Blended currents allow the surgeon to cleanly divide tissue while maintaining a variable degree of hemostasis, depending on the amount of coagulating current used. Blended currents are created by modulating a second, lower frequency, higher amplitude sine wave with the sine wave from the cutting generator, producing a higher peak-to-peak voltage. The new waveform is then delivered in intermittent bursts at a rate determined by the settings of the electrosurgical generator (i.e., Blend 1) (Fig. 1). This burst effect, although delivered at higher peak-to-peak voltage, contains a lower average power than a pure sinusoidal waveform because of the duty cycle.
Fig. 1. Blended current: A combination of cutting and coagulation currents.
A second form of time varying current is produced by the process of rectification, in which an alternating current is modified so that it becomes unidirectional. This may be done by either blocking the portion of the wave with a negative polarity (half wave or partial rectification) or by reversing the negative portion of the wave (full wave rectification). The current is time varying because its flow is not constant, even though its polarity does not change. Rectified currents are commonly used in dental and dermatologic surgery.
Jinhua Huacheng Medical Appliance Co.,Ltd.
Manufactuer of disposable medical products: Electrosurgical pencil,grounding plate,skin stapler and ECG electrode
