FROM MY PT SCHOOL NOTES · MODALITIES · UNIT 2 · CHAPTER 06
What Is Different About Heat and Cold?
The method of energy transfer and the patient’s tissue status shape the response.
At a glance
CONDUCTION
Skin contact
CONVECTION
Moving water or air
EVAPORATION
Liquid to vapor
What matters most
- Conduction moves heat through contact, convection through moving fluid or air, radiation without contact, and evaporation removes heat as liquid vaporizes.
- A pack’s effect varies with interface, insulation, skin condition, perfusion, body area and patient sensation.
- Comfort and short-term symptom changes should support an active task, not replace it.
Safety and evidence limits
Screen impaired sensation/circulation, fragile skin, hypersensitivity to cold, recent injury and suspected bleeding. There is no single safe duration for all people.
Try a clinical decision
Scenario: A newly injured, swollen ankle is painful. Should heat be applied because the patient requests it?
Reveal the reasoning
Clarify trauma and fracture concerns, skin/neurovascular status, bleeding and the goal. Do not let preference bypass assessment; choose symptom support only when appropriate.
My original class sources: 7-8 thermal agents.pdf; Themal agents Cheat sheet.pdf; Hot Pack positioning.pdf. Supplementary context is not part of the original lecture packet. Educational summary, not a clinical protocol or device-setting guide.
