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 29628 235 49 Height of Mount Everest

Immediate /Acute effects of Hypoxia 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

Deep Sea Diving

Pressure at different levels under the sea ONE L ½ L ¼ L

Pressures after Sudden Decompression

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 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 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