Kicker Jennifer S, Timbie Cynthia Y, Kline Susan L
Department of Pediatrics, Pediatric Sedation Unit, Walter Reed National Military Medical Center, Bethesda, MD 20889, USA.
Department of Public Health, Industrial Hygiene Service, Walter Reed National Military Medical Center, Bethesda, MD 20889, USA.
Mil Med. 2025 Jun 30;190(7-8):e1765-e1771. doi: 10.1093/milmed/usae523.
Nitrous oxide (N2O) is commonly used in pediatric procedural sedation. It is an attractive option to facilitate intravenous line placement, as it does not extend sedation recovery from subsequently administered agents. Although debate exists regarding health consequences of occupational exposure now that scavenging of exhaled gases is common, cooperation of pediatric patients to maximize engineering controls is not guaranteed and can contribute to repeated exposure over the course of a clinician's career. There is no global consensus on personal exposure limits, but the National Institute for Occupational Safety and Health published U.S. guidelines. A dosimetry survey of our sedation team during a short N2O procedure for intravenous line placement exceeded the National Institute for Occupational Safety and Health Recommended Exposure Limit (REL) of 25 parts per million. We designed a process improvement initiative to reduce occupational exposure below the Recommended Exposure Limit on serial surveys.
A continuous flow, titratable, full-face mask N2O delivery system with scavenging by a central vacuum connection was used. A retrospective chart review of N2O procedures performed before the initial dosimetry survey revealed practice trends in provider behavior during N2O administration. Initiation of N2O gas flow and maintenance of face mask seal on an uncooperative patient were identified as two sources of variability. Two-handed face-masking technique, initiation of N2O gas flow only after masking, and continued masking for 2 min of exhaled scavenging were standardized and socialized as best practices. Subsequent dosimetry surveys of the sedation team were coordinated by Industrial Hygiene.
Pre- and post-intervention phases were 17 months each and included 92 and 201 N2O patients, respectively. Six dosimetry surveys occurred in the post phase. Intravenous line placement was the typical procedure surveyed. Dosimetry results for all team members during surveys 1-4 were below the REL, with 14 of 16 samples falling below the level of quantitation. Elevated dosimetry results in survey 5 prompted reevaluation of work practices and equipment. A loose component on the delivery system was discovered, corrected, and incorporated as a pre-procedure check. With no further changes to work practices, dosimetry results were below the REL for survey 6.
We layered work practice changes atop engineering controls to reduce occupational exposure levels for medical team members. We utilized dosimetry as a lagging indicator, prompting frequent reassessments of our equipment and processes that we might not otherwise have performed. Pediatric sedation programs are encouraged to consider whether Industrial Hygiene resources might provide synergy to process improvement efforts with inhalational sedation agents.
一氧化二氮（N₂O）常用于儿科程序性镇静。它是促进静脉置管的一个有吸引力的选择，因为它不会延长后续使用药物后的镇静恢复时间。尽管现在呼出气体清除已很普遍，但关于职业暴露对健康的影响仍存在争议，儿科患者不一定会配合以最大限度地发挥工程控制措施的作用，这可能导致临床医生在职业生涯中反复暴露。关于个人暴露限值尚无全球共识，但美国国家职业安全与健康研究所发布了美国指南。在一次用于静脉置管的短时间N₂O操作过程中，我们对镇静团队进行的剂量测定调查结果超过了美国国家职业安全与健康研究所建议的百万分之25的暴露限值。我们设计了一项过程改进计划，以在系列调查中将职业暴露降低到建议暴露限值以下。
使用了一种通过中央真空连接进行清除的连续流动、可滴定的全面罩N₂O输送系统。对首次剂量测定调查之前进行的N₂O操作进行回顾性图表审查，揭示了N₂O给药期间医护人员行为的实践趋势。在不合作的患者身上启动N₂O气流以及保持面罩密封被确定为两个可变因素。双手面罩技术、仅在戴上面罩后启动N₂O气流以及在呼出气体清除2分钟期间持续戴面罩被标准化并作为最佳实践进行推广。随后由工业卫生部门协调对镇静团队进行剂量测定调查。
干预前和干预后阶段各为17个月，分别包括92例和201例接受N₂O治疗的患者。干预后阶段进行了6次剂量测定调查。静脉置管是调查的典型操作。在第1 - 4次调查期间，所有团队成员的剂量测定结果均低于建议暴露限值，16个样本中有14个低于定量水平。第5次调查中剂量测定结果升高促使对工作实践和设备进行重新评估。发现输送系统上有一个松动部件，进行了纠正并将其纳入操作前检查。在工作实践没有进一步改变的情况下，第6次调查的剂量测定结果低于建议暴露限值。
我们在工程控制措施之上叠加工作实践的改变，以降低医疗团队成员的职业暴露水平。我们将剂量测定用作滞后指标，促使我们频繁重新评估设备和流程，否则我们可能不会这样做。鼓励儿科镇静项目考虑工业卫生资源是否可以为使用吸入性镇静剂的过程改进工作提供协同作用。
