What Surgical Functions Are Performed by the Diathermy Machine?
A diathermy machine used in surgery (electrosurgical unit/“electrocautery” equipment) can perform tissue effects primarily in two ways: (1) cutting (vaporizing cells with continuous/low-voltage spark-free energy), (2) coagulation (causing protein denaturation with interrupted/low-duty energy), and (3) fulguration (superficial coagulation via spark gap on the tissue surface). In standard surgical electrosurgery classifications, the machine’s surgical functions include cutting, coagulation, and fulguration—not only a subset.
This corresponds to option (iv) cutting, coagulation, fulguration.
Key terms: diathermy electrosurgery cutting coagulation fulguration.
Note: The multiple-choice options imply different combinations of these electrosurgical modes. The comprehensive set used in surgery is cutting + coagulation + fulguration.
Electrosurgery Modes: Cutting vs Coagulation vs Fulguration
Surgical electrosurgery: mapping modes to functions
Different “modes” of electrosurgery change how electrical energy is delivered to tissue, which in turn determines the predominant tissue effect:
- Cutting: The electrode transfers energy in a way that primarily vaporizes intracellular/extracellular water, producing a true incision.
- Coagulation: The energy delivery is altered so that thermal injury predominates without the same degree of vaporization, leading to hemostasis by protein denaturation and microvascular sealing.
- Fulguration: The active electrode is positioned to create a spark at/near the tissue surface, producing superficial coagulation (useful for small bleeding points or superficial lesions).
Mermaid concept map of cause → effect:
Therefore, the correct option is (iv) cutting, coagulation, fulguration.
Exam strategy
If a question lists cutting, coagulation, and fulguration as choices, the “diathermy/electrosurgical unit” in standard surgical teaching is associated with all three—so pick the option that includes (iv).
Beware terminology confusion
In practice, some clinicians use overlapping everyday terms (e.g., “cautery”)—but electrosurgical textbooks commonly distinguish cutting, coagulation, and fulguration as distinct functions/modes.
How to identify the correct option from the list
- 1Step 1
Extract the three effects: cutting, coagulation, and fulguration.
- 2Step 2
Standard surgical electrosurgery teaching attributes these three distinct tissue effects to the electrosurgical (diathermy) unit.
- 3Step 3
Only choice (iv) includes all three: cutting + coagulation + fulguration.
- 4Step 4
Choose (iv).
Core electrosurgery functions
Incision creation
CuttingPrimary effect: tissue vaporization → incision."
Hemostasis
CoagulationPrimary effect: protein denaturation → bleeding control."
Superficial surface coagulation
FulgurationPrimary effect: spark-mediated superficial coagulation."
Which functions are included in each option?
Presence of cutting/coagulation/fulguration in the given choices.
Quick clarification of each function
Diathermy / Electrosurgery mode flashcards
Knowledge Check
Which surgical functions can a diathermy machine perform (electrosurgical unit modes)?