Smith J P, Topmiller J L, Shulman S
National Institute for Occupational Safety and Health, Cincinnati, Ohio 45226.
Lasers Surg Med. 1990;10(3):224-33. doi: 10.1002/lsm.1900100303.
Gaseous and particulate emissions from laser surgery are often controlled by the use of smoke evacuators. Thus it is important that factors affecting the performance of these evacuators be understood. In this study, a tracer gas technique was used to examine a number of factors affecting the performance of smoke evacuators, including evacuator flow rate, distance from the evacuator nozzle to the surgical site, and direction and speed of external air flow in relation to nozzle flow. The tracer gas technique allowed the release of emissions to be visualized with infrared imaging and also allowed the collection efficiency to be assessed quantitatively. The results were demonstrated with the use of a surgical laser system. It was found that the collection efficiency of the smoke evacuator was affected by all the factors studied. Increasing the evacuator flow rate allowed the collection of emissions under conditions in which lower evacuator flow rates had less efficient collection. The speed and direction of external air flow affected collection of emissions greatly. If the air flow was in the same direction as the nozzle flow, efficient collection of emissions at a distance from the emission release point was observed. However, at other angles relative to nozzle flow, the efficiency degraded rapidly with distance from the emission release site. With the use of the surgical laser system, at laser powers of 30 W, the tracer system predicted the collection of emissions. At 60 and 100 W of laser power, higher external air flows and greater attention to nozzle positioning were necessary. Based on the results of this study, conclusions are drawn on how to improve the collection efficiency of smoke evacuators used in laser surgery.
激光手术产生的气态和颗粒排放物通常通过使用烟雾抽吸器来控制。因此，了解影响这些抽吸器性能的因素很重要。在本研究中，采用示踪气体技术来研究影响烟雾抽吸器性能的多个因素，包括抽吸器流速、抽吸器喷嘴到手术部位的距离，以及外部气流相对于喷嘴气流的方向和速度。示踪气体技术使排放物的释放能够通过红外成像可视化，还能定量评估收集效率。结果通过使用手术激光系统进行了展示。发现烟雾抽吸器的收集效率受到所研究的所有因素的影响。提高抽吸器流速能在较低流速收集效率较低的条件下实现排放物的收集。外部气流的速度和方向对排放物的收集有很大影响。如果气流与喷嘴气流方向相同，在离排放点一定距离处能观察到高效的排放物收集。然而，相对于喷嘴气流的其他角度，效率会随着离排放点距离的增加而迅速下降。使用手术激光系统时，在30瓦的激光功率下，示踪系统能预测排放物的收集情况。在60瓦和100瓦的激光功率下，则需要更高的外部气流以及更注意喷嘴的定位。基于本研究结果，得出了关于如何提高激光手术中使用的烟雾抽吸器收集效率的结论。
