Unit 4: Medical Technologies

- any format of machinery that is used to operate or perform medical procedures

To know if something is “wrong” you need to know what is “right”  Primary Vital Signs and Normal Ranges   A website that provides samples of normal and abnormal heart and breathing sounds

Primary Vital Signs - Allow for a basic assessment of body function 1. Temperature 2. Blood Pressure 3. Pulse (heart rate) 4. Respiratory Rate

 Each of these has a normal range, a range that’s common in 95% of the population  The normal range will vary with sex, age, fitness, ethnicity, etc.

1. Temperature  Proteins are affected by body temperatures, therefore we usually thermoregulate to maintain a constant core temperature (36.8 +/- 0.7)

 How do we thermoregulate?  When we are hot: we sweat, the hairs on our bodies lie flat and our blood vessels become wider (vasodilation)  When we are cold: we shiver, we get goose bumps to trap heat and we vasoconstrict

 High core body temperature can indicate  Infection (a temporary re-setting of the thermostat, part of non-specific immunity)  Hyperthermia (loss of thermoregulation due to heat stroke or drug reaction)

 low core body temperature (hypothermia) is normally due to exposure to low temperatures

2. Blood Pressure  Pressure exerted by circulating blood on the walls of the blood vessels  Composed of two readings  Systolic: maximal contraction (ventricular) of heart (115 mm Hg)  Diastolic: resting pressure (70 mm Hg)  115/70 is “normal”  playAnimation.aspx?gcid=000013&ptid=17 playAnimation.aspx?gcid=000013&ptid=17

 Measured using a sphygmomanometer  s/content/bloodpressure.html s/content/bloodpressure.html

hypertension  Blood pressure is abnormally high  A risk factor for strokes, heart attacks, heart failure  Shortens life expectancy Causes:  Very complex, but risk factors include sedentary life style, obesity, salt sensitivity

Classification Systolic pressureDiastolic pressure mmHg kPa kPa (kN/m 2 ) mmHg kPa (kN/m 2 ) Normal 90– –15.960–798.0–10.5 Prehypertensi on 120– –18.580–8910.7–11.9 Stage 1 140– –21.290–9912.0–13.2 Stage 2≥160≥21.3≥100≥13.3 Isolated systolic hypertension ≥140≥18.7<90<12.0 Source: American Heart Association (2003). [8] [8]

hypotension  Blood pressure abnormally low  Usually shows as dizziness, sometimes fainting  Can be due to hormonal changes, widening of blood vessels, side effects of medicines, etc.

3. Pulse (heart rate)  Physical expansion of the artery  Varies with age, in an adult beats per minute  Bradycardia: below 60 bpm  Tachycardia: above 100 bpm

4. Respiration Rate  Normal adult 12-2o breaths per minute

Age Normal heart rate (beats per minute) [15] [15] Normal respiratory rate (breaths per minute) [16] [16] Newborn [17] [17] –5 months –12 months –3 years –5 years –10 years –14 years years