118 WOUNDS AND BRULSES. 



be complete, fibrin will become deposited above and below the clot, as far as 

 the blood is stagnant, so that the vein will be plugged up by a fibrous deposit 

 or thrombus. Subsequently, circulation in the vein may become more or less 

 restored, or the vein may remain permanently blocked up, in which case, loss 

 of direct circulation through the vessel will be compensated for, in process of 

 time, by the establishment of " collateral circulation," by means of branches 

 of veins which communicate together above and below the wound. When 

 pus (p. 15) forms in the wound, blood-poisoning may take place with or 

 without emhoUsm, which is the term applied to the plugging-up of distant 

 vessels of comparatively small calibre, by broken-oft' particles of the thrombus 

 being carried into the circulation. Such embolism is particularly liable to 

 cause a fatal form of inflammation of the lungs, into which organ the blood 

 that passes through the jugular vein, is carried in order to be pmified before 

 reaching the heart (p. 10 et seq.). Moller states that blood-poisoning from 

 inflammation of the jugular vein is rare. 



SYMPTOMS. — The only cases we need consider here are those 

 ill which the inflammation of the walls of the vein rmis an unhealthy 

 course, with the formation of pus and an extensive clot. The 

 affected portion of the vein is swollen, hard, knotted, and painful 

 to the touch. The surrounding tissues are more or less swollen, 

 and the wound has an unhealthy and inflamed appearance, and 

 discharges dark-coloured blood and pus. Abscesses may form in 

 the clot. Inflammation of the lungs from embolism may be mani' 

 fested by high internal temperature and great diflRculty of breathing. 

 For symptoms of blood-poisoning, see page 532. In favourable 

 cases of blocking up the vein, the establishment of " collateral cir- 

 culation " wdll in time relieve the distressing symptoms of brain 

 disturbance which at first take place, owing to interference with 

 the removal of venous blood from the head. 



We can find out if this vein is in working order by pressing oui' 

 finger on the jugular groove, at about the spot indicated by the 

 .arrow head in Fig. 43. If it be all right, it will be seen to fill with 

 blood, above the finger. 



TREATMENT.— Treat the wound antiseptically (p. 67), after 

 bathing the part with warm water. If any abscesses form, open 

 them freely and treat as directed on page 79. Avoid probing the 

 wound or pressing on the thrombus (clot in the vein), lest embolism 

 (see above) may ensue. Rub in " a smart cantharides blister along 

 the course of the inflamed part, and a cure will be eft'ected in a very 

 short time. The blister is to be applied, whether suppuration be 

 present or otherwise" (Williams). The vein may be tied (ligatured) 

 either below the thrombus or both below and above it, as the case 

 may indicate. The horse should not be made to feed with his 

 head low down, as that w^ould greatly increase the difficulty the 

 blood already has of making its way to the heart. 



