Module 5: Acute Venous pathophysiology Flashcards
(161 cards)
1
Q
What is a D-Dimer Positive?
A
Blood test that detects a certain protein in the presence of some sort of blood clot.
2
Q
DVT occurs in about how many Canadians each year?
A
200,000
3
Q
Pulmonary embolism is the leading cause of what death associated with which demographic of patients?
A
Maternal women with child birth
4
Q
A women’s risk of developing Venous thromboembolism (VTE) is how much greater if pregnant?
A
Six times
5
Q
Pulmonary embolism causes more deaths annually in North America than what? 3
A
- Breast cancer
- AIDs
- Highway fatalities
6
Q
Fetal Pulmonary embolism may be the most common preventative cause of ________ in ____________?
A
Hospital death in North America
7
Q
Approximately how many patients are hospitalized each year for DVT in Canada each year?
A
60,000
8
Q
What is the most common reason we scan extremity veins?
A
DVT
9
Q
How much DVT is clinically diagnosed diagnose?
A
50%
10
Q
What are some complications of DVT? 2
A
- Pulmonary embolism
- Chronic venous insufficiency (CVI)
11
Q
How much pulmonary embolism originate in LE?
A
80%
12
Q
If untreated what is the mortality rate of pulmonary embolism?
A
30%
13
Q
Venous diseases can be what two things?
A
acute or chronic
14
Q
Venous disease can effect what systems?
A
Both deep or superficial systems
15
Q
The venous system can also be effected by what?
A
Non- venous pathologies
16
Q
What are some underlying risk factors DVTs? 2
A
- Genetics
- Acquired - more common
17
Q
What are some genetic factors for DVTs? 4
A
- Gender
- Race
- Antithrombin deficiency
- Fact V Leiden mutation
18
Q
Acquired factors can be categorized into what system?
A
Virchow’s Triad
19
Q
What is Virchow’s Triad?
A
- Stasis
- Injury
- Hypercoagulability
20
Q
What is the most common factor for LE DVT?
A
Venous stasis
21
Q
What are some reasons for Venous stasis? 5
A
- Immobility
- Congestive heart failure
- Obesity
- Pregnancy (vein compression L>R)
- Surgery (leg or hip example)
22
Q
How would we get DVT from injuries?
A
Trauma to vessels, Like infection or HTN
23
Q
What is the most common factor for UE DVT?
A
Central lines like peripherally inserted central catheter (PICC)
24
Q
What is hypercoagulability?
A
The clotting ability of blood is increased
25
What are some reasons for Hypercoagulability? 4
1. Pregnancy
2. Cancer
3. Estrogen intake (BCP, HRT)
4. Genetic blood factors
26
What are some questions we ask for patient history for DVT? 5
1. Previous DVT or family history
2. Trauma?
3. Surgery?
4. Bed rest > 4 days
5. Medications (BCP/HRT)
27
What is the difference between signs and symptoms?
**Symptoms are patient recorded and signs are things we can see**
Symptom could be something like pain, we can't see pain
28
What are some common acute signs of onset for DVT? 5
1. Pain
2. **Swelling (edema)**
3. Redness/ erythema
4. Skin warm/ hot to touch
5. Persistent pain (positive Homans sign)
29
What are some Symptoms of Pulmonary embolism? 4
1. SOB
2. Chest pain
3. Hemoptysis
4. Increased heart rate/ respiratory rate
*C his*
30
What are less common signs and symptoms for DVT? 6
1. Ulceration (gaiter area, medical malleoulus) , shallow and round
2. Discoloration in the gaiter area
3. Varicose veins
4. Pallor (phegmasia alba dolens) or getting white
5. Cyanosis (phlegmasia cerulea dolens) or getting blue
6. Positive D-timer test result
*C pup VD*
31
D-dimer test looks for what?
The presence of breakdown products of linked fibrin
32
D-dimers are very how sensitive to clots, and is it specific to DVTs?
Very sensitive 95%, but not specific to DVTs
33
For DVTs false positives occur due to what? 6
1. Trauma
2. Surgeries
3. Pregnancy
4. Malignancy
5. Liver disease
6. Kidney disease
*PMS TLK*
34
If there is a negative D-dimer test how likely is a DVT?
Unlikely
35
What is Well's score?
Clinical assessment that estimates the DVT probabilities
36
What is the reported scores for Well's score?
Low - 0
Intermediate - 1 or 2
High - 3
37
How is the Well's score used for PE? 2
1. Clinical assessment
2. Positive criterion is a given number value
38
What is the PE well's scoring system?
Low probability (<2)
Intermediate (2 to 6)
High (>6)
39
For thrombus formation where does it usually begin?
Soleal calf veins or the valve cusps due to stasis
40
What is thrombus formation?
1. Red blood cells aggregate and cause fibrin formation and adheres to vessels walls
*this induces further thrombosis which propagates along the vessel lumen*
41
Acute stage of thrombus formation is within what time frame?
First 14 days after thrombus forms
42
What are other sites for thrombus? 5
1. Muscular veins (gastrocnemius or soleal sinus)
2. Valves sites
3. Venous confluence
4. Perforators
5. Deep venous system or superficial system
*Vm Vpd*
43
What is the most common site for Calf vein DVT?
Soleal sinus
44
What is the current approaches to treatment for DVT? 2
1. Surveillance with duplex US to check for propagation to larger veins
2. Therapeutic anticoagulation for 6 weeks
45
Between a fem pop DVT and a calf DVT which is more serious? why?
Fem- pop DVT because of the higher risk of PE
46
For fem-pop DVTs what initial test is performed?
Duplex sonography initial test
47
What is the most common treatment for Fem-Pop DVT?
Anticoagulation therapy
48
Imaging the Iliac veins can be challenging and success is dependent on what?
Patients body habitus
49
For Iliac DVTs doppler signals can give what? ( Information given)
Indirect information
50
For iliac DVT we should compare what things and assess what?
We should compare bilateral CFV waveforms and assess the IVC
51
How do we confirm Iliac DVT?
Venography
52
What are UE DVTs a result of?
Central venous catheters
53
Besides Central venous catheters, what can UE DVT be a result of? 3
1. Mediastinal lymphoma
2. Previous radiation therapy
3. Trauma or surgery to the area
54
When can an acute DVT be first seen?
First 14 days
55
Acute thrombus can look how?
**Anechoic to hypoechoic and enlarges the vessel slightly**
There will be incomplete compression of the lumen with the transducer
56
For a sub-acute DVT when would it present and what would it look like?
1 to 2 months old and can be slightly more echogenic and retracts in size
57
When the DVT is distal to where you scan the waveform can show what?
Reduced or absent augment
58
Collateralization is another sign of what?
DVT
59
Collaterals are what?
Accessory vessels that reroute flow around an obstruction.
60
Collaterals may occur rapidly in the presence of what?
DVT and may be readily seen
61
What are some Rare DVT conditions? 4
1. May-Thurber syndrome
2. Pages- Schreotter syndrome
3. Phlegmasia Alba Dolens
4. Phlegmasia cerulean dolens
62
What a some rare conditions of DVT?
1. May- Thurner syndrome
2. Page- Schroetter Syndrome
3. Phlegmasia Alba Dolens
4. Phlegmasia Cerulean Dolens
63
What is another name for May- Thurber Sydrome?
Iliac vein compression syndrome
64
What is May-Thurner syndrome?
Result of an anatomical variant of an overriding RT CIA compressing the LT CIV against the 5th Lumbar vertebra
65
Who is the most common demographic for May-Thurber syndrome?
Young females in their 20s to 40s
66
How does May-Thurner syndrome present like?
Left leg pain and swelling
67
What is the most common demographic for May-Thurner Syndrome?
Young females in their 20s and 40s
68
How do we diagnose May- Thurner Syndrome?
Venography with pressure measurements is the gold standard for diagnosis
69
What may we see during May-Thurner syndrome at the vein site in terms of flow pattern?
May see a narrowing with a jet at the site of the stenosis or a continuous flow pattern distal
70
What is another name for Paget- Schroetter Syndrome?
Spontaneous effort Thrombosis
71
Where is Paget-Schroetter syndrome most commonly seen?
Axillio- Subclavian thrombosis in ambulatory cancer free population
72
What demographic does Paget- Schroetter syndrome commonly affect?
Men, typically in their dominant arm
73
What can Paget-Schroetter syndrome be associated with?
Thoracic inlet abnormalities (cervical rib, muscle)
74
What is another name for Phlegmasia Alba Dolens?
Painful white inflammation
75
What is Phlegmasia alba dolens?
Massive occupation of the major deep venous system
76
Can the blood still drain with Phlegmasia Alba Dolens?
Yes through the collaterals
77
Can blood still drain in Phlegmasia Alba Dolen?
Yes through the Collaterals
78
What does Phlegmasia Alba Dolens look like?
Extensive edema with a white discolouration
79
What does Phlegmasia Alba Dolen progress to?
Cerulea Dolens
80
What is another name for Phlegmasia Cerulea Dolens?
Painful blue inflammation
81
What is Phlegmasia Cerulea Dolens?
Occlusion of the major deep venous system
82
What is Phlegmasia Cerulea Doleans?
Occlusion of the major deep venous system and the collaterals
83
What does Phlegmasia Cerulea Dolens result in?
Reduced arterial flow
84
What does Phlegmasia Cerulea Dolens present with?
Massive thigh and calf swelling with a blue discolouration.
85
In Phlegmasia Cerulea Dolens what happens if we leave it untreated?
Venous gangrene and massive tissue death
86
Would Phlegmasia Cerulea Dolens be an emergency?
It would we a surgical emergency
87
Would Phlegmasia Cerulea Dolens be a emergency?
A surgical emergency
88
Treatments for DVTs can be grouped into how many categories?
Three
89
What are the three categories for DVT treatment?
1. Prevention (control of the risk factors)
2. Medical
3. Surgical
90
How can we prevent a DVT? 4
1. Control the risk factors
2. Limit long period of inactivity
3. Wear support hose *elevating legs*
4. Blood tests to test for hypercoagulability states and blood factors *remember Virchow’s triad*
91
What are some medical treatments for DVT? 2
1. Anticoagulation therapy
2. Thrombolytic agent
92
How long will someone be on anticoagulation therapy for medical treatment?
3-6 months
93
If a clot is recurrent how long will the a person be on anticoagulation therapy?
Life
94
What does Anticoagulation therapy do?
Prevent clot propagation
95
Does anticoagulation therapy dissolve the thrombus?
Nope
96
What happens during the thrombolytic treatment for DVT?
Streptokinase may be injected to dissolve the thrombus
97
When is thrombolytic agents used for DVT?
Used when the symptoms are severe
98
What can Thrombolytic Agents lead to?
Major bleeding episodes
99
What are some surgical treatments for DVTs? 3
1. Venous thrombectomy
2. Bypass grafting
3. Balloon Venoplasty and stunting
100
When do we do a venous thrombectomy?
Patient with impending limb loss (Phlegmasia Cerulea dolens) if a thrombolytic agent does not work.
101
What is bypass grafting?
Caval Occulsion
102
When would we use balloon venoplasty and stenting? 2
1. Chronic iliofemoral DVT
2. May-Thurner Syndrome
103
What is an IVC filter?
An option for patient who cannot be anticoaguated
104
What is superficial thrombophlebitis?
As a painful superficial cord and inflammation in the veins
105
For a superficial thrombophlebitis what can ultrasound do?
Determine the extent of thrombus
106
Approximately how much of the superficial thrombosis has a concurrent DVT or PE?
25%
107
Anticoaguation therapy is indicated if the thrombus is at what level?
5cm more in length or is 3 cm of the SFJ.
*the same consideration is given to the SSV and popliteal anastomosis*
108
What is the treatment for thrombophlebitis? 4
1. Apply heat to site
2. Compression stockings
3. Non- steroidal anti-inflammatory meds
4. Low molecular weight heparin for 45 days
109
What are some corrective tests for venous thromboembolic disease (VTE)? 4
1. Venography
2. CT
3. Nuclear medicine
4. MRI
110
A Venography is what?
A X-ray taken of the leg where contrast media is injected to outline the veins
111
For Venography the contrast is injected where?
Into a large vein in the foot/ankle
112
Venography is a very invasive test and has been largely replaced by what?
Ultrasound
113
Some patients are contraindicated for what procedures?
Venography contrast
114
What is CTs used for in terms of DVTs?
Pulmonary angiogram or CTPA
115
CT is the standard test for what?
Pulmonary embolism
116
CTs also require what to be injected?
Contrast to be injected into the patient
117
What kind of nuclear medicine test used for DVTs?
Ventilation perfusion (V/Q) scan
118
What is the process of the Ventilation-perfusion (V/Q) scan?
Ventilation part involves inhaling a radioactive gas to demonstrate the presence of a Pulmonary embolism
119
What does a V/Q scan show?
Parts of the lung that are getting oxygen
120
What should the perfusion look like for a V/Q scan?
We should look at blood flow to the lung to see if there is diminished flow from clots
121
What is the probability of V/Q scans reporting P/E?
High/ moderate/ low probability
122
What is a isotope Venography?
A nuclear medicine test where a radioisotope is injected to evaluate peripheral and pulmonary veins
123
What does the Isotope Venography tag?
The thrombus
124
How often is isotope Venography used?
Infrequently
125
With such vague symptoms, there are many differentials to consider when you scan, name a couple. 9
1. Bakers cysts
2. Hematoma
3. Edema
4. Lymphedema
5. Infection
6. Abscess
7. Cellulitis
8. Tumours
9. Popliteal A aneurysm
126
What is a bakers cyst?
Dilation of bursa in the Posteromedial knee
127
What is bakers cysts common with?
Degenerative joint disease and rheumatoid arthritis
128
The Baker cysts can extend into what?
Muscle planes, and become hemorrhagic or rupture
129
Baker cysts can cause what? 3 (s/s)
1. Pain
2. Tenderness
3. Swelling
130
How might a bakers cyst look?
Tear drop shape and may not be visible with the knee extending
131
If we see a bakers cysts what should we do?
Measure in three planes and interrogate with colour doppler
132
What causes hematomas?
Results of trauma, anticoaguation therapy or vigorous exercise
133
What is the sonographic appearance dependent of for hematomas?
Dependent on age of occurrence
134
Where should we scan for hematomas?
Where it hurts or where there is a palpable lump
135
If we see a hematoma how should we note it for the rad?
Measure in three planes and interrogate with colour doppler
136
What causes soft tissue edema occur?
Increased venous pressures
137
What are some examples of things that may cause soft tissue edema? 5
1. Heart failure
2. Fluid overload
3. DVT
4. Venous obstruction
5. Presents as leg swelling
138
What is this?
Soft tissue edema
139
If CHF is the cause then the edema is what will we see in terms of edema? Why?
1. Bilateral edema
2. Increased hydrostatic pressure
140
For edemas the patient can present with what? 2
1. Dyspnea
2. Possible negative D-dimer
141
If we see an edema what can we do?
Use ultrasound to rule out DVT
142
What does the waveform of edemas look?
Can be pulsatile
143
What is a lymphedema? What is it due to? 4
obstruction of lymph drainage due to
1. Malignancy
2. Trauma
3. Surgery
144
Where are lymphedemas common?
In the calf and upper extremity
145
2/3 of lymphedema cases are what? (unilateral or bilateral)
Unilateral
146
What does lymphedema’s demonstrate?
Pitting edema
147
What is the appearance of lymphedema’s?
Milky appearance
148
What does an infection- abscess and cellulitis a result of?
Bacterial infection
149
What is a abscess?
Enclosed collection of pus
150
What is cellulitis?
Diffuse collection of fluid within the subcutaneous tissue
151
What may infections cause? 4 (s/s)
1. Swelling
2. Erythema
3. Pain
4. Tenderness
152
Ultrasound infections to do what?
Confirm that the venous system is patent
153
What is adenopathy?
Enlarged lymph nodes that can be mistaken for thrombosed veins
154
Adenopathy may cause what to the legs? 2
1. Limb swelling
2. Compression of veins
155
What does a benign lymph node look like?
1. Ovoid
2. Wider then tall
3. Hypoechoic hilum
4. Less than 1 cm
156
What does a malignant lymph node look like? 4
1. Rounded shape
2. Taller than wide
3. Increased Colour flow
4. Lose normal architecture
157
What are some examples of tumours? 2
1. Benign (Lipoma)
2. Malignant (Sarcoma, Lymphoma)
158
Tumours are usually solid but may have areas of what?
Necrosis
159
As a sonographer what should we do if we see a tumour?
Interrogate with colour and Doppler
160
What does popliteal aneurysm present with? 4
1. Lump or pain behind the knee
2. Dilated arterial wall
3. Colour flow if patent
4. Higher risk with AAA
161
What is this an example of?
Popliteal Aneurysm
