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Body Positions

  • Supine: Lying face up.
  • Prone: Lying face down.
  • Lateral Recumbent: Lying on his or her side. Can be left or right lateral recumbent.
  • Fowler's Position: Lying as in a reclining chair, with upper body elevated at a 45 to 60 degree angle.
  • Semi-Fowler's Position: Similar to a Fowler's Position, but with the upper body elevated below a 45 degree angle.
  • Trendelenburg Position: Lying supine with feet elevated above the head.
  • Shock Position: Lying supine with feet elevated approximately 12 inches.

Anatomical Planes

Left and right (From the patient's point of reference)

  • Midline, Midspinal line, and the Sagittal Plane: Vertical line through the center of the body that divides left and right. The midline intersects the nose and navel on the front of the body. The midspinal line runs parallel to the spine on the back of the body. The sagittal plane includes both the midline and the midspinal line and divides the body into left and right planes.
  • Midclavicular and Midscapular: Between the midline and the outer side of the body (between the midline and the armpit). Midclavicular is a vertical line bisecting the clavicle (collarbone) on the front of the body, and midscapular is a vertical line bisecting the scapular (shoulder blade) on the back of the body.
  • Medial and Lateral: Towards or away from the midline (towards the middle or to the sides).
    • Bilateral: both sides
    • Unilateral: one side
    • Ipsilateral: same side
    • Contralateral: opposite side

Anterior and Posterior (Front and back)

  • Ventral and Dorsal: Same as anterior and posterior.
  • Midaxillary Line and Frontal Plane: Vertical line intersecting the armpit and the ankle that divides the body into anterior and posterior. The frontal plane includes the
  • midaxillary line and divides the body into anterior and posterior planes.
  • Anterior Axillary Line: Vertical line between the midaxillary line and the outer anterior (nipples).
  • Posterior Axillary Line: Vertical line between the midaxillary line and the outer posterior (back).

Superior and Inferior (Above and below )

  • Transverse Line and Plane: Horizontal line at the waist that divides the body into superior and inferior (above and below). The transverse plane includes the transverse line and divides the body into superior and inferior planes.

Other Designations

  • Proximal or Distal: Near or far from the point of reference.
  • Plantar and Palmar: Plantar refers to the soles of the feet and palmar refers to the palm of the hand.
  • Quadrants: From the patient's perspective, the four regions of the abdomen. LUQ (left upper quadrant), LLQ (left lower quadrant), RUQ (right upper quadrant), and RLQ (right lower quadrant).

The Musculoskeletal System

  • Includes muscle, bone, tendons (connecting muscle to bone) and ligaments (connecting bone to bone).
  • Functions include structural, protection, motion, mineral storage and blood cell production. Bone injuries can result in substantial blood loss (1-2 L from a fractured femur and up to 2 L from a fractured pelvis).
  • Refer to any anatomy text for detailed nomenclature.

The Muscular System

  • Skeletal Muscle: Striated, voluntary, can be consciously controlled. Also called skeletal muscles.
  • Smooth Muscle: Smooth, involuntary, cannot be consciously controlled.
  • Cardiac Muscle: Striated, branched, involuntary.

The Skeletal System

  • Consists of six basic components: The skull, spinal column, thorax, pelvis, upper extremities (arms), and lower extremities (legs).

The Skull

  • Cranium: brain case. Encloses the cranial cavity. Contains flat bones.
    • Occipital: back of the head.
    • Parietal: the upper sides.
    • Temporal: the temples.
    • Frontal: forehead.
  • Face: irregular bones
    • Orbits: eye sockets.
    • Nasal Bones: nose bed.
    • Maxillae: upper jaw.
    • Zygomatic: cheek bones.
    • Mandible: lower jaw.

The Spinal Column

  • Verbebrae: irregular bones that make up the spinal column. 33 vertebrae intercalated with intervertebral discs make up the spinal column, which is divided into 5 parts.
    • Cervical: the neck consists of 7 verbebrae C1-C7.
    • Thoracic: upper back consists of 12 verbebrae T1-T12. The 12 thoracic ribs are attached here.
    • Lumbar: lower back consists of 5 vertebrae L1-L5. These are the least mobile.
    • Sacral: back wall of pelvis consists of 5 fused vertebrae S1-S5.
    • Coccyx: tailbone consists of 4 fused vertebrae.

The Thorax

  • The ribs: there are 24 ribs arranged into 12 pairs, which are attached at the back to the 12 thoracic vertebrae.
    • True ribs: the first 7 pairs attached at the front to the sternum.
    • The next 3 pairs attach at the front to the true ribs.
    • False ribs: last 2 pairs are not attached at the front. Also called floating ribs.
  • Sternum: breastbone.
    • Manubrium: the superior portion of the sternum that attaches the clavicle.
    • Body: the middle portion of the sternum that attaches the ribs.
    • Xiphoid process: the inferior portion of the sternum.

The Pelvis

  • Sacrum and coccyx: the back of the pelvis.
  • Ilium: from the Iliac crest (the "wings" on the sides of the pelvis) to the formation of the acetabulum.
  • Acetabulum: socket for hip joint.
  • Ischium: the lower back portion. Supports weight while sitting.
  • Pubis: the lower front portion. Area of the genitals. The left and right sides are joined at the pubic symphysis.

The Upper Extremities

  • Consists of the upper limbs from the shoulder to the fingers.
  • The Clavicle, Scapula, and the Acromion: the collar bone (clavicle) and the shoulder blade (scapula) forms the pectoral (shoulder) girdle, which connects the upper limb. The acromion, or acromial process is the tip on top of the shoulder.
  • The Humerus: the head of the humerus fits in the ball and socket joint of the shoulder. The distal end of the humerus ends at the hinge joint of the elbow.
  • Olecranon: the elbow, formed by the proximal end of the ulna.
  • The Radius and Ulna: from the elbow, two bones form the forearm. The radius is on the thumb side (lateral with palm facing the front) and the ulna is on the pinky side (medial). Both bones end at the wrist joint.
  • Carpals, Metacarpals and Phalanges: makes up the hand from the wrist (carpals) to the hands (metacarpals) to the fingers (phalanges).

The Lower Extremities

  • Consists of the legs from the hip to the toes.
  • Femur: the head of the femur fits into the acetabulum socket in the hip. The femur ends at the patella (the knee).
  • Patella: kneecap.
  • Tibia and Fibula: The bones of the lower leg. The tibia is larger of the two and forms the shin, the distal end of which forms the medial ankle. The fibula is parallel and lateral to the tibia, the distal end of which forms the lateral ankle.
  • Malleolus: the ankle knob. Can be medial or lateral.
  • Calcaneus: heel bone
  • Tarsals, Metatarsals and Phalanges: makes up the foot from the ankles (tarsals) to the foot (metatarsals) to the toes (phalanges).


  • Motion
    • Flexion and Extension: bending (flexing) and straightening (extending).
    • Adduction and Abduction: movement toward (adduct) and away from (abduct) the midline.
    • Circumduction: circuluar movement. Includes all the above motion.
    • Supination and Pronation: turning the forearm to make the palm face the front (supination) or the back (pronation).
  • Structure
    • Ball-and-Socket: circular in shape, allows for circumduction, the widest range of motion. Examples include the shoulder and hip.
    • Hinged Joint: shaped like a door hinge, allows for flexion and extension. Examples include the elbow, knee and finger.
    • Pivot Joint: semi-circular ring shape, allows for turning motion. Examples include the C1-C2 vertebrae and the wrist.
    • Gliding Joint: planar in shape, allows for sliding motion. Examples include the small bones in the hands and feet.
    • Saddle Joint: saddle (reciprocal concave-convex) in shape, allows for limited circumduction without axial rotation. An example include the carpal-metacarpal joint of the thumb.
    • Condyloid Joint: ovular in shape, allows for limited circumduction without axial rotation. An example include the wrist.

The Respiratory System

  • The Nose and Mouth: air enters here. The nasal cavity filters, warms and moistens incoming air.
  • The Pharynx: the mouth leads to the oropharynx and the nose leads to the nasopharynx. Both merge in the throat and then separate into either the esophagus (for food to enter the stomach) or the trachea (for air to enter the lungs).
  • The Epiglottis: flap of cartilage that protects the trachea from food during swallowing.
  • The Larynx: houses the vocal cords, which is protected by the thyroid cartilage (Adam's apple). The most inferior part of the larynx is the cricoid cartilage (ring of cartilage).
  • The Trachea: the wind pipe, which branches into two bronchi.
  • The Bronchi, bronchioles and Alveoli: the left and right bronchi further branches into bronchioles, which end in sacs of alveoli. Gas exchange takes place across the surface of the alveoli.
  • The Lungs: organ for gas exchange, which houses all of the alveoli. The lung is lined with connective tissue called the visceral pleura, which is in turn surrounded by the parietal pleura. This double membrane creates an intermembrane space called the pleural cavity with negative pressure that keeps the lung from collapsing.
  • The Diaphragm and Intercostal Muscles: muscles for breathing. The diaphragm is the dome shaped muscle beneath the lungs. Pulls down when contracting to create the negative pressure required for breathing. The intercostal muscles are the muscles between the ribs that expand the rib cage when contracting, which creates the negative pressure in the lungs required for breathing.

Notes on Respiration

  • Adequate rate of breathing
    • 12-20 breaths per minute for a typical adult, 20-22 for the elderly, 15-30 for children, and 25-50 for infants.
    • Effortless.
    • Regular in rhythm.
    • Clear of unusual sounds.
    • Adequate tidal volume (chest rise, breathing sounds).
  • Inadequate breathing
    • unusual rate
    • strained (nasal flaring, use of accessory muscles, "seesaw" movement in infants, head bobbing due to fatigue, gasping, grunting in newborns)
    • irregular
    • unusual breath sounds (airway obstruction)
    • Inadequate tidal volume (unusual breath sounds, inadequate or irregular chest expansion,
  • Infants have:
    • Smaller nose, mouth, and narrower airway: more easily obstructed.
    • Proportionally larger tongue: can obstruct airway.
    • Softer cricoid cartilage: cricoid pressure will not help intubation.
    • Rely more on diaphragm for breathing: movement of the abdomen as signs for respiratory distress rather than chest movement in adults.

The Circulatory System

The Heart

  • Cardiac muscle, contracts by itself, has its own pacemaker. involuntarily regulated by the autonomic nervous system. Consists of four chambers: left and right atria and ventricles. Valves (Tricuspid, pulmonary, mitral, aortic) exist to prevent the backflow of blood.

The Circulation

  • Superior and Inferior Vena Cava: deoxygenated blood from the body enters the heart via these veins.
  • Right Atrium: deoxygenated blood first enters into this chamber.
  • Tricuspid Valve: valve preventing backflow between right atrium and right ventricle.
  • Right Ventricle: deoxygenated blood gets pumped to the lungs here.
  • Pulmonary Valve: valve preventing backflow between right ventricle and pulmonary artery.
  • Pulmonary Artery: deoxygenated blood flows to the lungs via this artery.
  • Lungs: gas exchange occurs here.
  • Pulmonary Veins: oxygenated blood carried to the heart via this vein.
  • Left Atrium: oxygenated blood first enters this chamber.
  • Mitral Valve: valve preventing backflow between left atrium and left ventricle. Also called the bicuspid valve.
  • Left Ventricle: oxygenated blood gets pumped to the body here.
  • Aortic Valve: valve preventing backflow between left ventricle and the aorta.
  • Aorta: oxygenated blood flows to the rest of the body via this artery.

  • With the exception of pulmonary arteries and veins, all arteries carry oxygenated blood and all veins carry deoxygenated blood.
  • Blood Pressure: force exerted on walls of the artery.
    • Systolic: during ventricular contraction.
    • Diastolic: during ventricular relaxation.
  • Hydrostatic Pressure: caused by blood pressure and volume that influences fluid migration across capillary walls. High hydrostatic pressure pushes fluid out of capillaries causing edema (swelling in tissues).
  • Perfusion: the delivery of oxygen and other nutrients to cells and wastes away from them. Adequate perfusion depends on adequate blood circulation.
  • Hypoperfusion: also called shock, is inadequate perfusion. Can be caused by large loss of blood volume.
  • Gas transport
    • Oxygen: 97% bound to hemoglobin, 3% dissolved in plasma.
    • Carbon Dioxide: 70% as bicarbonate ion, 23% attached to hemoglobin, 7% dissolved in plasma.

The Arteries and Pulses

  • Aorta: the largest artery in the human body, carries freshly oxygenated blood directly from the heart.
  • Coronary Arteries: supplies the heart.
  • Carotid Arteries: supplies the brain. Pulse on sides of the neck.
  • Femoral Arteries: supplies the groin and legs. Pulse on the groin.
  • Dorsalis Pedis Arteries: supplies the dorsal surface of the foot. Pulse on top of the foot.
  • Posterior Tibial Arteries: supplies the posterior leg and the plantar foot. Pulse between the medial ankle and heel (posterior to the medial malleolus).
  • Brachial Arteries: supplies the arm. Pulse between elbow and armpit.
  • Radial Arteries: supplies the hand, wrist and forearm. Pulse on the wrist proximal to the thumb.
  • Pulmonary Arteries: the only artery to carry deoxygenated blood. Carries deoxygenated blood to the lungs.

Other Blood Vessels

  • Arterioles: the smallest artery. Branches off from arteries. Supplies blood to the capillaries.
  • Capillaries: the smallest blood vessels with walls the thickness of a single-cell.
  • Venules: the smallest veins. Merge into veins.
  • Veins: carries blood back to the heart.


  • Red Blood Cells: carry oxygen, contains hemoglobin.
  • White Blood Cells: part of the immune system to fight off infection.
  • Platelets: responsible for clot formation.
  • Plasma: the liquid part of the blood. Contains albumin to maintain osmotic gradient.

The Nervous System

The Central Nervous System

  • Brain
    • Cerebrum: largest, outermost portion, responsible for memory, thinking, and voluntary control.
    • Cerebellum: small lobe on the back of the head below the cerebrum, responsible for muscle coordination and balance.
    • Brainstem: Includes the mesencephalon, the pons, and the medulla oblongata. The medulla is responsible for respiratory, cardiac and vasomotor (blood vessel dilation or constriction) control.
  • Spinal Cord: an extension of the brain stem that ends at the L2 vertebrae. responsible for conducting nerve impulses to and from the brain.

The Peripheral Nervous System

  • Voluntary: controls skeletal muscles.
  • Autonomic: controls smooth muscles and regulates cardiac muscles.
    • Sympathetic: prepares for fight or flight.
    • Parasympathetic: normal body function, relaxing.

The Endocrine System

  • Pituitary: master gland that regulates the activity of other glands. Located at the base of the brain.
  • Thyroid: regulates metabolism, growth and development. Produces calcitonin, which deposits calcium from blood to bone. Located in the anterior neck.
  • Parathyroid: produces parathyroid hormone that metabolizes bone calcium and phosphorous. Located behind the thyroid.
  • Adrenal: secretes epinephrine (adrenaline) and norepinephrine. Also secretes other hormone that regulates kidney function and conserves water in the body. Located above the kidneys.
  • Gonads: produces sex hormones (ovaries produce estrogen and testes produce testosterone).
  • Islets of Langerhans in the Pancreas: produces glucagon (increase blood sugar level) and insulin (decrease blood sugar level).

The Skin

  • Three Layers
    • Epidermis: outermost, contains dead and dying cells and melanin (skin color pigment).
    • Dermis: below epidermis, thicker, contains blood vessels, hair follicles, sweat and oil glands and nerves. The connective tissue present here gives skin its strength and elasticity.
    • Subcutaneous Layer: deepest layer, contains fatty tissue.
  • The largest organ in the body
  • Protection from environment and pathogens
  • Sensory: heat, cold, touch, pain and pressure.
  • Regulation of water and electrolytes by sweating.

The following body systems are beyond the required curriculum for an EMT.

The Digestive System

  • Mouth: mechanical digestion starts by chewing. Limited chemical digestion of starch.
  • Stomach: hollow sac of muscle, lined on the inside with mucus. Secretes acidic gastric juices. Starts chemical digestion of food.
  • Pancreas: produces enzymes and secrete them in pancreatic juices.
  • Liver: produces bile to emulsify fats. Participates in metabolism of toxic substances.
  • Spleen: no function
  • Gallbladder: stores bile made by the liver.
  • Small Intestine: chemical digestion and nutrient absorption site. Consists of the duodenum, jejunum, and ileum.
  • Large Intestine: water absorption site.

Urinary System

  • Kidneys: blood filtration. Makes urine.
  • Ureter: carries urine from kidneys to the bladder.
  • Bladder: stores urine.
  • Urethra: carries urine from the bladder to outside of the body.

Reproductive System

  • Female
    • Ovaries: stores immature ovum. An ovum matures every month and is released to the fallopian tubes.
    • Fallopian Tube: site of fertilization. Carries mature ovum to the uterus.
    • Uterus: Fertilized egg (zygote) implants here. Embryo develops here.
    • Vagina: Babies are delivered through the vagina.
  • Male
    • Testes: makes sperm.
    • Epididymis: stores mature sperm.
    • Vas Deferens, Ejaculatory Duct, Urethra and Penis: Transports ejaculated sperm.

Response to Epinephrine and Norepinephrine

  • Alpha 1: vasoconstriction of skin blood vessels, stimulates sweat glands. Causes skin to become cool, pale and clammy.
  • Alpha 2: regulate the release of Alpha 1.
  • Beta 1: increase the heart's rate, force of contraction, and speed of impulse conduction.
  • Beta 2: cause smooth muscles to dilate, especially in the bronchioles.


  • Aerobic: when oxygen level is adequate, the cells utilize oxygen for metabolism and generate carbon dioxide water. This is the most efficient form of metabolism and occurs during adequate perfusion.
  • Anaerobic: when oxygen level is inadequate, the cell undergo metabolism without oxygen to generate lactic acid, which is toxic if allowed to accumulate. Anaerobic metabolism is inefficient and occurs during inadequate perfusion.