Sessler D I, Badgwell J M
Department of Anesthesia, University of California-San Francisco, 94143-0648, USA.
Anesth Analg. 1998 Nov;87(5):1083-8. doi: 10.1097/00000539-199811000-00019.
The National Institute of Occupational Safety and Health (NIOSH) has established recommended exposure limits of 25 parts per million (ppm) as a time-weighted average for nitrous oxide and a ceiling of 2 ppm for volatile anesthetics. We quantified exposure of postanesthetic nurses to exhaled anesthetic gases. This study was conducted in the postanesthesia care unit (PACU) of a medium-sized hospital. PACU air exchanges averaged 8 vol/h; however, much of this air was recirculated. We evaluated 50 adults anesthetized with either isoflurane (n = 19) or desflurane (n = 31). Roughly half the patients were tracheally extubated in the operating room, whereas the others were extubated just after admission to the PACU. Exhaled anesthetic gases were sampled through a 20-m hose attached to the participating nurses' shoulders (breathing zone). We also evaluated nursing exposure to exhaled anesthetic gases during recovery of 15 patients who had been anesthetized with nitrous oxide. Exposure was quantified with lapel dosimeters. Anesthetic and recovery durations were each approximately 1 h, with most patients being tracheally extubated in the PACU. Breathing-zone anesthetic concentrations in the patients given isoflurane exceeded NIOSH recommendations in 37% of the patients, representing 12% of recovery time. Breathing-zone anesthetic concentrations in the patients given desflurane, however, exceeded NIOSH limits in 87% of the patients, representing 49% of recovery time. Altogether, noncompliant episodes were detected in 68% of these patients, representing 35% of the entire recovery duration. Breathing-zone anesthetic concentrations in the patients given nitrous oxide exceeded NIOSH limits in 53% of the patients. Our data suggest that postoperative nurses' exposure to exhaled anesthetic gases exceeds NIOSH limits under some circumstances.
Some epidemiological evidence suggests that exposure to waste anesthetic gases may be associated with reproductive toxicity. Accordingly, the National Institute of Occupational Safety and Health has established recommended exposure limits for nitrous oxide and volatile anesthetics. Our data suggest that exposure of healthcare personnel may exceed recommended levels in poorly ventilated postanesthesia care units.
美国国家职业安全与健康研究所（NIOSH）已确定氧化亚氮的时间加权平均推荐暴露限值为百万分之25（ppm），挥发性麻醉剂的最高限值为2 ppm。我们对麻醉后护理护士呼出麻醉气体的暴露情况进行了量化。本研究在一家中型医院的麻醉后护理单元（PACU）进行。PACU的空气交换平均为每小时8次；然而，其中大部分空气是再循环的。我们评估了50名接受异氟烷（n = 19）或地氟烷（n = 31）麻醉的成年人。大约一半的患者在手术室进行气管插管拔管，而其他患者在进入PACU后立即拔管。通过连接在参与护士肩部（呼吸区）的20米软管对呼出的麻醉气体进行采样。我们还评估了15名接受氧化亚氮麻醉患者恢复期间护理人员对呼出麻醉气体的暴露情况。使用翻领剂量计对暴露情况进行量化。麻醉和恢复持续时间均约为1小时，大多数患者在PACU进行气管插管拔管。接受异氟烷治疗的患者呼吸区麻醉浓度在37%的患者中超过了NIOSH的建议值，占恢复时间的12%。然而，接受地氟烷治疗的患者呼吸区麻醉浓度在87%的患者中超过了NIOSH限值，占恢复时间的49%。总体而言，68%的这些患者检测到不符合规定的情况，占整个恢复持续时间的35%。接受氧化亚氮治疗的患者呼吸区麻醉浓度在53%的患者中超过了NIOSH限值。我们的数据表明，在某些情况下，术后护士对呼出麻醉气体的暴露超过了NIOSH限值。
一些流行病学证据表明，接触废弃麻醉气体可能与生殖毒性有关。因此，美国国家职业安全与健康研究所已确定了氧化亚氮和挥发性麻醉剂的推荐暴露限值。我们的数据表明，在通风不良的麻醉后护理单元中，医护人员的暴露可能超过推荐水平。
