Norris Robert L, Ngo Jessica, Nolan Karen, Hooker Giles
Department of Surgery, Stanford University, Stanford, CA, USA.
Wilderness Environ Med. 2005 Spring;16(1):16-21. doi: 10.1580/PR12-04.1.
To determine whether volunteers (with or without prior medical training) can correctly apply pressure immobilization (PI) in a simulated snakebite scenario after receiving standard instructions describing the technique.
Twenty emergency medicine physicians (residents and attendings) and 20 lay volunteers without prior formal medical training were given standard printed instructions describing the application of PI for field management of snakebite. They were then supplied with appropriate materials and asked to apply the technique five separate times (twice to another individual [one upper and one lower extremity] and three times to themselves [nondominant upper extremity, dominant upper extremity, and one lower extremity]). Successful application was defined a priori by four criteria previously published in the literature: wrap begins at the bite site, entire extremity is wrapped, splint or sling is applied, and pressures under the dressing are between 40 and 70 mm Hg in upper-extremity application and between 55 and 70 mm Hg in lower-extremity use. Pressures were determined using a specially designed skin interface pressure-measuring device placed at the simulated bite site.
The technique was correctly applied as judged by the preset criteria in only 13 out of 100 applications by emergency medicine physicians and in only 5 out of 100 applications by lay people. There was no significant difference in success rates between physicians and lay volunteers. Likewise, there was no significant difference in success based on which extremity was being wrapped. More detailed analysis revealed that the major contributor to failure was inability to achieve recommended target pressures.
Volunteers in a simulated snakebite scenario have difficulty applying PI correctly, as defined in the literature. The major source of failure is an inability to achieve recommended pressure levels under the dressing. New methods of instructing people in the proper use of PI or new technologies to guide or automate application are needed if this technique is to be used consistently in an effective manner for field management of bites by venomous snakes not known to cause significant local wound necrosis.
确定志愿者（有无医学培训经历）在接受描述压力固定法（PI）技术的标准指导后，能否在模拟蛇咬伤场景中正确应用该技术。
20名急诊医学医生（住院医师和主治医师）以及20名未接受过正规医学培训的外行人志愿者，收到了关于在蛇咬伤现场管理中应用PI的标准印刷说明。随后为他们提供了合适的材料，并要求他们将该技术分别应用五次（两次应用于另一个人[一次上肢和一次下肢]，三次应用于自身[非优势上肢、优势上肢和一次下肢]）。成功应用的定义事先依据先前文献中公布的四项标准确定：包扎从咬伤部位开始，整个肢体被包扎，应用夹板或吊带，上肢应用时敷料下的压力在40至70毫米汞柱之间，下肢应用时在55至70毫米汞柱之间。压力通过放置在模拟咬伤部位的专门设计的皮肤界面压力测量装置来确定。
根据预先设定的标准判断，急诊医学医生在100次应用中仅有13次正确应用了该技术，外行人志愿者在100次应用中仅有5次正确应用。医生和外行人志愿者的成功率没有显著差异。同样，根据包扎的肢体不同，成功率也没有显著差异。更详细的分析表明，失败的主要原因是无法达到推荐的目标压力。
在模拟蛇咬伤场景中，志愿者难以按照文献中定义的方式正确应用PI。失败的主要原因是无法在敷料下达到推荐的压力水平。如果要将该技术持续有效地用于对已知不会导致严重局部伤口坏死的毒蛇咬伤进行现场管理，就需要新的方法来指导人们正确使用PI，或者需要新技术来指导或自动应用该技术。
