HYDROCOLLATOR Sekar.L

INTRODUCTION  The use of moist heat as a therapeutic agent is one of the oldest forms of medicine.  Commercial hot packs is one of the most common ways to deliver superficial moist heat.  The heating unit is called a HYDROCOLLATOR UNIT

THE HYDROCOLLATOR UNIT  The hydro-collator unit is a stainless steel tank in which silica gel packs or BENTONITE crystal packs are heated.  The capacities of the machines vary, and all units have insulated bases, the larger machines being insulated with fiberglass.  The units contain a wire rack which acts as divider for the packs and prevents contact of packs with the bottom of the tank.

 These packs are stored in thermostatically controlled and maintains water in the unit at a temperature between 70°C and 80°C.  It can be left on continuously as long as there is enough water in the tank.

A Hydro collator Pack  A hydrocollator pack is good in any situation that requires penetrating heat.  A hydro collator pack is a fabric envelope containing silica gel.  The main property of the gel is its capability to absorb many times its own volume of water, provides a considerable store of heat energy.

 These packs are heated in a hydro- collator unit.  It give moist heat for 30 to 40 minutes  Packs come in various sizes and shapes  A special collar pattern pack for the neck is usually available.

 The packs are wrapped in:  Turkish towels – 6- 8 layers of toweling  Special / commercial terry cloth blankets  Large packs may be wrapped in bath blankets.  The packs last about six months.  When they begin to wear out the filler leaks out and makes the water cloudy; they should then be replaced.

 The pack is applied to the body after being wrapped adequately in toweling or blankets. (This provides THERMAL INSULATION, So that the pack is at above 75˚C & the skin temperature does not rise above 42˚C or so).

 Care must be taken to have a layer of toweling and to avoid excessive pressure by weight being placed on bony points.  The part selected to be treated must be able to tolerate the pressure of the pack (approximately 500 to 800 grams) and to tolerate a 7° C to 10°C rise in temperature.  But after 10 min of the treatment the patient may regard the pack as cool & comfortable.  Nevertheless the rise in temperature of the region under the pack averages 5˚C.

Biological Effects of Hydro-collator Packs 1.HEAT PRODUCTION is subject to the quantity & depth of penetration 2.Temperature elevation is depend upon the patency of circulation, sensation & the ability of the tissues to dissipate heat 3.Skin tolerance to heat is 44˚C. (Temperature of over 45˚C over 5 to 10 min will cause a BURN. Safe & effective application of heat is 44˚C for 20 – 30 min.)

4. SKIN TEMPERATURE – INITIAL RISE BY 7 MIN – MAX 7 - 8˚c. (It drops of about 2˚C over 20 – 30 min) 5. THE SUBCUTANEOUS TISSUE – The temperature rise of about 3˚C in about 20 min. 6. THE MUSCLE TEMPERATURE – The temperature rise of about 1 - 2˚C by 30 min. 7. HYPERAEMIA – Increased vasodilation 8. SEDATIVE EFFECT – Moist heat is a safe analgesic & a muscle relaxant. 9. METABOLIC EFFECT – Increase in tissue metabolism.

Indications for Hydrocollator Packs 1.PAIN & MUSCLE SPASM 2. Inflammation. 3. Edema. 4. Adhesions.

Contra-indications for Hydrocollator Packs: 1.Impaired Skin Sensation 2.Circulatory dysfunction 3.Analgesic drugs 4.Infections and open wounds 5.Cancer and Tuberculosis 6.Gross Oedema 7.Lack of Comprehension 8.Deep X-Ray Therapy 9.Liniment

Advantages: 1.A hydro-collator pack is easy to apply 2.The packs are of various sizes which fit most clinical needs. 3.Moist heat has a more sedative effect than dry heat. 4.low cost, minimal maintenance, long life

5. Maximal temperatures are more uniform than in electrically-heated pads. 6. The patient does not need much handling. 7. The pads can be laid out ready for the patient to place on the affected part.

Disadvantages: 1.A hydro-collator pack is not easily applied around shoulders and hips. 2.It is somewhat heavy and should not be used on extremely sensitive patients, since it can create discomfort. 3.Sometimes moist packs have a tendency to cause a skin rash.

DANGERS & PRECAUTION  1. BURNS – May occur due to; a)Insufficient toweling b)The temperature of the pack could be too high c)Impaired circulation  2. DEHYDRATION – Excessive sweating may produce dehydration

CARE OF THE HYDROCOLLATOR UNIT  1. The water level should be kept up to 3/4 th full of water or slightly over the top of the packs at all times  2. The unit should be cleaned periodically

APPLICATION  Remove the pack from the unit & place it on the towel.  Fold another towel into 4 – 6 layers & place it over the pack.  Wrap the whole pack up with the bottom towel.  The temperature of the wrapped pack should not exceed the 44˚C

 Monitor the initial response from the patient to treatment during the first 5 to 10 min by asking the patient for feedback & by visually inspecting the skin.  If necessary, adjust the layers of toweling.  During the treatment maintain the position of hot pack & ensure that it does not exacerbate pain, produce discomfort or occlude circulation.