Transport Physiology Flashcards
Boyle’s Law
At a constant temperature, a volume of gas is inversely proportional to pressure. Example: The volume of pneumothorax will increase as altitude increases due to the decrease in barometric pressure.
Dalton’s Law
Relates to pressure of a mixture of gases. Gases in a mixture exert pressure equivalent to the pressure each would exert if present alone in the volume of a total mixture. Example: a tank with 1900psi with a mixture of 20% O2 and 80% nitrogen, has pressure exerted inside of it where the O2 exerts 20% of the pressure and the nitrogen exerts 80% of the pressure.
Charles’ Law
When pressure is constant, volume of a gas very nearly proportional to its absolute temperature. Example: TV of air at room temperature increases in size inside the body as it reaches body temperature.
Gay-Lussac’s Law
Pressure of a gas when volume is maintained constant is directly proportional to the absolute temperature for a constant amount of gas. Example: pressure in an oxygen tank decreases as the temperature decreases.
Henry’s Law
Solubility of gases in liquids and states. The quantity of gas dissolved in 1cm3 (1 ml) of a liquid is proportional to the partial pressure of the gas in contact with the liquid. Example: decompression sickness - diver that ascends too rapidly nitrogen bubbles form in the blood.
Graham’s Law
Rate of diffusion of a gas through a liquid is directly related to the solubility of the gas, inversely proportional to the square root of its density or gram molecular rate. Example: gas exchange at the cellular level.
Night loss vision occurs at….
5000 ft
Hypoxia: Indifferent stage
Sea level to 10,000 ft. Body will increase HR, ventilation slightly
Hypoxia: Compensatory stage
10,000-15,000 ft. Increase in BP, HR, depth/rate of ventilation occurs.
Hypoxia: Disturbance stage
15,000-20,000 ft. Dizziness, sleepiness, tunnel vision, cyanosis.
Hypoxia: Critical stage
20,000-30,000 ft. Mental confusion, incapacitation, followed by LOC within minutes.
Hypoxic Hypoxia
Deficiency in alveolar exchange. Decreased barometric pressure at high altitudes causes a reduction in alveolar partial pressure of oxygen (PaO2). O2 sat at sea level 98% —> 87% at 10,000’ —> 60% at 20,000’.
Hypemic Hypoxia
Reduction in oxygen carrying capacity of blood. # of RBC’s reduced per unit volume of blood, oxygen-carrying capacity thus oxygen content of blood is reduced. Anemia, blood loss, carbon monoxide, etc…
Stagnant Hypoxia
Condition that exists w/ reduction in total CO. Heart failure, shock, PE.
Histotoxic Hypoxia
Tissue poisoning that results in a cell’s inability to use molecular oxygen. Carbon monoxide, cyanide, ETOH…
Decompression Sickness
Supersaturation of the tissues w/ Nitrogen. Gives rise to the formation of bubbles. Henry’s law. Primary treatment is recompression to ground level, 100% O2
Revised Trauma Score 4
GCS 13-15
SBP>89
RR 10-29
Revised Trauma Score 3
GCS 9-12
SBP 76-89
RR >29
Revised Trauma Score 2
GCS 6-8
SBP 50-75
RR 6-9
Revised Trauma Score 1
GCS 4-5
SBP 1-49
RR 1-5
Revised Trauma Score 0
GCS 3
SBP 0
RR 0
Rhabdomyolysis
Increased CK, K, BUN, Creat, phos, uric acid, AST, ALT. Low pH, metabolic acidosis.
Decrease ICP
HOB 30*, neutral alignment, ? remove c-collar
Hypokalmeia - EKG
Flattened T, prominent U wave
Hyperkalemia - EKG
Peaked T
When should MIVF’s be changed to a dextrose source in a DKA PT?
Serum BG reaches 200-250mg/dL
SVR - low or high in distributive shock
Low - seen in neurogenic, septic, anaphylactic. Normal 800-1200 dynes/sec. Afterload low d/T massive vasodilation.
Calculate P:F ratio. What is normal?
<200 mmHg indicates ARDS. 201-300 indicates acute lung injury. >400 ideal.
PaO2 divided by FiO2 (expressed as a decimal).
What parameter increases in early shock?
Increased DBP d/T the initial vasoconstriction. Pulse pressure narrows d/T the increase in DBP and decrease in SBP.
Describe early shock
Tachycardia, widened pulse pressure, increased CO, decreased BP.
Describe late (cold/hypodynamic) shock
Decreased CO, decreased BP
In what order do the phases of distributive shock from sepsis occur?
Hyperdynamic (warm), hypodynamic (cold), normodynamic (following adequate fluid resuscitation), and vasodynamic (referring to hemodynamic parameters such as CO)
Which law explains why a rotor wing aircraft may be able to lift off with a heavier patient in cold weather?
Charles’s Law. Cold, dense air contract as temperature decreases. Contracting of gases illustrates decreasing volume which can produce a greater lift.
How should a laboring PT be prepared for transport?
Place PT’s w/ >4cm dilation in a side-lying trendelenburg position w/ safety belts below the uterus, pillow under hips for pelvic tilt
Initial management of pancreatitis…
Adequate fluid resuscitation
Which of the following electrolytes is more often affected w/ PT w/ acute pancreatitis?
Hypocalcemia d/T fluid loss. Cardiac and neurological impact can be severe.
Gay-Lussac’s Law
As altitude increases, pressure and temperature decrease.
Reduction in oxygen carrying capacity of blood:
Hypemic hypoxia
Zone considered most acceptable to PT transport R/T normal physiological functioning?
Efficient zone
Time of useful consciousness at X feet…when rapid decompression occurs
18,000 - 30 minutes
25,000 - 3-5
30,000 - 90 seconds
35,000 - 30-60
40,000 - 15 or less
Medication class prolonged by presence of liver disease
Benzodiazepines
System most affected by compensatory mechanisms and hypoxia R/T shock
Integumentary, neurological, urinary/excretory
An infection exposure that may require chemo prophylaxis
Neisseria meningitides
