Risk factors for burn:
(1) uneven heating of the compress or pack
(2) direct application of the compress to the skin, or the use of a moistened barrier cloth
(3) decreased sensation in the treated area (from diabetes, etc)
(4) altered mental status in the patient
(5) prolonged application of the compress or pack
(6) lack of understanding about the hazards of microwave heating or poor instructions
Heating in a microwave oven is typically uneven. The surface can be much cooler than the interior, causing the person to misjudge the thermal load being applied to the skin.
The risk can be reduced by making sure that the compress or pack is evenly heated. This can be done by
(1) turning, kneading or otherwise changing the orientation of the material while heating
(2) using a 2 stage heating process (place the compress or pack into water that has been heated in the microwave)
The only sure way to avoid a thermal burn is not to use a microwave oven.
