IA 07: Vital Signs Flashcards
Why is measuring body temperature important?
- used to screen for illness and infection
- allows clinicians to make clinical decisions relating to diagnosis, planning of investigations, and initiation of medication therapy
- important monitoring endpoint to assess patient response to drug therapy
What is normal oral body temperature?
36.5ºC-37.5ºC
How do you convert temperature?
- ºC = (ºF – 32) x 5/9
- ºF = (9/5 x ºC) + 32
What temperature is considered fever or pyrexia?
- > 37.5ºC (oral)
- > 38ºC (rectal)
What temperature is considered hyperpyrexia?
> 41.0ºC (oral)
What temperature is considered hypothermia?
< 35.0ºC (oral)
How do body temperature measurements differ depending on the route?
- rectal is 0.5ºC higher than oral
- axilla and temporal are 0.5-1.0ºC lower than oral
- tympanic is 0.5-1.0ºC higher than oral
What are the 6 types of thermometers?
- digital thermometer
- tympanic thermometer
- temporal artery thermometer
- infrared contactless thermometer
- forehead thermometer
- basothermometer
Digital Thermometer
- route
- use
- pros
- cons
route:
- oral, rectal, axilla
use:
- used with or w/o probe cover
- probe needs to be positioned properly (depending on location) for accurate reading
pros:
- cost-effective
- readily available
- quick (10 s)
- used for multiple routes
cons:
- invasive
Tympanic Thermometer
- route
- use
- pros
- cons
route:
- tympanic
use:
- uses sensor probe to measure infrared heat produced by tympanic membrane (shares its blood supply with hypothalamus)
- probe needs to be positioned in external auditory canal (EAC) at appropriate angle
pros:
- non-invasive
- immediate results
- validated in sedated patients
cons:
- $$
- difficult to use in young infants (EAC curves upwards)
- accuracy dependent on correct technique
Temporal Artery Thermometer
- route
- use
- pros
- cons
route:
- forehead
use:
- measures naturally emitted infrared heat from temporal artery
- forehead is scanned in temporal artery region and behind ear using direct skin contact
pros:
- non-invasive
- more accurate than tympanic measurements (but less than rectal)
cons:
- requires skin contact
- $$
- not readily available
Infrared Contactless Thermometer
- route
- use
- pros
- cons
route:
- forehead
use:
- uses a sensor probe to measure infrared emitted heat
- every device has different instructions (ie. distance to hold from patient)
pros:
- non-invasive
- non-contact (prevent cross contamination)
- immediate results
cons:
- $$
- accuracy is dependent on technique
Forehead Thermometer
- route
- use
- pros
- cons
route:
- forehead
use:
- plastic strip is held against forehead for 1-2 minutes
pros:
- non-invasive
- inexpensive
- can be used from birth
cons:
- inaccurate
Basothermometer
- route
- use
- pros
- cons
route:
- oral, vaginal, rectal
use:
- used to predict ovulation (highest fertility 2-3 days before basal body temperature rises
- take basal temperature immediately upon waking
- use the same route each time
pros:
- inexpensive
cons:
- may need to use in combination with other fertility awareness based methods
What route should body temperature be measured from birth to 2 years old?
- screening: axillary or temporal
- definitive: rectal
What route should body temperature be measured from 2-5 years old?
- screening: axillary, tympanic, or temporal
- definitive: rectal or temporal
What route should body temperature be measured is older than 5 years?
- screening: axillary, tympanic or temporal
- definitive: oral or temporal
What should you consider when choosing a route to measure body temperature?
- is definitive temperature reading necessary to make a clinical decision
- patient-specific factors – age, patient preference, clinical status
What are the pharmacological options to manage fever?
- acetaminophen
- ibuprofen
What is the dosing for acetaminophen?
- < 12 years old: 10-15 mg/kg/dose po q4-6h prn (max 60-75 mg/kg/24h)
- ≥ 12 years old: 325-650 mg po q4-6h prn (max 4000 mg/24h)
What is the dosing for ibuprofen?
- < 6 months: refer to physician
- 6 months to 12 years old: 5-10 mg/kg/dose po q6-8h prn (max 40 mg/kg/24h)
- > 12 years old: 200 mg po q4h prn or 400 mg po q6-8h prn (max 1200 mg/24h)
What are the non-pharmacological options for management of fever?
- cold compress
- cold or tepid bath
- wear breathable fabrics
- remove excess clothing and bedding
- increase fluid intake to replace insensible water loss
- use a fan
- bed rest, avoid physical exertion
- maintain ambient temperature around 20.0 – 21.0ºC
When should fever be referred to a physician or hospital? (6)
- fever > 37.5ºC + lethargy, confusion, delirium, etc.
- fever > 40ºC
- any fever in a patient < 6 months of age
- any fever associated with stiff neck, seizures, localized pain, swelling, redness
- any fever present > 24 hours without any obvious cause
- any fever present > 72 hours
What are the factors that affect body temperature? (6)
- time of day
- body location
- age
- ovulation
- stress (physical or emotional)
- drinking hot or cold beverages, chewing gum, and smoking may affect measurement of body temperature
Factors Affecting Body Temperature
Time of Day
- early morning ≈ 35.8ºC
- late afternoon ≈ 37.3ºC
Factors Affecting Body Temperature
Body Location
- rectal is 0.5ºC higher than oral
- axilla is 0.5 to 1.0ºC lower than oral
- tympanic is 0.5 to 1.0ºC higher than oral
Factors Affecting Body Temperature
Age
- wider variations in infants
- mean body temperature declines with age (≈36ºC)
Factors Affecting Body Temperature
Ovulation
0.3 - 0.6ºC increase at ovulation (until menses)
Describe the technique to measure oral temperature.
- clean thermometer with alcohol or put a clean probe cover on thermometer
- confirm with patient: no hot/cold beverages ~15mins prior, no smoking ~15mins prior
- place thermometer probe beneath the tongue in posterior sublingual pocket
- ensure patient’s mouth remains closed, without biting down on thermometer
- leave thermometer in place until beeps (~10-20 secs)
Describe the technique to measure axillary temperature.
- clean thermometer with alcohol or put clean probe cover on thermometer
- expose patient’s axilla
- place thermometer probe into apex of axilla
bring patient’s arm down and close to torso (to stabilize) - leave thermometer in place until beeps (~20-30 secs)
Describe the technique to measure temporal temperature.
- remove protective cap (if applicable)
- place probe flush (or flat) on the center of forehead
- press and hold SCAN button
- gently sweep the thermometer either left or right from the centre of forehead to the hairline, keeping the sensor flat and in contact with the skin for the entire scan (2-3 sec)
- once the hairline is reached, release the SCAN button, lift the thermometer from the head and read the display
Describe the technique to measure tympanic temperature.
- turn thermometer on
- clean thermometer with alcohol or put clean probe cover on thermometer
- ensure the external auditory canal is free of cerumen
- straighten ear canal by pulling the pinna: > 3 years old = back and up, < 3 years old = back and down
- ensure probe fit is snug and sealed
- aim infrared beam at tympanic membrane
- leave thermometer in place until beeps (~1 second)
Describe the technique to measure rectal temperature.
- ensure correct positioning of patient: adults = lie down on one side with hip flexed, infants = lie face down across caregiver’s lap
- clean thermometer with alcohol
- apply water-soluble lubricant before insertion
- insert 3-4 cm into anal canal
- leave thermometer in place until it beeps (~10secs)
- clean thermometer with alcohol again
Describe the technique to measure basal temperature.
- always use the same method (oral, rectal, vaginal)
- measure first thing in the morning before getting out of bed (ie. before moving)
- avoid speaking, eating, or drinking before/during measurement
- slight elevation in temperature (~0.3-0.5ºC) occurs after ovulation
- highest probability of conception is in the days prior to or day of ovulation
What is a pulse?
- heart contracts and pumps blood through arteries
- pumping action causes blood to pound against artery walls
- creates a pressure wave felt in periphery as a pulse
Assessment of pulse should always include descriptions of what?
- heart rate
- rhythm
- force
Why is pulse rate measurement important?
- may provide information about how well the heart is working (ie. is the heart pumping enough blood, is the heart rhythm irregular)
- allows clinicians to make clinical decisions relating to diagnosis, planning of investigations, and initiation of medication therapy
- important effectiveness and/or safety monitoring endpoint to assess patient response to drug therapy
What is the resting heart rate of newborns?
70-170
What is the resting heart rate of 1-6 year olds?
75-160
What is the resting heart rate of 6-12 year olds?
80-120
What is the resting heart rate of adults?
60-100
What is the resting heart rate of elderly?
60-100
What is the resting heart rate of conditioned athletes?
50-100
What is bradycardia?
abnormally slow heart rate
What is tachycardia?
heart rate exceeding normal range
What should arrhythmia be assessed via?
auscultation
What is pulse force assessed via?
palpation
What is the 4-point scale describing pulse force?
- 0: absent
- 1+: weak, thready
- 2+: normal
- 3+: full or bounding
What are the factors affecting pulse? (8)
- age
- air temperature
- body position
- gender
- emotions
- exercise
- medications
- pathology
Factors Affecting Pulse
Age
↓ pulse rate with ↑ age
Factors Affecting Pulse
Air Temperature
- ↑ pulse rate with ↑ temperature to transfer heat from body
- ↓ pulse rate with ↓ temperature to preserve core temperature
Factors Affecting Pulse
Body Position
↓ pulse rate when going from sitting to standing
Factors Affecting Pulse
Gender
pulse rate women > men
Factors Affecting Pulse
Emotions
anxiety, fear, anger, stress
Factors Affecting Pulse
Medications
- ↓ HR: beta-blockers, calcium channel blockers
- ↑ HR: inotropes (ie. epinephrine), levothyroxine, caffeine, cocaine
Factors Affecting Pulse
Pathology
- ↓ HR: hypothyroidism
- ↑ HR: cardiac conditions (ie. arrhythmias), volume depletion, infection/fever, pain
Describe the technique used to measure brachial pulse.
- located at the anterior aspect of the elbow, medial to biceps tendon
- used to assess pulse force and rhythm
Describe the technique used to measure radial pulse.
- located at the radial side of the wrist
- used to assess pulse rate and rhythm
- less useful for pulse force
Describe the technique used to measure carotid pulse.
- located over carotid artery, on either side of neck
- palpate along the medial edge of the sternocleidomastoid muscle, under the angle of the jaw
- use a very light pressure
- often used during resuscitation or to detect carotid stenosis
- good for assessing pulse force
Describe the technique used to measure temporal pulse.
- located over temporal artery, in the temple area on either side of the head
- most easily palpated just in front of the upper part of the ear
- rarely used as a pulse site, but may be used to monitor circulation or take a temporal artery temperature
Describe the technique used to measure pedal pulse.
- located over the dorsalis pedis (DP) and tibialis posterior (TP) arteries on the foot
- DP: palpate on the dorsal aspect of the foot, lateral to the extensor hallucis longus tendon (which runs from the big toe towards the ankle)
- TP: palpate behind the medial malleolus (the rounded protuberance of bone) of the inner ankle
- often used to assess peripheral vascular disease
Describe the technique used to measure apical pulse.
- auscultate over the chest where the heart’s mitral valve is best heard (lub-dub)
- in adults: auscultate at the fifth intercostal space (between rib bones) at the left midclavicular (collarbone) line
- in infants and young children: auscultate at the fourth intercostal space at the left midclavicular line
- often used to measure heart rate in CV assessment – pulse deficit = apical pulse – peripheral pulse
- infants and children (< 5 years)
- obese patients
Assessment of respiration should always include description of what?
- respiratory rate
- pattern
Why is respiratory rate measurement important?
- useful to identify changes to and abnormalities in respiration, which may be associated with both respiratory and non-respiratory conditions
- change in respiratory rate is often the first sign of deterioration as the body attempts to maintain oxygen delivery to tissues
- allows clinicians to make clinical decisions relating to diagnosis, planning of investigations, and initiation of medication therapy
- important effectiveness and/or safety monitoring endpoint to assess patient response to drug therapy
What is the normal respiratory rate in 0-6 month olds?
30-60
What is the normal respiratory rate in 6 month to 1 year olds?
20-35
What is the normal respiratory rate in 1-5 year olds?
20-30
What is the normal respiratory rate in 6-14 year olds?
18-25
What is the normal respiratory rate in adults?
12-20
What is the normal respiratory rate in elderly?
12-20
What is bradypnea?
abnormally slow respiratory rate
- caused by neurological disturbances, electrolyte imbalances, narcotic overdose, post-anesthesia
What is tachypnea?
respiratory rate exceeding normal range
- caused by trauma, injury, stress, pain, respiratory disease, cardiac disease
What is apnea?
absence of respirations
What is kussmaul?
caused by metabolic acidosis, diabetic ketoacidosis, renal failure
What are the factors that affect respiratory rate? (7)
- age
- gender
- altitude
- stress
- exercise
- medications
- pathology
Factors Affecting Respiratory Rate
Age
- ↑ lung capacity with age (↓ respiratory rate needed to exchange air)
- ↓ lung elasticity with age
Factors Affecting Respiratory Rate
Gender
lung capacity in men > women
Factors Affecting Respiratory Rate
Altitude
rate and depth of respirations ↑ at higher elevations to compensate for ↓ O2 content in the air
Factors Affecting Respiratory Rate
Stress
pain, anxiety, infection, fever
Factors Affecting Respiratory Rate
Medications
- ↓ RR: narcotics
- ↑ RR: sympathomimetics (ie. cocaine, ephedrine, amphetamines)
Factors Affecting Respiratory Rate
Pathology
- ↓ RR: brain injury, hypothyroidism, heavy alcohol consumption
- ↑ RR: respiratory distress (ie. asthma exacerbation), infection, stress, anxiety
What are the 3 techniques for measuring respiratory rate?
- inspection
- palpation
- auscultation
Describe the inspection technique to measure respiratory rate.
- auditory: only if patient has audible, laboured breathing
- visual: watch chest or abdomen
Describe the palpation technique to measure respiratory rate.
place hand over thorax, shoulder blade, or abdomen
Describe the auscultation technique to measure respiratory rate.
- useful for patients with shallow breathing
- place stethoscope over anterior triangle of neck or over thorax
What is blood pressure dependent on?
- cardiac output
- systemic vascular resistance
What is systolic blood pressure?
maximum BP during left ventricular contraction (systole)
What is diastolic blood pressure?
resting pressure that blood exerts between ventricular contractions while heart fills with blood (diastole)
Why is blood pressure measurement important?
- primary objective of identifying, treating, and monitoring BP is to reduce risk of CV disease and its associated morbidity and mortality
- allows clinicians to make clinical decisions relating to diagnosis, planning of investigations, and initiation of medication therapy
- important effectiveness and/or safety monitoring endpoint to assess patient response to drug therapy
What is a ‘normal’ blood pressure?
≈ 120/80 mmHg
What is a ‘high’ blood pressure?
≥ 135/85 mmHg
What is a ‘low’ blood pressure?
no specific range
What are symptoms of ‘low’ blood pressure?
- fatigue
- dizziness, light-headedness, fainting (syncope)
- decreased concentration
- blurred vision
- nausea
- cold, clammy, pale skin
What are the factors affecting blood pressure? (9)
- age
- gender
- ethnicity
- diurnal rhythm
- circulating volume status
- weight
- exercise
- emotions
- medications
Factors Affecting Blood Pressure
Age
↑ throughout childhood until adulthood
Factors Affecting Blood Pressure
Gender
- female = male before puberty
- female < male after puberty
- female > male after menopause
Factors Affecting Blood Pressure
Diurnal Rhythm
- lowest in the AM
- highest during afternoon or early evening
Factors Affecting Blood Pressure
Circulating Volume Status
- ↑ BP: hypervolemia
- ↓ BP: hypovolemia
Factors Affecting Blood Pressure
Weight
excess body weight correlates with ↑ BP
Factors Affecting Blood Pressure
Exercise
↑ BP with increased activity
Factors Affecting Blood Pressure
Emotions
↑ with pain, anxiety, fear, anger, stress
Factors Affecting Blood Pressure
Medications
- ↑ BP: corticosteroids, decongestants, NSAIDs, antidepressants
- ↓ BP: antihypertensives, diuretics
Measuring Blood Pressure
- create quiet and distraction-free environment
- ensure patient is positioned appropriately – seated, legs uncrossed, feet flat on ground, back supported
- check patient to ensure: resting for ~5mins, no eating, smoking, and exercising for ~30mins, no restrictive clothing or jewelry, has not taken dose of antihypertensive(s)
- ask patient not to move/speak during BP measurement
Describe the technique to measure automatic blood pressure.
step 1: cuff placement
- select the correct cuff size: cuff bladder width ≈ 40% of upper arm circumference, cuff bladder length ≈ 80% of upper arm circumference
- palpate brachial artery
- cuff position: bladder centered over brachial artery, bottom of cuff ~½-1 inch (or 2.5 cm) above antecubital space, snug fit (one finger under cuff), supported, at heart level
step 2: take BP
- press START/STOP button to turn unit on
- cuff will automatically inflate and tighten
- wait until cuff deflates and results are displayed
Describe the technique to measure manual blood pressure.
step 1: cuff placement
- palpate brachial artery
- cuff position: bladder centered over brachial artery, bottom of cuff ~½ - 1 inch (or 2.5 cm) above antecubital space, snug fit (one finger under cuff), at heart level
- ensure manometer is in direct line of eye sight
step 2: maximum inflation level
- palpate radial artery
- rapidly inflate cuff until pulse disappears
- read pressure on gauge
- add 30 mmHg to observed pressure
- deflate cuff rapidly
- wait 15-30 seconds before taking BP
step 3: auscultate BP
- place bell or diaphragm of stethoscope over brachial artery
- form a gentle but tight seal on skin
- inflate cuff rapidly to pre-determined level
- deflate cuff slowly at a rate of ~2-3 mmHg per second
- listen for Korotkoff sounds: (1) phase I – faint, clear, tapping (SBP), and (2) phase V – disappearance of sound (DBP)
- continue listening 10-20 mmHg below disappearance point
- deflate cuff rapidly to 0 mmHg
What are the 5 phases of Korotkoff sounds?
- phase I: faint, clear, tapping (SBP)
- phase II: swishing
- phase III: knocking
- phase IV: muffling
- phase V: disappearance of sound (DBP)
