ALTITUDE HIGH & DEEP SEA DIVING
High Altitude Physiology • Altitude Barometric Pres PO2 Effects • 5000 feet 600 mmHg 132 No hypoxia • 10000 523 mmHg 110 Mild symptoms of hypoxia • 15000 400 mmHg 90 Moderate hypoxia • 20000 349 73 severe hypoxia Highest level for permanent inhabitants • 29628235 49 Height of Mount Everest
Immediate /Acute effects ofHypoxia • In unacclimitized Person at 10-12000 feet 1. Drowsiness 2. Lassitude 3. Muscle fatigue 4. Nausea 5. Headache 6. Mental proficiency > Judgment , memory and motor activity > Twitching & Seizures at 18-20,000 feet > Coma & death above 23000 feet
Mountain Sickness • Is the condition characterized by adverse effects of hypoxia at high altitude. • Acute mountain sickness • Chronic mountain sickness
Symptoms of Mountain Sickness • GIT. Mostly due to expansion of gases: Painful distention of stomach and intestine Loss of Appetite Nausea, vomiting Respiratory system: Breathlessness- Pulmonary edema Pulmonary edema due to Hypoxia
Nervous System: • Headache • Depression • Disorientation, Irritability, • weakness & fatigue- - All CNS symptoms develops due to CEREBRAL EDEMA
Acclimatization • “ Adaptation or Readjustments in the body to high altitude “ -
Changes during Acclimatization: • Changes in blood RBC count increases Packed cell volume increases Hemoglobin content increases. • Changes in CVS Rate and force of contraction of heart increases Cardiac output increases Vascularity increases.
Changes in Respiratory system Pulmonary ventilation increases Pulmonary hypertension. Diffusing capacity of gases increases. • Changes in tissues Amount of oxidative enzymes increases Increase in number of mitochondria
Chronic mountain sickness • Red cell mass and hematocrit increases exceptionally high. • Pulmonary arterial pressure becomes elevated. • Right side of the heart enlarges. • Peripheral arterial pressure falls • Congestive heart failure • Death
Pressure at different levels under the sea ONE L ½ L ¼ L
Decompression Sickness,Caisson’s Disease, Dysbarisom • Occurs when a person returns rapidly to sea level after exposure to High Atmospheric Pressure.
Mechanism: after every 33 feet Pressure rises by ONE atmosphere. So high barometric pressure causes compression of gases. O2 is Utilized & CO2 is Expired out BUT N2 is an Inert Gas & highly fat soluble Bubbles out when suddenly decompressed
Symptoms of Decompression Sickness • Are mainly due to escape of N2 in the form of bubbles: • Severe pain in the tissues particularly in the Joints. • Numbness, tingling or Pricking ( paresthesia) & Itching due to bubbles in myelin sheath. • Temporary Paralysis due to bubbles in Motor Nerves • Muscle Cramps • Bubble in the blood may lead to occlusion of any vessel Nitrogen Norcosis; N2 has no effects at sea level BUT In deep sea (high Pressure), Norcotic effects starts appearing.
Prevention and Treatment Prevention • Slow Ascent with short stay at regular Intervals. Treatment • Affected person should be recompressed & then should be brought back to the sea level gradually. • Hyperbaric oxygen therapy SCUBA ( Self Contained Underwater Breathing Apparatus) Is used by deep sea divers