Chapter 11- Veins and Lymphatics

Question 1

What together account for at least 90% of
clinical venous disease?

Answer 1

• Varicose veins and
• phlebothrombosis/thrombophlebitis

Question 2

What are Varicose veins?

Answer 2

abnormally dilated, tortuous veins produced by prolonged, increased intraluminal pressure and loss of vessel wall support.

Question 3

What veins are typically involved in varicose veins?

Answer 3

The superficial veins of the upper and
lower leg are typically involved ( Fig. 11-29 ).

Question 4

What is the pathophysiology of varicose veins?

Answer 4

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;

Question 5

What are the risk factors for varicose veins?

Answer 5

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.

Question 6

Answer 6

FIGURE 11-29 Varicose veins of the leg (arrow).

Question 7

Varicose dilation renders the venous valves what?

Answer 7

• incompetent and leads to stasis,
• congestion,
• edema,
• pain, and
• thrombosis.

Question 8

What is the most disabling sequelae of varicose veins?

Answer 8

• 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 ).

Question 9

Can embolism arise from superficial veins?

Answer 9

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 ).

Question 10

Varicosities that occur in two other sites deserve special mention

Answer 10

• Esophageal varices.
• Hemorrhoids

Question 11

Discuss the pathophysiology of Esophageal varices

Answer 11

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.

Question 12

Hemorrhoids result from what?

Answer 12

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

Question 13

What is the site of more than 90% of cases site of more than 90% of cases?

Answer 13

Deep leg veins

Question 14

What are thrombophlebitis and
phlebothrombosis?

Answer 14

the two terms are largely interchangeable designations for venous thrombosis and inflammation.

Question 15

What are the additional sites for THROMBOPHLEBITIS AND PHLEBOTHROMBOSIS?

Answer 15

• 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

Question 16

For deep venous thrombosis (DVT) of the legs, what is the most important predisposing condition?

Answer 16

prolonged immobilization resulting in decreased blood flow through the veins

This can occur with extended bed rest or from just sitting during extended travel in an
airplane or automobile; thepostoperative state is another independent risk factor in DVT
formation.

Clearly, other mechanical factors that slow venous return also promote the
development of DVT; these include congestive heart failure, pregnancy, and obesity

Question 17

What are the risk factors for DVT?

Answer 17

• extended bed rest or from just sitting during extended travel in an airplane or automobile;
• the postoperative state is another independent risk factor in DVT formation.
• Clearly, other mechanical factors that slow venous return also promote the development of DVT; these include congestive heart failure, pregnancy, and obesity

Question 18

What is an independent risk factor for DVT formation?

Answer 18

the postoperative state is another independent risk factor in DVT formation

Question 19

What often predisposes to thrombophlebitis?

Answer 19

Systemic hypercoagulability ( Chapter 4 )

In patients with
cancer, particularly adenocarcinomas, hypercoagulability occurs as a paraneoplastic syndrome related to elaboration of pro-coagulant factors by the tumor cells ( Chapter 7 ).

In this setting,
venous thromboses classically appear in one site, disappear, and then reoccur in other veins;
this is referred to as migratory thrombophlebitis (Trousseau sign) .

Question 20

What is Trousseau sign?

Answer 20

In this setting,
venous thromboses classically appear in one site, disappear, and then reoccur in other veins;
this is referred to as migratory thrombophlebitis (Trousseau sign) .

Question 21

Thrombi in the legs tend to produce few, if any, reliable signs or symptoms.

True or False

Answer 21

True

Thrombi in the legs tend to produce few, if any, reliable signs or symptoms.

Indeed, local
manifestations, including distal edema, cyanosis, superficial vein dilation, heat, tenderness,
redness, swelling, and pain may be entirely absent,especially inbedridden patients.

In some
cases pain can be elicited by pressure over affected veins, squeezing the calf muscles, or
forced dorsiflexion of the foot (Homan sign); absence of these findings does not exclude a
diagnosis of DVT .

Question 22

What is Homan sign?

Answer 22

In some

• *cases pain can be elicited by pressure over affected** veins, squeezing the calf muscles, or
• *forced dorsiflexion of the foot (Homan sign);**

absence of these findings does not exclude a
diagnosis of DVT .

Question 23

What is a serious complication of DVT?

Answer 23

• *Pulmonary embolism** resulting from
• *fragmentation or detachment of the whole venous thrombus**.

In many cases the first
manifestation of thrombophlebitis is a pulmonary embolus. Depending on the size and number
of emboli, the outcome can range from no symptoms to death

Question 24

What is the first manifestation of thrombophlebitis in many cases?

Answer 24

pulmonary embolus.

Depending on the size and number
of emboli, the outcome can range from no symptoms to death

Question 25

What is superior vena caval syndrome?

Answer 25

The superior vena caval syndrome is usually caused by **neoplasms that compress or invade the superior vena cava**, such as**bronchogenic carcinoma or mediastinal lymphoma.** The resulting obstruction produces a characteristic clinical complex that includes **marked dilation of the veins of the head, neck, and arms and cyanosis.** Pulmonary vessels can also be compressed, **causing respiratory distress**

Question 26

What is the inferior vena caval syndrome?

Answer 26

The inferior vena caval syndrome can be caused by **neoplasms that compress or invade the inferior vena cava (IVC)**or by a**thrombus from the hepatic, renal, or lower extremity veins that propagates upward.** Certain neoplasms—particularly hepatocellular carcinoma and renal cell carcinoma—show a striking tendency to grow within veins, and these may ultimately occlude the IVC.

Question 27

What are the certain neoplasm that show a striking tendency to grow within the veins and the may ultimately occlude the IVC?

Answer 27

Certain neoplasms—particularly hepatocellular carcinoma and renal cell carcinoma I

Question 28

VC obstruction induceswhat symptoms?

Answer 28

* **marked lower extremity edema,** * **distention of the superficial** collateral veins of the lower abdomen, * and—with renal vein involvement—**massive proteinuria.**

Question 29

Which is more common primary or secondary disorders of lymphatic vessels?

Answer 29

**Primary disorders of lymphatic vessels are extremely uncommon**; secondary processes are **much more frequent and develop in association with inflammation or malignancies.**

Question 30

What is Lymphangitis?

Answer 30

**acute inflammation** elicited when **bacterial infections spread into lymphatics**;

Question 31

WHat are the most common agents that cause lymphagitis

Answer 31

group A β-hemolytic streptococci**, although any microbe may be associated**.

Question 32

What is the apperance of the affeceted lymphatics in lymphangitis?

Answer 32

The affected lymphatics are **dilated and filled with an exudate of neutrophils** and **monocytes;** these **infiltrates can extend through the vessel wall into the perilymphatic tissues and, in severe cases, produce cellulitis or focal abscesses.** Clinically, **lymphangitis is recognized by red, painful subcutaneous streaks**(the inflamed lymphatics), and**painful enlargement of draining lymph nodes** (acute lymphadenitis). If bacteria are not successfully contained within the lymph nodes, subsequent passage into the venous circulation can result in bacteremia or sepsis.

Question 33

Primary lymphedema can occur due to what?

Answer 33

* an **isolated congenital defect** (simple congenital lymphedema) * or as the **familial Milroy disease** (heredofamilial congenital lymphedema) , which causes lymphatic agenesis or hypoplasia.

Question 34

Secondary or obstructive lymphedema stems from blockage of a previously normal lymphatic; such obstruction can result from

Answer 34

* Malignant tumors obstructing either the lymphatic channels or the regional lymph nodes * • Surgical procedures that remove regional groups of lymph nodes (e.g., axillary lymph nodes in radical mastectomy) * • Post-irradiation fibrosis * • Filariasis * • Post-inflammatory thrombosis and scarring

Question 35

What are the outcomes of lymphadema?

Answer 35

Regardless of the cause, **lymphedema increases the hydrostatic pressure in the lymphatics distal to the obstruction and causes increased interstitial fluid accumulation.** Persistence of this edema leads to i**ncreased deposition of interstitial connective tissue, brawny induration or peau d'orange (orange peel)**appearance of the overlying skin, and**eventually ulcers due to inadequate tissue perfusion**. Milky accumulations of lymph in various spaces are designated **chylous ascites (abdomen), chylothorax, and chylopericardium;** these are caused by rupture of dilated lymphatics, typically obstructed secondary to an infiltrating tumor mass.