Stresses of Transport Hypoxia Trapped Air Thermal changes Decreased Humidity Noise Vibration Fatigue Gravitational, acceleration/deceleration forces

Hypoxia An oxygen deficiency sufficient to cause an impairment of function Causes –Inadequate supply of oxygen –Inadequate oxygen transport capability –Inability of body to use oxygen

Stages of Hypoxia Indifferent Stage –Physiologic zone: 0 – 10 K feet –Increased HR and RR –Decrease in night around 5 K

Stages of Hypoxia Compensatory Stage –10 K – 15 K feet –Increased HR, RR, BP, Respiration Depth –Drowsiness –Poor judgement –Impaired coordination –Impaired efficiency

Stages of Hypoxia Disturbance Stage –15 K – 20 K feet –Characterized by Dizziness, sleepiness, tunnel vision, cyanosis, slowed thinking and decreased muscle coordination. –Which can cause… Impaired flight control Impaired handwriting Impaired speech Decreased coordination

Stages of Hypoxia Critical Stage –20 K - 30 K feet –Mental confusion and incapacitation –Unconsciousness –Circulatory failure –Cardiovascular collapse –Death

Types of Hypoxia Hypoxic Hypoxia Anemic Hypoxia Stagnant Hypoxia Histotoxic Hypoxia

Hypoxic Hypoxia Deficiency in alveolar oxygen exchange. Causes –Reduction of pO 2 in inspired air –Ineffective gas exchange in an area of the lung Result –Inadequate oxygen supply in arterial blood

Hypoxic Hypoxia Altitude Pressure Oxygen sea level 760mmHg 160mmHg 1000 ft ft ft ft Reference Protocol: –Atmospheric Pressure, Limits for Specific Disease Processes

Hypoxic Hypoxia Treatment –Supplemental 02 –Altitude restriction –BIPAP –Advanced airway management –Fix problem

Anemic Hypoxia Reduction of 02 carrying capacity –Decrease in circulating Hgb –Reduction of functional / avail Hgb Treatment –Maximize available 02 –Consider transfusion

Stagnant Hypoxia 02 deficiency secondary to poor circulation –Heart failure –Hypovolemia –Shock (any source) Treatment –Maximize 02 supply –Maximize 02 delivery Consider volume Consider pump

Histotoxic Hypoxia Inability to utilize 02 at cellular level –“Poisoned tissue” Causes –Sepsis –Alcohol –Cyanide –Carbon monoxide Treatment –Cause specific