Week 4: Vital Signs Flashcards
(26 cards)
Vital Signs
Vital signs are measures of the body’s core ability to stay alive
-pumping blood through the heart
-breathing
-maintaining a core temperature
Vital signs are the most frequently measured objective data for monitoring vital body functions and are often the first and most important indicator that the
patient’s condition is changing.
4 vital signs are internationally recognized and accepted in medicine
- Respiration (ventilation)
- Pulse or heart rate (HR)
- Blood pressure (BP)
- Temperature
3 other signs may be considered
- Pulse oximetry
- Pain rating scales
- Level of perceived exertion
Vital signs are used to establish
-Baseline physiological information to guide exercise program development
-Physiological response to activity to guide continuation, modification, or discontinuation of an exercise program
-Patient’s/client’s immediate health risk (physiological risks, contraindications
and/or improvements)
-Emergency cardiac or respiratory interventions
Vital signs can be affected by many external environmental factors and physiological factors.
These factors include, but are not necessarily limited to:
-age
-physical activity
-emotional status
-physiological status (including medications)
-clinician accuracy - skill
-equipment accuracy - calibration
-environmental temperature, barometric pressure, and humidity
Heart Rate (HR)
Goal = to determine the client’s physiological response to activity
To obtain an accurate picture of a client’s cardiac response to an activity, we
typically assess:
-Resting HR (5 minutes before activity)
-Activity HR (during or immediately following activity)
-Recovery HR (1 to 5 minutes post-activity)
Heart rate (pulse) is an indirect measure of the rate and rhythm of the contraction of the left ventricle.
3 characteristics are documented for HR
- Rate (bpm)
- Rhythm
- Intensity
-Count begins with the first beat that occurs after the time interval has begun
(“one count method”)
-HR is a measurement of beats per minute therefore, you should count for one full
minute *especially first time measurement
-Once you have established a baseline pulse rate (and it is regular and strong) you can use the 30 seconds x 2 method
Rhythm is documented as either:
-Regular – heartbeats at a fixed interval.
-Regular-irregular – a heart rate that occasionally ‘skips a beat.’
-Irregular-irregular – a highly disorganized heartbeat.
Intensity is documented on a scale of 0-3
-0 = absent
-1 = weaker than expected or thready; may be difficult to palpate
-2 = normal; able to palpate with normal pressure
-3 = bounding, may be able to see pulsation; doesn’t disappear with palpation
Factors that may affect heart rate
-Age: The pulse rate decreases as age increases from infancy to adulthood.
-Sex: After puberty, the average male pulse is lower than the average female’s.
-Fever: Pulse increases with fever due to the increased metabolic rate and peripheral vasodilation that occurs.
-Pain: Pain will increase the rate of a person’s pulse.
-Stress: Sympathetic nervous system stimulation from stress (e.g., fear, anxiety, and the perception of pain) increases the heart rate.
-Digestion: The increased metabolic rate during digestion will increase the pulse rate.
-Medications: Medications may either increase or decrease the pulse rate.
-Hypovolemia: Blood loss will typically increase the pulse rate from sympathetic nervous system stimulation.
-Hypoxia and hypoxemia: When oxygen levels decrease, cardiac output increases to attempt to compensate, resulting in an increased pulse rate.
-Electrolyte balance: Changes in potassium and calcium affect pulse rate and rhythm.
Measuring HR- Carotid Pulse
Caution, if you decide to assess the carotid pulse:
-Stand on the same side of the carotid artery you are assessing (never reach across)
-Do not press too hard
-Carotid sinus reflex = massage-like actions can decrease HR and produce bradycardia
-Never palpate bilateral carotid arteries, this can potentially cut off blood supply to the brain
Measuring HR- Radial and Brachial Pulse
- Support the left arm on a stable surface or with your arm at the level of their heart with their elbow extended and forearm supinated
- Using your 2nd and 3rd digits, palpate gently for the:
* brachial pulse: medially on the elbow crease
* radial pulse: 1-2 cm above the wrist crease, lateral to the flexor tendons - Measure the number of beats in 1 minute
- Record your findings in beats per minute (bpm)
Safety- HR and Exercise
-HR increases with progressive workloads at a rate of approx. 10 bpm per 1 metabolic equivalent of a task (MET)
-HR should decrease by at least 12 beats during the first minute of recovery
-HR should decrease by 22 beats by the end of the second minute of recovery
Respiratory Rate (RR): *Ventiliation
The normative respiratory rate for adults is 12-20 breaths per minute. Respiratory rate is observed and documented in three ways:
- Rate: # breaths per minute (bpm)
- Pattern
-eupnea: a ventilatory rate within normal limits
-tachypnea: an elevated ventilatory rate
-bradypnea: a low ventilatory rate
-apnea: absence of ventilation - Mechanics
RR- Mechanics
Inspiratory to Expiratory Ratio (I : E ratio)
-Ratio of time for inspiration versus expiration
-Normal is 1:2 or 1:3
-In obstructive disease, the expiratory time is increased because the patient has increased expiratory resistance, and it takes longer to empty the lungs before the next breath.
-Percentage of diaphragmatic vs. lateral costal versus apical (Normal is diaphragmatic >=70%, lateral costal <= 30%, apical = trace)
-Any use of the accessory muscles for ventilation (e.g., SCM, scalenes, upper
trapezius, pectorals), is a sign of increased work of breathing
-Any signs of distress (e.g., nasal flaring, stridor)
Factors Affecting Respiratory Rate and Depth
-Age: respiratory rate decreases with age through late adolescence, when it stabilizes.
-Exercise: respiratory rate and depth increase with exercise.
-Illness processes: cardiovascular disease and hematologic disorders such as anemia cause an increased respiratory rate. Sickle cell disease reduces the ability of hemoglobin to carry oxygen, resulting in increased respiratory rate and depth. Respiratory diseases can be manifested by difficulty breathing, use of accessory muscles, increased rate, and more shallow depth. Smoking alters airways, resulting in an increased rate.
-Medications: some medications, such as narcotics and general anesthesia, slow
respirations. Alternatively, drugs such as amphetamines and cocaine increase respirations. Bronchodilators slow the respiratory rate by dilating the airways.
-Pain: acute pain increases respiratory rate while decreasing respiratory depth
-Emotions: fear or anxiety can cause increased respiratory rate and decreased depth
Blood Pressure (BP)
-Blood pressure is a physiological variable which reflects the effects of cardiac
output, peripheral vascular resistance and haemodynamic factors.
-Use of a blood pressure cuff is an indirect measure of the pressure inside an artery caused by blood flow through the artery.
-BP is recorded as millimeters of mercury (mmHg).
-Systolic Pressure: the pressure at the time of contraction of the left ventricle.
-Diastolic Pressure: the pressure at the time of ventricular filling (‘resting’ pressure).
Blood Pressure Measurement
Korotkoff’s Sounds: assessment of blood pressure by auscultation, using a sphygmomanometer and a stethoscope:
-the systolic pressure is indicated by the first faint clear tapping sounds heard upon gradually releasing the air in the cuff (Phase 1)
-the diastolic pressure is indicated by the disappearance/cessation of all sounds (last sound heard- Phase 5)
Safety- Blood Pressure
-SBP increases with increasing workloads at a rate of approx. 10 mm Hg per 1 MET
-Normally no change in DBP or slight decrease during exercise
-Post-exercise SBP returns to pre-exercise levels or lower by 6 minutes of recovery
Korotkoff Sounds
Phase I: First clear tapping sound heard, often faint at first but increasing. The initial flow of blood through
the artery as the constriction of the artery is released; this is the systolic BP.
Phase II: Softer sound, may be a swishing sound or murmur. No clinical significance has been
determined.
Phase III: Louder and more crisp sound. No clinical significance has been
determined.
Phase IV: Sound changes from crisp and
distinct to muffled.
Some consider this the first
diastolic BP; useful during
exercise assessment and when phase V is not detectable.
Phase V: Cessation of sound. Diastolic BP
Blood Pressure and Exercise (Warnings)
BP changes during exercise or other high-level activity serve as serious warnings. These signs include the following:
-Systolic reading greater than 250 mm Hg
-Diastolic reading greater than 115 mm Hg
-A drop in the systolic pressure of more than 10 mm Hg from baseline
-Failure of the systolic pressure to increase with an increasing workload
STOP: Any one of the above BP findings should result in immediate cessation of activity
Blood Pressure Measurement Errors (7)
- Inappropriate cuff size: can over- or underestimate BP; errors tend to be greater when inappropriately small cuffs are used, causing added constriction
- Tested arm unsupported: muscle contraction required to hold arm in place can increase BP readings
- Legs crossed while sitting: may increase systolic by 2–8 mm Hg
- Unsupported sitting: may increase diastolic by 6 mm Hg
- Arm that is not level with heart: when the arm hangs down by the patient’s side
(below heart level), BP readings tend to appear falsely high. When the arm is above the patient’s head (above the heart level), BP readings tend to appear falsely low. Total differences (above or below heart level) may be 10 mm Hg or more. - Rapid deflation of the cuff during auscultation prior to the fifth Korotkoff: Underestimates systolic BP and overestimates diastolic BP sound
- Equipment malfunction such as change in calibration of aneroid units, valve or
air bladder leaks, or stethoscope defects: Results in various errors in readings - Auditory errors due to incorrect placement of stethoscope, external
noise, internal noise (tubing), or operator error (difficulty hearing
sounds): Results in inability to assess BP or in readings that overestimate or underestimate actual BP
Oxygen Saturation
-Percent saturation of arterial oxygen (SpO2) = estimate of how much oxygen
is travelling through your body in your red blood cells
-Normal range = 95% - 100%
-Pulse oximeter can estimate saturation, indirect non-invasive measure (pulse
oximeter is placed on a client’s index finger and uses light beams to estimate the oxygen saturation of the blood)
-Exercise-induced hypoxemia = decrease in SpO2 greater than or equal to 5% during exercise
Factors that affect oxygen saturation (3)
- Lung disease
- Decreased circulation
- Hypotension
Measuring SpO2 using a pulse oximetry can be influenced by (6)
-low perfusion or low pulse wave
-hemoglobin abnormalities
-low oxygen saturation
-very dark skin tone
-nail polish and acrylic nails
-movement during exercise
Rate of Perceived Exertion (RPE)
The rate of perceived exertion (RPE) is a valuable tool for subjectively monitoring a client’s ability to tolerate exercise. Two scales are commonly used in clinical practice:
1) the Borg Scale, which rates exercise intensity from 6 to 20
2) Category-ratio scale (CR10 scale), which uses a 0-10 scale (see images below).
Relatively healthy adults will reach their limit of fatigue at an RPE of 18-19 (very, very hard). For this course, we will be using the BORG.
