Fomentations are chiefly employed to allay pain or irritation, or to promote suppuration or the healthy action of the parts. As the intention is to convey heat, combined with moisture, to the part fomented, the utmost care must be taken to manage the application so as to promote the object in view as much as possible. Flannel cloths wrung out of the hot or boiling liquid, by means of two sticks, turned in opposite directions, form the best vehicles for fomentations. If they are shaken up, and laid lightly over the part, they involve a considerable quantity of air, which, being a bad conductor, retains the heat in them for a considerable time. “In every process of fomenting there should be two flannels, each (say) three yards long, with the ends sewed together, to admit of the boiling water being wrung out of them; and the one flannel should be got ready whilst the other is applied. The fineness or the coarseness of the flannel is not a matter of indifference. The coarser it is the less readily does it conduct heat, and the longer it retains its warmth; therefore it is more efficient for fomenting. White flannel also retains the heat longer than coloured flannel.” (Dr R. E. Griffith.) More harm than good is frequently done by allowing the patient to become chilled during the application. “If only one (flannel) is used, the
skin becomes chilled during the time occupied in removing the flannel, soaking it in the water, wringing it out, and reapplying it; but if two are used, one of them is ready, and can be applied the moment the other is taken off, by which means the part is never exposed to the air, no matter how long the fomentation is continued. In some diseases (rheumatism, peritonitis, &c.), the patient is scarcely conscious of a degree of heat which scalds the nurse’s hands. In this case the fomenting flannels should be put in a towel, by which means they may be wrung out without being handled by the nurse, and may be applied far hotter than can be done by any other method.” (Dr J. B. Nevins.)
The quantity of liquid forming a fomentation, as well as the size of the cloths employed, must entirely depend upon circumstances. In some cases (as in slight affections of the face, &c.) the application may be effectually made by holding the part in the steam of the hot liquid, and bathing it continually by means of a sponge or cloth. In some instances 1⁄2 pint to a pint of liquid may be found a sufficient quantity; whilst in others several quarts will be required. Under all circumstances, care must be taken to keep the fomentation as near as possible at the temperature ordered, during the whole time of its application; and, as soon as the operation is finished, to quickly wipe the part dry, and to cover it with ample clothing, in order that the reaction set up may not be prematurely checked.
Fomentations usually consist of simple water, or the decoction of some simple vegetable substance, as chamomiles, elder flowers or mallows; but, occasionally, the leaves and flowers of aromatic and narcotic plants, and saline matter, are employed under this form. The following formulæ are given as examples:—
Fomentation, Acetic. Syn. Fotus aceticus (Paris Codex). Fomentations of vinegar are sometimes prepared with white, with rose, or with aromatic vinegar (Paris Codex) in the proportion of one of vinegar to four of water.
Fomentation, An′odyne. Syn. Fotus anodynus, Fomentatio anodyna, Fomentum anodynum, L. Prep. 1. Simple decoction of poppy-heads.
2. (Hosp. F.) Poppy-heads (without the seeds), 11⁄2 oz.; water, 31⁄2 pints; boil to 21⁄2 pints; add of elder flowers, 3⁄4 oz.; boil to a quart and strain. Used to allay pain.
3. (Pierquin.) Opium, 1 oz.; wine, 1 quart; boil to a pint and strain. Used in severe gouty, rheumatic, neuralgic, and syphilitic pains.
4. Opium, 1 oz.; water, 1 quart; boil to 3⁄4 pint, add pyroligneous acid, 2 fl. oz.; boil for 10 minutes longer, then further add of sherry wine, 3⁄4 pint; and as soon as the whole again boils, strain it for use. Superior to the last, and cheaper.
Fomentation, Antineural′gic. Syn. Fomentatio antineuralgica, L. Prep. 1. (Mialhe.) Acetate of morphia, 2 gr.; acetic acid, 2 or 3 drops; eau de Cologne, 2 or 3 dr.; dissolve. In facial neuralgia.