A hierarchy of effective teaching and learning to acquire competence in evidenced-based medicine

BACKGROUND: A variety of methods exists for teaching and learning evidence-based medicine (EBM). However, there is much debate about the effectiveness of various EBM teaching and learning activities, resulting in a lack of consensus as to what methods constitute the best educational practice. There is a need for a clear hierarchy of educational activities to effectively impart and acquire competence in EBM skills. This paper develops such a hierarchy based on current empirical and theoretical evidence. DISCUSSION: EBM requires that health care decisions be based on the best available valid and relevant evidence. To achieve this, teachers delivering EBM curricula need to inculcate amongst learners the skills to gain, assess, apply, integrate and communicate new knowledge in clinical decision-making. Empirical and theoretical evidence suggests that there is a hierarchy of teaching and learning activities in terms of their educational effectiveness: Level 1, interactive and clinically integrated activities; Level 2(a), interactive but classroom based activities; Level 2(b), didactic but clinically integrated activities; and Level 3, didactic, classroom or standalone teaching. SUMMARY: All health care professionals need to understand and implement the principles of EBM to improve care of their patients. Interactive and clinically integrated teaching and learning activities provide the basis for the best educational practice in this field

Rapid sevoflurane induction compared with thiopental

To examine whether the speed of induction of anesthesia with sevoflurane/nitrous oxide (N 2O) utilizing a 10-second vital capacity rapid inhalation induction (VCRII) followed by tidal breathing was similar or faster than cautious intravenous (IV) thiopental induction with inhaled N 2O. Prospective, randomized, double-blinded study. Veterans Affairs Medical Center. 50 male ASA physical status I, II, and III patients scheduled for general anesthesia. Patients were randomized to receive either 8% sevoflurane or IV thiopental. Patients were allocated to one of two groups of 25 patients each. In both groups, the breathing circuit was initially primed for 5 minutes with (4 L/min) and O 2 (2 L/min), while the Y-piece was occluded. In the sevoflurane group, the circuit was additionally primed with 8% sevoflurane. Patients were trained to perform a vital capacity breath. After maximal exhalation, the occluding plug was rapidly removed from the Y-piece and connected to the facemask. The patient then inspired to vital capacity, held his breath for 10 seconds, and then was allowed to breathe normally. At the end of the 10-second breathhold, and as the patient started normal breathing, either thiopental (thiopental group) or normal saline (sevoflurane group) was injected at a rate of 4 mL every 10 seconds. A study-blinded observer recorded the time to induction, as defined by the time to loss of eyelash reflex, and noted the occurrence of side effects. The speed of induction was the same for both groups ( p > 0.05). An average of eight breaths was required before loss of eyelash reflex. Side effects occurred in 36% of the patients in the thiopental group, and 32% in the sevoflurane group ( p > 0.05); these were minor and did not affect induction. Sevoflurane/N 2O VCRII as used in this investigation is an effective inhalation technique; it resulted in an induction time similar to that of slow IV thiopental with inhaled N 2O