RESUMEN
BACKGROUND: This study used existing literature and expert feedback to develop and pilot a novel error-avoidance checklist tool for cricothyrotomy in attending physicians. Prior literature has not focused on expert cricothyrotomy performance. While published checklists teach a specific procedural method, ideal for novice learners, this may hinder expert learners. OBJECTIVES: We endeavored to create a succinct error-avoidance checklist for cricothyrotomy. We hypothesized that such a checklist would prove feasible and acceptable to attending physicians. METHODS: This is a multicenter prospective checklist creation, evaluation, and feasibility study. Multiple experts pursued an iterative process to reach consensus on a 7-item error-avoidance checklist. The checklist was trialed for feasibility in pilot sessions at two sites by 45 attending emergency physicians who used the checklist for peer performance assessment and provided feedback. RESULTS: During the pilot implementation, 94% of respondents completed the procedure within the allotted 120 s. Greater than 85% of respondents agreed that four of the five procedural errors on the checklist were very or somewhat critical to avoid, including cutting >2 cm from midline, creating a false passage, failing to continuously maintain an object in the trachea, and injuring oneself during the procedure. Only 66% of participants felt severing the cricoid cartilage was critical. Successful breath administration and time under 120 s were critical for 100% and 95% of participants, respectively. The checklist was rated "easy" or "very easy" to use by 93% of participants, and 95% found this checklist reasonable for evaluating attending physicians. CONCLUSIONS: We present the multicenter development and implementation of a novel error-avoidance checklist tool for use in expert cricothyrotomy performance. Attending emergency medicine (EM) physicians rated our tool easy to use and agreed that most of the proposed errors were critical. Participants overwhelmingly agreed this tool would be reasonable for evaluation of cricothyrotomy performance among attending EM physicians.
RESUMEN
Cryogenic cooling of macromolecular crystals is commonly used for X-ray data collection both to reduce crystal damage from radiation and to gather functional information by cryogenically trapping intermediates. However, the cooling process can damage the crystals. Limiting cooling-induced crystal damage often requires cryoprotection strategies, which can involve substantial screening of solution conditions and cooling protocols. Here, recent developments directed towards rational methods for cryoprotection are described. Crystal damage is described in the context of the temperature response of the crystal as a thermodynamic system. As such, the internal and external parts of the crystal typically have different cryoprotection requirements. A key physical parameter, the thermal contraction, of 26 different cryoprotective solutions was measured between 294 and 72 K. The range of contractions was 2-13%, with the more polar cryosolutions contracting less. The potential uses of these results in the development of cryocooling conditions, as well as recent developments in determining minimum cryosolution soaking times, are discussed.