Year 1 MBChB Clinical Skills Session CVS Blood pressure monitoring Taking upper body pulses

Transcription

1 Year 1 MBChB Clinical Skills Sessin CVS Bld pressure mnitring Taking upper bdy pulses Reviewed & ratified by: Dr V Taylr-Jnes and Ms C Tierney

2 Aims and Objectives Aim: Fr the student t be able t take a manual bld pressure and assess upper bdy pulses safely. Objective: T understand reasns fr measuring upper bdy pulses and bld pressure. Objective: T be able t accurately measure upper pulses and manual bld pressure. Objective: T link physilgy t practical skill by demnstrating changes assciated with exercise. Upper bdy pulse palpatin Thery and backgrund Bld pressure and pulse assessment are imprtant indicatrs f a patient s health. These are nrmally dne in cnjunctin with ther vital signs, such as respiratry rate r temperature. Vital signs indicate the patient s respnse t factrs which impact n bdily systems (i.e. cardivascular, respiratry, gastrintestinal, neurlgical) Factrs which influence bld pressure and pulses include: Physical e.g. Fluid intake and utput Psychlgical e.g. Anxiety, phbia Disease Infectin Trauma e.g. Cardiac, Respiratry e.g. Pneumnia, sepsis e.g. Bleeding, burns, fracture Envirnmental e.g. Temperature, pllutants Palpatin upper bdy pulses The upper bdy pulses we will palpate tday include: Radial pulse at the wrist Brachial at the elbw Cartid in the neck Details f each are given in a later sectin 2

3 Describing the pulse The pulse is described in respect t: The rhythm f the pulse is it regular r irregular? The pulse rate in beats per minute (bpm) if the rhythm is irregular this must be cunted ver a full minute, therwise 30 secnds and duble t give bpm. The vlume f the pulse r hw much bld passes thrugh the artery fr each cntractin f the heart. It may be described as weak r thready in a patient wh has lst a lt f their circulatin vlume f bld r in ne whse heart is failing as a pump. It may als be described as full r bunding in a patient wh is pregnant (due t an increase in circulating bld vlume), sepsis due t a reductin in resistance t bld flw r in a patient under sme frm f stress causing an increase in heart rate and cntractility. The character r feel f the pulse as it ebbs and flws. It is difficult t describe this finding (experience will make yu aware f the assciated changes) but different circulatry cnditins have a different feel t the pulse. Artic regurgitatin ccurs when the artic valve fails t clse prperly, the result is a sharp pulse which sharply increases and then cllapses away. This can be accentuated by raising the arm. The state (cnditin) f the vessel wall. Des the vessel fell sft and healthy r is it firm / hard due t the develpment f sclertic plaques within the artery? Starting the examinatin / Prcedure Intrduce yurself t the patient including yur name and that yu are a medical student (d nt frget t state yur year f study). Check the patient s name and date f birth t ensure yu are dealing with the right patient. Explain the examinatin (and the level f undress) t the patient and gain infrmed cnsent. Wash yur hands befre tuching the patient. The radial pulse The radial pulse is lcated n the lateral aspect f the lwer frearm just prximal (twards the centre f the bdy) t the wrist jint. It is pssible t assess the rhythm and rate f the pulse at the radial artery. Place yur fingertips nt the bny prminence just prximal t the wrist jint (radial stylid). Mve yur fingers medially (twards the midline and the tips f yur fingers will drp int a grve. Apply light pressure and slwly increase the amunt f pressure until yu feel the pulse. The pulses can be felt (palpable) when the artery is lightly cmpressed against the underlying radius (bne). See images belw. Radial artery 3

4 The brachial pulse The brachial pulse is lcated n the anterir surface f the arm at the level f the elbw jint. The artery is larger than the radial artery and in additin t the rhythm and yu will be able t determine Place yur fingertips nt the anterir surface f the elbw in the midline at the level f the jint. Have the patient slightly bend their elbw and mve yur fingers medially (twards the inside) and the tips f yur fingers will feel a large tendn. Mve yur fingers t the medial aspect f this tendn and ask the patient t straighten their arm. Apply light pressure and slwly increase the amunt f pressure until yu feel the pulse. The pulse can be felt (palpable) when the artery is lightly cmpressed against the underlying humerus and sft tissues. The brachial artery is deeper than the radial artery and requires a little mre pressure t cmpress it. See pictures belw. Cartid Pulse The cartid pulse is lcated n the anterir aspect f the neck just lateral (twards the utside f the bdy) t the larynx (vice bx). Psitin yurself slightly t the side f the patient. Place yur fingertips (sme practitiners may use their thumb) nt the anterir surface f the neck in the midline with yur index finger at the level f the Thyrid Cartilage (Adam s apple). Mve yur fingers laterally (twards the utside) apprximately cm and the tips f yur fingers will drp int a grve. Apply light pressure and slwly increase the amunt f pressure until yu feel the pulse. The pulse can be felt (palpable) when the artery is lightly cmpressed against the underlying tissues. The Cartid Arteries cntain pressure receptrs and yu shuld take care nt t press t hard. Yu MUST NOT palpate bth arteries at the same time and yu MUST NOT rub the Cartid Artery. See picture belw. 4

5 Bld Pressure measurement Indicatins fr taking a Bld Pressure (BP) Rutine- Regular checks shuld be made n hypertensive patients t assess treatment and lifestyle interventins. Any patient n admissin t hspital shuld have a BP taken. Patients wh are unwell, r having specific treatment fr example a bld transfusin shuld have their bld pressure mnitred regularly. A bld pressure shuld always be taken n bth arms when first meeting a patient. The reasning behind this practice is that there are smetimes imprtant differences between the tw readings, and that the lwer bld pressure in ne arm shuld be investigated as it may be a sign f an abnrmality (carctatin, stensis, dissectin). A difference f equal t r less than 10mmHg is acceptable and needs n further investigatin. Lying and standing BP s shuld be taken n first meeting the patient, if symptms indicate pstural hyptensin r histry f cllapse Bld Pressure Bld Pressure (BP) represents the amunt f pressure in the arterial system when the heart cntracts (systlic pressure) and when the heart is relaxed (diastlic pressure). Bld pressure is measured and recrded in millimetres f mercury (mmhg) using an instrument called a sphygmmanmeter. Arterial bld pressure measurement is ne f the mst cmmn prcedures undertaken in clinical practice alng with temperature, pulse and respiratry rate (vital signs). Accurate measurement f the BP is imprtant fr the clinical assessment and management f bth hypertensin (high bld pressure) hyptensin (lw bld pressure) Bld pressure readings are recrded with the systlic value preceding the diastlic value separated by a slash e.g 126/84 mmhg 5

6 The Sphygmmanmeter Cuff which is applied t the upper arm Dial graduated in mmhg Pressure release valve The cuff and bladder The cuff Bulb t allw inflatin f the cuff The cuff is an inelastic clth husing an inflatable bladder nrmally secured with Velcr fastenings. The imprtance f cuff size (fr bth manual r autmatic) shuld be nted; If it is t shrt r t narrw, the BP is falsely high If it is t lng r t wide, the BP is falsely lw Taking a manual bld pressure Starting the Prcedure Intrduce yurself t the patient including yur name and that yu are a medical student (d nt frget t state yur year f study). Check the patient s name and date f birth t ensure yu are dealing with the right patient. Explain the examinatin (and the level f undress) t the patient and gain infrmed cnsent. Wash yur hands befre tuching the patient. Seat the patient fr at least 3-5 minutes prir t the measurement whilst yu gather the equipment required stethscpe, sphygmmanmeter and alchl swabs. Clean the stethscpe with an alchl swab befre and after use, including the head f the stethscpe (rutinely) and the ear pieces shuld the stethscpe nt be yur wn. Place the sphygmmanmeter at the level f the patient s heart at a cmfrtable distance frm yu when yu are recrding the BP allwing yu t place the stethscpe nt the brachial artery and be able t see the dial f the sphygmmanmeter. Ask the patient t expse the arm nearest t the sphygmmanmeter and make sure the arm is cmfrtably supprted at the level as the heart. The arm shuld nt be cnstricted by tight clthing. Apply the cuff f the sphygmmanmeter s that the artery indicatr line verlies the brachial artery (fund by palpatin) t ensure the bladder is crrectly psitined n the upper arm. T ensure the crrect amunt f cmpressin the bladder within the cuff shuld encircle 80% r mre f the circumference f the upper arm but shuld nt verlap itself (BP cuffs have a size range, please ensure that when applied the crrect cuff is used (a 6

7 cuff which is t large will give errneus lw bld pressure and ne which is t small an errneus high reading). The lwer edge f the cuff shuld be psitined apprximately 2.5 cm abve ante-cubital fssa t ensure the head f the stethscpe des nt cme int cntact and create additinal nise as the cuff inflates and deflates. Cuff sizes T ensure the crrect amunt f cmpressin the bladder within the cuff shuld encircle 80% r mre f the circumference f the upper arm but shuld nt verlap itself (BP cuffs have a size range, please ensure that when applied the crrect cuff is used (a cuff which is t large will give errneus lw bld pressure and ne which is t small an errneus high reading). The lwer edge f the cuff shuld be psitined apprximately 2.5 cm abve ante-cubital fssa t ensure the head f the stethscpe des nt cme int cntact and create additinal nise as the cuff inflates and deflates. (*The range fr clumns 2 and 3 are derived frm the British Hypertensin Sciety. ** Large bladders fr arm circ. ver 42cm may be required) Taking a BP estimate Palpate the pulse at either the brachial r radial artery and inflate the bladder slwly feeling fr the disappearance f that pulse. Cntinue t inflate the cuff t mmhg abve the pint f pulse disappearance, then deflate the bladder slwly cntinuing t palpate fr the pulse Nte the pint at which the pulse can be felt again - this pint apprximates t systlic bld pressure (ur estimatin f systlic pressure) Deflate the cuff fully and quickly 7

8 Taking a BP -auscultate Nw that yu have an estimate f the systlic pressure we will use the measurement as a guide when we inflate the cuff. Wait at least 30 secnds between the estimate and frmal measurement f bld pressure. Place the stethscpe ver the brachial artery. Re-inflate the cuff t 20-30mmHg ver the estimated systlic Slwly deflate the cuff (apprximately at 2-3mmHg/secnd) whilst listening with the stethscpe fr tw cnsecutive taps (indicating systlic BP) These are knwn as Krtkff phase 1 this equates t SYSTOLIC bld pressure Yu will then hear Krtkff sunds 2,3 and 4 At the pint yu have cmplete disappearance f sunds this is Krtkff phase 5 and equates t DIASTOLIC pressure After all sunds have disappeared the cuff shuld be fully deflated, even if anther measurement is t be attempted >15 secnds shuld lapse befre attempting t repeat reading 8

9 The Krtkff sunds The sunds heard during measurement f bld pressure are nt the same as the heart sunds, if a stethscpe is placed ver the brachial artery in a nrmal healthy persn, n sund shuld be audible. As the heart cntracts these pulses laminar (nn-turbulent bld flw) is pushed thrugh the arteries, and n sund is prduced. Similarly, if the cuff is inflated t a pressure abve the patient's systlic bld pressure, bld flw ceases and n sund will be prduced. If the pressure in the cuff is reduced, when it reaches the patient's systlic bld pressure, the first Krtkff sund will be heard. This happens when the pressure in the artery rises during systle and bld is able t flw under the cuff. This bld initially flws in spurts resulting in turbulence which prduces the audible sund. As the pressure in the cuff reduces thumping sunds are heard whilst the pressure in the cuff is between the systlic and diastlic pressures. Eventually the sunds disappear altgether, as the pressure drps belw the diastlic bld pressure, the cuff n lnger restricts bld flw and the flw becmes smth again and prduces n audible sund. Phase (sund) 1 first appearance f tapping sunds which will gradually increase in intensity Phase 2 the sftening f sunds which may becme swishing in nature. Phase 3 the return f luder sunds Phase 4 the sunds becme muffled Phase 5 the sunds cease (silence) Taking a BP recrd Tell the patient abut their BP reading ne reading is insufficient t diagnse health, hypertensin r hyptensin, (please see NICE guidance). If yu were unable t identify either systlic r diastlic pressures, wait at least 15 secnds befre ding anther reading. In clinical practice BP findings will be recrded in the patient ntes r n an bservatin chart. Please ensure that results are reprted t the persn supervising yu and they shuld dcument the results. Why d we estimate the systlic? If yu have a patient suffering with hypertensin and yu d nt inflate the cuff high enugh yu will miss the true systlic pressure. A perid f silence belw the initial systlic phase (Krtkff 1) is fund in sme cnditins. 9

10 This is knwn as the Auscultatry gap (perid f silence) and may result in the systlic pressure being underestimated. Autmatic Bld pressure Autmated devices are used mre cmmnly in hspitals and primary care, patients shuld be prepared in the same way as with the anerid sphygmmanmeter. The machine shuld be plugged in, ensure the right cuff size and apply the cuff in the same way, then press the start buttn. The BP will be displayed n the screen alng with a heart rate. Cnsideratins; the heart rate reading shuld nt be used, the pulse shuld be cunted manually. The autmatic machines can be uncmfrtable fr the patient, and they can be affected r give inaccurate readings in patients with hyp r hypertensin, bradycardia r tachycardia. Factrs affecting bld pressure values Age: Abut 70% f peple aged ver 75 have hypertensin Gender: Prevalence is higher amng men than wmen up t age 64, ver 64 it is higher in wmen Race: Hypertensin is mre cmmn in Afr-Caribbeans Temperature: BP can increase with cld temperature Pain: Linked with hypertensin Emtin: BP can be increased with stress Alchl: Regular heavy alchl intake increases bld pressure Smking: Nictine present in tbacc prducts causes increased bld pressure and heart rate Exercise: regular activity helps t maintain the elasticity f the bld vessels which reduces BP Obesity: Bld pressure assciated with verall bdy mass. This is independent f errrs in measurement due t besity cuff artefact etc. 10

11 Surces f errr Sphygmmanmeter pr maintenance incrrect cuff applicatin incrrect bladder size tube/pump leakage Patient Obesity Arrhythmias Arm psitin The bserver pr technique bserver bias terminal digit preference (e.g 120/70 r 125/75 instead f real pressure: 122/72) nte: the scale is graduated in 2s - there is n 5 distance frm scale The patient shuld be less than 1metre away Dcumenting Results Please reprt abnrmal results immediately t a senir member f staff, and dcument clearly. Any abnrmal readings will need re testing. References and ther Useful Resurces Surces and useful resurces British Hypertensin Sciety Duglas, G., Nicl, N. And Rbertsn, C. eds., 2009, Macled s Clinical Examinatin 12 th editin, Lndn, Elsevier Natinal Clinical Guideline Centre hypertensin-full-guideline3 Natinal Service Framewrk fr Crnary Heart Disease 2000 O Brien, E. Jurnal f Human Hypertensin (1999) 13, WHO Guidelines n Hand Hygiene in Health Care 11

12 Peer Feedback 03 Y1 BP peer feedback.dcx Vide Glssary Arrhythmias abnrmal heart rhythms Auscultatry gap a perid f silence fllwing Krtkff phase 1 Bradycardic lw heart rate Diastlic bld pressure resting pressure within the bld vessels when the heart relaxes (diastle) t fill with bld prir t the next systle. Hypertensin High bld pressure levels Hyptensin Lw bld pressure levels Krtkff phase 1-5 Sunds heard during bld pressure recrdings, Krtkff 1= systlic, 4-5 = diastlic mmhg millimetres f Mercury Pstural hyptensin Bld pressure falls n standing Sphyg sphygmmanmeter Systlic bld pressure maximum pressure reached in the bld vessels and is due t ventricular systle when the heart pumps bld int the arterial Tachycardic fast heart rate 12