Shepherd J P, Jones D C
Department of Oral Medicine and Oral Surgery, University of Bristol Dental School and Hospital, UK.
Int J Oral Maxillofac Surg. 1988 Feb;17(1):4-5. doi: 10.1016/s0901-5027(88)80218-2.
Nitrous oxide concentrations have been measured spectrophotometrically in an out-patient clinic to assess pollution during simulated cryosurgery. Unacceptable levels, in excess of 2,000 ppm, were achieved during freezing and thawing and concentrations decreased only to 400 ppm when simple measures were taken to ventilate the clinic. The apparatus required a flow-rate of 11 l/min. It is concluded that scavenging apparatus should be used during cryosurgery with nitrous oxide if treatment is prolonged. Liquid nitrogen systems are preferable if excellent ventilation and scavenging apparatus are not available.
在一家门诊诊所中，已采用分光光度法测量了一氧化二氮浓度，以评估模拟冷冻手术期间的污染情况。在冷冻和解冻过程中，一氧化二氮浓度达到了超过2000 ppm的不可接受水平，而在采取简单的诊所通风措施后，浓度仅降至400 ppm。该设备需要11升/分钟的流速。得出的结论是，如果治疗时间延长，在使用一氧化二氮进行冷冻手术期间应使用清除设备。如果没有良好的通风和清除设备，液氮系统则更为可取。
