Chapter 11- Veins and Lymphatics Flashcards
What together account for at least 90% of
clinical venous disease?
- Varicose veins and
- phlebothrombosis/thrombophlebitis
What are Varicose veins?
abnormally dilated, tortuous veins produced by prolonged, increased intraluminal pressure and loss of vessel wall support.
What veins are typically involved in varicose veins?
The superficial veins of the upper and
lower leg are typically involved ( Fig. 11-29 ).
What is the pathophysiology of varicose veins?
When legs are dependent for prolonged periods,
- *venous pressures** in these sites can be markedly elevated (up to 10 times normal) and can lead
- *to venous stasis and pedal edema**, even in essentially normal veins (simple orthostatic edema).
Some 10% to 20% of adult males and 25% to 33% of adult females develop lower extremity
varicose veins;
What are the risk factors for varicose veins?
obesity increases risk, and the higher incidence in women is a reflection of the
elevated venous pressure in lower legs caused by pregnancy. A familial tendency toward
premature varicosities has been noted.
FIGURE 11-29 Varicose veins of the leg (arrow).
Varicose dilation renders the venous valves what?
- incompetent and leads to stasis,
- congestion,
- edema,
- pain, and
- thrombosis.
What is the most disabling sequelae of varicose veins?
- include persistent edema in the extremity and
- ischemic skin changes, including stasis dermatitis and ulcerations;
- poor wound healing and superimposed infections can lead to chronic varicose ulcers.
Notably, embolism from these superficial veins is very rare. This is in sharp contrast to the relatively frequent
thromboembolism that arises from thrombosed deep veins (see below and Chapter 4 ).
Can embolism arise from superficial veins?
Notably, embolism
from these superficial veins is very rare.
This is in sharp contrast to the relatively frequent
thromboembolism that arises from thrombosed deep veins (see below and Chapter 4 ).
Varicosities that occur in two other sites deserve special mention
- Esophageal varices.
- Hemorrhoids
Discuss the pathophysiology of Esophageal varices
Liver cirrhosis (less frequently, portal vein obstruction or hepatic vein thrombosis) causes portal vein hypertension ( Chapter 18 )
. Portal hypertension
leads to the opening of porto-systemic shunts that increase the blood flow into veins at
the gastro-esophageal junction (forming esophageal varices), the rectum (forming
hemorrhoids), andperiumbilical veins of the abdominal wall (forming a caput medusa).
Esophageal varices are the most important, since their rupture can lead to massive (even fatal) upper gastrointestinal hemorrhage.
Hemorrhoids result from what?
Hemorrhoids can also result from primary varicose dilation of the venous plexus at the
anorectal junction (e.g., through prolonged pelvic vascular congestion due to pregnancy or chronic constipation).
Hemorrhoids are uncomfortable and may be a source of
bleeding; they can also thrombose and get inflamed, and are prone to painful
ulceration
What is the site of more than 90% of cases site of more than 90% of cases?
Deep leg veins
What are thrombophlebitis and
phlebothrombosis?
the two terms are largely interchangeable designations for venous thrombosis and inflammation.
What are the additional sites for THROMBOPHLEBITIS AND PHLEBOTHROMBOSIS?
- periprostatic venous plexus in males and the
- pelvic venous plexus in females are additional sites,
- as are the large veins in the skull and
- the dural sinuses (especially in the setting of infection or inflammation).
- Peritoneal infections, including peritonitis,
appendicitis, salpingitis, and pelvic abscesses, as well as certain thrombophilic conditions
associated with platelet hyperactivity (e.g., polycythemia vera, Chapter 13 ), can lead to portal
vein thrombosis