Assessment of the Peripheral Circulation: An Update for ...

Assessment of the Peripheral Circulation: An Updatefor Practitioners

This article describes the comprehensive assessment of the peripheral circulation. Withgreater understandingofhaemodynamics andthe mechanisms of circulatory dysfunction associatedwith disease and normal .processessuch as ageing, physical therapists are in abetter:,position to assess and treat .circulatoryimpairfnent.Since adequate circulation is fundamentalto function, circulatory assessment is t

an integral component of any assessment regardlessofwhether vascular dysfunction is aprimary problem. Some tests that are performedin peripheral vascular laboratories are described, as well as those tests that can easilybe performed by therapists. The interpretationof the results of these tests and the implicationsfor more rationa/physical therapy treatment aredescribed.

ELIZABETH DEAN

Elizabeth Dean, Ph.D., M.S., received a doctoral degree from the University of Manitoba (Physiology) anda Master of Science (Physical Therapy) from the UniversityofCalifornia, and is currently on faculty atthe School of Rehabilitation Medicine, University ofBritish Colombia, Canada. She has a particular interest in improving physical therapy assessment andmanagement of the cardiorespiratory system.

Many conditions encountered byphysical therapists can affect thecirculatory status of the upper and lowerextremities. These include thromboembolism, thromboangiitis obliterans,externalcompression, compartment syndrome, congenital abnormality ,neoplasm, trauma,connective tissuedisease, vasospastic disease andresponse to certain pharmacologic agentsand medications. The circulation to theupper extremity in particular can beimpaired by a cervical rib and an obstruction at the thoracic outlet. Thesigns and ·symptoms of connective tissue disease are often more apparent inthe upper than in the lower extremity.The lower extremity tends to be predominantly affected by arterial occlusive disease (AOD). The primary causeof occlusive disease is the deposit andaccumulation of atheromatous plaqueswithin the principal distributing arteries. As a result of this process the vessellumen becomes progressively narroweror stenosed and in some cases completely.occluded. Vessels supplying thelower limb, namely the abdominalaorta, the femoral, popliteal, and pos-

teriar tibial arteries are most commonlyaffected. Predilection of the disease for the lower limb is thought toreflect a difference in haemodynamicscompared with the upper limb.

Atherosclerotic changes of the· bloodvessel walls are accelerated with ageingand diabetes. Blood flow and pressure

~distal to the site of a resulting stenosismay be reduced, or completely absent(Carter .1972a). Atherosclerosis anddiabetic angiopathy are the principalcauses of ischaemia and surgical amputation of the lower.limbs. These conditions are worsened by smoking whichresults in constriction of the small bloodvessels..

When the blood supply toa limb isimpaired, neuromuscular function andexercise tolerance can be compromised(Larsen and Lassen 1966). Impairedexercise tolerance may reflect symptomlimitation due to localized arterial occlusive disease of the extremity, withor without involvement of the coronaryvessels. Evidence of occlusive diseasein the extremities suggests a higherprobability of coronary involvementthan in individuals without peripheral

vascular disease. In addition, a patientwith heart disease has a high probability of having peripheral vascular disease but may not report being symptomatic.

Frequently therapists are consultedto examine and treat patients with arterialocclusive disease as .a primarydiagnosis,or secondary to some otherdiagnosis. Patients referred to therapywith some other primary diagnosis mayhave undiagnosed peripheral vasculardisease. The therapist therefore needsto be aware of the importance of athorough vascular assessment, and· ofthe implications of treatment both onthe affected limb(s)as well as on thephysiologic demand on thecardiovas..cular system.

Many physical modalities used byphysical therapists arethought to affectblood flow. Traditionally caution hasbeen observed in applying heat modalities.AlI therapists are taught therudiments of temperature .testing of theskin to establish the integrity of theneurosensory pathways and avoid thepotential risk of burning the patient.Less attention, however, has been paid

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Assessment of thePeripheralCi rcu lation

to examination of the peripheral circulation to ensure that the resultingdemands on the local circulation canrespond to meet the supply andaccommodate peripheral run off. These circulatory parameters also need to beassessed to avoid potential hazard particularly to an already endangered is-

\chaemic limb.

Therapeutic exercise and facilitationtechniques can be expected to be lesseffective if inadequate circulation isprovided to the working muscles.. Dynamicand isometric exercise, for example, also physically stress the cardiovascular system. The adequacy ofmyocardial function to support theseefforts depends on the anatomic andphysiologic integrity of the myocardium, on the adequacy of the arterialsystem to supply the periphery anddrain into the venous system, and. onthe adequacy of the venous system$andthe muscle pumps to effect venous return.

Clinical .assessment of peripheralvascular status is therefore a fundamental skill of the practising physicaltherapist, and warrants evaluation inpractically every patient regardless ofwhether there is a primary diagnosis ofvascular insufficiency. The adequacyof the peripheral circulation can beevaluated at three distinct levels:1. ability to support the basal meta

bolic needs of peripheral tissues,2. ability to support peripheral tissues

in response to local and general exercise, or external heating; and

3. the ability to maintain adequatevenous return and cardiac output.

This article first describes some ofthe basic laboratory tests used to evaluate peripheral vascular status and theirsignificance, and then reviews the components of the clinical assessment. Em...phasis is given to objective evaluationas well as the role of subjective evaluation and its limitations. Certain traditional aspects of management of theischaemic limb are examined,and suggestionsare made for more rationalmanagement based upon vascularphYSiology.

laboratory TestsOver the past twenty years peripheral

vascular laboratories have emerged inmajor ·health care facilities. These laboratories are responsible for conducting a number of vascular studies of thearteries and veins to aid. in diagnosisand assessment. Valuable informationcan be gleaned from the vascular laboratory reports ~whichcan help therapists in treatment planning. These testscan provide such information as thepresence of arterial occlusion, its anatomical localization,an objectivemeasure of disease severity, baselinemeasurements for future comparisons,a guide to healing prognosis distal tothe site of occlusion, and an index ofthe development of collateral vessels.The types of tests conducted in theperipheral vascular laboratory includethe measurement of segmental bloodpressures, skin temperature assessment, and venous impedance plethysmography as an adjunct to venous assessment.. These will be brieflydescribed. A more detailed descriptioncan be found elsewhere (Carter 1972a,Juergens etal 1980).

Blood. Pressure StudiesAnkle systolic blood pressuremeas

urement is ·used extensively as a simpleand reliable index of arterial· occlusionin the lower extremity (Carter 1969,Strandness and Bell 1965). Ankle pressures less than 97 per cent of the brachial pressure are usually consideredabnormal ie 97 percent is the lowerlimit of·normal. In the individual withnormal circulation, ankle systolic pressure is· usually in excess of the brachialpressure as a result of systolic amplification of the pressure wave as itmoves distally. Segmental measurement of blood pressure at various levelsalong an upper or lower limb providesmore information regarding the specific localization of vessel narrowing orcirculatory impairment. As a generalguide to the interpretation of ankle systolic pressure for example, down to 40to 50.per cent of brachial pressure is

suggestive of stenosis or .a single occlusion; 50 per cent or lower is moreconsistent with multiple occlusions.Overlap of· these ranges does occur.Collateral circulation can develop tocounteract the effect of occlusion ofmajor arteries and maintain the bloodpressure.

Segmental pressures measured distally along the limb down to the ankleor wrist will usually be equal to orgreater than brachial pressure (Downset af 1975). Absolute pressures in thedigits are above 70 mmHgunder normal circumstances. A pressure below70 mmHg is suggestive of occlusion.Differences of more than 15mmHgbetween adjacent fingers and toes arealso considered·abnormal,and warrantfurther investigation.

It is important to note that pressureswithin the normal range when taken atrest do not rule out the presence ofmild arterial stenosis (Carter 1972b).The measurement of distal pressuresafter a standardized exercise test canhelp to .identify patients with mild disease.. Provided there are nocontraindications, .patients with suspected peripheral vascular insufficiency andwhose resting segmental pressures·approximate normal limits are asked toexercise to their limit in the exercisetest selected. Maximal effort is oftenlimited·by claudication pain in peripheral vascular disease. Ankle blood pressures recorded after exercise in a pa~

tient with occlusion will tend to· exhibita characteristic drop immediately postexercise. The extent of pressure dropand the time required for ankle pressures to return to pre-exercise measurements will reflect the severity of anyunderlying·stenoses or occlusions andpossibly the development of collateralcirculation. Thus measurements per...formed in conjunction with exercisetend to give more information aboutfunctional impairment than pressurestaken at rest. Normal pressure responses following exercise can also beeffectively used to rule out calf painsecondary to neuromuscular or or...thopedic conditions.

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Assessment of the Peripheral Circulation

Therapists are not encouraged toperform .segmental systolic pressuremeasurements using Doppler ultra..sound unless they have acquaintedthemselves fully with the methodology,the ranges of normal pressure and theinterpretation of pressures outside thenormal limits (MacKinnon 1983).Measur~ment error in any noninvasiveprocedure is a potential risk. The moredistal the site·of the pressure measurement the greater the probability ofmeasurement artifact and error. It iswell recognized, for example, that pressures recorded noninvasively in the toesand fingers are more influenced bychanges ·inblood flow and vasomotorstate. These factors can be moreeffectively controlled, and valid and accurate pressures obtained in aperipheral vascular laboratory.

Skin Temperature StudiesSkin temperature of a limb can be

measured objectively with thermistorsto provide an index of blood flow.Certain precautions have to be observed when using skin temperature asan index of vascular sufficiency ofalimb. First of all, skin temperature reflects blood flow of the cutaneous circulationonly. Little information canbe deduced from skin temperaturesabout the adequacy of the circulationto underlying tissues such as muscle ornerve which are of particular concernto therapists. Warm skin over an occluded site must be interpreted cautiously since this could reflect physiologic 'steal' of blood away from themuscle and deeper tissue to supply theskin. Secondly, the nutritional needsof the skin vis a vis blood flow areminimal compared with the flow seenby the cutaneous vasculature in response to the thermoregulation andmaintenance of core temperature.Thirdly, skin temperature and bloodflow are linearly related between 20°Cand 30°C. Disproportionately greaterflow is required, however, toeffeettemperature changes of the skin in excess of 30°C. Despite these restrictions,skin temperature can be a· useful tool

in establishing an index of blood flowand of the· reactivity of the peripheralblood vessels in response to changes invasomotor state. Normally with bodyheating and inhibition of sympathetictone of blood vessels, blood flow increases and skin temperatures mayap...proximate blood temperature. Bodycooling will normally produce vasoconstriction and.skin temperatures closeto room tempefature. Depending onthe severity of the arterial disease, thesefluctuations in peripheral skin temperature in response to vasodilatingandvasoconstricting stimuli are less apparent,and in severe cases may be completely absent. Althoughsympathectomy is less frequently performed thesedays as a means of effecting improvedcirculation toa limb, the use of theskin temperature test can help .establishthe function of the sympathetic nervesand potential outcome of a sympa,;.thectomy. In ADD or diabetic angio,;.pathy, for example, sympathectomy isnot indicated. Under these circumstances there is irreversible damage to theblood vessels that cannot -be ameliorated by severing the sympathetic nervesupply.

A sweat test is often performed inthe peripheral vascular laboratory in

_conjunction with a skin temperaturetest conducted during body warmingto examine sympathetic nerve functioning (Carter 1972a). The lower legs,for exampletare treated with iodineand powdered with corn starch. Blackspots appear where there is perceptiblesweating in the area tested. The presence of these spots provides an indicatlonof the function of sweat glandsand their sympathetic nerve supply.

Pulse Wave AnalysisOf the objective tests described, pulse

wave analysis is less well developed forroutine clinical use. Distal sensors suchas strain gauge, photoceU,and Dopplerultrasound transducer positioned overperipheral arteries, can produce a characteristic pulse wave configuration.These waves normally have a predictable upstroke, time-to-peak, down-

stroke, amplitude and width. Althoughthe characteristics of these parameterschange in .response to vasomotor .state,these changes are relatively predictable,and therefore can be controlled in thelaboratory for optimal comparison andanalysis of the pulse waves .

Occlusive and vasospastic diseasesare examples of disorders that producecharacteristic changes in pulse waves.The quantification of these changes andtheir interpretation need to be examined in greater detail and refined ifpulse wave analysis is to he used routinely in the assessment of peripheralvascular disease. With training, however, some visual impression of the severity of a stenosis can be obtained·bycomparing the pulse waves recordedfrom the same sites in the involved anduninvolved limbs.. Grossly abnormalwaves can be identified even if the disease is bilateral.

Doppler Venous StudiesRoutine tests in peripheral vascular

laboratories have concentrated largelyon the development of tests to assessthe status of peripheral arteries presumably because of the greater incidence of arterial disease compared withvenous disease. In recent years venousassessment has become more common.Doppler ultrasound techniques areproving to be a useful clinical tool inidentifying venous insufficiency particularly in the lower limbs.

Blood flow in peripheral veins hasspecific characteristics that are readilydetectable with Doppler ultrasoundtechniques and can be assessed to detect dysfunction of the venouscirculadon. On inspiration and expiration,for example, changes in abdominalpressure produce phasic changes in thevenous flow which can be detected asan audible signal with Doppler ultrasound.Marked increased abdominalpressure during the Valsalvamanoeuvre obliterates these sounds. Similarly, compression proximal to the siteunder examination interrupts flow.Distal compression of the limb normally augments the intensity of flow


Assessment of the Peri pheral Circulation

sounds. Venous obstruction is observed to reduce or obliterate flowsounds. Valvular incompetence produces reflux which can be readily detectedwith Doppler. Therefore, positioninga valve between the Dopplertransducer and compression site willestabIisp valve incompetence by thepresend¢ of retrograde flow. Thismethod is particularly useful· in the detection of .obstruction in deep veinssuch as the iliac, superficial femoraland popliteal veins.

MacKinnon (1983) has reported thatthe ·findings of therapists using DOppler ultrasound compared favorablywith the findings of angiography invenous disease as well as arterial disease. She· described the advantages ofa portable pocket size Doppler unit. asan assessment tool that was convenientto use by therapists.

AngiographyA bolus of radioactive contrastma

terial is injected directly into the bloodstream for purposes of visualizing eitherthe arteries (arteriography) or veins(venography) on X-ray. Angiographyis the single best, objective test to determine the .presence and severity ofarterial occlusion. The technique is invasive, therefore, potentially dangerous, and can be associated withmorbidity and in rare cases mortality.Although a beneficial diagnostic tool,arteriography in particular is reservedonly for cases in which future management is clearly dependent on thefindings of the test.

Physical ExaminationHistory

A detailed and precise history canoften establish the presence of vasculardisease. The essentials of the vascularassessment are shown in Figure 1. Acomprehensive history with ·particularattention to past history of cardio andperipheral vascular disease, is taken andthe findings compared with test reportsfrom the peripheral vascular laboratory if these are available. Clinical findings that corroborate the laboratory

results are reported in detail. Thepatient's past medical history, the courseof the presenting disorder and its response to medical or surgical interventionare also noted. The patient's medications should be reviewed sincecertain pharmacologic agents areknown to. have a vasoconstrictingeffeet and mimic the characteristic signsand symptoms of ADD.

A detailedhistbry of episodes of intermittent claudication, a commonsymptom of arterial disease especiallyin the lower extremity,must be obtained from the patient. During exercise, the metabolic demand of the muscles in the compromised limb cannotbe met by the blood flow provided.Metabolites accumulate and arethought to irritate nerve endings andproduce the sensation of pain. The patient complains ofa gripping, cramping sensation associated with the onsetof pain after a certain amount of walking(Skinner and Strandness 1967). Thisusually occurs in the calf muscle butcan extend up to the thigh and buttock.The patient usually reports that onslowing down or stopping the pain subsides. The distance the patient can walkis extremely variable ranging from afew steps to haIfa mile depending on

~disease severity. The absence of claudication pain, however,-does not completely rule out the presence of arterialocclusive disease. A patient's exercisecapacity may be limited asa result ofdeconditioning, cardiopulmonary disease or degenerative joint disease. Anyor all of these may limit the patientbefore muscle ischaemia develops.

In severe ADD, patients may complain of limb pain at rest. In such casesthe blood flow is inadequate to meetthe resting metabolic needs of the limb.In this situation the distal portion ofthe limb is usually affected first. Skinbreakdown, lesions and ulceration mayensue. Ischaemic rest pain is often reported to be worse at night particularlywhen the patient is in a recumbent position. Relief is frequently reportedwhen the limb is put in a dependentposition. This effectively increases the

hydrostatic pressure in the collateralvessels, ·decreases vessel resistance, increases flow and relieves pain. Careshould be taken to avoid confusing ischaemic pain or othet symptoms ofAODwith other neurologic, orthopedic or spinal cord conditions.

InspectionA keen sense of observation. ises

sential .when assessing the peripheralcirculation and distinguishing .arterialand venous insufficiency. Arterial andvenous diseases are distinct and do notnecessarily coexist. Examining for colour changes in the skin due to circulatory impairment can provide essentialinformation in making this distinction.The presence of rubor, pallor and cyanosis should prompt the therapist toidentify the underlying cause(s). Theexamination should include a review ofthe· bilaterality and the distribution ofany abnormal colouring,condition ofthe skin, the presence of hair growth,thinning of the skin,scalinessand translucency, disappearance of skin ridges,heaping of nail growth, ecchymosis,urticaria, petechiae, vessel compression, skin lesions, gangrene and deformities. Clinical signs that a:re characteristicof venous disease incJudepatches of skin discolouration over thelower leg,skin lesions over the calf andankle, ulcerations, healing of ,skin' lesions, infection, swelling, and oedemain response to limb dependency.Bilateral ankle oedema is more .. lik~ly toreflect systemic disease, thus right heartfailure must be ruled out.

PalpationA complete pulse assessment is the

basis for the peripheral vascular ~linical

investigation conducted bypis·t.Routinelypalpated peripheralarteries and palpation' sites are li~ted inTable 1.· ,

With practice, a thorough pulse as..sessment can be performed quickly andaccurately. The examining hand candevelop a sensitivity forapplYirig the

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Peripheral Vascular Assessment

HistoryPatient's NameAgeSex

Past Medical History (include DiabeticHistory: onset, management, progression, complications, patient education)VascularNonvascular

Past Surgical HistoryVascularNonvascular

Occupational History

Medication

Smoking History

Social History

Functional Status

Vital SignsHeart RateBlood PressureRespiration Rate

History of Limb Pain (Arterial Status)Duration of History of PainOnset StimulusType of PainDuration of PainDistance WalkedWhat exacerbates/relieves pain

Findings of Laboratory Tests· (ArterialStatus)Segmental Pressure Studies

Skin Temperature StudiesSweat Test

Pulse Wave Analysis

Arterial AssessmentInspection~·

Skin ColourColour Uniformity/DistributionTurgor (Dry/Scaly)Trophic Status. (Skin Translucency!Hair Growth)Lesions/GangreneOedemaMuscle BulkDeformitiesUnusual Markings

Palpation:Skin Temperature

Pulse Assessment (Strength)Upper Extremity:

Carotid ArteryAxillary ArteryBrachial ArteryRadial ArteryUlnar ArteryDigital Arteries

Abdominal Aorta

Lower Extremity:Femoral ArteryPopliteal Artery

Posterior Tibial ArteryDorsalis Pedis ArteryDigital Arteries

Auscultation:Upper Extremity:

Subclavian Artery

Lower Extremity:Femoral ArteryPopliteal Artery

Findings of clinical tests:Allen TestElevation/Dependency TestHyperabduction Test (upper extremity)Capillary Filling

Venous AssessmentFindings of Laboratory Tests:Venous Impedance Plethysmography

Inspection:Skin DiscolorationUniformity/DistributionLesions/UlcersScars/HealingInfectionSwellingResponse to Dependency

Palpation:Skin TemperaturePulses

Clinical Tests:Venous FillingVenous Filling Time

Figure 1: The essentials of the peripheral vascular assessment.

precise amount of pressure suff~cient

to penetrate overlying subcutaneoustissue 'and light enough not to occludethe paIpated artery. Ideally the therapist: .should use the index and middlefinge~s of the preferred hand to palpate. The use of the thumb should beav<?ided since normally it has a stronger

pulse which can override a weak pulseunder examination. Confusing a patient's pulse with that of the examinercan be avoided by the .examiner takingsimultaneously her/his own pulse. Inthe larger vessels, the strength of eachpulse is assigned a value from zero tofour (Table 2). The zero implies a pulse

is undetectable; one, the pulse is severely impaired; two, t~e pulse is moderately impaired; three, the pulse ismildy impaired; four, the pulse is normalin strength. An evaluation of thestrength of the pulse reflects the pulsepressure seen by the artery. In the presence of stenosis, the pulse isdimin-

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Assessment of the PeripheralCi reu lation

Table 1:Routinely palpated peripheral arteries and palpation sites

Table 2:Pulse strength and grade

Artery Palpation Site(Anatomical Position)

* To detect a pulse easily vessels need to be dilated or use a Dopplerpencil probe over sites. l

** Bruits occur more commonly at this site, and can be auscultatedhere accordingly"

Note: The arteries of the head and neck are not included..

ished, its amplitude decreased, the upstroke time is slower, an,d pulse widthis increased. On palpation, the pulsations may seem less pronounced. Theparameters ofa pulse on one .limb canbe compared simultaneously with thoseon the contralateral limb. The presenceof disease in the contralateral limb,however,should be ruled out if this isto be a useful comparison. Comparisonof a peripheral pulse with the apex beatcan establish the adequacy of pulsewave transmission, .and .provide an index of the pulse wave velocity.

The pulse rate deservesspecial.consideration.The use of the radial pulseas .an index of heart rate and generalmyocardial status is probably the mostwidely used clinical index. Theoretically,provided total obliteration of theartery has not occurred, any palpablepulse could be used for this purpose.The radial artery, however, takes relatively little experience to become adeptat .locating because of its superficial

Subclavian ArteryAxillary ArteryBrachial ArteryRadial::,.Artery

'I:

Ulnar ArteryFinger Digital Arteries

Abdominal AortaFemoral ArteryPopliteal ArteryPosterior Tibial ArteryDorsalis Pedis Artery

Toe Digital Arteries

Upper Limb

Supraclavicular Fossa* *Deep in axillaMidline or juslmedialln the antecubital fossaLateral one third of theanteri6r surface ofthe'wristMedial one third of the wristAntero-medial and ..Iatefal surfaces of thefingers*

Lower Limb

Deep over epigastrum**Groin, belowPoupart's ligament**Deep in popliteal fossa**Behind and beneath medial malleolusOver dorsum of the foot, medial to midline(variable)Postero..medial and .. lateral surface of thetoes*

and usually exposed position at thewrist. Other more deeply situated arteriesare inherently more difficult todetect even .without the complicationof superimposed vessel disease. Thelonger time period over which a pulseis counted, the more accurate the pulse.At rest,counting the frequency overthirty seconds and multiplying by twofor the minute rate is commonly used.The first pulsation should be countedas zero, the second as one and so forth.The reason for .this is that the· pulseto-pulse period represents one cardiaccycle rather than two.

Following exercise the pulse shouldbe counted over a short period of timesuch as ten seconds because of postexercise recovery and regression of thepulse rate to resting level. Followingmoderate to severe exercise in more fitindividuals this time may have to bereduced to six seconds because of atendency to recover immediately oncessation of exercise.

Pulse Strength Grade

Absent 0

Severely impaired 1

Moderately imp~ire_d 2Slightlyimpai~ed 3

Normal 4

The regularity of the radial pulse canhe monitored and described in termsof being regular, and intermittently orcontinuously irregular. An irregularpulse is usually indicative of a disorderof the rhythm of the heart rather thanpulse wave transmission. Some explanation should be found from the medicalhistory. If not, the referring physician or surgeon should be notifie~;L

-Skin temperature deternun'ations bypalpation may provide a rough indi~

cation of the cutaneous blood supply..Individuals vary considerably with respect to their skin temperatures, particularly of the hands and feet. Perhapsof greater relevance to the therapist, isthe comparative skin temper~ture difference between similar sites on twolimbs. The differences are likely to predict an actual difference in the bloodsupply to the two limbs. Temperatureis best detected by the more sensitivedorsal surface of the examiner's handwhich is moved slowly down the lengthof the limb. Arterial occlusion is usually reflected by a marked temperaturedecrease in the affected limb. An unusually warm area in one limb mayreflect good development of the col..lateral circulation. This is seen, for ex'"ample, over the knee of a patient whohas AOD that has developed over along period of time and the collateralcirculation has had sufficient time tocompensate.

AuscultationThe presence of·bruits can be de

tected by .auscultationwithastethoscope over principal sites (Table 1)" A

The Australian ,Journal of Physiotherapy. Vol. 33, No. 3, 1987 169


bruit is the term given to a murmurdetected with a stethoscope over ablood vessel and is suggestive of turbulent blood flow usually caused bysome degree of vessel narrowing. Bloodflow is normally undetectable with astethoscope unless flow is disrupted insomeway. For example, the traditionalKorotkoff sounds .auscultated on taking rout}neblood pressures reflect flowturbulence resulting from deformationof the brachiaLartery with.an occludingblood pressure cuff. Superficialarteriesmay be sensitive to the pressure of thestethoscope. Care must therefore betaken to ensure no artifact is introducedon examination.

Accurately recording brachial bloodpressure depends on several factors.The blood pressure cuffs availablethrough hospitals, clinics and medicalsupply houses are usually nylon andare secured around the limb by iVelcro.®The ideal cuff width is 20 percent greater than the diameter of thearm (Kirkendall etal 1967). Using acuff that is too small will tend to overestimate the actual pressure. Thebladder of the cuff should completelyencircle the arm which should be freeof any restriction from rolled upsleeves. The cuff is positioned over themid portion of the humerus at heartlevel, and wrapped to accommodate tothe contour of the arm. The cuffshouldnot .be' readily rotated on the arm, yettwo or three of the examiner's fingersshould .be easily inserted between thecuff and the patient's arm. The examiner palpates the brachial artery overthe antecubital fossa and places thestethoscope over the site. The cuff isinflated to 20 to 30 mmHg greater thanthe 'expected systolic pressure. Thepressure is released from the·cuff .at 2 'mmHg per second. Fast deflation ratescan seriously underestimate the bloodpressure, particularlY'in the patient atrest ora very fit individual. The pressure at which the first sound is heardis recorded as the systolic pressure, .andthe pressure at which .the sound disappears is usually recorded as the diastolic pressure. However, a third pres-

sure between the systolic and diastolicpressures can be measured at the pointwhere the sounds become muffled priorto disappearing entirely. As soon asthe diastolic pressure has been recorded, the cuff should be completelydeflated to avoid discomfort and venousengorgement of the limb. Whenever the. blood pressure measurementis repeated, the same arm and the sameconditions should be applied if thepressures are to be comparable. 'Attimes, performing simultaneousbilateral brachial pressures are indicated.Normally these are within a few mmHgof each other,however in the presenceof a cervical rib, thoracic outletsyndrome, or coarctation of the aorta forexample, discrepancies can arise.

Clinical TestsChanges in the colour of the skin in

r~sponse to different stimuli are important keys to the adequacy of theperipheral circulation. A slow rate ofreturn of colour following locally applied pressure to an extremity, for example, does suggest diminished circulation. Elevating the extremities mayelicit abnormal colour changes notnoted in the supine position. A positiveplantar pallor test may result in limbswith a stenotic or occlusive process onelevation of a limb. Further colourchanges may occur when the elevatedlimb is now placed ·in the dependentposition. Normally the return ofcolourin dependency occurs in about ten seconds or ·less. Inpatients with arterialinsufficiency there may be a delay 45to 60 seconds or more in the reappearance of normal skin colour.Prolonged dependency may produce furthercolour changes. Markedlyimpaired local blood flow may produceintense cyanotic rubor which may develop and subside slowly.

The Allen test is commonly used inevaluating more specifically the arterialsupply to the hand or foot and in assessingarterial occlusion. Both the circulation to the hand and foot are supplied by two main arteries. In principle,the test involves draining the hand, for

example, by elevating it for a coupleof minutes until it is noticeablyblanched compared with the otherhand. The therapist applies sufficientdigital pressure over both the radialand ulnar arteries simultaneously tocompletely occlude them. The arm islowered below heart level and the pressure over the ulnar artery is released.The therapist notes the pattern of distribution of blood .to the hand, thecolour changes, and the length of timefor complete return ofthe blood supplyto the fingers and palm, anteriorly andposteriorly. The test is repeated withthe ulnar artery occluded and the radialartery released. In the foot the test issimilarly performed alternately occluding its majoratteries,the dorsalis pedisartery and the posterior tibial artery.Although a relatively simple test to perform, the examiner .must ensure thatthe artery not being tested is completelycompressed. .

The 'disappearing pulse syndrome'can be clinically used to .. help detectarterial obstruction (De Weese 1960).The examiner determines the quality ofthe pulse distal to the site of suspectedocclusion at rest, for example, at theankle. Depending on whether bothlimbs are involved, both ankle pulsesmay be compared. The patient is thenasked to dorsiflex and plantarflexquickly for as long as possible up tothree minutes. The quality of the pulsesare again checked and compared. Thedegree of weakening or disappearanceof the pulse·is correlated with diseaseseverity.

The signs ofacervical rib or thoracicoutlet compression may be'aggravatedby a hyperabduction test of the arm.The examiner palpates the .peripheralpulse at the wrist, and then slowly abducts the arm its full range. The pulsetends to diminish or be obliterated inmoderately severe instances of proximal arterial compression with hyperabduction. The precise point in therange at which' the circulation to thearm is occluded can often be identified.

Capillary filling can give information regarding the nutritional status of

170 The.AustralianJournai of Physiotherapy. Vol. 33, No..3, 1987


the tissue. It can be examined readilyby the therapist applying pressure overthe nail bed in a single digit. Quickrelease will reveal a transitory blanching fonowed by increased rubor. Normally the return of capillary flow follows the release of focal pressureinstantaneously.

Astmple index of venous plexus filling tidIe in the periphery is the timefor blood flow to return following firmcompression of a distal site by an examining finger or thumb. Firm digitalpressure is applied to the skin for sevo.eral seconds. After removal of the finger, pallor is initially observed and followed by return of the circulationwithin two seconds if blood flow isnormal. A four or five second delaymay suggest impaired arterial inflow.Non-living tissue ina cyanotic, 1Schaemic limb will not exhibit transientpressure-induced pallor. The discolouration of the limb due to diseaseprobably signifies irreversible damageas a result of pregangrene or frankgangrene.

Homan's Sign has been ' commonlyused to establish a clinical diagnosis ofvenous thrombosis in the lower extremo.ity. This sign is characterized by a tendency to resist dorsiflexion of the ankle.Despite its common use, the reliabilityof the test is questionable. It may beabsent with deep vein thrombosis .yetpresent with other disorders such ascramps,sprains and arthritis.

Venous filling time of the superficialveins of the dorsum of the foot or thehand, can be assessed by raising thelimb above heart level until the convexity of the protruding veins is reo.duced by venous drainage. The examiner lowers the·elevated limb quicklyand observes the time taken to refillthe veins comparable to the pre teststate or the alternate limb. Visualization of venous filling is facilitated ifthe .patient is warm and the veins di..lated. Valvular insufficiency and venous regurgitation must be ruled outparticularly in the lower extremity, oth-

erwise re-engorgement of the superficial veins will reflect both arterial inflow and retrograde venous flow.

Peripheral oedema without complicting heart failure results from animbalance of arterial inflow and ven..ous outflow. Elevation with or withoutexternaIcompression, such as the useof elastic stockings ora Jobst compression unit, is often the treatment .ofchoice. Prior to advocating limb elevation, however, the adequacy of arterial inflow must be established, otherwise elevation may contribute toischaemia of the extremity. When indoubt or in the presence of mild arterial obstruction, Jobst treatmentsshould be performed with the limb inthe supine or even .dependent position.If the limb is moderately or severelyoccluded and peripheral pressures arelow, Jobst treatments are potentiallyhazardous and their necessity must bere-evaluated.Measurementsof limbswelling can be effectively performedwith a tape measure provided landmarks are meticulously observed andrecorded for the comparison of futuremeasurements.

SummaryDetailed clinical assessment of pe

ripheral vascular status provides thebasis for more rational physical therapy intervention and long term planning for patients with and without aprimary diagnosis of peripheralcirculatory insuffh;:iency. A comprehensivevascular assessment should establish theadequacy of the circulation to supportthe basal metabolic requirements ofthelimb, to support the demands of localand generalized exercise, or externalheating; and to maintain adequate venous return and cardiac output. Thisinformation can help optimize the selection of modalities and therapeuticexercise, the prediction ,of treatmentoutcome and long term treatment effectiveness.

A knowledge of peripheral vascularstatus can also provide an indicationof cardiovascular status and potential

exercise tolerance. These are essentialconcerns for any patient with suspectedvascular disease and the older patientwho is being considered for an exerciseprogramme.

A greater understanding of peripheral haemodynamics and its measurement should also aid the therapist intreating peripheral oedema and prescribing Jobst compression treatments.A knowledge of arterial and venouspressures and the effect 'of gravity onperipheralhaemodynamics suggeststhat limb elevation during a Jobsttreatment may not be optimal, and per..;haps potentially hazardous for somepatients. The decision to elevate a limbfor treatment can only be made on thebasis of the individual assessment findings of each patient.

Enhanced ability of the therapist todetect and evaluate the severity of arterial and venous disease has becomeincreasingly important and. relevant· asan assessment skill. The ageingpopulation, and the greater incidence of atherosclerosis, and vascular impairmentin the limb secondary to trauma inparticular, have placed greater demands on the physiotherapist to havea high degree of expertise in yascu.larassessment and to prescribe individualtreatments accordingly.

ReferencesCarter SA (1969), Clinical·measurement of systolic

pressures in limbs with arterial occlusive disease,Journal of the American Medical Association,207, 1869-1874. .

Carter SA (1972a) Investigation andtteatmentofarterial occlusive disease of the extremities, Clin"ical Medicine, 79, 13-24.

Carter SA (1972b),Response of ankle systolicpressure to leg exercise·in mild or questionablearterial disease, New England Journal of Medicine, 287, 578-582.

DeWeese JA (1960), Pedal pUlses disappearingwith exercise: a test for intermittent claudication, New England Journal oj Medicine, 262,1214-1217.

Downs AR, Gaskell P, Morrow I and MunsonCL (1975), Assessment of arterial obstructionin vessels supplying the fingers by measurementof local blood pressures and the skin tempera"ture response test ~ correlation withangiographic data, Surgery, 77, 530..539.

Juergens JL, Spittell JA and Fairbairn JF (1980),Peripheral Voscular Diseases, 5th edition, WBSaunders Co.• Philadelphia, pp 83-105, 139-215.

The Australian Journal of·Physiotherapy. Vot33, No. 3,1987 171


Kirkendall WM, Burton .AC and .Epstein ED(1967), Recommendations for human 'bloodpressure determination by sphygmomanometer,Circulation~ 36, 980-988.

LarsenOA and LassenNA (1966), Effect of dailymuscular exercise in patients with intermittentclaudication, Lancet, 2, 1093-1096.

MacKinnon JL· (1983), Study of Doppler ultrasonic vascular assessments performed by physical therapists, Physical Therapy~ 63, 30-34.

Skinner JSand Strandness DE Jr (1967), Exerciseand intermittent claudication. II Effect of physical therapy, Circulation, 36, 23-27.

StrandnessDE and Bell JW (1965),Peripheralvascular disease: Diagnosis and objectiveevaIuation .using a mercury strain .gauge, Annals ofSurgery, 161 (Suppi 4), 1-12.


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