Thermal Regulation Flashcards
*Core temperature & Ways to Measure
Temp of deep tissues of the body, remains fairly constant
Avg. Temp 98.0F and 98.6F
Measure: rectal, vaginal, bladder, oral, tympanic
*Skin Temp & Ways to measure
Rises and falls w/ temp of the surroundings
Measure: Axillary skin of forehead
*Fahrenheit to Celsius
98.6F
100.4F
104F
37C
38C
40C
Conversion of Celsius to Fahrenheit
C* (9/5) + 32
example 39C to F
39*(9/5)=70.1
70.1+32= 102.2F
Heat Production is a byproduct of ____ and is determined by….?
metabolism
determined by: muscle activity thyroxine E NE increased cellular activity Metab of digestions and storage
What acts as the bodys insulation?
Skin, subcutaneous tissues, fat, in cold minimal blood flow to extremities to heat internal organs
*Types of Heat Loss
Radiation- in the form of infrared heat rays
Conduction- loss in form of kinetics, transfer of heat through physical contact
Convection- removal of heat by air currents
Evaporation- loss of heat d/t water evaporating off skin, occurs even when not sweating- INSENSIBLE LOSS (cannot be controlled)
after exercise sweating can be controlled though
*Heat loss much greater in water than air
Types of Sweat glands
eccrine- all over body, innervated by SNS
aporcine- in genitalia and armpits, stinky puberty sweat
*Role of Sweat in Regulation of Body Temp
controlled via the Sympathetic Nervous System
evaporation of sweat if skin temp > temp oof surroundings can be lost by radiation, conduction, and convection
When surrounding temp>body temp body gain heat via radiation and conduction–under these conditions the body can only rid heat via evaporation
*Role of Hypothalamus In Regulation of Temp
Thermostatic detection here
- Heat sensitive cells
- signals skin to sweat
- triggers vasodilation
- decrease heat production (inhibits shivering)
- Cold sensitive cells
- piloerection (goose bumps)
- Vasoconstriction
- Increase heat production (shivering)
*Slide 27
*Hyperthermia Presentation
Heat cramps
Heat Exhaustion
Heat Stroke
Heat Cramps
- treatment
- cause
painful, easily treated
cramping in larger muscle groups caused by replacement of water w/o adequate salt resulting in low Na+
treated w/ cooling meausres, iv fluids, and electrolyte replacement
Heat Exhaustion
- treatment
- cause
serious but no organ damage
salt or water depletion in face of heat stress
mild hyperpyrexia, nausea, vomiting, light headedness,
treated w/ cooling measures, iv normal saline and possible electrolytes
Heat Stroke
- treatment
- cause
critical organ damage, significant mortality
body temp >105F
Multisystem failure, pt confused and hostile, tachycardia, tachypnea, decreased BP
treatment: cooling measures (
2 Types of Heat Stroke
Exertional- younger, physically fit w/ normal thermoregulation. dehydrated
Classic: older, exposed passively to thermal stress over hours/days
profoundly dehydrated
- Hypothermia presentation
core temp
Treatment of Hypothermia
Passive external rewarming
Active external rewarming:
- warm blankets, radiant heat, warm bath, warm air
- warm trunk 1st and minimize use of peripheral muscles (so the cold blood isnt pushed back into trunk)
Active Internal Rewarming:
- pleural and peritoneal irrigation w/ warm saline
- hemodialysis and cardiopulmonary bypass
- warm humidified O2
- warm IV fluids
- Bladder or GI irrigation w/ warm saline
Factors influencing Metabolic Rate
Exercise, food intake, shivering, anxiety
Basal metabolic rate Definition
energy output of the body to perform metabolic functions
Factors influencing BMR
food intake
thyroid hormone
activity level
age
Calorie
amount of heat energy required to raise the temp of 1g of h20 1C
nutritional calorie is 1000Calories or kCal
Caloric requirements for weigh maintenance, loss, and gain
M- neutral energy balance, input and output match
L- negative energy balance, output exceeds input
G- positive energy balance, intake exceeds output
Anabolism and Catabolism
- anabolism- build up, requires energy (ATP)
ex. making fat of extra nutrients you eat
-catabolism- break down energy production (ATP), ex. digestion
ATP is an energy currency*
*ATP as energy currency
nutrients are used by ALL cell to synthesize ATP, used as an energy currency for nearly all cellular functions
- produced via oxidation of proteins carbs and fast (ATP)
- utilized by all cells for transport, muscle contraction, molecule synthesis, cell division/growth, etc (ADP+P)
Carb Metabolism
glycolysis and gluconeogenesis
Fat Metabolism
absorbed into intestinal lymph via chylomicrons
chylomicrons empty into the juncture of jugular and subclavian veins
chylomicrons removed from blood in adipose tissue and liver via lipoprotein lipase
triglyceride released from chylomicron and broken down into fatty acid and glycerol- - then able to diffuse into fat cells and muscle cells
- E, NE, Cortisol, Glucocoritcoids, GH, Thyriod Hormone cause rapid mobilization of fat
protein metabolism
protein broken down into AA in GI tract and absorbed into the blood,
enter cells and form “new” proteins
GH and Testosterone increase protein
Glucocorticoids decrease proteins in tissue
- There is constant equilibrium between cell proteins, free AA, and plasma proteins
- Cells reached limit of stored proteins, excess AA degraded in liver and used for energy OR stored as fat/glycogen
*What is BMI?
How to calculate BMI
measurement of body fat based on height and weight
Calculation:
BMI=Mass KG/ Height (M^2)
BMI=Mass LB/ Height (IN^2)(703)
Parameters of BMI
39 extremely obese
*Recommended Daily Allowance
defines the intake that meet the nutrient need of almost all healthy persons in a specific age and sex group
- *advise people about the level of vitamin and nutrient intake to prevent disease
*Calories in:
proteins
carbs
fats
P- 4kCal/G
C- 4kCal/G
L- 9kCal/G
