Operating Room & Ward
What is an electrosurgical unit?
The electrosurgical unit is one of the most commonly used medical devices in surgery. The electrosurgical unit produces Joule heat by generating electric current to a local area on the body with a high-frequency current. This heat can coagulate a bleeding site or make an incision in the tissue in the body. In addition, surgical operation can be continued by suppressing bleeding. The surgeon, therefore, performs smoothly and decreases the risk to the patient.
You do not get shocked even if you receive a high-frequency current!
There is a concern whether the patient will be shocked when receiving electricity on the living body. In fact, the electricity used in this device is a high-frequency current. This high-frequency current has the characteristic that it does not pass electrical stimulation to the nerves and muscle. Therefore, it can be safely used in patients without electric shock (irritation).
Affixing a patient return electrode on the body for collecting the high-frequency current before surgery
The high-frequency current of the electrosurgical generator travels into the body through the tip of the electrode. To collect the electric current to the generator, one electrode of "palm size" called a "patient return electrode" will be attached. Please imagine the following: this patient return electrode is an expanded version of a gel electrode used for an electrocardiogram.
The part to which the patient return electrode is attached varies according to the maneuver of the surgery. It may commonly be attached to a "part with good muscle tone with blood circulation." The main portions include femoral parts, hips, the abdomen, and the upper arm.
For patients with hair on the part where the electrode is attached, removing (shaving) the hair may be necessary. This is to allow as much of the high-frequency current to be collected by the electrode as possible. By raising the coherency between the skin and the electrode, the current can be collected more efficiently.
Instruments comprising electrosurgical unit
The unit consists of only three instruments, the "main body (generator)," the "tip electrode" and the "patient return electrode."
The tip electrode is used for hemostasis, coagulation and incisions
For a tip electrode generating high-frequency current in the living body, a variety of shapes and lengths are available according to various applications (electrodes suitable for procedures and portions). Generally, various kinds of tip electrodes can be attached to a pen-shaped holder with output switches for coagulation and incision. For medical fields including orthopedics, neurosurgery and otolaryngology, "forceps type electrodes" are used, while for endoscopic surgery, exclusive electrodes are introduced.
History of electrosurgical unit in Senko Medical Instrument Manufacturing
MERA has marketed high-frequency electrosurgical units using the spark gap method that was the previous version for a long time. As for the transistor type electrosurgical unit used in recent years, we have developed many new products over approximately 40 years. Consequently, our products are used in many clinical sites including national/government hospitals, university hospitals, and practitioners.
In addition, receiving opinions or demands from clinical professionals such as physicians, clinical engineers and nurses, we have produced new products introducing new technologies. In recent years, the company has developed a unique complete-concomitant-use model, the "Double type electrosurgical unit," which features two functions of the electrosurgical generator embedded on one unit. We have already marketed the product addressing procedures in heart surgery, esophageal surgery and orthopedics, including procedures where two operators must concomitantly use two electrosurgical generators. Furthermore, we have actively studied and developed various accessories used in the electrosurgical units. Concerning the development of the patient return electrode, Sekisui Plastics Co., Ltd. and the company have jointly developed new products. The patient skin-friendly "SAS Pad Matrix" and "NE Gel Pad" patient return electrodes for adults and children have been marketed in Japan.