Chapter 5 The Human Body National EMS Education

Chapter 5 The Human Body

National EMS Education Standard Competencies (1 of 2) Anatomy and Physiology Uses simple knowledge of the anatomy and function of the upper airway, heart, vessels, blood, lungs, skin, muscles, and bones as the foundation of emergency care.

National EMS Education Standard Competencies (2 of 2) Life Span Development Uses simple knowledge of age-related differences to assess and care for patients.

Introduction • You must understand the basic structure and functions of the human body. • This knowledge will help you: – Understand the problem the patient is experiencing. – Perform an adequate patient examination. – Communicate your findings to others. – Provide appropriate emergency treatment.

Topographic Anatomy (1 of 3)

Topographic Anatomy (2 of 3) • The standard anatomic position is a person standing and facing you, with arms at the sides and thumbs pointing outward. – Anterior is the front surface of the body. – Posterior is the back surface of the body. – The midline refers to an imaginary vertical line drawn from head to toe that separates the body into a left half and a right half.

Topographic Anatomy (3 of 3) • Standard anatomic position (cont’d) – Medial: closer to the midline of the body – Lateral: away from the midline – Proximal: close – Distal: distant – Superior: closer to the head – Inferior: closer to the feet

The Respiratory System (1 of 6) • Brings oxygen into the body and removes the waste gas, carbon dioxide • Structures include: – Upper airway – Trachea – Lungs – Ribs – Bronchi – Diaphragm

The Respiratory System (2 of 6)

The Respiratory System (3 of 6) • The airway consists of the: – Nose (nasopharnyx) – Mouth (oropharynx) – Throat – Larynx (voicebox) – Trachea (windpipe) – Passages within the lungs

The Respiratory System (4 of 6)

The Respiratory System (5 of 6) • Oxygen and carbon dioxide are exchanged in alveoli and tissue.

The Respiratory System (6 of 6) • Air is inhaled when the diaphragm and the chest muscles contract. • Air is exhaled when these muscles relax.

The Circulatory System (1 of 8) • Includes the heart, which pumps blood through a network of blood vessels to all parts of the body

The Circulatory System (2 of 8) • Flow of blood – Blood picks up oxygen in the lungs and goes to the heart. – The heart pumps it to the rest of the body. – The cells absorb oxygen and nutrients from the blood and release waste products. – Blood carries the waste back to the lungs and kidneys. – In the lungs, the blood exchanges the carbon dioxide for more oxygen.

The Circulatory System (3 of 8)

The Circulatory System (4 of 8) • The heart consists of four chambers. – The chambers work together to pump blood to the lungs and to the rest of the body. – Each upper chamber is called an atrium. – Each lower chamber is called a ventricle. – One-way check valves allow the blood to flow in only one direction.

The Circulatory System (5 of 8)

The Circulatory System (6 of 8) • The arteries carry blood away from the heart at high pressure and, therefore, have thick walls. • There are three major arteries: – Neck (or carotid) artery – Groin (or femoral) artery – Wrist (or radial) artery

The Circulatory System (7 of 8)

The Circulatory System (8 of 8) • The capillaries are the smallest vessels. • Veins are thin-walled vessels that carry blood back to the heart. • Blood has several components: – Plasma – Red blood cells – White blood cells – Platelets

The Skeletal System (1 of 13) • The skeletal system consists of bones and is the supporting framework for the body. • It has three major functions: – To support the body – To protect vital structures – To manufacture red blood cells

The Skeletal System (2 of 13)

The Skeletal System (3 of 13) • The skull – The bones of the head include the skull and the lower jawbone. – The skull consists of many bones fused together to form a hollow sphere that contains and protects the brain. – The jawbone is a movable bone that is attached to the skull and completes the structure of the head.

The Skeletal System (4 of 13) • The spine – Consists of 33 vertebrae – The spinal vertebrae are stacked on top of one another and are held together by: • Muscles • Tendons • Disks • Ligaments

The Skeletal System (5 of 13) • The spine (cont’d) – The spinal cord passes through the hole in the center of each spinal vertebra – The spine has five sections: • Cervical spine (neck) • Thoracic spine (upper back) • Lumbar spine (lower back) • Sacrum (base of spine) • Coccyx (tailbone)

The Skeletal System (6 of 13)

The Skeletal System (7 of 13) • The shoulder girdles – Each shoulder girdle supports an arm and consists of three bones: • Collarbone (clavicle) • Shoulder blade (scapula) • Upper arm bone (humerus) • The upper extremity – The upper arm has one bone called the humerus.

The Skeletal System (8 of 13) • The upper extremity (cont’d) – The forearm has two bones called the ulna and the radius. – The wrist and hand consist of several bones. • The rib cage – The 12 sets of ribs protect the heart, lungs, liver, and spleen.

The Skeletal System (9 of 13) • The rib cage (cont’d) – The sternum is located in the front of the chest. – The xiphoid process is the pointed structure found at the bottom of the sternum.

The Skeletal System (10 of 13) • The pelvis – Serves as the link between the body and the lower extremities – Protects the reproductive organs and other organs located in the lower abdominal cavity • The lower extremity – Each lower extremity consists of the thigh and the leg.

The Skeletal System (11 of 13) • The lower extremity (cont’d) – The thighbone (femur) is the longest and strongest bone in the entire body. – The leg has two bones called the tibia and fibula. – The kneecap (patella) is a small, flat bone that protects the front of the knee joint. – The ankle and foot contain a large number of smaller bones.

The Skeletal System (12 of 13) • Joints – Where two bones come in contact with each other, a joint is formed. – Held together by supporting tissues called tendons and ligaments – Lubricated by a thin fluid that is contained in a sac surrounding the joint

The Skeletal System (13 of 13) • Joints (cont’d) – Three types of joints: • Fused joints • Hinge joints • Ball-and-socket joints

The Muscular System (1 of 2) • Skeletal muscles provide support and movement. – Alternately contract and relax Skeletal/Voluntary Muscle

The Muscular System (2 of 2) • Smooth muscles carry out automatic functions. – Also called involuntary muscles • Cardiac muscle is found only in the heart.

The Nervous System (1 of 3) • Governs the body’s functioning • Consists of the brain, the spinal cord, and the individual nerves that extend throughout the body

The Nervous System (2 of 3)

The Nervous System (3 of 3) • The brain is the body’s “central computer” and controls the following functions: – Thinking – Voluntary actions – Involuntary functions • The spinal cord is a long, tube-like structure that extends from the base of the brain.

The Digestive System (1 of 3) • Breaks down food into a form that can be carried by the circulatory system to the cells of the body • Food that is not used is eliminated as solid waste. • Major organs of the digestive system are located in the abdomen.

The Digestive System (2 of 3) • The digestive tract begins at the mouth and continues through these structures: – Throat – Esophagus – Stomach – Small intestine – Large intestine – Rectum – Anus

The Digestive System (3 of 3) • The digestive system also includes three other organs: – Liver – Gallbladder – Pancreas

The Genitourinary System (1 of 3) • Responsible for the body’s reproductive functions and for the removal of waste products • Major male reproductive organs: – The testes produce sperm. – The penis delivers sperm.

The Genitourinary System (2 of 3) • Major female reproductive organs: – The ovaries produce eggs. – The uterus holds the fertilized egg during pregnancy. – The egg released by the ovaries travels to the uterus through the fallopian tubes. – The external opening of the female reproductive system is called the birth canal (vagina).

The Genitourinary System (3 of 3) • The removal of waste products begins in the kidneys, which filter the blood to form urine. – The urine flows down from the kidneys through tubes (ureters) into the bladder. – The bladder collects and stores the urine before it passes out of the body through the urethra.

Skin (1 of 4) • Skin covers all parts of the body. • It has three major functions: – Protects the body against harmful substances in the environment – Regulates body temperature – Transmits information from the outside environment to the brain

Skin (2 of 4) • The dermis is the deeper, or inner, layer of the skin. • The epidermis is the outer layer of skin, which is located upon the dermis.

Skin (3 of 4)

Skin (4 of 4) • The skin is an effective barrier to bacteria and viruses as long as it is not broken by injury. • The skin can perceive or sense: – Touch – Pressure – Pain – Degrees of hot or cold

Stages of Life—Growth and Development (1 of 2) • Throughout a person’s life, the body changes constantly. – In an infant, the airway is very small and is easily obstructed by swelling or objects. – Because toddlers have poor coordination and balance, they are at high risk for falls. – School-aged children are physically active and prone to injuries from bicycle riding and other athletic mishaps.

Stages of Life—Growth and Development (2 of 2) • The body changes constantly. (cont’d) – Adolescents do not fully understand the consequences of dangerous actions. – Early adulthood is the period when most body systems are fully developed. – Middle adulthood is generally the time when body systems start to decline. – During late adulthood, these declines become more pronounced.

Vital Signs (1 of 3) • Most commonly measured vital signs: – Pulse (heart rate) – Respiration rate – Blood pressure • Normal vital signs change with age. – Normal pulse and respiratory rates decrease. – Systolic blood pressure increases.

Vital Signs (2 of 3)

Vital Signs (3 of 3) • Variations in normal vital sign values depend on three factors: – The person’s size – The person’s degree of physical conditioning – The medications that the person takes

Summary (1 of 4) • The respiratory system consists of the lungs and the airway. • The circulatory system consists of the heart (the pump), the blood vessels (the pipes), and blood (the fluid). • The skeletal system consists of the bones of the body.

Summary (2 of 4) • The muscular system consists of three kinds of muscles: voluntary (skeletal) muscles, smooth (involuntary) muscles, and cardiac (heart) muscles. • The nervous system consists of the brain, the spinal cord, and individual nerves.

Summary (3 of 4) • The digestive system consists of the mouth, esophagus, stomach, intestines, liver, gallbladder, and pancreas. • The genitourinary system consists of the organs of reproduction together with the organs involved in the production and excretion of urine.

Summary (4 of 4) • The skin protects the body from the environment, regulates the internal temperature of the body, and transmits sensations from the skin to the nervous system. • Vital signs change at different points of the life cycle.

Review 1. Which of the following patients is in the anatomic position? A. a man lying down on his back with his arms across his chest B. a woman standing and facing you, with arms at the sides and thumbs pointing outward C. a child on her left side with her right knee pulled up toward her stomach D. a man facing you with his feet 12″ apart and his hands interlocked behind his head

Review Answer: B. a woman standing and facing you, with arms at the sides and thumbs pointing outward

Review 2. When referring to the human body, the term proximal means: A. closest to the point where an arm or leg is attached. B. a position that is closer to the feet. C. a position on the back of the body. D. connected to the pelvis.

Review Answer: A. closest to the point where an arm or leg is attached.

Review 3. The respiratory system is responsible for: A. transporting oxygenated blood throughout the body. B. ensuring that the body has an adequate supply of red blood cells. C. removing carbon monoxide from the body. D. providing oxygen for the body and removing carbon dioxide.

Review Answer: D. providing oxygen for the body and removing carbon dioxide.

Credits • Opener: © Stephen Coburn/Shutter. Stock, Inc. • Background slide image (ambulance): © Comstock Images/Alamy Images • Background slide images (non-ambulance): © Jones & Bartlett Learning. Courtesy of MIEMSS.