Efficacy of electrocoagulation hemostasis: a study on the optimal usage of the very-low-voltage mode

The very-low-voltage (VLV) mode in electrosurgery can stably and deeply energize tissues even if the local electrical resistance changes with energization. Therefore, in electrosurgical hemostasis, the VLV mode is more reliable than other coagulation modes. In clinical practice, the appropriate use of combined saline drip and blood suction under the VLV mode can further enhance coagulation ability. However, the detailed mechanism is not known. The current study aimed to evaluate the association between electrosurgical activation time (ET) and hemostatic tissue effect (HTE) under the VLV mode. Further, the effect of saline drip and suction on power consumption and HTE was validated.

Twelve female pigs weighing 35 kg were included in the experiment. A liver hemorrhage model was established via an open abdominal procedure, and hemostasis in the hemorrhagic lesion was attempted using the VLV mode under different conditions (ET: 3, 6, 9, and 12 s, with/without saline drip and/or continuous suction). Electrical data (such as voltage, current, and resistance) during coagulation were extracted. Then, the vertical/horizontal extent of HTE was assessed, and the hemostasis outcome (successful or failed) was recorded.

The vertical/horizontal HTE, power consumption, and integrated current value were positively correlated with the ET. The coagulation depth deepened with saline drip (p < 0.01). However, it was not affected by continuous suction (p = 0.20). The HTE area increased with saline drip (p < 0.01) and decreased with suction (p < 0.01). The power consumption and integrated current increased with saline drip (p < 0.01) and decreased with suction (p < 0.01). The success rate of hemostasis decreased with saline drip alone (31of 48 trials [success rate = 64.5%] in the saline drip group and 44/48 trials (success rate = 91.7%) in the control group). However, it improved with continuous suction (46/48 trials [success rate = 95.8%]).

The electrosurgical activation time was positively correlated with hemostatic tissue effect. Saline drip increased heat transfer efficiency but decreased the success rate of hemostasis. Therefore, the use of continuous suction in addition to saline drip increased hemostatic efficiency.