Chapter 47 Thermotherapy

(Includes Hot Packs, Paraffin Wax, Infrared Lamps)

OVERVIEW.

Thermotherapy comprises a number of physical agents that use superficial heat to increase soft tissue extensibility, reduce pain, improve circulation, and accelerate healing. Thermal therapy is believed to accomplish these goals by increasing blood flow (vasodilation), reducing alpha motor neuron firing rate, increasing pain threshold (gating effect; reduced ischemia), and increasing metabolic activity (increasing the availability of oxygen to tissue).¹ Note: Because thermotherapy produces heat, the tissue needs to be capable to dissipating the heat via adequate blood circulation, and the patient must be capable of informing the clinician (or escaping) if the modality gets too hot.

SUMMARY: CONTRAINDICATIONS AND PRECAUTIONS.

Six sources cited a total of 31 concerns for thermotherapy. Concerns ranged from 8 to 18 per source, with a physician citing the largest number. The largest proportion of concerns related to the skin, procedural, and circulatory issues. The most frequently cited concerns were malignancy, hemorrhaging, impaired mentation or sensation, and acute inflammation.

OTHER ISSUES: POSSIBLE PROCEDURAL IRREGULARITIES CONTRIBUTING TO COMPLICATIONS.

(1) Monitoring insulation: In a 1996 California lawsuit,² a 13-year-old girl received a $175,000 arbitration award after she sustained a third-degree arm burn from a hot pack that was inadequately insulated and not periodically monitored. (2) Monitoring excessive treatment: Waldorf et al³ reported on a 46-year-old woman who developed erythema ab igne (hyperpigmentation) from using an electric heating pad 12 hours a day for about 6 weeks. (3) Monitoring paraffin temperatures: The FDA⁴ reports14 incidences of paraffin wax device problems from September 1992 to January 2003. Of these, 10 reports were of wax becoming too hot. Five cases led to hand burns.