Anatomy and Physiology Practice

• Change to the recommended CPR sequence prioritizes chest compressions before rescue breaths (C-A-B instead of A-B-C).
• The lone rescuer should start CPR with 30 compressions to minimize delays.
• Compression rate should be at least 100/min.
• Compression depth for adults should be at least 2 inches (5 cm).

A Change from A-B-C to C-A-B

• Bystander CPR is low.
• The A-B-C sequence may be a factor because rescuers struggle with airway and breathing steps.
• Hands-Only CPR (compressions-only) emphasizing "push hard and fast" should be used by untrained bystanders for adults who collapse.
• Trained rescuers should provide chest compressions and breaths at a 30:2 ratio until medical care arrives.

Hands-Only CPR

• Hands-Only CPR is easier for untrained rescuers to perform with guidance.
• Survival rates from cardiac arrests are similar with Hands-Only CPR or CPR with compressions and rescue breaths.
• Trained rescuers should ideally perform both compressions and ventilations.

BODY STRUCTURE AND FUNCTIONS

• Anatomy refers to the study of the body and its parts.
• Physiology is how the body functions.
• Cells are the building blocks of the human body.
• Most cells contain cytoplasm and a nucleus; red blood cells lack a nucleus.
• Genetic material resides in the nucleus.
• Cytoplasm is mostly water.
• Tissues are formed by cells of the same type (e.g., muscle or nerve tissue).
• Organs are structures made of two or more tissues for a common purpose and systems composed of organs.
• Skin is the largest organ, containing epidermis, dermis, and subcutaneous layers.
• Bones form the body's framework is.
• Muscles enable bone movement is
• Skin covers the body is
• Bones, cavities and muscles, protect soft organs.

Regional Parts of the Human Body

• Head and neck (skull, brain, cervical spine)
• Upper limb (hand, wrist, forearm, elbow, arm, shoulder)
• Thorax (rib cage, thoracic spine, lungs, heart, diaphragm, major vessels)
• Abdomen (stomach, intestines, liver, pancreas, gall bladder)
• Spine (vertebrae, sacrum, coccyx, inter-vertebral disc, spinal cord)
• Pelvis (pelvic bones, uro-genital organs, part of intestines)
• Lower limb (hip joint, thigh, knee, leg, ankle, feet)

Chest Cavity (Thoracic Cavity)

• Breastbone in front, 12 pairs of ribs on sides, 12 thoracic vertebrae behind, and diaphragm below.
• Contains lungs, heart, food pipe, and wind pipe.

The Heart as a Pump

• The heart's contractions are controlled by a pacemaker within it.
• Normal heart rate is 60-90/min, averaging 72/min; it varies with activity and emotion.
• The heart beats about 2.5 billion times in an average 70-year lifespan.
• The Systemic circuit: left atrium to left ventricle, then to body through the aorta.
• Deoxygenated blood returns to the right atrium, which pumps to the right ventricle.
• The Pulmonary circuit: right ventricle to lungs via the pulmonary artery, then to the left atrium via the pulmonary vein.

Arteries

• Strongest, elastic blood vessels withstand high pressure and carry blood away from the heart.
• All arteries carry oxygenated blood except the pulmonary artery.
• Arteries have three layers: outer, middle, and inner.
• Arteries are deep-seated.
• Expansion and return to normal is the pulse.
• Arteries divide into smaller vessels called capillaries.

Pressure Points

• Pressure points are where pulses can be felt.
• Located at joints where arteries are superficial and lie on bone.
• Pressure can be applied to these points to stop blood flow.

Accessory Digestive Organs

• Liver and pancreas secrete bile and pancreatic juice/insulin/glucagon.
• These secretions are very important for digestion.
• Tongue: muscle for taste, speech and, swallowing.

Stomach

• A muscular pouch about 16" long.
• Churns and mixes food with hydrochloric acid and enzymes.

Liver

• Largest gland, 1/40th of body weight.
• Dark red, dome-shaped, under the diaphragm on the right side, protected by ribs and abdominal muscles.
• Weight: Males 1.4-1.6 kg; Females 1.2-1.4 kgs. Divided into right and left lobes.
• Made of tiny cells arranged in cords, one cell thick.
• Known as the master laboratory of the body.

Functions of the Liver

• Regulates blood chemical levels and secretes bile.
• Bile helps break down fats for digestion and absorption.
• All blood from the stomach and intestines passes through the liver.
• Processes blood, breaking down nutrients and drugs.
• Performs over 500 vital functions Some functions include:
  • Producing bile for waste removal and fat breakdown.
  • Producing proteins for blood plasma.
  • Producing cholesterol and special proteins for fat transport.
  • Converts excess glucose into glycogen for storage.
  • Converts amino acids into albumin
  • Regulates blood clotting.
  • Removes toxins from food, medicines, viruses, and bacteria.
  • Produces immune factors and removes bacteria from the bloodstream.
• Appendix: A vestigial organ with no known function in humans.

Acute Appendicitis

• Inflammation of the appendix; often requires surgical removal.
• A common cause of severe acute abdominal pain.
• Untreated, carries a high risk of death due to rupture, peritonitis, and shock.

The Urinary (Excretory) System

• Consists of:
  • Two kidneys
  • Two ureters
  • One urinary bladder
  • One urethra

Kidneys

• Located in the abdomen, on either side of the spine, approximately at the level of the lowest ribs
• The right kidney is lower than the left kidney.
• Bean-shaped and brown.
• Composed of millions of filters called nephrons.
• Allow waste and excess water into the ureter at 1-2 liters/day.

Ureters

• Act like drainpipes, pushing water to the bladder.
• Use wave-like contraction movements.

Urinary Bladder

• Storage tank that is small, bag-like, and triangular.
• The base has openings for the ureters.
• The apex has an opening for the urethra.
• Urine exits through the external urethral meatus.
• Capacity is about 400-600ml.

Amputation

• Causes: Severing of part of limb; Back-lashing of wires and ropes; machinery; crush with heavy object like a banging door.
• Can be a clean cut or crush amputation.
• Symptoms: Part of body missing; Bleeding and/or severe pain in 50% of cases; Shock is always seen.
• Treatment: Treat shock; Apply Tourniquet if bleeding; Pain killers.
• Preserve amputated part in polythene bag. Place this bag in ice. Store at 2-4 degrees C. Stitch back if possible.

Crush Injury

• Cause: Heavy object falling on part of the body; Banging of heavy door or cargo or machinery on hand/foot/body.
• Symptoms: Bleeding and/or severe pain in 50% of cases; Shock is always seen; Can lead to a "frozen limb".
• Treatment: Treat shock; Stop bleeding; Painkillers; Splint and Bandage in the "functional position".

'Sucking' Chest Wound

• Cause: Open wound on chest; Stab on chest
• Symptom: Can hear a sucking sound of air at the site of injury; Can lead to collapse of lung and death.
• Treatment: Immediately seal the wound with a cloth and then make a 3 way airtight seal; Give 100% Oxygen; Needs evacuation.

BLEEDING Types

• Arterial: bright red blood, pulsatile bleed against gravity.
• Venous: dark red, continuous stream of blood with gravity.
• Capillary: oozes out slowly.