Peripheral Arterial Disease Education and ABI Training for Vascular Nurses

Presented by The Society for Vascular Nursing Comprehensive In-Service Lecture Kit Supported by an educational grant from Bristol-Myers Squibb/Sanofi Partnership

PERIPHERAL ARTERIAL DISEASE Education and ABI Training for Vascular Nurses

A Train the Trainer Program

The Ankle Brachial Index: The Key to Early Detection and Management of Peripheral Arterial Disease

Acknowledgements

 

Course Development

– ABI Registry Task Force

Diane Treat-Jacobson, Ph.D., R.N.

Carolyn Robinson MSN, RN, CNP,CVN Marge Lovell RN, CCRC, CVN, BEd Patricia Lewis, MS, FNP, CVN M. Kate Schmidt, BSN, RN, CVN Contact Information Society for Vascular Nursing 203 Washington St., PMB 311 Salem, MA 01970 888-536-4786; 978-744-5005; Fax: 978-744-5029

Peripheral Arterial Disease and Claudication

 Peripheral Arterial Disease (PAD) A disorder caused by atherosclerosis that limits blood flow to the limbs  Claudication A symptom of PAD characterized by pain, aching, or fatigue in working skeletal muscles. Claudication arises when there is insufficient blood flow to meet the metabolic demands in leg muscles of ambulating patients

New PAD Guidelines

     Enhanced quality of patient care Increased recognition of the importance of atherosclerotic lower extremity PAD: – – Prevalence Cardiovascular risk – Quality of life Improved ability to detect and treat renal artery disease Improved ability to detect and treat AAA The evidence base has become increasingly robust, so that a data-driven care guideline is now possible

Defining a Population “At Risk” for Lower Extremity PAD

      Age less than 50 years with diabetes, and one additional risk factor (e.g., smoking, dyslipidemia, hypertension, or hyperhomocysteinemia) Age 50 to 69 years and history of smoking or diabetes Age 70 years and older Leg symptoms with exertion (suggestive of claudication) or ischemic rest pain Abnormal lower extremity pulse examination Known atherosclerotic coronary, carotid, or renal artery disease

Relative Prevalence of Peripheral Arterial Disease

Age (years) 40-59 60-69



70 Population (millions) 68.9

19.8

24.8

113.5

PAD (millions) 2.1

1.6

4.7

8.4

Criqui MH et al. N Engl J Med.

1992;326:381-6.

Hiatt W et al. Circulation. 1995;91:1472-9.

Porter J. Mod Med. 1987;55:66-75.

US Census Data, 1998 estimates.

Web address www.census.gov/population/estimates/nation/infile2-1.txt

Claudication (millions) 0.9

0.8

2.5

4.2

Systemic Manifestations of Atherosclerosis

• • • • • •

TIA Ischemic stroke

• •

Myocardial Infarction Unstable angina pectoris

•

Renovascular hypertension

•

Erectile dysfunction

•

Claudication

•

Critical limb ischemia, rest pain, gangrene, amputation

Prevalence of PAD

NHANES 1 Aged >40 years San Diego 2 Mean age 66 years NHANES 1 Aged 70 years Rotterdam 3 Aged >55 years

4.3% 11.7% 14.5% 19.1%

Diehm 4 Aged 65 years PARTNERS 5 Aged >70 years, or 50–69 years with a history diabetes or smoking

19.8%

0%

In a primary care population defined by age and common risk factors, the prevalence of PAD was approximately one in three patients 29%

5% 10% 15% 20% 25% 30%

NHANES=National Health and Nutrition Examination Study; PARTNERS=PAD Awareness, Risk, and Treatment: New Resources for Survival [program].

1. Selvin E, Erlinger TP.

Circulation

. 2004;110:738-743.

2. Criqui MH et al.

Circulation

. 1985;71:510-515.

3. Diehm C et al.

Atherosclerosis

. 2004;172:95-105. 4. Meijer WT et al.

Arterioscler Thromb Vasc Biol

. 1998;18:185-192. 5. Hirsch AT et al.

JAMA

. 2001;286:1317-1324.

35%

Prevalence of PAD Increases with Age Rotterdam Study (ABI <0.9) 1 60 50 San Diego Study (PAD by noninvasive tests) 2 40 30 20 10 0 55-59 60-64 65-69 70-74 Age Group, years 75-79

1. Meijer WT, et al.

Arterioscler Thromb Vasc Biol

. 1998;18:185-192. 2. Criqui MH, et al.

Circulation

. 1985;71:510-515.

80-84 85-89

ABI=ankle-brachial index

Gender Differences in the Prevalence of PAD

2 0 6 4 18 16 14 12 10 8 6880 Consecutive Patients (61% Female) in 344 Primary Care Offices Women Men <70

Diehm C.

Atherosclerosis

. 2004;172:95-105.

70–74 75–79 Age (years) 80–74 >85

Diabetes Increases Risk of PAD

25 20 15 10 5 12.5

19.9* 22.4* 0 Normal glucose tolerance Impaired glucose tolerance Diabetes

Impaired Glucose Tolerance was defined as oral glucose tolerance test value ≥140 mg/dL but <200 mg/dL.

*P

 .05 vs normal glucose tolerance. Reprinted with permission from Lee AJ et al.

Br J Haematol.

1999;105:648-654. www.blackwell-synergy.com

Ethnicity and PAD: The San Diego Population Study

10 9 5 4 3 2 1 8 7 6 0 NHW Black Hispanic Asian

NHW = Non-hispanic white Criqui et al.

Circulation.

2005: 112: 2703-2707.

Risk Factors for PAD

Reduced Increased

Smoking Diabetes Hypertension Hypercholesterolemia Hyperhomocysteinemia C-Reactive Protein Relative Risk 0 1 2 3 4 5 6 Hirsch AT, et al.

J Am Coll Cardiol.

2006;47:e1-e192.

Pathogenesis of Progressive Atherosclerosis

Risk of Ischemic Events

   Previous MI – 5-7 times more likely to have another MI – 3-4 times more likely to have a stroke Previous stroke – 9 times more likely to have another stroke – 2-3 times more likely to have an MI PAD – 4 times more likely to have an MI – 2-3 times more likely to have stroke

Long-term Survival in Patients With PAD

100 75 50 25 Normal subjects Asymptomatic PAD Symptomatic PAD Severe symptomatic PAD 0 2 4 6

Year

8 10 12

Criqui MH et al.

N Engl J Med.

1992;326:381 386. Copyright © 1992 Massachusetts Medical Society. All rights reserved.

Contemporary PAD

Rates of Myocardial Infarction and Death

3649 subjects (average age 64 yrs) followed up for 7.2 years % 50 40 30 20 10 0 No PAD MI Asymptomatic PAD Death Symptomatic PAD

Hooi JD, et al.

J Clin Epid.

2004;57:294 –300.

Association Between ABI and All-Cause Mortality* Risk increases at ABI values below 1.0 and above 1.3

N=5748 30 20 10 0 80 70 60 50 40 <0.61

(n=156) 0.61-0.70

(n=141) 0.71-0.80

(n=186) 0.81-0.90

(n=310) 0.91-1.00

(n=709) 1.01-1.10

(n=1750) 1.11-1.20

(n=1578) 1.21-1.30

(n= 696) 1.31-1.40

(n=156)

Baseline ABI Age range=mid- to late-50s; *Median duration of follow-up was 11.1 (0.1

–12) years.

Adapted from O’Hare AM et al.

Circulation

. 2006;113:388-393.

>1.40

(n=66)

A Risk Factor “Report Card” for all Individuals with Atherosclerosis

Tobacco smoking  Complete, immediate cessation Hypertension  BP less than 130/85 mmHg  Diabetes Hb A 1 C <7.0

Dyslipidemia    LDL Cholesterol less than 100 mg/dl Raise HDL-c Lower Triglycerides Inactivity  Follow activity guidelines

Antiplatelet therapy (like aspirin or Plavix) is: Mandatory

PAD

Pathway of Disability in Intermittent Claudication

Reduced muscle strength Poor walking ability and IC Disability Denervation, muscle-fiber atrophy, decreased type II fibers, decreased oxidative metabolism Cycle of deconditioning: decreased HDL, poorer glycemic control, poorer BP control Adapted from McDermott M. Am J Med . 1999;CE (I):18-24.

Impact of PAD on Quality of Life

       PAD Diagnosis and Management Symptom Experience Limitation in Physical Functioning Limitation in Social Functioning Compromise of Self Uncertainty Adaptation

SF-36 Scores in Health and Disease

No. of people

Intermittent claudication CHF Chronic lung disease Average adult Average well adult

30 34 36 38 40 50 Physical Component Summary Score 55

Location of Obstruction Influences Symptoms

Obstruction in: Aorta or iliac artery Femoral artery or branches Claudication in: Buttock, hip, thigh Thigh, calf Popliteal artery Calf, ankle, foot

Claudication: A Symptom of Peripheral Arterial Disease

     Exertional aching pain, cramping, tightness, fatigue Occurs in muscle groups, not joints (buttocks, hips, legs, calves) Reproducible from one day to the next on similar terrain Resolves completely with rest Occurs again at the same distance once activity has been resumed

Symptoms in PAD

Patients with PAD Symptomatic PAD ~39% 1 Asymptomatic PAD ~61% 1 Typical Symptoms (Intermittent Claudication) ~9% Atypical Symptoms ~91%

1.

2.

American Heart Association. Heart Disease and Stroke Statistics —2005 Update. 2005.

Hirsch AT, et al. JAMA. 2001;286:1317-1324.

Clinical Assessment of Peripheral Arterial Disease

Components of Clinical Assessment

  

Complete history

– Risk factor assessment – Activity assessment

Review of medications Physical examination

– Inspection of lower extremities – Pulse exam

Questions for Patients

 Do you develop discomfort in your legs when you walk? – Cramping, aching, fatigue  Do you get this pain when you are sitting standing, or lying?

 Do symptoms only start when you walk?  Does the discomfort always occur at about the same distance?  Do symptoms resolve once you stop walking?

PAD Pulse Evaluation

Right Left Femoral Popliteal Dorsalis pedis Posterior tibial Ankle–brachial index Note: 0-4 scale, where 0 = absent, 2 = Diminished, 4 = Normal Limits

The Ankle-Brachial Index (ABI)

    The first diagnostic assessment that should be done to evaluate a patient for PAD after a pulse exam in the presence of risk factors or if claudication is suspected. Inexpensive, accurate and can be done in the primary care setting The ABI is 95% sensitive and 99% specific for PAD Predicts limb survival, potential for wound healing, and mortality

The Ankle-Brachial Index (ABI)



Indicated

– In the absence of palpable pulses, or if pulses are diminished – In the presence or suspicion of claudication, foot pain at rest, or a non-healing foot ulcer – Age greater than 70 years of age, >50 years with risk factors (diabetes, smoking)

Concept of ABI

The systolic blood pressure in the leg should be approximately the same as the systolic blood pressure in the arm.

Therefore, the ratio of systolic blood pressure in the leg vs the arm should be approximately 1 or slightly higher.

Leg pressure ÷ ABI has been found to be 95% sensitive and 99% specific for angiographically diagnosed PAD.

≈ 1 Arm pressure

Adapted from Weitz JI, et al.

Circulation.

1996;94:3026-3049.

Understanding the ABI

    Performed with patient resting in supine position All pressures are measured with a arterial Doppler and appropriately sized blood pressure cuff Both brachial pressures are measured Ankle pressures are measured using the posterior tibial and/or dorsalis pedis arteries

Measuring the Ankle-Brachial Index (ABI) Step 1: Gather Equipment Needed Equipment needed: 1. Blood Pressure Cuff 2. Hand-held 5-10 MHz Doppler probe 3. Ultrasound Gel

American Diabetes Association.

Diabetes Care

2003: 26; 3333 –3341.

Measuring the Ankle-Brachial Index (ABI) Step 2: Position the Patient Place patient in supine position for 5 – 10 minutes minutes

American Diabetes Association.

Diabetes Care

2003: 26; 3333 –3341.

Measuring the Ankle-Brachial Index (ABI) Step 3: Measure the Brachial Blood Pressure 1.

Place the blood pressure cuff on the arm above the elbow. 2. Apply gel to the skin surface.

3. Place the Doppler probe over the brachial pulse 4. Inflate the cuff to approx. 20 mm/hg above the point where systolic sounds are no longer heard. 5. Deflate the cuff slowly until the arterial signal returns (systolic pressure) 6. Repeat in the other arm

American Diabetes Association.

Diabetes Care

2003: 26; 3333 –3341.

Measuring the Ankle-Brachial Index (ABI) Step 4: Position the Cuff Above the Ankle Place blood pressure cuff just above the ankle of one leg, apply gel over the area of the dorsalis pedis artery

Dormandy JA et al.

J Vasc Surg

. 2000;31:S1-S296.

Measuring the Ankle-Brachial Index (ABI) Step 5: Measure the Pressure in the Dorsalis Pedis Artery

Dormandy JA et al.

J Vasc Surg

. 2000;31:S1-S296.

1. Place Doppler probe over the dorsalis pedis artery; inflate the cuff 2. Deflate the cuff; when the return of blood flow is detected, record this as the systolic pressure of the DP artery of that leg

Measuring the Ankle-Brachial Index (ABI) Step 6: Measure the Pressure in the Posterior Tibial Artery

Dormandy JA et al.

J Vasc Surg

. 2000;31:S1-S296.

1. Place gel and Doppler probe over the posterior tibial artery (below the cuff) 2. Measure the pressure, record as posterior tibial pressure for that leg

Measuring the Ankle-Brachial Index (ABI) Step 7: Repeat the Process in the Opposite Leg Repeat the same process in the other leg and record the pressures of the dorsalis pedis and posterior tibial arteries

Dormandy JA et al.

J Vasc Surg

. 2000;31:S1-S296.

Calculating the ABI

Right Leg ABI Left Leg ABI Higher right-ankle pressure

(DP or PT pulse)

=

Higher arm pressure

(of either arm)

=

Higher left-ankle pressure

(DP or PT pulse)

Higher arm pressure

(of either arm)

ABI Interpretation ≤ 0.90 is diagnostic of peripheral arterial disease

Hiatt WR.

N Engl J Med

. 2001;344:1608-1621.

Calculating the ABI Example Calculation

Right Leg ABI

60 mm Hg

=

120 mm Hg

Hiatt WR.

N Engl J Med

. 2001;344:1608-1621.

Left Leg ABI

66 mm Hg

=

120 mm Hg

Calculating the ABI Example Calculation Right Leg ABI 60 mm Hg 120 mm Hg

=

0.50

Left Leg ABI 66 mm Hg 120 mm Hg

=

0.55

ABI Interpretation ≤ 0.90 is diagnostic of peripheral arterial disease

Hiatt WR.

N Engl J Med

. 2001;344:1608-1621.

ABI Limitations

   Possible false negatives in patients with noncompressible arteries, such as some diabetics and elderly individuals Insensitive to very mild occlusive disease and iliac occlusive disease Not well correlated with functional ability and should be considered in conjunction with activity history or questionnaires

Interpreting the Ankle–Brachial Index

ABI 0.90–1.30

0.70–0.89

0.40–0.69

 0.40

>1.30

Interpretation Normal Mild Moderate Severe Noncompressible vessels Adapted from Hirsch AT. Family Practice Recertification. 2000;22:6-12.

Referring to the Vascular Lab

Caveats for referral to vascular lab

• • •

Assessment of the location and severity is desired Patients with poorly compressible vessels Normal ABI where there is high suspicion of PAD Vascular Lab Evaluation

•

Segmental pressures

•

Pulse volume recordings

•

Treadmill PAD Diagnosis

Indications for Referral for Vascular Specialty Care

  

Lifestyle-disabling claudication (refractory to exercise or pharmacotherapy) Rest pain Tissue loss Severity of ischemia

Summary

    PAD is a common atherosclerotic disease associated with risk of cardiovascular ischemic events and significant functional disability PAD can be effectively assessed in the primary care setting by primary care nurses The ankle brachial index is an effective and efficient measurement tool for diagnosis of PAD Early detection of PAD allows for appropriate disease management and decreased likelihood of ischemic events and disease progression

The Graying of U.S. Society

   Seniors 12.4 percent of the population Baby boomers will number 75 million 2030 – 20 percent will be over age 65 – 1/2 population > age 40

Nurse Competence in Aging Imperatives

    Moving to an aging society 85+ population > 8.9 million in 2030 Older adults – Utilize 50% of hospital days – 45% of the direct care – primary patient population of most specialty nurses. Geriatric preparation significantly improve health care to older adults.

Classifying the Elderly

   ages 65 to 74 - the young old ages 75 to 84 - the middle old ages 85 and older - the old old

Impact of Aging

      ↑risk of health ↑co-morbidities ↑ disabilities ↑dementia ↑seniors with chronic illness requiring care ↓quality of life

Age Related Changes

      Cardiac Pulmonary Renal Gastrointestinal CNS Integument

Cardiac Function

    Coronary artery blood flow – decreases 35% between ages 20 and 60. Cardiac output decreases Systolic and diastolic murmurs There is a decrease in cardiac responsiveness rate with exercise.

Cardiovascular Function and Aging

      Central and peripheral circulation decreases Aerobic capacity decreases about 1% per year Maximum heart rate decreases about 1 beat per year Maximum stroke volume decreases Maximum cardiac output decreases Peripheral blood flow decreases

Physiological Changes to the Body with Aging

    Heart muscle – Contractile strength and efficiency decreases – Left ventricular wall thickens Heart valves – fibrotic and sclerotic SA node and AV tracts – Infiltrated by fibrous tissue. Aortic and mitral valves – Calcify

Changes in Blood Vessels

    Veins and arteries – dilate and stretch – decreased strength and elasticity. Peripheral arteries – Tortuous – Less resilient. Aorta and large arteries – stiffen Aorta – may lengthen and become tortuous.

Blood Pressure Changes

   Systolic blood pressure – May rise disproportionately higher than diastolic.

Changes in the cardiovascular system – Direct effects on other organs. Hypertension – Atherosclerotic changes in blood vessels – May result in the loss of vision, renal

Strength Changes With Aging

 Maximal strength decreases  Muscle mass decreases  Total number and size of muscle fibers decreases  Nervous system response slows

Exercise and the Elderly

   1996 report 30% of the elderly exercise regularly. Results in decreased risk for a number of chronic and debilitating illnesses.  US Department of Health and Human Services Assess – Motivation. – Level of activity that a person is capable of doing, – Help him/ her to understand how to change

Health Care for the Elderly

  Include – health promotion, – disease prevention, – health maintenance Anatomical and physiological changes – cardiovascular respiratory – Genitourinary endocrine – Neurological – musculoskeletal skin