CHAPTER VIII. 
VEINS. 
I. 
TRAUMATIC LESIONS. 
LVon-penetrating wounds of veins are, ordinarily, not serious. Punctures. 
and cuts cicatrize almost always rapidly. Bruises and denudations are 
sometimes accompanied with thrombosis, phlebitis or escharrification of the 
venous walls and then secondary hemorrhages. 
Penetrating wounds are made by puncturing, cutting or bruising objects. 
Fricks of veins, either by operations or accident, give rise to a more or 
less abundant flow of blood, varying with the size, of the perforation. 
When the cutaneous opening is small, the blood becomes infiltrated in the 
perivenous connective tissue and in the cellular sheath of the vessel; an 
hemostatic thrombus is formed. Wounds with sharp instruments are 
complete or incomplete. Incomplete, they are longitudinal, oblique or 
transverse ; it is with them that hemorrhage is persistent. Complete 
sections are immediately followed by a double longitudinal and circular 
retraction of the ends of the vessel, but nevertheless the hemorrhage is. 
always abundant. In some cases, the central end bleeds little; in others 
the hemorrhage is great, as when a collateral branch opens between the 
‘wound and the first valve of the injured vessel. Transverse wounds of 
veins may rapidly prove fatal, specially when the circular retraction of the 
ends is prevented by adhesion of the vessels to the surrounding organs 
‘(aponeurosis, bones) or by diseases of their own structure. Contused 
wounds have their edges either clean or irregular and ragged. The 
hemorrhage is light and of short duration. Consecutive phenomena are the 
same as in the preceding wounds; however, they are followed more fre- 
quently with diffuse phlebitis, partial sloughing and secondary hemorrhage. 
When there is swdcutaneous wounds, the blood collects in the peri- 
venous tissues, sometimes filtrates along the length of the vessel, in the 
musculo-aponeurotic spaces, where it coagulates. 
Wounds of veins whose walls have undergone no pathological alteration 
have a tendency towards cicatrization. In incomplete solutions of con- 
tinuity, temporary homostasis is made by a claviform clot which spreads 
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