Special Topics In Physiology Flashcards
Detected Temperature < Set-Pint Temperature:
Example:
Heat Generating Mechanism
Example: shivering, thyroid hormone production, dec sweating, piloerection, skin vasoconstriction(alpha1), brown fat in babies(bet3)
Regulation of body temperature is mediated by
Hypothalamus
Set-Point Temperature < Detected Temperature
Example?
Heat Loss Mechanisms
Example: sweating, skin vasodilation, dec. heat production
What is the role of fat and skin in terms of regulation of body temperature?
Fat:
Skin:
Fat: INSULATOR
Skin: Radiator system (when cold: blood vessel constriction; when hot: blood vessel dilate)
Most of the body heat is lost through which way?
Radiation > Evaporation > Conduction of air > Conduction of object
Pathophysiology of Fever?
Pyrogens -> Inc IL-1 (alpha and beta), IL-6 -> inc prostaglandin -> inc set-point temp in Hypothalamus
Heat Exhaustion vs Heat Stroke
Heat Exhaustion: inc sweating causing fainting
Heatstroke: inc body temp causing tissue damage and impaired response
Hight temp secondary to the use of Succinylcholine & Halothane?
Malignant Hyperthermia
What is the basis for muscle endurance?
Glycogen levels in the body
What is the diet for muscle glycogen recovery?
High Carbohydrate Diet
How long does it take to recover muscle glycogen?
2 days ( High Carbohydrate Diet)
An increase in muscle strength is always due to what?
Inc. in muscle size
In respiratory system in exercise, maximal breathing capacity
150-170L/min
In respiratory system in exercise, pulmonary ventilation during maximal exercise
100-110L/min
Sweat glands may acclimatize to hot and humid conditions because of
Aldosterone
Inconsistence result on effects on athletic performance
Caffeine
Increase muscle strength and aggresiveness and may also cause MI, and stroke due to HPN, inc LDL and dec HDL, and testicular atrophy
Testosterone
Psychological effects only; may cause VFib
Amphetamine
Cocaine
What are the changes seen in Natural Acclimatization?
- dec body mass, inc chest size
- larger heart and lungs
- better O2 delivery ( inc Hgb, better O2 utilization)
What are the manifestations of acute mountain sickness?
- Acute Pulmonary Edema
2. Acute Cerebral Edema
What are the manifestation in Chronic mountain sickness?
- Pulmonary Vasoconstriction
2. Right sided heart failure
High nitrogen pressure cause Joviality
120 feet
High nitrogen pressure cause Drowsiness
200 - 250 feet
High nitrogen pressure cause “rapture of the depths” and alters ionic conductance in brain cells and inc nitrogen.
Beyond 250 feet
High O2 pressure, breathing O2 at 4atm(PO2= 3040mmHg) will cause sudden brain seizures followed by coma du to
O2 Free Radicals ( O2 and H2O2)
High Carbon Dioxide Pressure occurs when:
- Diving apparatus has malfunction
2. Severe respiratory acidosis, lethargy and narcosis
Formation of nitrogen bubbles
Decompression sickness
Manifestation of Decompression sickness (3)
- BENDS (joints and muscle pain)
- CHOKES (dyspnea)
- Caisson’s Disease ( Chronic DS)
Treatment of Decompression Sickness (3)
- US Navy Decompression Tables
- Tank decompression
- Use helium in very deep dives in less than 250 feet
