INFLAMMATION OF THE JUGULAR VEIN. 
157 
YI.—phlebitis, inflammation of the jugular 
VEIN (PHLEBITIS YENiE JUGULARIS). 
In former times, when bleeding was much more general, horses and 
cattle frequently exhibited this sequel of the operation. It was described 
as venous fistula, but its nature remained long unrecognised.. Lafosse 
and Hunter had drawn attention to thrombus formation occurring m the 
vein; but until Virchow’s experiments, the relation of this coagulation 
to phlebitis was not understood. The ordinary wound in the vein, caused 
by lancet or fleam, closes by the edges coming together and uniting. 
Apposition is favoured by the negative blood pressure in the jugular, and 
no visible change is usually left in the vessel. The skin wound, if closed 
by pin sutures, commonly heals by first intention. 
Causes of venous fistula; are,—1st, blood coagulating in the vein; ant 
2nd, purulent breaking down or septic softening of the thrombus. The 
following circumstances favour thrombus formation : 
The venous wound, if inflicted by a blunt fleam or lancet, and not 
smoothly cut, but torn through, may be followed by coagulation ot blood 
on the bruised surface and complete thrombosis of the vessel. The same 
occurs if the wound is not made exactly in the longitudinal course o 
the vein, but somewhat obliquely, or when, owing to repeated use o 
the instrument, a double wound has been formed. Injury to a va ve 
in the vein can also induce coagulation, though Hertwig has declared 
that the danger so produced is not great. Venous fistula;, further, arise 
from any circumstance which prevents proper approximation of the 
edoes of the venous wound, and most notably from considerable sub¬ 
cutaneous bleeding. The extravasation displaces the edges of the vesse , 
and the subcutaneous clot extends into the vein. Extensive extravasa¬ 
tions at the point of bleeding are produced by pressure of the collar on 
the unhealed wound, by animals, suffering from staggers, leaning agams 
the manger, by those with disease of the feet continuously lying, or by 
openings being made in the vein, as was formerly done to introduce 
drugs into the blood stream. Viborg, who practised intravenous adminis¬ 
tration of medicines by means of a funnel, had extensive opportunities 
of observing this disease. Unclean (by this we do not mean septic) 
instruments, do not cause phlebitis so frequently as has been supposed. 
The thrombus, howsoever caused, usually undergoes puiu en . ism- 
tegration or septic softening, and induces inflammation in the mtima of 
the vessel, which soon spreads to the media and adventitia, and leads 
to perforation of the walls at different points, producing discharge ot 
the offensive purulent contents. Clotting and subsequent organisation 
seldom occur ; the thrombus usually breaks down. In this case the vein 
is also permanently occluded. Organisation only takes a short time, 
