There are two types of burns caused by high-frequency electrosurgery. One type occurs at the electrode plate, which is called plate burn; the other type does not occur at the electrode plate, which is called non-plate burn.
Causes of plate burns
The current density at the electrode plate is too high, and when the actual contact area between the electrode plate and the patient is too small, plate burns are likely to occur. The main types of electrode plates are: ① Metal electrode plates: The electrode plates are hard and have poor compliance. During the operation, the gravity of the patient's body presses the electrode plates. When the patient moves, it is difficult to ensure the effective contact area of the electrode plates and burns are prone to occur. ② Conductive glue electrode plate: When using, coat the electrode plate with conductive paste and place it in a suitable location. When the conductive glue on the negative plate loses water and dries out or is attached to a moist area on the skin, it may burn the patient. ③ Disposable adhesive electrode plate: It has the characteristics of good compliance and strong adhesiveness, which can ensure the contact area of the patient during the operation. At the same time, the resistance of the electrode plate is 0, the thermal effect is low, and the risk of burns is small. It is often used clinically.
Causes of non-plate burns
① High-frequency radiation, if carried by the patient or in physical contact with metal objects, can cause serious high-frequency radiation phenomena and burn the patient. ② If the circuit is self-short-circuited, if each circuit is not checked to see if it is intact before use, if the surface organic matter is not removed in time when using a hard plate, and if there is no dedicated person to perform regular maintenance, the circuit short-circuit may cause burns to the patient. ③ Low-frequency sparks. Commonly seen are the low-frequency currents generated by sparks when the cutter head cable is disconnected, which is extremely harmful because it causes burns not on the body surface but on the heart. In addition, the electric knife should not be started and burned too frequently like raindrops, because such sparks will also cause certain low-frequency burns. ④Electric cautery encounters flammable liquids: The electric knife will produce sparks during surgery, and flammable liquids will burn when exposed to fire or arc light. The operating room uses iodine and alcohol to disinfect the skin of the surgical field. There is too much alcohol in the disinfecting gauze. If the sterile cloth is soaked or there is too much residual alcohol from surgery, the alcohol volatile liquid will be burned when the electrosurgery is started, causing skin burns.
Prevention and care measures for electrical burns
1) Metal objects are not allowed into the operating room
Patients are not allowed to bring any gold or silver jewelry into the operating room. Although these metal objects are not completely grounded, they can cause high-frequency radiation. When using other monitoring electrodes and other probes during the operation, interference between instruments should be avoided as much as possible.
2) Use the negative plate correctly
Proper use of negative plates is an important factor in preventing electrical burns. Therefore, the performance of the electrosurgery and the condition of the negative electrode plate should be carefully checked before starting the operation. It is best to use soft electrode plates. When pasting the negative plate, please pay attention to: ① Place it on a place with rich muscles, such as the buttocks, thighs, and calves. Do not stick it on hair, fat, scars, joints, and bony protrusions, and do not press it under the patient's body. ② Paste the negative plate as close to the surgical area as possible, and fix it firmly to prevent loosening. At the same time, keep the negative plate flat and in complete contact with the skin. The contact area is not less than 64.5 cm [1]. Avoid local pressure with hard objects. ③If the patient is found to be restless during the operation, the position of the negative plate and the condition of the limbs should be checked promptly. If the negative plate is out of position, the machine should be shut down and replaced.