Heater probe (Olympus Key med) – it is a contact method of thermocoagulation. The probe is placed directly on the ulcer at the site visible vessel to maximize the energy delivered to the target and minimize scatter injury.
- Haemostasis is achieved by a special heat-generating device built into the tip of the probe. Special coating on the probe tip prevents it adhering to the mucosa.
- The heater can be used tangentially and en face.
- The heater probe automatically adjusts the duration of an energy burst, according to tissue resistance, to deliver a preset amount of energy. After several probe pulses, the probe is used to irrigate the bleeding lesion to clear the endoscopic field and to gauge the therapeutic effect. Effective haemostasis is suggested by whitening of the lesion and flattening of a nonbleeding visible vessel or clot remnant.
- Water for irrigation and cleansing the target tissue passes through a central port and is delivered from the probe tip. A foot pedal controls coagulation and irrigation.
- The heater probe comes with its own power unit. The large heater probe has a 3.2 mm diameter. A relatively low power setting is recommended for slow and improved control during thermocoagulation with a heater probe. In UGIB, the heater probe is often applied at a power setting of 30 J.
- The mechanism of tissue coagulation is heat transfer. Thus, heater probe can potentially produce deep tissue injury even after tissue desiccation because it has a ceramic tip unlike Gold probe where tissue dessication limits deep energy penetration and injury.
