When the vein at the bend of the arm is the ves sel selected, the patient should stand, sit, or lie, ac cording to the effects to be produced. If the in tention of the surgeon is to produce fainting at the least expense of blood, as in luxation or rupture, the patient should be held in the erect position, and a large orifice made in the vein in order to remove the fluid quickly. In inflammation of the bowels, the object should be to abstract as much blood as to cause syncope, but not hurriedly, the patient therefore should be placed in the sitting or hori zontal attitude, and a large wound of the vein made. Daring pregnancy we occasionally abstract blood, in order to relieve congestion, and have then to guard particularly against producing syncope or any uterine irritation ; we therefore place the pa tient in the horizontal posture, and make a very small wound.
When a vein at the bend of the arm is to be opened, as represented in Fig. 4 of Plate DXVII, the patient must hold it on the stretch, and have something to grasp in his hand, to keep his fingers in motion, to promote the flow of the blood. The skin must be firmly stretched upwards along the vein, in order to prevent the wounds made in the skin and vein from shifting ; and this is generally done with a fillet or bandage, which should encircle the arm twice, as close as possible to the point to be wounded, and be tied with a slipping knot on the outside of tire arm. The surgeon then places the fore and middle fingers of' his left hand as in ante riotomy, in order to keep the vessel steady, and with his right hand holding the lancet somewhat like a writing pen, he wounds or pricks the skin and vein at once, and gradually cuts obliquely upwards; making the wound in the skin somewhat larger than that of the vein. The blood should flow at the side of the lancet before it is withdrawn ; and when the necessary quantity has been removed, the fillet should be unbound, and tire vein compressed be neath or distad to the wound with the thumb of the left hand, the arm washed with tepid water, the lips of the wound neatly approximated, and a square compress of linen applied, and then bound up with a bandage rolled round the elbow joint in the figure of 8. The Ivonnd should not be dressed sooner than the third day, and then treated according to appearanceA, eit.M•r with it new compress and ban dage, adhesive ',las' Pr, or simple ointment. It not frequently happens, that although the vein is com pressed disrad to the wound, the blood still flows, which arises from an inosculation with one of the deep-seated veins.
However simple this elegant little operation of venesection at the bend of the arm may appear, yet there ::re instances of individuals losing their lives, even in skilful hands, in consequence of a high division of the brachial artery into the radial and ulnae, one of which sometimes runs immedi ately beneath the skin, between it and the fascia of the biceps, and is thus liable to be wounded. A careless operator may transfix the vein and wound the fascia of the biceps or the brachial artery, and thus varicose and false aneurism may be produced: or extensive inflammation of the fascia of the arm, together with suppuration beneath it. Besides these formidable diseases, there are ecchymosis, in flammation of the veia, of the skin, of the cellular substance, of the lymphatics, and the wound of a nerve, which may all occur after venesection at the bend of the arm.
Ecchymo4s, from exxvo,, to pour out, is an effusion of the blood into the cellular tissue, contiguous to the wound in the vein, occasioned by the wound in the skin not corresponding with that in the vein, or the wound of the one not being kept in apposition to that of the other during the flow of the blood, or from the integuments overlapping the wound in the vein, the skin not having been braced with sufficient firmness by the bandage ; or lastly, by not making the wound in the skin a trifle larger than that in the vein. When the blood forms a circumscribed tumour, it is termed a thrombus,from apopCsc, coagu lated blood. The one, therefore, is a circumscribed tumour, and the other a diffused effusion of blood; they both require the same treatment, and unless the quantity of blood be profuse, either effusion is of little consequence, and requires no attention. If however the effusion be extensive and produce pain or inflammation, poultices should be applied and continued until all inflammatory tendency has subsided. The inflammation induced, seldom or never ends in suppuration, even of the lips of the wound. If the ecchymosed fluid does not disappear, and the lips of the orifice arc healed, but not other wise, it may be discussed by exciting absorption by means of stimulant embrocations. All surgical operations are followed by more or less ecchymosis, according as the parts may have been torn or bruised during the operation; but it even supervenes in a slight degree in operations most scientifically performed, especially in the face and other delicate parts of the body, as the knife cuts on the principle of a saw.