1008 SURGICAL AXATOMY OF THE ARTERIES. 



hands of different surgeons, and even in the hands of the same surgeon in 

 different cases.* 



The principal facts bearing on the actual performance of an operation on 

 the third part of the subclaviau artery, will now be briefly recalled. The 

 most prominent or convex part of the clavicle, the part of the bone opposite 

 which the vessel lies, will serve as a guide for the middle of the first incision, 

 which is to be made a little above the clavicle, and parallel with it. If 

 (after noting with the eye, or marking on the surface the line at which it is 

 desired to make the incision), the integument be drawn downwards over the 

 clavicle, the parts covering the bone may be divided with freedom. 



With the integument, the platysma and several nerves are divided in thi^t 

 incision, but no vessel is endangered, except in those rare cases in which the 

 cephalic vein or the external jugular crosses over the clavicle [plate 25, 

 figs. 4, 5]. It will, in most cases, be an advantage to add a short vertical 

 incision, directed downwards to the middle of the horizontal one. Should 

 the sterno-mastoid muscle be broad at its lower end, or should the interval 

 between that muscle and the trapezius be insufficient for the farther steps of 

 the operation, a portion of the former muscle, or even of both muscles, must 

 be divided [plate 25, fig. 7]. 



The external jugular vein next presents itself with the veins joining it 

 from the shoulder, and, as this vein is usually over the artery, it must be 

 held aside, or it may be necessary to divide it. If divided, the lower end of 

 the vessel requires the application of a ligature as well as the upper one, iti 

 consequence of the reflux of blood from the subclaviau vein. The omo-hyoid 

 muscle will be turned aside if necessary ; and now must be determined the 

 exact position at which the artery is to be sought by division of the deeper 

 fascia. If the clavicle have its usual horizontal direction, the first rib is the 

 best guide to the vessel. The brachial nerves are here, it is to be remem- 

 bered, close to the vessel, so much so, that the ligature has in several 

 cases been passed in the first instance round one of them instead of the 

 artery. But if, in consequence of the disease rendering the operation neces- 

 sary, the outer end of the clavicle be much raised, then it will, in many 

 cases, be more easy to place the ligature on the artery above the insertion of 

 the scalenus muscle, or even behind that muscle. Above the first rib, the 

 situation of the vessel may be ascertained by means of the brachial nerves 

 and the scalenus muscle ; and, before the membrane covering them is 

 divided, the position of these structures may be ascertained by the difference 

 they offer to the touch. The cord-like nerves and the smooth flat muscle 

 may thus be readily distinguished. At the same time the influence of 

 pressure at a particular point in controlling the pulsation in the aneurism, 

 will in this, as in other operations on the arteries, assist the surgeon. 



* This statement will be illustrated by reference to two cases which, occurred at nearly 

 the same time in the practice of the same surgeon. In March, 1819, M. Dupuytren tied 

 the subclaviau artery for axillary aneurism, and the result was in all respects favourable. 

 See "Le9ons orales," &c., t. iv.; and M. Marx in "Repert. general d'anatoinie," &c. 

 1826. 



Two or three weeks afterwards the same surgeon, being engaged in performing an 

 operation of the same kind, was compelled to discontinue it for a time in consequence of 

 the sufferings of the patient, and an hour and forty-eight minutes elapsed before the 

 operation was concluded. The patient died of haemorrhage in four days ; and, on exami- 

 nation after death, it was found that the artery had been perforated with the aneurism 

 needle. One of the large nerves and half the artery had been included in the ligature. 

 This case is reported by Dr. Rutherford, R.N., who was present at the operation, in 

 "Edinburgh Med. and Surg. Journal," vol. xvi. 1820. 



