Dive Physiology And Medical Aspects Underwater Physiology Respiration

Dive Physiology And Medical Aspects

Underwater Physiology Respiration Effects of heat and cold Barotrauma Pressure related problems – Direct – Indirect

Respiration The breathing cycle Oxygen consumption Carbon dioxide Breath holding Hypoxia hypercapnia/hypocapnia Carbon monoxide poisoning

Respiration The Process Movement of air into and out of the lungs Transport of oxygen to the cells and removal of carbon dioxide Aorta Mouth, Nose, Throat Pulmonary Artery O 2 CO 2 Lungs Bronchioles Trachea CO 2 Bronchi Alveoli Lungs Capillaries O 2 Pulmonary Vein Heart Vena Cava Diaphragm Air Must Pass Through “Dead” Spaces Hemoglobin Molecules in Red Blood Cells Carry Oxygen Approx. 5% Oxygen Consumed Carbon Dioxide Increases 5% Shallow Water Blackout Caused by Excessive Hyperventilation Skip Breathing Causes Hypercapnia Air with Less Than 10% O 2 at 1 atma Will Not Support Consciousness

Effects of Heat and Cold Heat injuries (hyperthermia) – cramps – exhaustion – stroke Cold injuries (hypothermia) – Decreased body functions – Decreased mental functions – Shivering, numbness – Related protection requirements

Temperature Injuries Progressive Symptoms and Effects Heat t. A id Cool Victim Oral Fluids No Caffeine/Alcohol t. A id Uncontrolled Shivering Loss of Coord/Dexterity Numbness 1 s mp tom s - Hypothermia Sy Profuse Sweating Weakness Malaise Dry, Flushed Skin 1 s Sy mp tom s - Cramps - Exhaustion - Stroke Cold Warm Victim No Caffeine No Alcohol

Pressure Related Problems (direct) Descent (squeezes) – – – – Ears Sinuses Mask Thoracic Teeth Stomach/Intestines Suit Ascent (expansion) – Air embolism – Pneumothorax – Mediastinal Emphysema – Subcutaneous Emphysema

Pressure Related Problems (indirect) Decompression sickness – Nitrogen partial pressures – Solubility Nitrogen narcosis Oxygen toxicity

Nitrogen narcosis Nitrogen Narcosis “Rapture of the Deep” - “Martini’s Law” SURFACE Thinking and Judgment POTENTIALLY Affected 75 -100’ Communication, Motor and Mental Tasks IMPAIRED Symptoms and Effects on Individual Diver Vary With Depth and Exposure. 150 -175’ NOT IN CONTROL 200’+

Barotrauma Direct Pressure Related Problems Indirect Pressure Related Problems - Descent (Compression) Squeezes - Decompression Sickness (The Bends) (DCS) Ear, Sinus, Lung, Stomach, Intestinal, Tooth, Equipment - Nitrogen Narcosis Descend and Ascend Slowly to Minimize Potential Problems - Oxygen Toxicity - Ascent (Expansion) Lung Ruptures Subcutaneous and Mediastinal Emphysema Pneumothorax Air Embolism NEVER HOLD YOUR BREATH ON SCUBA! Precautionary Decompression Stops (Safety Stops) Help Reduce Bubble Formation and Incidence of DCS

Physiology Summary Respiration is Mechanical - Oxygen-Carbon Dioxide Exchange - Slow Deep Breathing Proper Exposure Protection is Required to Avoid Hypothermia Barotrauma - Pressure Injury - Direct Subcutaneous Emphysema Mediastinal Emphysema Pneumothorax Air Embolism - Indirect DCS (the Bends) Nitrogen Narcosis Oxygen Toxicity