Page 197 - ASOP ROT Study Guide

The principles are the same for both techniques. The cast should be cut from top to bottom down
to the skin through the cast and the padding. Preferably, all casts should be cut in this manner on
either side, so that the cast is cut in half (bi-valving). This is especially important with resin
casting materials, as they are too strong and springy to be pried apart to remove them without risk
of them springing back and nipping the patient.

When using hand cutters, be aware that they are designed to be used so that the lower jaw remains
parallel to the skin at all times and does not dig in.

Power cutters work by vibrating a saw toothed disc - it does not rotate. In plaster of Paris casts,
the vibration breaks up the plaster of Paris and only partly cuts it. In resin casts the vibrating saw
must cut the material. This generates a great deal of heat which rapidly warms up the saw blade to
dangerous levels. The saw should be stopped frequently and constantly rotated to dissipate heat.
The saw should not come in contact with the skin. The vibrating blade is designed not to cut skin
by ensuring the skin merely vibrates with the blade. However, it will cut skin over bony points
and, if pressed heavily, can cut as well as burn. Power cutters do not cut a cast efficiently at the
upper and lower margins where the material is more flexible and tends to vibrate with the blade.
Manual cutting should be used at the margins. When power cutters are used, under cast padding
should be cut with blunt nosed scissors.

[Note: More litigation occurs over cast removal than cast application.]

4.2 Indenting

If a cast is only split partially and pried there is a risk of it indenting the skin where it has to give
way. This is avoided by bi-valving the cast.

4.3 Penetration by Instruments

Once split it may be necessary to insert a spreading instrument to prize the cast apart. These
instruments may penetrate the skin if not used carefully.

4.4 Dust

Plaster of Paris dust has not been shown to be an industrial hazard and resin alone may also be
thought of as relatively safe. However, glass fiber is a known industrial hazard. The long term
effects of inhaling resin impregnated glass fiber remain unknown. It is prudent to avoid any dust
hazard as a part of good working practice. Power cutting should be carried out using a saw with a
dust extractor. Alternatives are to use hand cutting, which generates large heavy particles, or to
use a face mask.

4.5 Noise

Noise can be very frightening for children and silenced saws may be obtained. Sawing is generally
quicker and less traumatic than hand cutting once it can be demonstrated to the child's satisfaction
that, if used properly, the saw will not cut them. The noise levels for regular users are probably
unacceptable and ear protectors are recommended.