1. Use of Doppler in Wound Care Management’
The Institute of Community Health Nursing
17/05/2017

2. Theory of ABPI
The APBI is the ratio of the systolic B/P measured at the ankle to that measured at the brachial artery (arm)

3. Theory of ABPI What is an Ankle Brachial Pressure Index?
The ankle-brachial pressure index (ABPI) or ankle-brachial index (ABI) is the ratio of the blood pressure at the ankle to the blood pressure in the upper arm (brachium)
Compared to the arm, lower blood pressure in the leg is an indication of blocked arteries due to peripheral artery disease (PAD)

4. Theory of ABPI
Systolic B/P in the legs is equal (or slightly greater than) systolic B/P in the arms (= 1)
Circulatory system is a closed system
When an arterial stenosis (or narrowing) is present, a reduction in pressure(B/P) occurs distally to the lesion. (= 0.9)
This can be detected by ABPI or Doppler

5. Theory of ABPI
ABPI is an objective assessment in identifying arterial disease.
Ratio of the ankle to the brachial systolic pressure
Uses a hand held Doppler ultrasound probe instead of stethoscope to determine the systolic reading.
Divide the ankle systolic pressure(highest) by the (highest)brachial systolic pressure

6. Theory of ABPI
Formula Ankle The highest systolic reading in the ankle Brachial The highest systolic reading in the arm

7. Theory of ABPI
Sounds
Doppler probe makes audible the pressure at which the systolic pulse return
Normal “ triphasic” signal
This represents the three phases of arterial flow
Three distinct sounds heard during a single cardiac cycle (Donnelly et al 2000)

8. Theory of ABPI Phases Blood rushes forward Reverses briefly
Propels forward again
This is echoing the elastic wall of the main artery (Aorta) leaving the heart as it stretches and contracts

9. Theory of ABPI Sounds Triphasic waveform- all three sounds are present
Biphasic- the first two are present
Monophasic- first one is observed

10. Theory of ABPI
Sounds
Important to understand what the three sounds represent as increasing artery stenosis results in progressive dampening of the waveform and the development of monophasic sound.
(Vowden et al 2004)

11. Assessment Assessment
Important to assess the arterial supply to the limbs prior to applying compression therapy
Arterial disease can co-exist in approximately 10-20% with lower limb ulceration (Vowden 2001)
ABPI should be done at the beginning of treatment and every three months(or as indicated) while compression therapy is used.

13. Assessment
ABPI using a Doppler probe is a reliable way of detecting evidence of arterial insufficiency
Also shows if arterial insufficiency is developing
ABPI result itself is NOT a diagnostic indicator of venous disease
Guides the clinicians decision making towards safe levels of treatment

14. Danger!!
Failure to recognise arterial disease or incorrect interpretation of ABPI results can result in the unsafe application of high compression therapy
Pressure damage
Exposed tendons
Tissue damage
Tissue necrosis

15. Taking a reading Ensure that client is lying flat for 15-20-minutes
Semi reclined if patient cannot lie flat due to medical conditions
Take the brachial systolic pressure reading on both arms and record the highest.
Place the cuff on the lower limb protecting the ulcer site
Take the systolic reading using the Dorsalis pedis and posterior tibial artery.
Record the higher of the two
Calculate the reading by dividing the highest ankle systolic by the highest brachial systolic.

16. Pedal Pulses
Palpation of pulses not a fail safe way to determine arterial sufficiency
In one study, lack of pedal pulses had a positive predictive value for significant arterial disease in only 35% of clients.
37% with palpable pedal pulses were found to have significant arterial disease
(Moffatt, O Hare 1995)

17. Pedal Pulses Dorsalis pedis congenitally absent in 12% of population
Oedema can make pedal pulses hard to palpate
Clients with intermittent claudication can have palpable pulses at rest that disappear on walking
Diabetics can have pulses and have significant small vessel disease

18. Pulse Points Arm… Brachial Artery in both arms
Limbs… Dorsalis Pedis, Posterior Tibial pulse

20. ABPI Readings ABPI between 0.92 and 1.30 = normal
Greater than 1.30= calcified artery, false result
Greater than 0.8= May be safe for full compression (comprehensive history and physical examination)
Between 0.5 and 0.8= reduced compression
Mixed ( ABPI < 0.5)- Urgent referral to vascular specialist-NO COMPRESSION

21. Extrinsic and Intrinsic factors
Ambient Temperature
Age
Ethnicity
Height
Pulse volume
Smoking
Medication
White coat syndrome

22. Extrinsic and Intrinsic factors
Take into consideration
Make reasonable adjustments
May have negligible effects on the diagnostic ability of ABPI

23. Cuff size and position Appropriate to limb size
Width should be at least 40% of the limb circumference
Standard and large cuff recommended
Above the ankle and above the elbow
Pulse point accessible
May be easier to have cuff upside down so that the tube is away form the pulse point

24. Equipment Hand held Doppler (or equivalent)
Probe.. 8mgHz for lower limb assessment, 5mhHz if there is a lot of oedema
Cuff
Sphygmomanometer
Ultrasound gel
Tissues
Cling film or equivalent to cover ulcer

25. Contra Indications Recent DVT ( within 2 weeks )
Sickle cell anaemia (refer)
Infection ( should be treated prior to ABPI and application of compression)
Caution with Diabetic due to hardening of arteries

26. Issues to look out for?
Cuff repeatedly inflated or inflated for long periods
Can cause ankle pressure to fall and affect the reading

27. Issues to look out for? Cuff not at the ankle
Ankle systolic pressure not measured, pressure is usually higher than ankle pressure

28. Issues to look out for?
Pulse is irregular or the cuff is deflated too rapidly
True systolic reading may be missed

29. Issues to look out for?
Vessels are calcified, limbs are large, fatty, oedematous, cuff too small or limbs dependant
Inappropriately high readings are obtained

30. Issues to look out for?
Central systolic pressure may influence “normal range” for ABPI
Has the patient got Hypertension?

31. Conclusion
Once the procedure is followed correctly with proper consideration give to technique, risk factors and data interpretation, ABPI is a safe and reliable method of monitoring arterial disease

32. Reference
Worboys F, (2006) How to obtain the resting ABPI in leg ulcer Management : Wound Essentials (Technical Guide)
VowdenP, Vowden K (2001) Doppler Assessment and ABPI; Interpretation in the management of leg ulceration. World Wide Wounds