Vital Signs

Vital SignsElizabeth Stephens, RNClinic@windsor.eduVital SignsPulseRespirationsTemperatureBlood PressureOxygen Saturation (not covered in this lecture)Pain (not covered in this lecture)PulseThrobbing sensation that can be palpated over a peripheral artery or auscultated over the apex of the heart.

Normal pulse rate for adults or adolescents is 60-100 bpm.PulseWith each heart beat the left ventricle contracts and forces blood into the aorta. Closure of the heart valves creates the sounds heard.

The forceful ejection of blood by the left ventricle produces a wave that is transmitted through the arteries to the periphery of the body.Circulatory System ControlBlood flow is adjusted according to O2 needs based on changing metabolic activity of different tissues.

What happens to circulatory system when there is stimulation of sympathetic nervous system? Sympathetic inhibition?Circulatory System ControlBaroreceptors, located in the walls of the carotid sinus and arch of the aorta also influence the vasomotor center.

Decreased circulating volume stimulated these receptors, which then transmits signals to the vasomotor center to stimulate the SNS. Resulting cardiovascular responses divert blood flow to vital organs.TachycardiaPulse of 100-180 bpm.

Sustained tachycardia will lead to decreased cardiac output.

Stressful situations: hypoxia, exercise, fever.

CHF, hemorrhage, shock, dehydration, and anemia produce tachy as a compensatory response to poor tissue oxygenation.

BradycardiaLess than 60 bpm.

Can be normal, r/t meds, pathologic (decreased thyroid activity, hyperkalemia, cardiac conduction blocks, and increased ICP).

When should you be concerned about bradycardia?Rate influenced by:1.) Exercise- increased activity- heart beat increased 20-30 bpm to meet bodys needs. Should return to normal in about 3 minutes after activity has stopped.

2.) Age- younger you are, faster the rate.

3.) Sex- females- 10 bpm more rapid than males

4.) Physical condition- athletes slower as a result of more efficient circ. system.

*HR increases with stimulation to SNSTerminologyArrhythmia- irregular heartbeat rhythm. Can be too fast or too slow. Malfunction of the hearts electrical system.

Pulse amplitude- refers to the quality of the pulse and is indicative of left ventricular strength.

Rhythm of pulse- the time interval between each heartbeat. Described as regular or irregular.

Dysrhythmia- irregular pulse patternTerminologyPulse deficit- occurs when apical pulse and peripheral pulse do not match.

PMI(point of maximum impulse)-5th intercostal space, midclavicular line on left side of body. Apical pulse.Assessment SitesApical- auscultated over the apex of the heart using stethoscope.-count for a full 60 seconds- necessary when giving certain medications (digoxin, BB, ACE inh.)Peripheral SitesRadial- thumb side, inner surface of wrist. *Palpated most frequently because most accessible.

Brachial- antecubital, inner medial surface of elbow. You can palpate and auscultate to listen to B/P.

Carotid- either side of trachea. *Assessed in cardiac arrest to determine adequacy of perfusion.

Temporal-temples of the forehead.Peripheral SitesFemoral- midway in groin. *Assessed in cardiac arrest for perfusion.

Popliteal- back of knee.

Dorsalis pedis-place fingers just lateral to the extensor tendon of the great toe. If cant feel pulse, move fingers more laterally.Peripheral SitesPosterior tibial- place fingers behind and slightly below medial malleolus of ankle. May be difficult to feel in obese or edematous patients.

When would it be important to palpate a pedal pulse?

Doppler US used when pulse cannot be palpated to determine presence or absence.

Pulse GradingDepends on degree of filling in the artery during systole (ventricular contraction) and emptying during diastole (ventricular relaxation).

0=absent+1= weak+2=diminished+3=strong+4= full and boundingRespirationsProcess of bringing O2 to body tissues and removing CO2. Lungs play a major role in this.

Another respiratory function is to maintain arterial blood homeostasis by maintaining the pH of the blood. Accomplished by breathing.

Respiratory cycle involves both inspiration and expirationRespirationsInspiration-active process in which diaphragm descends, the external intercostal muscles contract, and the chest expands to allow air to move into the tracheobronchial tree.

Expiration- passive process in which air flows out of the respiratory tree.Respirations# of complete cycles per minute comprise the respiratory rate.

Norm is 12-20 cycles/min

What are some factors that affect RR?

Depth and rhythm are also assessedDepth and RhythmResp. center in medulla and level of CO2 in blood control this.

Peripheral receptors in the carotid body and aortic arch also respond to level of O2 in the blood.

Depth- varies from shallow to deep

Diaphragm and intercostal muscles primary used for breathing. Accessory muscles: abdominal, sternocleidomastoid, trapezius and scalene (if necessary).TerminologyEupnea- normal breathing. Almost invisible, effortless, quiet, automatic and regular.

Tachypnea- rapid RR usually shallow in depth. Caused by increased metabolic demand (COPD patients). 24 or more rpm.

Bradypnea- decrease in RR. May have pathological cause or can be side effect of meds. 10 or less rpm.TerminologyApnea- periods without respiration.

Dyspnea- difficult, labored respirations. COPD.

*Observe physical characteristics of chest expansion. Normally expands symmetrically without rib flaring or retractions. Any observations of chest deformities (ie. barrel chest).Assessing Respiratory RateMonitor and record respirations immediately after taking pulse, as the patient will not be aware that you are observing respirations.

Observe the rise (inspiration) and fall (expiration) of the chest. This counts as on breath.

The respirations should be counted for a full minute to be accurate.Assessing Respiratory RateObserve the breathing: is the patient mouth breathing, pursing the lips on expiration, using accessory muscles, or flaring the nostrils?

Note the pattern and the depth of breaths.Blood PressureMeasurement of the force of blood against the arterial walls

The heart generates pressure during the cardiac cycle to perfuse the organs of the body with blood.

How does blood flow?Blood FlowFrom the heart to the arteries, into the capillaries and veins, and then flows back to the heart.

Blood FlowArteries-begin with the aorta, the large artery leaving the heart.

-carry O2 rich blood away from the heart to all of the bodys tissues.

-they branch several times, becoming smaller and smaller as they carry blood further from the heart.

* B/P in the arterial system varies with the cardiac cycle, reaching the highest level and the peak of systole and the lowest at the end of diastole.

Blood FlowCapillaries-small, thin blood vessels that connect the arteries and veins.

-their thin walls allow O2, nutrients, CO2 and waste products to pass to and from the tissue cells.

Blood FlowVeins-blood vessels that take O2 poor blood back to the heart

-become larger and larger the closer they get to the heart

-the superior vena cava is the large vein that brings blood from the head and arms to the heart, and the inferior vena cava brings blood from the abdomen and legs into the heart.7 Main Factors Affecting B/P1.) Cardiac Output- the force of heart contractions (the amount of blood ejected by the heart)- esp. affects systolic pressure.

2.) Peripheral Vascular Resistance- resistance to the flow of blood is due to the resistant vessels under the influence of the autonomic nervous system. most important determinant of diastolic pressure.7 Main Factors Affecting B/P3.) Elasticity and Distensibility of Arteries- elasticity refers to the action of the blood vessel walls to spring back after blood is ejected into them.

-both elasticity and distensibility decrease with age, resulting in increased systolic pressure and slightly increased diastolic pressure.7 Main Factors Affecting B/P4.) Blood Volume- when it is increased it causes an increase in both systolic and diastolic B/P, whereas decreased blood volume causes the reverse effect.

-Hemorrhage decreases B/P, whereas overhydration from excessive blood transfusions may cause an increase in B/P.7 Main Factors Affecting B/P5.) Blood Viscosity- the thickness of blood influences blood flow velocity through arterial tree.

-Increased viscosity with polycythemia, increases resistance to blood flow, whereas decreased viscosity, resulting from anemia, decreases resistance.7 Main Factors Affecting B/P6.) Hormones and Enzymes- important influence.

-Epinephrine and norephinephrine produce a profound vasoconstrictor effect on peripheral blood vessels (mediators of SNS). What will this do to B/P?

-Aldosterone (released by adrenal cortex), renin (released by the juxtaglomerular apparatus of the kidney), and angiotensin (activated by the renin response), raise B/P.7 Main Factors Affecting B/P Hormones and Enzymes (continued)

Histamine and acetylcholine (parasympathetic mediator) cause vasodilation. What does this do to B/P?

7 Main Factors Affecting B/P7.) Chemoreceptors- in the aortic arch and carotid sinus are sensitive to changes in the PaO2 (80-100 mmHg), PaCO2 (35-45 mmHg), and pH (7.35-7.45).TerminologySystolic pressure- measurement of the force on the arterial walls as the left ventricle contracts. This heart contracting is the top number.

Diastolic pressure- measurement of the force on the arterial walls as the left ventricle relaxes. This heart relaxing is the bottom number.

TerminologyPulse pressure- the difference between the systolic and diastolic pressure. Represents the force that the heart generates each time it contracts. So if resting B/P is 120/80, pulse pressure is 40.

The sounds heard during B/P assessment are called Korotkoff sounds.

-the first sound or beat represents systolic pressure.

-a change or cessation of the loud distinct sounds represents diastolic pressure.TerminologyPeripheral resistance- describes the resistance to blood flow resulting from the arterioles always being partially contracted.

-this allows continuous blood flow into the capillaries

-the elasticity of the artery walls combined with arteriole resistance helps maintain normal B/PHormonal Mechanisms Affecting B/PThe SNS stimulates the heart and constricts blood vessels resulting in a rise in arterial pressure.

The PNS depresses cardiac function and dilated selected vascular beds.

Circulating catecholamines, the renin-angiotensin system, vasopressin (antidiuretic hormone), atrial natriuretic peptide, and endothelin.

*All exist to maintain homeostasisCardiac OutputHas direct effect on B/P

CO= stroke volume (amount of blood ejected with one contraction) x HR/min.

Increased CO = increased B/P and vice versa

Heart normally pumps about 5L blood/minNormal B/PLess than 120/80

Wide range of normal, baseline readings are critical

Elevation or fall of 20-30 mmHg is significantTerminologyHypertension- sustained B/P above normal. 140/90 and above. Major risk for heart disease and stroke.

White coat hypertension- the office blood pressure is high, but ambulatory pressures are normal. Said to be a conditioned anxiety response.

-anxiety at time of measurement-presence of nurse or physician-prior diagnosis of hypertensionTerminologyHypotension- below normal B/P. May be normal, may be pathologic. Relatively low levels of blood pressure should always be interpreted in the light of past readings and the patients present clinical state.

When should you be concerned?

Orthostatic/postural hypotension- occurs when B/P drops during rising to a sitting or standing position. Common in older adults. A drop in systolic of 20 mmHg or greater or in diastolic of 10 mmHg or greater within 2 minutes of standing. Obtaining B/PManual B/P is assessed with stethoscope and sphygmomanometer. Accurate readings depend on appropriate cuff size.

Width of inflatable bladder should be 40% of upper arm circumference (12-14 cm in average adult).

Length of the inflatable bladder should be 80% of upper arm circumference (almost long enough to encircle arm).Obtaining B/PBe sure cuff is appropriate size for client (a cuff that is too narrow results in erroneously high readings; a cuff too large may result in false low readings.

Provide a quiet and calm environment.

Explain procedure to client.

Place client in relaxed reclining or sitting position.

Assess if client has smoked or exercised within the last 15 minutes.

Obtaining B/PAllow client to rest several minutes before beginning a reading.

Client should be instructed not to cross legs or talk during procedure (client activities and slouched position can yield false high readings).

Expose upper part of clients arm and position it with palm upward, arm slightly flexed with the whole arm supported at heart level (if arm is below heart it can be higher than normal, above heart can be lower).Obtaining B/PMost common site is brachial artery.

-When would you choose an alternative site?Obtaining B/PRadical Mastectomy

Dialysis shunt/AV fistula/ PICC line

Obesity

Any recent surgeries on the arm.Obtaining B/PWith arm at heart level, center the inflatable bladder over the brachial artery. The lower border of the cuff should be at least 2.5 cm above the antecubital crease. Secure the cuff snugly.

To determine how high to raise the cuff pressure, estimate the systolic pressure by palpation. As you feel the radial artery with the fingers of one hand, rapidly inflate the cuff until the radial pulse disappears.

Obtaining B/PRead this number on the manometer and add 30 mmHg to it. Now use this number as the target for subsequent inflations, prevents discomfort from unnecessarily high cuff pressures as well as occasional error caused by ausculatory gap.

Deflate the cuff promptly and completely and wait 15-30 seconds.Obtaining B/PNow place the stethoscope lightly over the brachial artery.

Inflate the cuff quickly again to the level just determined, and then deflate it slowly at a rate of about 2-3 mmHg per second. Note the level at which you hear the sounds of at least two consecutive beats. This is the systolic pressure.Obtaining B/PContinue to lower the pressure slowly until the sounds become muffled and then disappear. To confirm the disappearance of sound, listen as the pressure falls another 10-20 mmHg. Then deflate the cuff rapidly to zero. The disappearance point is the best estimate of true diastolic pressure.

Avoid slow or repetitive inflations of the cuff, because the resulting venous congestion can cause false readings.TemperatureNormal oral temperature is said to be 98.6 degrees F or 37 degrees C.

Can fluctuate depending upon time of day, morning can be lower and evening may be higher.

Rectal temps are higher than oral by an average of 0.7-0.9 degrees F or 0.4-0.5 degrees C.TemperatureAxillary temps are lower than oral temps by approx. 1 degree. Are considered less accurate than other measurements.

Tympanic membrane is a quick, safe and reliable practice if performed properly.

No oral temps when patient is unconscious, restless, or unable to close their mouths. Ask about hot and cold liquid consumption and smoking before oral temp taken.TerminologyPyrexia- elevated body temp (fever). 100.4 degrees F oral temp.

Hyperpyrexia- extreme elevation in temp. Above 41.1 degrees C or 106 degrees F.

Hypothermia-abnormally low temp, below 35 degrees C or 95 degrees C.Abnormal TemperaturesCauses of fever: infection, trauma, surgery, malignancy, blood disorders such as acute hemolytic anemia, drug reactions and immune disorders.

Causes of hypothermia: chief cause is exposure to the cold. Others are: reduced movement (ie paralysis), interference with vasoconstriction from sepsis or excess alcohol, starvation, hypothyroidism, and hypoglycemia.