Human Anatomy Review

Brentwood Ambulance Post 325

Terminology

Anatomy:

Physiology:

Pathophysiology:

Anatomy: The study of the structure of the body and its parts (what the body is made of).

Physiology: The study of how the body works (how the organs and body system functions).

Pathophysiology: They study of how diseases, injuries, or disorders change the normal function of the body.

Anatomical Position

Facing forward; palms facing outward

Planes of the body:

Coronal (Frontal) : Divides the body front / back

Sagittal (Lateral): divides the body : left / right

Mid-sagittal (midline): Divides the body into equal left and right halves

Transverse (axial): divides the body top / bottom

Positional terms:

Prone : Facing down

Supine: Facing up

Shock Position or Trendelenburg: Head down, legs up , increases BP ; Increases HR

Fowlers Position: Sitting up 45º or 90º

Recover Position: Right or left Recumbent

Directional Terms:

Cranial/ Superior: Top; Closer to head

Caudal / Inferior: Bottom; away from head

Ventral/ Anterior: Front

Dorsal/ Posterior: Back

Lateral: Away from midline

Medial: Close to midline

Proximal: Close to

Distal: Away from / far away

The importance of Anatomical Position

• The position patients are found help fit into pieces of a bigger puzzle

• You can determine in the most basic sense:

  • How it possibly happened

  • what the patient may have injured

  • Common conditions that may improve or determine the patients condition

The 4 Quadrants:

Right Upper Quadrant: Liver

Right Lower Quadrant

Left Upper Quadrant : Stomach

Left Lower Quadrant

Anatomical Terms

Right and left: YOUR PATIENT’S RIGHT AND LEFT!!!

Mid-Clavicular: Line that runs down the middle of the clavicle (the nipple of the breast)

Bilateral: Both Sides

Dorsal: Back side, or tip (dorsal fin of fish)

Ventral: opposite of dorsal, front side

Superficial VS. Deep

Superficial: Near or on the skin; scrapes and minor cuts

Deep: Farther Away from the surface; Gun shots or stabs

Joints

• Occurs wherever bones come in contact

• Consist of the ends of the bonds and the connecting and supporting tissues

  • Two types of joints:

    • Ball and Socket Joint

      • Allows rotation and bending

    • Hinge Joint

      • Motion restricted to flexion and extension

Skeletal System:

• Forms the body’s internal framework

• Made of 206 bones and cartilage

• Gives the body its shape

Two Divisions:

• Axial Skeleton

  • Skull

  • Spine (Vertebral Column)

  • Ribs (Thoracic Cage)

  • Sternum (Breast Bone)

• Function: Protects the brain, Spinal Cord, Heart, and Lungs

• Appendicular Skeleton:

  • Arms

  • Legs

  • Shoulders Clavicles & Scapulae

  • Pelvis

• Function: Allows Movement

Pelvis

• Connects the legs to the trunk

• Supports body weight

• protects pelvic organs

The pelvic girdle consists of:

• two coxae (hip bones)

• sacrum

• coccyx

• each pelvic bone is formed by fusion of the ilium, ischium, and pubis ( by the sacrum)

The Cranium

Structure of the Mandible

Functions of the Skeletal System

• Support

• Protection

• Movement

Injury Term: Fracture = Broken Bone

The Spinal Column

Coffee at 7 —> Cervical

Tea at 12 —> Thoracic

Licorice at 5 —> Lumbar

Soda at 5 —> Sacrum

Cookies at 4 —> Coccyx

The Thorax & Upper Extremities

• Formed by 12 thoracic vertebrae and pairs of ribs.

Thoracic cavity contains:

• Heart

• Lungs

• Esophagus

* Chest Injuries can cause multiple internal injuries.

Upper Extremities:

• Shoulder

• Clavicle

• Scapula

• Humerus

• Radius

• Ulna

• Carpals

• Metacarpals

• Phalanges

Lower Extremities:

• Pelvis

• Femur

• Patella

• Tibia

• Fibula

• Metatarsals

• Phalanges

Femur

• Femur (thigh) is the longest and strongest bone in the body

• The neck of the femur connects the head and shaft at a 125º angle.

• Can withstand 1,200-2,500 Ibs of compression force.

• Femur fractures are life-threatening because they can cause severe internal bleeding

• EMT care: stabilize the leg and provide immediate treatment/ transport

Knee

• The Knee is a complex structure and one of the most stressed joints in the body.

• It is the largest joint in the body

• It is vital for movement and vulnerable to injury

• The knee is a hinge joint responsible for weight-bearing and movement

It Consists of:

• Bones

• Meniscus

• Ligaments

• Tendons

Functions of the Knee:

• Supports the body on an upright position without muscles working

• Helps lower and raise the body

• Provides Stability

• Acts as a shock absorber

• Allows twisting of the leg

• Makes walking more efficient

• Helps propel the body forward

EMT importance:

• Knee injuries are common because the joint bears body weight

• Assess for pain, swelling, deformity, and limited movement

• Immobilize the injury if a fracture or serious ligament injury is suspected

Musculoskeletal System:

3 types of Muscles:

• Skeletal (Striated)- Voluntary; moves the body

• Smooth- Involuntary; found in organs and blood vessels

• Cardiac - Involuntary; found only in the heart

Skeletal muscles work with the skeletal system

They are under voluntary control

Function:

• Enable movement

• Maintain Balance

• Maintain Posture

• Muscles also help keep the body warm

• when you get cold, the body shivers involuntarily to produce heat

• shivering helps maintain homeostasis (the body’s normal internal balance).

Respiratory System

The respiratory system consists of all the structures involved in breathing (respirations).

It includes:

• Nose

• Mouth

• Thorat (Pharynx)

• Larynx (Voice Box)

• Trachea (Windpipe)

• Bronchi

• Bronchioles

• Lungs

• Diaphragm

• Chest Wall

• Muscles

• Accessory Muscles for Breathing

Functions:

• Oxygen (O2) passes from the lungs into the blood

• Carbon dioxide (CO2) is removed from the blood and exhaled

• The diaphragm is the primary muscle used for breathing

Upper and Lower Respiratory

Upper Airway:

1. Nose and Paranasal Sinuses

2. Oral Cavity

3. Pharynx

4. Larynx

Lower Airway:

1. Trachea

2. Lt and Rt Principal Bronchi

3. Secondary (Lobar) Bronchi

4. Segmental (Tertiary) bronchi

5. Terminal Bronchiole

6. Respiratory Bronchiole

7. Alveolar Duct and Sacs

Airway Adjuncts:

• EMTs can use airway adjuncts to help maintain an open airway

• Used for patients who are unresponsive or in cardiac arrest

Types:

• Oropharyngeal Airway (OPA) - used in unresponsive patients without a gag reflex

• Nasopharyngeal Airway (NPA) - Used in patients with a gag reflex or who are semi-conscious (unless facial/ skull trauma is suspected)

• Supraglottic Airway (i-gel) - Advanced airway device used during cardiac arrest or when a patient cannot maintain their airway.

Breathing

Inhalation (Active):

• Diaphragm and Intercostal muscles contract

• Thoracic Cavity increases in size

• Diaphragm moves downward

• Ribs Move upward and outward

• Air flows into the lungs

Exhalation (Passive):

• Diaphragm and intercostal muscles relax

• Thoracic cavity decreases in size

• Diaphragm moves upward

• Ribs move downward and inward

• Air flows out of the lungs

Muscles of Breathing:

• Diaphragm is the primary muscles of breathing

Also involved are:

Neck (Cervical) Muscles: help during difficult breathing

Intercostal Muscles: move the ribs during breathing

Abdominal muscles: help with forceful exhalation (coughing, sneezing)

Pectoral (Chest) muscles: Assist with breathing when a person is in respiratory distress.

Respiratory System Physiology:

Alveolar-Capillary Exchange:

• Occurs in the alveoli (air sacs of the lungs)

• Oxygen-rich air enters the alveoli during inhalation (inspiration)

• Oxygen-poor blood flows through the surrounding capillaries

• Oxygen (O2) moves from the alveoli —> capillaries (blood)

• Carbon dioxide (CO2) moves from capillaries —> alveoli

• CO2 is then exhaled from the lungs

Capillary - Cellular Exchange:

• Occurs between the capillaries and body cells

• Capillaries deliver oxygen (O2) to the cells

• Cells give carbon dioxide (CO2) to the Capillaries

• The blood carries CO2 back to the lungs to be exhaled

Chemical Control:

• The brain stem controls breathing

• It monitors carbon dioxide (CO2) levels in the blood and spinal fluid

• The primary reason for breathing is to remove excess carbon dioxide (CO2)

• Hypoxic Drive is a backup breathing drive that is triggered by low oxygen (O2) levels (Seen in some patients with chronic lung disease, such as (COPD)

Infant and Child Airway Considerations

• Mouth and nose are smaller and more easily obstructed

• Pharynx: The tongue takes up more space than in adults, making airway blockage more likely

• Trachea (windpipe): Narrower and more easily blocked

• Softer and More Flexible

• Diaphragm: Infants and Children depend more on the diaphragm for breathing because the chest wall is softer

Cardiovascular System

Heart: pumps blood throughout the body

Right Atrium: Receives oxygen-poor blood from the body and pumps it to the right ventricle

Left Atrium: Receives Oxygen-rich blood from the lungs and pumps it to the left ventricle

Right Ventricle: Pumps oxygen-poor blood to the lungs

Left Ventricle: Pumps Oxygen-Rich blood to the body

Valves: Prevent back flow and keep blood flowing in one direction

Arteries:

Coronary Arteries: Supply the heart muscle with blood

Aorta:

• Largest artery in the body

• Begins at the left ventricle of the body

• travels through the chest (thoracic cavity) and abdomen (abdominal cavity)

• Splits near the navel into the iliac arteries

Pulmonary Artery:

• Starts at the right ventricle

• Carries Oxygen-poor blood to the lungs

Carotid Arteries:

• Located in the neck

• Supply blood to the head and brain

• Pulse: Felt on either side of the neck

Femoral Artery:

• Located in the thigh/groin

• Supplies the lower extremities

• Pulse: Felt in the groin

Radial Artery:

• Located in the forearm / wrist

• Pulse: Felt on the side of the wrist

Brachial Artery:

• Located in upper arm

• Pulse: Felt inside the arm between the shoulder and elbow

• used to measure blood pressure

Posterior Tibial Artery:

• Located behind the medial Malleolus (inside ankle bone)

• Pulse: Felt behind the inside ankle

Dorsalis Pedis Artery:

• Located on the top (anterior surface) of the foot

• Pulse: Felt on the top of the foot

Arterioles:

• Smallest branches of arteries

• Carry blood from arteries to capillaries

Capillaries:

• Tiny blood vessels that connect arterioles to venules

• Found throughout the entire body

• site where oxygen, nutrients, carbon dioxide, and waste products are exchanged between then blood and body cells.

Venules

• The smallest veins

• collect blood from the capillaries

• Merge together to form larger veins, which return blood to the heart

Veins

• Carry Blood back to the heart

• Usually carry oxygen-poor (deoxygenated) blood, expect for the pulmonary veins

Pulmonary Veins

• Carry oxygen-rich blood from the lungs to the left atrium if the heart

• Exception: They are veins that carry oxygen-rich blood

Venae Cavae:

• Superior Vena Cava : Returns Oxygen-Poor blood from the head, neck, arms, and chest to the right atrium

• Inferior Vena Cava: Returns Oxygen-Poor Blood from the abdomen, pelvis, and legs to the right atrium

Heart Circulation

Blood Pressure: 120/80 mmHg

Systolic Pressure:

• The pressure exerted against the walls of the arteries when the left ventricle contracts

• Represents the highest pressure in the arteries

• The top # in a blood pressure reading

Diastolic Pressure:

• The pressure exerted against walls of the arteries when the left ventricle is at rest (relaxes)

• Represents the lowest pressure in the arteries

• The bottom # in a blood pressure reading

Organs: The Digestive System: Anatomy

Abdomen:

• The Second major body cavity

• Contains the major organs involved in digestion and excretion

• Divided into 4 quadrants:

  • Right Upper Quadrants (RUQ)

  • Left Upper Quadrants (LUQ)

  • Right Lower Quadrants (RLQ)

  • Left Lower Quadrant (LLQ)

Mouth:

Includes:

• Lips

• Cheeks

• Gums

• Teeth

• Tongue

• Begins the process of digestion

Salivary Glands:

• Produce Saliva to help break down food

Oropharynx:

• Passageway that connects the mouth to the esophagus

Esophagus:

• Tube that moves food from the mouth to the stomach

Stomach:

• Breaks down food using acid and enzymes

Pancreas:

• Produces enzymes that help digest food

• helps regulate blood sugar

Liver:

• Produces bile

• Helps process nutrients and Remove toxins

Bile Ducts:

• Carry bile from the liver to the Small intestine

Small Intestine:

• Main site where nutrients are absorbed into the bloodstream

Large Intestine:

• Absorbs water and forms waste (feces)

Appendix:

• Small pouch attached to the large intestine

Rectum:

• Stores feces before elimination

GI Pathway (Food Route):

• Mouth —> Oropharynx —> Esophagus —> Stomach —> Small Intestine —> Large Intestine —> Rectum —> Outside the Body

The Integumentary System (Skin):

Skin:

• the largest single organ in the body

• made up of 2 layers:

  • Epidermis: the outer (superfical) layer

  • Dermis: the inner (deeper) layer

Subcutaneous Tissue (Hypodermis)

• located beneath the skin

• contains fat (adipose tissue)

Functions:

• insulates the body

• stores energy

• cushions and protects underlying tissues

Three major functions of the skin:

1. Protects the body from the environment (injury, bacteria, chemicals)

2. Regulates body temperature (through sweating and blood vessel changes

3. Transmits information from the environment to the brain (touch, pain, pressure, temperature)