Townsend Nicole T, Jones Edward L, Paniccia Alessandro, Vandervelde Joel, McHenry Jennifer R, Robinson Thomas N
*Department of Surgery, University of Colorado School of Medicine, Aurora §Covidien, Boulder, CO †Department of Surgery, The Ohio State University, Columbus, OH ‡University of Kansas School of Medicine, Kansas City, KS.
Surg Laparosc Endosc Percutan Tech. 2015 Apr;25(2):111-3. doi: 10.1097/SLE.0000000000000137.
Unintended thermal injury from patient monitoring devices (eg, electrocardiogram pads, neuromonitoring leads) results in third-degree burns. A mechanism for these injuries is not clear. The monopolar "bovie" emits radiofrequency energy that transfers to nearby, nonelectrically active cables or wires without direct contact by capacitive and antenna coupling. The purpose of this study was to determine if, and to what extent, radiofrequency energy couples to common patient monitoring devices.
In an ex vivo porcine model, monopolar radiofrequency energy was delivered to a handheld "bovie" pencil. Nonelectrically active neuromonitoring and cardiac-monitoring leads were placed in proximity to the monopolar pencil and its cord. Temperature changes of tissue touched by the monitoring lead were measured using a thermal camera immediately after a 5-second activation. The energy-device cords were then separated by 15 cm, the power was reduced from 30 W coag to 15 W coag and different cord angulation was tested. An advanced bipolar device, a plasma-based device, and an ultrasonic device were also tested at standard settings.
The neuromonitoring lead increased tissue temperature at the insertion site by 39 ± 13°C (P<0.001) creating visible char at the skin. The electrocardiogram lead raised tissue temperature by 1.3 ± 0.5°C (P<0.001). Decreasing generator power from 30 W to 15 W and separating the bovie cord from the neuromonitoring cord by 15 cm significantly reduced the temperature change (39 ± 13°C vs. 26±5°C; P<0.001 and 39 ± 13°C vs. 10 ± 5°C; P<0.001, respectively). Lastly, monopolar energy increased tissue temperatures significantly more than argon beam energy (34 ± 15°C), advanced bipolar energy (0.2 ± 0.4°C), and ultrasonic energy (0 ± 0.3°C) (all P<0.001).
Stray energy couples to commonly used patient monitoring devices resulting in potentially significant thermal injury. The handheld bovie cord transfers energy via antenna coupling to neuromonitoring leads that can raise tissue temperatures over 100°F (39°C) using standard settings. The most effective ways to decrease this energy coupling is to reduce generator power, increase the separation between wires, or utilize lower voltage energy devices such as ultrasonic or bipolar energy.
患者监测设备（如心电图电极片、神经监测导联）导致的意外热损伤会造成三度烧伤。这些损伤的机制尚不清楚。单极“博维电刀”会发射射频能量，该能量通过电容耦合和天线耦合传递到附近无电活性的电缆或电线，而无需直接接触。本研究的目的是确定射频能量是否以及在何种程度上与常见的患者监测设备耦合。
在一个离体猪模型中，将单极射频能量施加到手持式“博维电刀”笔上。将无电活性的神经监测导联和心脏监测导联放置在靠近单极笔及其电线的位置。在激活5秒后，立即使用热成像仪测量监测导联接触的组织的温度变化。然后将能量设备的电线分开15厘米，将功率从30瓦凝固功率降低到15瓦凝固功率，并测试不同的电线角度。还在标准设置下测试了一种先进的双极设备、一种基于等离子体的设备和一种超声设备。
神经监测导联使插入部位的组织温度升高了39±13°C（P<0.001），在皮肤上形成了可见的焦痂。心电图导联使组织温度升高了1.3±0.5°C（P<0.001）。将发生器功率从30瓦降低到15瓦，并将博维电刀的电线与神经监测电线分开15厘米，显著降低了温度变化（分别为39±13°C对26±5°C；P<0.001和39±13°C对10±5°C；P<0.001）。最后，单极能量使组织温度升高的幅度明显大于氩束能量（34±15°C）、先进双极能量（0.2±0.4°C）和超声能量（0±0.3°C）（所有P<0.001）。
杂散能量与常用的患者监测设备耦合，导致潜在的严重热损伤。手持式博维电刀的电线通过天线耦合将能量传递到神经监测导联，使用标准设置时可使组织温度升高超过100°F（39°C）。减少这种能量耦合的最有效方法是降低发生器功率、增加电线之间的距离或使用低电压能量设备，如超声或双极能量设备。
