CH.7
Prefixes, Suffixes, and Medical Terms
Prefixes and suffixes shown with examples:- hypo- (below normal) → hypovolemic: pertaining to a below-normal volume of blood
hyper- (above normal) → hyperglycemia: condition of an above-normal blood glucose level
a- (without, no) + pne/o- (breathing) → apnea: condition of no breathing
tachy- (fast) + cardi/o- (heart) + -ia → tachycardia: condition of a fast heart rate
brady- (slow) + pne/o- (breathing) + -a → bradypnea: condition of a slow breathing rate
Terms shown in context: cystoureteropyelonephritis (an example of a complex medical term) and the idea that terminology is often learned or verified via quick lookups (e.g., Google) to avoid mispronunciations or errors.
Anatomical Terms and Anatomical Position
Anatomical position reference: standing, facing forward, arms at the sides with palms forward.
Lines of reference and location terms include: midline, midclavicular line, midaxillary line.
Terms of direction you must know: right vs. left (patient’s right vs. patient’s left); anterior (ventral) vs. posterior (dorsal); medial vs. lateral; superior vs. inferior; proximal vs. distal; plantar vs. palmar.
Joint motions: flexion, extension, abduction, adduction; pronation, supination.
Abdominal Quadrants and Organ Types
Abdominal Quadrants: The abdomen is typically divided into four quadrants (right upper, left upper, right lower, left lower) or nine regions to pinpoint organ locations and aid in assessment. Injuries to the abdomen can affect either solid or hollow organs, each with distinct clinical implications in emergencies.
Solid Organs: These organs are dense and rich in blood supply. When injured, they tend to bleed significantly, leading to internal hemorrhage.
Liver: The largest internal organ, located primarily in the right upper quadrant. Critical for detoxification, protein synthesis, and bile production. Highly vascular.
Spleen: Located in the left upper quadrant. Filters blood, removes old red blood cells, and plays a role in the immune system. Very fragile and prone to rupture with trauma.
Kidneys: Paired organs located bilaterally in the retroperitoneal space, posterior to the abdominal cavity. Essential for filtering blood, producing urine, and regulating blood pressure.
Pancreas: Located retroperitoneally, largely in the upper abdomen. Functions as both an exocrine gland (producing digestive enzymes) and an endocrine gland (producing hormones like insulin and glucagon).
Ovaries: Paired female reproductive glands located in the pelvic cavity. Produce ova and female hormones.
Uterus: Female reproductive organ located in the pelvic cavity. Supports fetal development during pregnancy.
Adrenal Glands: Small glands located on top of each kidney (retroperitoneal). Produce hormones such as epinephrine and norepinephrine.
Prostate Gland: Male reproductive gland located below the bladder. Produces seminal fluid.
Hollow Organs: These organs are typically tubular or sac-like and contain fluids or other contents. When injured, they are prone to leakage or rupture, potentially spilling their contents into the abdominal cavity and causing peritonitis (inflammation of the peritoneum) or sepsis.
Stomach: Located in the left upper quadrant. Initiates chemical and mechanical digestion of food.
Small Intestine: Extends from the stomach to the large intestine, occupying much of the central and lower abdomen. The primary site for nutrient absorption. Divided into the duodenum, jejunum, and ileum.
Large Intestine: Frames the small intestine, including the cecum (with appendix), ascending colon, transverse colon, descending colon, and sigmoid colon. Absorbs water and electrolytes, forms and stores feces.
Gallbladder: Small organ located under the liver (right upper quadrant). Stores and concentrates bile.
Urinary Bladder: Located in the pelvic cavity. Stores urine until it is excreted.
Ureters: Muscular tubes that carry urine from the kidneys to the bladder.
Appendix: A small, finger-like projection from the cecum of the large intestine, often associated with immune function.
Fallopian Tubes: Female reproductive tubes connecting the ovaries to the uterus, for egg transport.
Vagina: Female reproductive canal.
Seminal Vesicles and Vas Deferens: Male reproductive accessory glands and ducts involved in sperm transport and fluid production.
Body Positions and Recovery Position
Supine: laying on back, face up.
Prone: laying face down.
Right lateral recumbent: laying on the right side.
Left lateral recumbent: laying on the left side (recovery position).
Fowler’s position: head of bed elevated 45–60°.
Semi-Fowler’s: head of bed elevated 30–45°.
Trendelenburg position and other shock positions are no longer recommended due to breathing and intracranial pressure issues; contraindicated in suspected spinal injury scenarios.
Position-identification exercise: name that position (prone, right lateral recumbent, supine, left lateral recumbent).
Body Cavities and Serous Membranes
Major body cavities: cranial cavity, vertebral canal, thoracic cavity, abdominopelvic cavity (with abdominal and pelvic subdivisions).
Thoracic cavity contains pleural cavities, pericardial cavity, and mediastinum; lung serosa is pleura; heart serosa is pericardium.
Abdominopelvic cavity contains abdominal organs (stomach, liver, spleen, gallbladder, intestines, etc.) and pelvic organs (bladder, parts of large intestine, reproductive organs).
Serous cavities: pleural, pericardial, and peritoneal cavities.
Peritoneum is the serous membrane lining the abdominal cavity and covering abdominal organs; mesentery is the supporting tissue that attaches the intestines to the posterior abdominal wall.
Retroperitoneal Organs: SAD PUCKER Mnemonic
SAD PUCKER stands for retroperitoneal viscera:- S = Suprarenal glands (adrenal glands)
A = Aorta/IVC
D = Duodenum (except first portion)
P = Pancreas (head and neck; not tail)
U = Ureters
C = Colon (ascending and descending; not transverse/descending portions listed as retroperitoneal in some references)
K = Kidneys
E = Esophagus
R = Rectum
Note: Intraperitoneal organs are not included in SAD PUCKER; this mnemonic helps remember retroperitoneal locations.
Musculoskeletal System Overview
Components: bones, ligaments (bone-to-bone), tendons (muscle-to-bone), muscles, and other connective tissues.
Four functions: give body shape; protect vital organs; enable movement; store minerals and produce blood cells.
Six basic skeletal components: skull, spinal column, thorax, pelvis, upper extremities, lower extremities.
Common bone injuries: bone is living tissue; fractures can cause bleeding from bone or surrounding tissue (bone bleeding volumes provided for major bones: femur 1,000–2,000 mL; pelvis ~2,000 mL).
Skull: cranial bones (occipital, parietal, frontal, temporal) and facial bones (14 total).
Spinal column: 33 vertebrae with intervertebral disks; cervical 7, thoracic 12, lumbar 5, sacral 5, coccygeal 4.
Thorax: ribs (true, false, floating); sternum (manubrium, body, xiphoid process).
Pelvis: pelvic girdle comprised of sacrum, coccyx, pelvic bones (ilium, pubis, ischium).
Limbs: upper extremities (humerus, radius, ulna, carpals, metacarpals, phalanges); lower extremities (femur, patella, tibia, fibula, tarsals, metatarsals, phalanges).
Joints: joints may be immovable, slightly movable, or movable (freely movable joints include ball-and-socket and hinge joints).
Common phrase: a “broken hip” is typically a femoral neck fracture.
Muscular System
Muscle types:- Skeletal muscle: voluntary; allows deliberate movement.
Cardiac muscle: heart muscle; generates its own electrical impulses; requires constant blood supply.
Smooth muscle: involuntary; found in blood vessels, digestive tract, respiratory tract, and other structures.
Muscles generate movement via contraction in response to nerve impulses.
Respiratory System and Ventilation
Division: upper and lower respiratory tracts, separated at the larynx (voice box).
Primary functions: respiration (gas exchange), ventilation (air movement), maintain acid-base balance.
Major respiration muscles: diaphragm (60–70% of respiratory effort) and intercostal muscles (30–40%); C3–5 keeps the diaphragm alive (high spinal injury at C3–5 or above impairs both diaphragm and intercostals).
Major structures: nose, nasal cavity, mouth, pharynx (nasopharynx, oropharynx, laryngopharynx), epiglottis, larynx, vocal cords, trachea, bronchi, bronchioles, alveoli, alveolar capillary beds, pleura.
Upper tract functions: warm, moisten, and filter air; epiglottis protects the trachea from liquids/food.
Ventilation mechanics:- Pressure changes drive air movement; expansion/contraction of the thoracic cage creates a negative pressure system.
Gas movement: from higher to lower pressure; atmospheric pressure ~760 mmHg; intrapulmonary pressure fluctuates during inhalation/exhalation.
Inhalation: diaphragm and external intercostals contract; thoracic volume increases; intrapulmonary pressure falls; air enters.
Exhalation: diaphragm and intercostals relax; thoracic volume decreases; intrapulmonary pressure rises; air exits.
Gas transport and diffusion:- Gases diffuse from areas of high concentration to low concentration across alveolar-capillary membranes.
External respiration: gas exchange between alveoli and capillaries.
Internal respiration: gas exchange between capillaries and body tissues.
Oxygen transport:- Oxygen is primarily transported bound to hemoglobin in red blood cells.
Each hemoglobin molecule can carry up to four O2 molecules.
Saturation reading example: one O2 bound corresponds to 25% saturation; four bound corresponds to 100% saturation.
Without hemoglobin, oxygen delivery to tissues is severely compromised.
Carbon dioxide transport:- The majority of CO2 is transported as bicarbonate in plasma; in the lungs CO2 is released when bicarbonate reverts to CO2 and is exhaled.
Circulatory System and Blood Physiology
Blood components:- Red blood cells (RBCs/Erythrocytes): transport O2 and CO2 via hemoglobin; give blood its red color.
White blood cells (WBCs/Leukocytes): immune defense.
Platelets (Thrombocytes): form clots to stop bleeding.
Plasma: the liquid portion; transports nutrients, wastes, hormones, etc.; ~55% of blood; ~91% water; contains plasma proteins.
Blood vessels:- Arteries: carry oxygenated blood away from the heart (except pulmonary arteries); high-pressure vessels with muscular walls that can dilate or constrict.
Veins: carry deoxygenated blood back to the heart (except pulmonary veins); low-pressure vessels.
Capillaries: tiny, low-pressure vessels where exchange with tissues occurs.
Cardiac dynamics:- Cardiac output (CO) = Heart Rate (HR) × Stroke Volume (SV).
Blood pressure (BP) is influenced by CO and systemic vascular resistance (SVR):
Normal adult heart rate:
Pulse assessment: central pulses (carotid, femoral); peripheral pulses (radial, brachial, posterior tibial, dorsalis pedis).
Blood volume and pressures:- Hydrostatic pressure pushes fluid out of capillaries; plasma oncotic pressure pulls water into capillaries.
Balance of hydrostatic and oncotic pressures maintains vascular volume; imbalance leads to edema or hypovolemia.
Right-sided heart failure can increase systemic hydrostatic pressure causing edema; low plasma proteins (albumin) reduce oncotic pressure, leading to edema or volume overload.
Hemodynamics recap:- Systemic Vascular Resistance (SVR) = resistance to blood flow through vessels.
Flow from heart to body: Vena Cava → Right Atrium → Tricuspid Valve → Right Ventricle → Pulmonary valve → Pulmonary Arteries → Lungs → Pulmonary Veins → Left Atrium → Bicuspid Valve → Left Ventricle → Aorta → Body.
The heart is surrounded by a serous cavity (pericardium).
Nervous System Overview
Divisions:- Central Nervous System (CNS): brain and spinal cord.
Peripheral Nervous System (PNS): all nerves outside CNS; includes sensory (afferent) and motor (efferent) pathways.
Somatic (voluntary) nervous system vs. Autonomic (involuntary) nervous system.
Autonomic divisions: Sympathetic (fight-or-flight) and Parasympathetic (rest-and-digest).
CNS and meninges:- CNS protected by three meningeal layers and cerebrospinal fluid (CSF).
Brainstem contains respiratory, cardiac, and vasomotor centers; medulla oblongata key for autonomic control.
Brain and spinal cord anatomy:- Brain regions: brainstem (mesencephalon, pons, medulla), cerebrum (sensation, thought, memory; voluntary movements), cerebellum (coordination and balance).
Spinal cord transmits sensory and motor impulses; protected by vertebral column, meninges, and CSF.
Functional divisions of the PNS:- Sensory (afferent) nerves carry impulses from the body to the brain.
Motor (efferent) nerves carry impulses from the brain to the body.
Somatic nervous system controls voluntary muscles; Autonomic controls smooth and cardiac muscles.
Sympathetic effects include pupil dilation, increased heart rate, bronchodilation, decreased saliva, increased glucose release, and more; Parasympathetic effects include pupil constriction, slowed heart rate, bronchoconstriction, increased saliva, and digestive activities.
Homeostasis concept: balance between sympathetic and parasympathetic activity maintains physiological stability.
Endocrine System Overview
Endocrine system is made of ductless glands that secrete hormones to regulate body functions; hormones act as chemical messengers.
Adrenal glands:- Located on top of kidneys.
Produce epinephrine and norepinephrine which act on the sympathetic nervous system.
Effects: Alpha1/Alpha2 cause vasoconstriction; Beta1 increases heart rate/contractility; Beta2 causes bronchodilation.
Epinephrine and norepinephrine help compensate for shock.
Pancreas:- Hormones include insulin (Beta cells) and glucagon (Alpha cells).
Insulin enables glucose entry into cells; without insulin leads to cellular energy starvation and hyperglycemia.
Glucagon converts glycogen to glucose to raise blood sugar.
Integumentary System
Structures: Skin (epidermis, dermis, subcutaneous layer), hair and follicles, nails, glands (sweat and oil), nerve endings.
Functions: protect against environment and pathogens; regulate body temperature; sense heat, cold, touch, pain, and pressure; regulate water and electrolyte balance.
Digestive System Overview
Structures and membranes:- Peritoneum: serous cavity surrounding many abdominal organs.
Alimentary canal: mouth, pharynx, esophagus, stomach, small intestine, large intestine, anus.
Accessory organs: salivary glands, liver, gallbladder, pancreas.
Functions:- Alimentary functions: ingestion, nutrient absorption, waste elimination.
Accessory functions: production of digestive juices.
Digestive tract anatomy and functions:- Mouth: mechanical digestion.
Salivary glands: chemical digestion.
Pharynx and Esophagus: transport food.
Stomach: chemical and mechanical digestion.
Small intestine: nutrient absorption.
Large intestine: water absorption.
Appendix: immune functions.
Rectum: feces storage.
Liver: multiple metabolic and detoxification roles including bile production.
Pancreas: exocrine (digestive enzymes) and endocrine (insulin, glucagon).
Urinary System and Reproduction (Brief Overview)
Urinary system structures: kidneys, ureters, bladder, urethra.
Functions: filter and excrete wastes; regulate water and electrolyte balance; maintain acid-base balance.
Reproductive anatomy (overview): male structures include scrotum, testes, spermatic ducts, sex glands, penis; female structures include ovaries, fallopian tubes, uterus, vagina, vulva, mammary glands and breasts. Functions include production and transport of gametes and sex hormones.
Key Concepts and Formulas to Internalize
Cardiovascular and circulatory relations:- Cardiac Output:
Blood Pressure:
Normal adult heart rate range:
Respiratory physiology:- Minute volume:
Tidal volume (typical adult):
Ventilation is driven by pressure changes (negative pressure mechanism).
Alveolar-capillary gas exchange via diffusion; external respiration (lungs) and internal respiration (tissues).
Oxygen transport: Hb carries up to 4 O2 molecules per Hb; 1 O2 bound \approx 25% saturation; 4 O2 bound \approx 100% saturation.
CO2 transport: primarily carried as bicarbonate in plasma; exhaled as CO2.
Blood components and fluid balance:- Blood composition: ~45% formed elements (RBCs ~42–48%, WBCs, platelets) and ~55% plasma; plasma is ~91% water; plasma proteins include albumin and clotting factors.
Hydrostatic pressure pushes fluid out of capillaries; plasma oncotic pressure pulls fluid back in; balance maintains vascular volume and prevents edema; imbalances can cause edema or hypovolemia.
CNS and autonomic control:- Sympathetic vs. Parasympathetic balance controls many organ systems; epinephrine/norepinephrine mediate the sympathetic response.
Medullary centers regulate respiration and heart rate; pons regulates transition between inspiration and expiration.
The brain and spinal cord are protected by meninges and CSF.
Quick Reference: Common Terms and States
Anatomical positions and planes: sagittal/midsagittal, frontal/coronal, transverse/horizontal.
Body axes and directional terms: anterior vs. posterior; medial vs. lateral; proximal vs. distal; superior vs. inferior; plantar vs. palmar.
Abdominal anatomy quick facts: solid organs (bleed when injured) vs hollow organs (leak when perforated).
The “recovery position” is the left lateral recumbent position; used to maintain airway and drainage in unconscious patients when spinal injury is not suspected.
The mnemonic SAD PUCKER helps recall retroperitoneal organs to aid rapid assessment in emergencies.
Connection to Real-World Practice and Test Readiness
Emergency assessment requires quick recall of anatomy planes, body positions, organ locations, and physiologic principles (airway, breathing, circulation).
Recognize the signs of adequate vs. inadequate breathing and how tidal volume and rate affect gas exchange and oxygen delivery.
Use the known relationships in cardiovascular and respiratory physiology to anticipate patient status and necessary interventions (e.g., adjusting ventilation to optimize minute volume; recognizing edema as a sign of fluid balance issues or heart failure).
Be prepared to identify anatomical references in clinical scenarios, including retroperitoneal organs and the implications of abdominal organ injuries.
Practice Prompts Summary (from Transcript)
Forearm fracture location prompts: distal forearm fracture options (proximal, superior, dorsal, distal).
Anatomical relation questions: body parts closer to midline (medial) vs farther (lateral);
relation to chest (posterior vs anterior).
Skeletal anatomy queries: describe injuries as bilateral, unilateral, proximal, distal, etc. in context of limbs.
Test-style prompts emphasize understanding of anatomical directions, planes, and positions.
Ethical and Practical Implications
Emphasis on avoiding harm in patient handling (e.g., avoiding Trendelenburg or other shock positions when spinal injury is suspected).
Recognition that rapid, correct interpretation of anatomical and physiological knowledge can influence patient outcomes in emergencies.
Importance of precise terminology (to avoid miscommunication) and verification when needed (e.g., looking up unfamiliar terms).