CHAP. LX. How to open a vein, or draw blood from thence.
* 1.1THe first thing is, to seat or place the patient in as good a posture as you can, to wit, in his bed, if he be weak; but in a chair, if strong, yet so, that the light may fall directly upon the vein which you intend to open. Then the Surgeon shall rub the arm with his hand,* 1.2 or a warm linnen cloth, that the blood may flow the more plentifully into the vein: Then he shall binde the vein with a ligature a little above the place appointed to be opened, and he shall draw back the blood upwards towards the ligature from the lower part; and if it be the right arm, he shall take hold thereof with his left hand; but if the left, then with his right hand, pres∣sing the vein in the mean time with his thumb a little below the place where you mean to open it, least it should slip away; and that it may be the more swoln by forcing up the blood: Then with his nail he shall mark or design the place to be opened, and shall anoint it, being so marked, with butter or oil, whereby the skin may be relaxed, and the lancet enter more easily, and there∣fore the section may be the less painful. Hee shall hold his lancet between his thumb and fore-fin∣ger, neither too near, nor too far from the point; he shall rest his other three fingers upon the pa∣tients arm, that so his hand may be the more steddie, and less trembling. Then shall he open the vein with an incision agreeable to the magnitude of the vessel,* 1.3 and the indifferent thickness of the contained blood, somewhat aslant, diligently avoiding the arterie which lies under the Basilica, and the nerve, or tendon of the two-headed muscle, which lies under the Median vein. But for the Cephalick, it may be opened without danger. As much blood as is sufficient being drawn, ac∣cording to the minde of the Physician, he shall loose the ligature, and laying a little bolster under he shall with a ligature binde up the wounded part to stay the bleeding, the ligature shall be nei∣ther too straight,* 1.4 nor loose, but so that the patient may freely bend and extend his arm; where∣fore whilst that is in doing, he must not hold his arm straight out, but gently bended, other∣wise he cannot freely bend it.