Altitude Sickness Flashcards
Above __ ft is when sig hypoxia occurs (Sats <90%)
1200ft
The__________
of oxygen stays the same in our atmosphere but the ____________is what changes
- percentage
2. partial pressure
Above _______ ft is considered the death zone as prolonged stay here results in hypoxia induced tissue
death.
22000
Acclimatization:
Step 1
First the ___________ detect hypoxia so it influences the medullary center to increase the respiratory
drive and increase your minute volume.
carotid body
Acclimatization: Step 2 Then you will have a \_\_\_\_\_\_\_\_\_\_ which will turn the medullary center on to \_\_\_\_\_\_\_\_\_ the respiratory drive. This happens after \_\_\_\_ days
- . Respiratory alkalosis
- decrease
- 1.5 days
Acclimatization:
Step 3
Now is when the ______ kick in and __________ to compensate for respiratory alkalosis ,
- kidneys
2. excrete bicarbonate
Acclimatization:
Step 4
Now
you can _______your ___ rate again .
increase RR rate
Acclimatization:
Step 5
Additionally, there is ___________ release with VC triggering suppression of ____ and ______ this
will result in a _______.
- catecholamine
- Aldosterone/ADH
- Diuresis
Acclimatization:
Step 5
You ________ the total number of rbc via _____ but this is late change and can take up to ___ days.
1 increase
- EPO
- 90
Acclimatization:
Enhancers (2)
Caffeine
Chocolate
Acclimatization:
Inhibitors (2)
ALCOHOL
sedatives
Acute Mountain Sickness prophylaxis
Acetazolamide
SxS Acute Mtn Sickness
Typically within __ hrs
n/v malaise and headache associated with hypoxia
48hrs
Is acute mtn sickness typically self-limited resolution of sx?
Yes
Can moderate cases of Acute mtn sickneesss stay at elevation?
When should they descend?
yes
High Lake Louise Score
What can happen if severe cases of acute mtn sickness dont descend?
HACE or HAPE
Descending ___m can be helpful w/ Acute mtn sickness symptoms?
500m
Syndromes of altitude range from ___ to ___
HAH to HACE
__ is the end stage process of acute mountain sickness: where there is vasodilation of capillary beds
then over perfusion
HACE
HACE is results in _____ (loss of autoregulation of capillary beds) that eventually leads to ____
Vasogenic edema
Cell death
HACE
Early manifestations:
Late Manifestations:
Early on manifested by headache, ataxia.
Later by altered mentation, lethargy, seizures, death
Standard Tx of HACE
DESCEND!
O2, Acetazolaminde, dexamethazone, hyperbaric chamber
If you cannot descend with HACE, second line (non rx)
portable hypobaric chamber
Do oxygen, dexamethasone and acetazolamide prevent death in HACE?
No, they just delay it. NEED TO DESCEND
__ is pulmonary edema not due to HF, but is ____ induced vasoconstriction.
HAPE
Hypoxia
HAPE: periphery _____ and sum total. there is _____ of particular tissues causes capillary leak & _____.
- Vasodilates
- overperfusion
- edema
HAPE can start at _____ft
8000ft
HAPE SxS
Cough
then dyspnea at rest
then crackles
then tachypnea
Mild cases of HAPE can be treated with ___?
O2 and Nifedipine
Moderate & severe cases of HAPE tx?
Descend
HAPE pts with crackles regardless of O2 status Tx
Descend
Takes __ days to acclimatize maximally
7
Normal Physiologic Responses to Acclimatization
What happens to RAAS?
Suppressed
due to the bicarbonate diuresis and suppression of aldosterone.
Normal Physiologic Responses to Acclimatization:
Vessels
Peripheral VC triggers baroreceptors (carotid sinus) to suppress secretion of ADH and aldosterone resulting in diuresis
Normal Physiologic Responses to Acclimatization:
Lungs
Lung: Increase in Pulmonary vascular resistance
Pulmonary vessels constriction due to hypoxemia
Respiratory Rate Increased ventilation @ 4921 ft
There is an increase of oxygen delivery to the tissues
O2 dissociation curve in response to acclimatization?
Shift to right- offload O2 to tissues easier.
How does caffeine, cocoa, GC’s and Acetazolamine help you acclimatize?
Forced bicarbonate diuresis
Does age/gender play a difference in altitude sickness?
No
Lake Louise score 2-4
Mild
stop ascent
acetazolamide 125or 250mg bid
Lake Louise Score
5-9
moderate
descend
O2
Lake Louise Score
10-15
severe
O2
Acetazolamide 250 mg and dexamethasone 10mg
immediate descent
Pressure Bag (Gamow Bag)
T/F: pts w/HACE can have weakness to a point of not being able to move
can have personality changes
True
HAH Tx?
Stop ascent acclimatize
Acetazolamide 125 or 250mg bid
Or descend 500m
T/F: HAPE pts can start to deteriorate over hours?
true.
Bottom line HAPE tx?
DESCEND