580 likes | 812 Views
Individual Reactions to acute Hypoxia-Symptoms of Jet Fighter Pilots and High Altitude Parachutists. Colonel ret. Dr. med. Dipl.-Ing. H. Welsch former Head (1993 – 2007) of German Institute of Aviation Medicine, - Division Aviation Physiology – Königsbrück.
E N D
Individual Reactions to acute Hypoxia-Symptoms of Jet Fighter Pilots and High Altitude Parachutists Colonel ret. Dr. med. Dipl.-Ing. H. Welsch former Head (1993 – 2007) of German Institute of Aviation Medicine, - Division Aviation Physiology – Königsbrück High Altitude: Physiology and Praxis, Slovenia Sep 2009
Source: Wissenschaftliche Prüfungsarbeit zum Ersten Staatsexamen für das Lehramt an Gymnasien Gegenüberstellende Betrachtung der subjektiven Wahrnehmung von Sauerstoffmangel-Symptomen bei Freifallspringern und Jet-Piloten “Comparison of acute Oxygen-Deficiency-Symptoms between High Altitude Parachutists and Jet Fighter Pilots” Nina Alexandra Gleber im SoSe 2008 Referenten: 1. Prof. Dr. med. H.-V. Ulmer 2. Prof. Dr. M. Macsenaere
Hypothesis and Aim of the Study • High altitude training in a low pressure chamber is a mandatory task in NATO for each military person who takes part in high altitude air traffic. • It was presumed that fast jet fighter pilots, all of them full ranked officers, might react more sensitively on hypoxia symptoms than high altitude parachutists, most of them enlisted soldiers with quite a different education in military behaviour. • The aim of the study was to compare reaction times from both groups to verify or deny the hypothesis.
Hypothesis and Aim of the Study • High altitude training in a low pressure chamber is a mandatory task in NATO for each military person who takes part in high altitude air traffic. • It was presumed that fast jet fighter pilots, all of them full ranked officers, might react more sensitively on hypoxia symptoms than high altitude parachutists, most of them enlisted soldiers with quite a different education in military behaviour. • The aim of the study was to compare reaction times from both groups to verify or deny the hypothesis.
Hypothesis and Aim of the Study • High altitude training in a low pressure chamber is a mandatory task in NATO for each military person who takes part in high altitude air traffic. • It was presumed that fast jet fighter pilots, all of them full ranked officers, might react more sensitively on hypoxia symptoms than high altitude parachutists, most of them enlisted soldiers with quite a different education in military behaviour. • The aim of the study was to compare reaction times from both groups to verify or deny the hypothesis.
Hypothesis and Aim of the Study • High altitude training in a low pressure chamber is a mandatory task in NATO for each military person who takes part in high altitude air traffic. • It was presumed that fast jet fighter pilots, all of them full ranked officers, might react more sensitively on hypoxia symptoms than high altitude parachutists, most of them enlisted soldiers with quite a different education in military behaviour. • The aim of the study was to compare reaction times from both groups to verify or deny the hypothesis.
Simulation Centre with Human Centrifuge and Altitude Chamber German Air Force Institute of Aviation Medicine - Division Aviation Physiology, D-01936 Königsbrück, Germany
German Air Force Institute of Aviation Medicine Division Aviation Physiology • Actual Training Devices and Areas: • Human Centrifuge, Altitude Chamber, Anti-G-Trainer, Spatial Disorientation Device, Night Vision Training Device, Special Physical Training Equipment, Aviation Psychology (CRM) • Actual Tasks: • Evaluation, Training, Diagnostics, Research, Development, Test facility for industry
Training Devices • Altitude Physiology • Acceleration Physiology • Sports Physiology • (Back/Neck Training!) • Nutrition Physiology • Aviation Psychology • Night Vision Training
Altitude Physiology • Acceleration Physiology • Sports Physiology • (Back/Neck Training!) • Nutrition Physiology • Aviation Psychology • Night Vision Training Altitude and Hypoxia Training
Altitude Simulation Chamber Hypo baric + Hypoxia Training
Altitude Simulation Chamber Königsbrück • Max. Pressure Alt. 82.000 ft = 25.000m • Main Chamber: • Climb-/Descend-Rate: • +/- 20.000 ft/min • Temperature: • +15 - +50 0C • Decompression-chamber • Climb-/ Descend-Rate: +/- 50.000 ft/min • Temperature: • -50 - +10 0C • RD: minimal 300 ms
oxygen regulator with remote control Switch „100% Oxygen“
Pulsoxymeter ECG-Monitor Multi-channel- Monitor
Pulsoxymeter Multi-channel- Monitor
Oxygen Saturation Curve physiological zone incomplete compensation zone deadly zone
Altitude Atmospheric pO² (ft) (km) pressure (hPa) (hPa) 0 0 1013 213 3.000 0,914 908 191 7.000 2,134 782 164 10.000 3,048 697 146 12.000 3,658 645 135 15.000 4,572 572 120 18.000 5,486 506 106 20.000 6,096 466 98 22.000 6,706 428 90 25.0007,620377 79 30.000 9,144 302 63 36.000 10,973 228 48 40.000 12,192 188 40
Objective of Training (1) • Barometric Changes • ear drum, sinuses, trapped gases • Pressure Breathing (>28.000 ft) • hyperventilation, breathing workload • Acute Hypoxia (25.000 ft) • individual symptoms (at least 2!) • Hypoxia in max.operational cabin altitude (18.000 ft): only jet fighter pilots
Objective of Training (2) • Altitude Hypoxia Exposure • primarily no diagnostic/evaluation tool! • situational awareness training: • flying in high altitude • instrumental cross check including oxygen equipment; “PRICE”-check • Oxygen Equipment Safety Training • Confidence Training
Signs and Symptoms of Hypoxia • Because there is always a risk of equipment failure at high altitude, early recognition of hypoxic symptoms is mandatory. • The constellation of hypoxic symptoms and their sequence of appearance tend to be idiosyncratic to the individual. • As a rule, the individual‘s symptoms do not change dramatically over time, but refresher training in a chamber does reacquaint the individual with the symptoms, as well as identify any change in symptoms.
Signs and Symptoms of Hypoxia • Because there is always a risk of equipment failure at high altitude, early recognition of hypoxic symptoms is mandatory. • The constellation of hypoxic symptoms and their sequence of appearance tend to be idiosyncratic to the individual. • As a rule, the individual‘s symptoms do not change dramatically over time, but refresher training in a chamber does reacquaint the individual with the symptoms, as well as identify any change in symptoms.
Signs and Symptoms of Hypoxia • Because there is always a risk of equipment failure at high altitude, early recognition of hypoxic symptoms is mandatory. • The constellation of hypoxic symptoms and their sequence of appearance tend to be idiosyncratic to the individual. • As a rule, the individual‘s symptoms do not change dramatically over time, but refresher training in a chamber does reacquaint the individual with the symptoms, as well as identify any change in symptoms.
Pilots and Parachutists • Aircrew (Pilots and WSO): • above 8.000 ft pressure altitude in the cockpit: additional oxygen in the breathing gas is required. Jet fighter aircraft aircrew is always equipped with oxygen breathing mask. • High altitude parachutists: • HAHO: High Altitude, High Opening: • Pre-breathing in the A/C, oxygen breathing in the air • HALO: High Altitude, Low Opening • Pre-breathing in the A/C, normal breathing in the air
Altitude-Time-Profile Jet Fighter Pilots Altitude (ft) III Hypoxia training: pressure altitude 25.000 ft 35 000 30 000 10 000 ft/min IV 25 000 4 000 ft/min V 4 000 ft/min 20 000 18 000 15 000 2 000 ft/min II 10 000 8 000 4 000 ft/min 5 000 VI 3 000 I Time (min.) 20 30 40 50 60 70 80 90 10
Pilots and Parachutists • Aircrew (Pilots and WSO): • above 8.000 ft pressure altitude in the cockpit: additional oxygen in the breathing gas required. Jet fighter aircraft aircrew is always equipped with oxygen breathing mask. • High altitude parachutists: • HAHO: High Altitude, High Opening: • Pre-breathing in the A/C, oxygen breathing in the air • HALO: High Altitude, Low Opening • Pre-breathing in the A/C, normal breathing in the air
Altitude-Time-Profile for High Altitude Parachutists Hypoxia training: pressure altitude 25.000 ft III 35000 10000 ft/min 30000 IV 25000 Höhe (ft) 10000 ft/min 20000 4000 ft/min V 15000 II 2000 ft/min 10000 2000 ft/min 5000 VI 4000 ft/min I 30 40 50 60 70 80 10 20 Zeit (min)
Monitoring Oxygen saturation % 100% 90% 75% 60% Heart rate Breathing 21% oxygen 25.000 ft 18.000 ft
Early (covert) features (signs and symptoms) of acute hypoxia* • Visual function: • Light intensity perceived as reduced • Visual acuity diminished in poor illumination • Light threshold increased • Peripheral vision narrowed • Psychomotor function: • Choice reaction time impaired • Eye-hand co-ordination impaired • Cognitive function: • Memory impaired
Overt features (signs and symptoms) of acute hypoxia* • Personality Change: • Lack of insight • Loss of judgement • Loss of self-criticism • Euphoria • Loss of memory • Mental incoordination • Muscular incoordination • Sensory loss • Cyanosis • Hyperventilation: • Dizziness • Light-headedness • Feeling of unreality • Feeling of apprehension • Neuromuscular irritability • Paraesthesia of skin • Unconsciousness • Death
Results: Pressure Altitude 25.000 ftQuestions and Answers Statistic Data of Trainees First Hypoxia Symptoms (Time and SaO2) Duration of Breathing 21% Oxygen until Re-connection to 100% Oxygen Breathing Gas (Time and SaO2) Time between first Hypoxia Symptom and Re-connection to 100% Oxygen
Results Pressure Altitude 25.000 ft Statistic Data of Trainees First Hypoxia Symptoms (Time and SaO2) Duration of Breathing 21% Oxygen until Re-connection to 100% Oxygen Breathing Gas (Time and SaO2) Time between first Hypoxia Symptom and Re-connection to 100% Oxygen
Results Pressure Altitude 25.000 ft Statistic Data of Trainees First Hypoxia Symptoms (Time and SaO2) Duration of Breathing 21% Oxygen until Re-connection to 100% Oxygen Breathing Gas (Time and SaO2) Time between first Hypoxia Symptom and Re-connection to 100% Oxygen
Results Pressure Altitude 25.000 ft Statistic Data of Trainees First Hypoxia Symptoms (Time and SaO2) Duration of Breathing 21% Oxygen until Re-connection to 100% Oxygen Breathing Gas (Time and SaO2) Time between first Hypoxia Symptom and Re-connection to 100% Oxygen
Oxygen Saturation when re-connected to 100% Oxygen breathing gas 120 100 80 60 Number of Trainees Pilots Parachutists 40 20 0 99% 95% 90% 85% 80% 75% 70% 65% 60% Oxygen Saturation (%)
SaO2: Re-Connection to 100% Oxygen Breathing Gas Most of these trainees are forced by the instructor to re-connect themselves to 100% oxygen breathing gas, when reached the 70% SaO2-level. The „after-drop“ explains the values between 60 – 70% SaO2.
Oxygen Saturation whenre-connected to 100% Oxygen • 207 (78%) of 265pilots are re-connected before their oxygen-saturation dropped beneath 70%. • Only 146 (60%) of 244parachutists are re-connected before their oxygen-saturation dropped beneath 70%.
Results Pressure Altitude 25.000 ft Statistic Data of Trainees First Hypoxia Symptoms (Time and SaO2) Duration of Breathing 21% Oxygen until Re-connection to 100% Oxygen Breathing Gas (Time and SaO2) Time between first Hypoxia Symptom and Re-connection to 100% Oxygen
Time between First Symptom and Re-Connection to 100% Oxygen Breathing Gas 72% 62%
265 Pilots 250 Parachutists
Duration of Hypoxia between first Symptom and Re-Connection to 100% Oxygen • 229 (91%) of 253pilots are re-connected within the first minute (60 seconds) after recognition of their first hypoxia-symptom. • Only 168 (70%) of 241parachutists are re-connected within the first minute (60 seconds) after recognition of their first hypoxia-symptom.
Results – Smoker/Non-Smoker MORE OR LESS: NO DIFFERENCE!