1. Lower Extremity Wounds: The role of the vascular technologist
Jesse Thomas, RVT
UNC Health Care

2. Disclosures No relevant conflicts of interest to declare

3. Objectives Review types of wounds Discuss risk factors
Role of Duplex Imaging
Role as a Technologist
This presentation will NOT address the use of ultrasound as a wound management and/or treatment tool.

5. Types of Wounds Arterial Venous Neuropathic Small vessel/Vasculitis
Pressure ulcers

6. Arterial Ischemic wounds Result of inadequate blood supply
Tissue hypoxia and tissue damage
Most commonly result of atherosclerotic disease (PAD)

7. PAD Narrowing of arteries to the limbs that reduces blood flow
More common in LE
Atherosclerosis – build up of fatty deposits (plaque)

8. Arterial Risk Factors High cholesterol Aging HTN Diabetes Smoking
Family hx of cardiovascular disease
Obesity

10. PAD Approximately 8 million people in the US 12-20% in those >60
Public awareness around 25%
Associated with significant morbidity and mortality
Source: National Center for Chronic Disease Prevention and Health Promotion

11. PAD May present with variety of signs/symptoms Claudication – to limp
Aching, cramping pain brought on by exercise and relieved with rest
Calf, thigh, hips or buttocks

12. PAD
Rest pain
Non-healing ulceration
gangrene

13. Arterial Ulcers Characteristics “punched out” appearance
Smooth wound edges
Surrounding skin may exhibit dusky erythema
Cool to touch
Hairless, thin, brittle with shiny texture

14. Arterial Ulcers Typically lower leg Lateral foot Toes
Pressure points or where injury has occurred

15. Arterial Ulcers
Jesse, why do I care what these look like and are you done showing these nasty pictures?

16. Role of Sonographer Patient history Physical exam ABI’s
Clues to what is going on before you put the transducer on the patient

17. Role of Duplex Presence or absence of disease Severity Physiologic
Anatomic
Location
Single level
Asymptomatic
claudication
Multi-level
Claudication
Rest pain
ulcerations

18. Pressures Ankle/Brachial Index (ABI) 1.0-1.2 Normal
may indicate presence of arterial obstruction
< Evidence of arterial obstruction, claudication
<0.40 associated with rest pain or tissue loss

19. Pressures--Toe Photoplethysmography (PPG)
Infrared light which responds to changes in blood content near the surface of the skin
Waveform analysis and pressure measurement

20. Pressures--Toe Disease from the level of the ankle to the toe
Diabetics
Wound healing potential
Absolute number and index

21. Pressures--Toe
A toe/ankle index >0.60 suggests the absence of hemodynamically significant obstruction between the ankle and the toe
A toe/brachial index >0.60 suggests the absence of hemodynamically significant obstruction between the heart and the digit

22. Pressures--Toe

23. TCPo2 Transcutaneous oxygen tension Patient in supine position
Evaluates oxygen delivery to tissue
Indirect measure of local blood flow
Aids in determining wound healing potential
Patient in supine position
Small electrodes placed at chest, below knee, and 2 over dorsum of foot
Electrodes in the sensors heat area underneath the skin to dilate capillaries
Results recorded and measured in mmHg
>30 mmHg – greater success for wound healing
<30 mmHg - suggests high likelihood of wound not healing

26. Pressures--Segmental
Typically 3 or 4 cuff system
High thigh, above knee, calf, ankle
Measures pressure at each level
>30mmHg gradient from level to level is significant
>40mmHg indicates occlusion
>20mmHg from side to side is also significant

27. Pressures--Segmental
Pitfalls include
Medial arterial calcification
Limb girth
Inappropriate cuff size
Can be uncomfortable for patient

28. Pressures--Segmental

29. Pulse Volume Recordings (PVR)
Measures pressure changes in the bladder of the cuff wrapped around the leg
These changes reflect change in cuff volume
Can use same cuffs as used for segmental pressures

30. PVR
A 1mmHg pressure change detected in the cuff produces a 20mm deflection (amplitude) on the chart recorder
Using appropriate size cuffs, a preset pressure is obtained
A recording is then obtained

31. PVR

32. PVR/Segmental Pressures
PVR waveforms and segmental pressures are complimentary tests
If differences exist then a source of error should be investigated

33. Duplex Image based evaluation
Looking for anatomic disease and physiologic disease

34. Duplex – Segmental

35. Duplex

36. PW Doppler--Duplex Velocity Ratio (VR) = 6.1 Velocity Ratio = v2/v1
V2= highest peak systolic velocity
V1= proximal normal vessel
Velocity Ratio (VR) = 6.1

37. Arterial Ulcers
Role of Duplex essential to understanding presence, location, and severity of disease
Guides intervention and management
Indicator wound healing potential

38. Changing Gears

39. Venous Ulcers
Result of sustained venous hypertension (Chronic venous insufficiency)
Incompetent valves or poor calf muscle pump
Local venous dilatation and pooling
Traps leukocytes that may release proteolytic enzymes that destroy tissues
May also “trap” important growth factors within vein rendering them unavailable for wound repair

40. Venous 70%-90% of chronic wound cases
Estimated 2.5 million patients in the US
Rarely fatal - can severely diminish quality of life

41. Venous Ulcers CVI Risk factors > Age Hx DVT Surgery
Restricted mobility
CHF
Cancer
Obesity
Smoking
Family hx VTE
Hypercoable state (Factor V Leiden, Protein C/S deficiency, etc.)
Sedentary lifestyle
Varicosities

42. Venous Ulcers Wound characteristics Gaiter region – medial malleolus
Superficial, irregular shape
Skin shiny and tight (edema)
Brown or purple discoloration – “stasis skin changes”

43. Stasis Skin Changes

44. Varicose Veins

45. Varicose Veins

46. Varicose Veins

47. Varicose Veins Complications
Swelling
Pain/aching
itching
Leg heaviness
Phlebitis – inflammation of vein
Superficial thrombophlebitis
bleeding
Cosmetic
Not commonly associated with venous ulcers when isolated to the superficial system

48. Role of the Sonographer
Patient history
Physical exam
Clues to what is going on before you put the transducer on the patient

49. Role of Duplex Presence or absence of disease Severity Physiologic
Anatomic
Location
Deep
Superficial

50. Venous Obstruction
Presence or absence of deep or superficial venous obstruction
Compression ultrasound

51. Venous Obstruction Thrombus Characteristics Acute Chronic
Softly echogenic
Spongy
Dilated vein
Smooth borders
Chronic
Brightly echogenic
Rigid
Contracted vein
Irregular borders
Presence of collaterals

54. Acute or Chronic?
These distinguishing characteristics are not absolute
“Can be useful in estimating the age of a thrombus and the risk of its embolization.” (Techniques of Venous Imaging. Talbot, Oliver. 1992)

55. Venous Duplex Complete and careful evaluation Deep Superficial CFV Fv
Pop
Tibials
Gastrocs, soleals, etc.
Superficial
Great Saphenous Vein (GSV)
Small Saphenous Vein (SSV)
tributaries

60. Venous Insufficiency Evaluation of reflux (deep and superficial)
Supine
Manual hand augments
Standing
Rapid inflation/deflation cuff system
“stresses” vein – hydrostatic pressure
Valsalva
Patient unable to stand

62. Venous Insufficiency Patient standing Cuff around calf
Rapidly inflates
Measure reflux on cuff deflation
Ergonomic challenges
Patient limitations

66. Venous Insufficiency Normal values Abnormal
< 0.5 seconds
Abnormal
> 0.5 seconds
Indication of valvular incompetency (reflux)

67. Perforator Assessment
Connection between deep and superficial systems
Drains superficial into deep system
Contain valves
Associated with ulcer formation

68. Perforator Assessment
Dodd’s
Boyd’s
Cockett’s
Name given by 1st physician who described them

70. Venous Duplex Other considerations Size of veins “map” of veins
May help determine intervention method
Too large may not respond well to local sclerotherapy or some types of venous ablation
“map” of veins
Anatomical blueprint sometimes required
Help guide intervening physician

71. Venous Ulcers
Role of Duplex essential to understanding presence, location, and severity of disease
Guides intervention and management

72. Conclusion
Patients presenting with ulcerations to the vascular lab is a common occurrence
Technologist and physician education important
Use all available skills and tools to assess your patients
Wound management is complex and your role is critical in providing the necessary vascular information

73. Thank you!