Physiological Events Flashcards
Difference between classic hornet and super hornet
Super hornet = OBOGS
Classic hornet = liquid oxygen LDBO
Percentage of oxygen from OBOGS
93-95%
What are symptoms Physiology events
Hypoxia Cognitive impairment felt slow Task fixation Working hard Minor flight path deviations corrected by wingman and ATC Headache SOB Reduced exercise tolerance Cough Fatigued
Proposed Mechanisms of PE
Multi factorial
1- O2 related and acceleration atelectasis most supported current
2 - hypocapnia due to hyperventilation (due to stress)
Others
- hypoxia
- hyperoxia
- hypocapnia
- WOB
- BAS flow and resistance
- DCS
- Contammination
- thermal stress/dehydration
- Psychophysiological response
Cause atelectasis, symptoms
Can occur <60% oxygen
Pathology: physiological significant hypoventilation and shunt of pulmonary circulation, resulting in a reduction of hypoxia tolerance
Symptoms can persistent for 24 hours
Hypocapnia in aviation
Causes
- hypoxaemia
- arousal/anxiety
Alteration of respiratory cycle
Combined with environmental stress
Aircraft factors
- Altitude, speed, air density, humidity, heat load, supply pressure, OBOGS cycling, Plenum volume, regulator characteristics.
ALSE
- Pilot- interface factors
- mask seal
- fit
- restriction to flow
- constriction
- respiratory patterns - rate, volume and sensation
- individual variability
Aircrew controlled-breathing cycle
Breath in - take deliberate deep inhalation over approximately 5 seconds Hold 5 seconds Breath out over 5 Rest - 5 normal breathes Repeat - up to 5 times Cough
When should pilots conduct ACBC
Pre- G Post - G Post - flight Transit - every hour duration long transits As required PE recovery action
Initial response to PE
Initially based f clinical situation
Vitals as soon as practical
If available include Rad - 57 CO-Hb
If asymptomatic
- observe for a 20mins
- take detailed history
- Document - USN Part C, PM220, DeHS
- Aircrew sentinel report, ASOR, physiological incident form Part 1, B
If symptomatic
- Apply 100% oxygen via NRB mask for 20mins
- Clinical mx IAW ARC guidelines
- Facilitate pt transfer if required
- Avoid hyperventilation and encourage lung inflation
IX for PE
CO-Hb
Routine bloods
Toxicology screen: ethanol, urine drug screen, hydrogen cyanidee, a role in, hydrocarbons
CXR: only if indicated
Documents for PE
IAM HPAC PE form PM220
USN physiological Event part C
Document in DeHS