Relative to controls, diabetic rats exhibited a reduction in the number of neutrophils (80%) and reduced concentrations of tumor necrosis factor alpha (56%), IL-1beta (66%), and IL-10 (35%) after LPS instillation. Cytokine-induced neutrophil chemoattractant 1 levels did not differ between groups. Increased levels of MMP-2 (90%) and MMP-9 (500%) were observed in diabetic rats compared with controls. Treatment of diabetic rats with neutral protamine Hagedorn insulin (4 IU, s.c.), 2 h before LPS instillation, completely restored the number of neutrophils and concentrations of cytokines in the BAL fluid. Despite no significant differences between diabetic and control groups, there was a remarkable increase in intercellular adhesion molecule 1 and E-selectin expression on lung vessels after insulin treatment. Levels of MMP-2 and MMP-9 did not change after treatment with insulin. Levels of corticosterone were equivalent among groups. Data presented suggest that insulin modulates the production/release of cytokines and the expression of adhesion molecules controlling, therefore, neutrophil migration during the course of LPS-induced acute lung inflammation.