Vital Signs, Body Structure and Function, and Common Diseases and Disorders

Measurement of Weight and Height

  • Clinical Objectives and Scheduling:

    • Weight and height are measured upon a client's admission to a facility or agency, and subsequently as directed by the care plan or physician orders.
    • Monitoring weight is essential for evaluating nutritional status, fluid retention, response to medical therapies, and medication dosing.

  • Scale Equipment:

    • Balance beam scales
    • Chair scales
    • Lift scales
    • Wheelchair weigh scales
    • Digital scales

  • Standardized Measurement Guidelines:

    • The client must wear only a gown or pyjamas during measurement to prevent excess clothing weight from skewing results.
    • The client must void before being weighed; if a routine or ordered urine specimen is needed, it must be collected at this time.
    • Weight measurements must be taken at the exact same time of day each time to maintain consistency across comparative data.
    • The identical scale must be utilized for all serial measurements (daily, weekly, and monthly weights).
    • The scale must always be balanced at zero (00) prior to weighing the client.
    • All weight measurements are recorded in kilograms (kg\text{kg}).

Vital Signs: Fundamentals, Assessment, and Monitoring

  • Physiological Significance:

    • Vital signs reflect the continuous function of three core bodily processes essential for human life:
      • Regulation of body temperature
      • Breathing (respiratory function)
      • Heart function (circulatory function)
    • A person's vital signs vary naturally within recognized physiological limits.
    • Vital signs are measured to detect changes in normal body function, monitor responses to medical treatment, identify early indicators of life-threatening events, and form an indispensable component of the clinical assessment process.
    • Vital signs demonstrate even minor variations in a client's physiological condition.

  • Core Vital Signs and Clinical Acronyms:

    • Temperature, Pulse, Respiration, Blood Pressure (TPR BP\text{TPR BP}; collectively abbreviated VS\text{VS}
    • Oxygen saturation (SpO2\text{SpO}_2): The measurement of peripheral capillary oxygen saturation is recognized by many agencies as a critical vital sign. Performing this assessment requires specialized institutional training. A normal reading is SpO2≥94%\text{SpO}_2 \ge 94\%.
    • Pain assessment: Scaled from 0 to 100\text{ to }10.
    • Diagnostic and clinical acronyms:
      • HIR\text{HIR}: Head Injury Routine
      • LOC\text{LOC}: Level of Consciousness
      • HTN\text{HTN}: High Blood Pressure (Hypertension)

  • Indications for Measuring Vital Signs:

    • During formal physical examinations.
    • Immediately upon admission to a facility.
    • As frequently as indicated by the client's medical condition.
    • Before and after surgical procedures, complex treatments, or diagnostic investigations.
    • Following specific care measures.
    • Immediately after a fall, trauma, or injury.
    • In long-term care (LTC\text{LTC}) environments, particularly when the client is prescribed cardiac medications.
    • Whenever medications are administered that affect the respiratory or circulatory systems.
    • Upon client complaints of pain, dizziness, light-headedness, faintness, shortness of breath, a rapid heart rate, or a general sense of not feeling well.
    • As established within the client's care plan or authorized by doctor's orders.
    • As directed following the administration of antipyretic medications given to relieve fever.

  • General Assessment and Reporting Rules:

    • Accuracy is critical during the measurement, documentation, and reporting of vital signs.
    • Unless an explicit clinical order specifies otherwise, all vital signs must be assessed with the client positioned in either a supine (lying) or sitting position.
    • The following findings must be reported to the supervising nurse immediately:
      • Any vital sign reading that has changed in comparison to previous baseline measurements.
      • Any vital sign value that registers above the established normal range.
      • Any vital sign value that registers below the established normal range.

Body Temperature Measurement

  • Thermoregulatory Balance:

    • Body temperature represents the physiological equilibrium maintained between the amount of heat generated by metabolic processes and the amount of heat dissipated to the external environment.

  • Measurement Sites and Instrumentation:

    • Thermometers are used to capture body temperature across several designated anatomic sites, each associated with specific normal ranges:
      • Mouth (oral site)
      • Rectum (rectal site)
      • Axilla (axillary site / armpit)
      • Tympanic membrane (aural / ear canal site)
    • Types of thermometers used in clinical practice:
      • Electronic thermometers: Battery-operated devices; specific designs feature specialized oral and rectal probes fitted with single-use disposable covers, or dedicated tympanic membrane configurations.
      • Dot matrix thermometers
      • Temperature-sensitive tape
      • Glass thermometers: Now rarely used due to their classification as hazardous instruments that present risk of mercury exposure or structural breakage.
    • Scope of Practice Restriction: Support workers are not authorized to measure rectal temperatures.

Pulse Assessment and Monitoring

  • Physiological Definition:

    • The pulse is the palpable rhythmic contraction and expansion of an artery, produced by the ejection of blood from the heart during ventricular contraction as a fluid wave passes through arterial walls.

  • Anatomical Pulse Sites (Bilateral):

    • Temporal pulse (sides of the forehead/temple)
    • Carotid pulse (neck, adjacent to the trachea; primary site during CPR and acute emergencies)
    • Brachial pulse (inner aspect of the antecubital fossa)
    • Radial pulse (wrist along the radial bone on the thumb side; the site used most frequently for routine assessment)
    • Femoral pulse (groin area along the femoral artery)
    • Popliteal pulse (posterior aspect of the knee)
    • Posterior tibial pulse (inner side of the ankle behind the medial malleolus)
    • Dorsalis pedis pulse / pedal pulse (top surface of the foot)
    • Apical pulse: Assessed directly over the heart apex via stethoscope auscultation.

  • Pulse Rate Parameters:

    • Pulse rate represents the exact number of heartbeats or arterial pulses palpable over the duration of 1 minute1\text{ minute}.
    • Rates fluctuate significantly by age group; a normal resting pulse rate in a healthy adult ranges between 60 and 100 beats per minute60\text{ and }100\text{ beats per minute}.
    • Abnormal parameters requiring immediate notification to the supervising nurse:
      • Tachycardia: A heart rate exceeding 100 beats per minute100\text{ beats per minute}.
      • Bradycardia: A heart rate falling below 60 beats per minute60\text{ beats per minute}.

  • Rhythm and Force Qualities:

    • Rhythm describes the spacing between beats, which should be regular and uniform.
      • An irregular pulse denotes uneven time intervals between pulsations or skipped beats.
    • Force reflects arterial pulse strength and stroke volume:
      • Forceful pulses are recorded as strong, full, or bounding.
      • Difficult-to-palpate pulses are documented as weak, thready, or feeble.
    • While automated electronic blood pressure devices are capable of tallying pulse counts, they cannot analyze rhythm or force. Palpation by hand is mandatory to evaluate qualitative pulse characteristics.

  • Pulse Oximeter Technology:

    • A pulse oximeter is an electronic optical device that continuously or intermittently monitors both pulse rate and blood oxygenation levels.
    • The sensor probe is positioned over the client's index finger.
    • The measurement is expressed as a percentage or peripheral capillary oxygen saturation (SpO2\text{SpO}_2).

Respiratory Function and Measurement

  • Measurement Guidelines:

    • Respirations must be counted exclusively when the client is at physical rest.
    • The health care provider must position themselves so the rise and fall of the client's thoracic cavity is clearly visible.
    • The client must remain unaware that respirations are being monitored, as conscious awareness alters natural breathing cadence and depth.
    • Respirations are counted immediately following radial pulse palpation without shifting hand or stethoscope placement.
    • The standard counting procedure requires tracking chest elevations for 30 seconds30\text{ seconds} and multiplying that tally by 22. If an irregular, abnormal, or questionable rhythm is observed, the respirations must be counted for an entire 60 seconds60\text{ seconds}.

  • Normal Respiratory Rates by Age Group:

    • Healthy adult rate: 12 to 20 respirations per minute12\text{ to }20\text{ respirations per minute}
    • Newborn: 30 to 60 respirations per minute30\text{ to }60\text{ respirations per minute}
    • Infant: 30 to 50 respirations per minute30\text{ to }50\text{ respirations per minute}
    • Toddler: 25 to 32 respirations per minute25\text{ to }32\text{ respirations per minute}
    • Child and preadolescent (3 to 12 years3\text{ to }12\text{ years}): 20 to 30 respirations per minute20\text{ to }30\text{ respirations per minute}
    • Adolescent (13 to 18 years13\text{ to }18\text{ years}): 16 to 19 respirations per minute16\text{ to }19\text{ respirations per minute}
    • Adult (>18 years> 18\text{ years}): 12 to 20 respirations per minute12\text{ to }20\text{ respirations per minute}

Blood Pressure Physiology and Measurement

  • Hemodynamic Principles:

    • Blood pressure (BP\text{BP}) represents the hydrostatic force exerted against arterial vascular walls by circulating blood.
    • Blood pressure dynamics are controlled by three factors:
      • The contractile force generated by the myocardium
      • The total volume of blood ejected with each cardiac cycle (stroke volume)
      • Peripheral vascular resistance (the relative ease or difficulty of blood flow through the vascular tree)

  • The Cardiac Cycle and Hemodynamics:

    • Right side of the heart: Receives deoxygenated (oxygen-poor) blood returning from systemic circulation and propels it into the pulmonary circuit to undergo oxygenation.
    • Left side of the heart: Receives oxygenated (oxygen-rich) blood returning from the pulmonary capillaries and ejects it under systemic pressure to the rest of the body.
    • Systole: The active mechanical contraction phase wherein ventricular chambers compress to forcefully expel blood into the systemic and pulmonary vascular circuits.
    • Diastole: The resting relaxation phase between heartbeats during which myocardial muscle fibres relax and the atrial and ventricular chambers fill with venous return blood.
    • Rest and work balance: The myocardium spends a significant proportion of each 24-hour cycle in diastolic rest between beats to maintain its continuous physiological rhythm.

  • Measurement Units and Reference Ranges:

    • Measured in millimetres of mercury (mm Hg\text{mm Hg}).
    • Recorded as a fraction: systolic pressure positioned over diastolic pressure.
    • Systolic blood pressure represents the arterial pressure generated during ventricular pumping.
    • Diastolic blood pressure represents the residual pressure persisting within arterial trees when the heart is at rest.
    • Normal reference limits:
      • Systolic pressure: 90 to 140 mm Hg90\text{ to }140\text{ mm Hg}
      • Diastolic pressure: 60 to 90 mm Hg60\text{ to }90\text{ mm Hg}
    • Normal healthy resting baseline: Strictly below 120/80 mm Hg120/80\text{ mm Hg}.

  • Hypertension and Hypotension:

    • Hypertension: A sustained, consistent blood pressure measurement exceeding 140/90 mm Hg140/90\text{ mm Hg}.
    • Hypotension: A blood pressure reading registering lower than 90/60 mm Hg90/60\text{ mm Hg}.
    • Immediate reporting criteria:
      • Any systolic measurement below 90 mm Hg90\text{ mm Hg} or above 140 mm Hg140\text{ mm Hg}
      • Any diastolic measurement at or above 90 mm Hg90\text{ mm Hg}
      • Any diastolic measurement below 60 mm Hg60\text{ mm Hg}

  • Instruments and Clinical Techniques:

    • Sphygmomanometer: Comprises an inflatable compression cuff and an analog or digital pressure meter. Models include aneroid, mercury, and electronic types.
    • Stethoscope: An acoustic device designed to auscultate internal sounds produced by the heart, lungs, and arterial vasculature. Must be cleansed thoroughly using antiseptic wipes across earpieces and diaphragm before and after every client encounter to prevent cross-transmission of micro-organisms.
    • Ausculatory procedure:
      • Cleanse earpieces and diaphragm with antiseptic wipes.
      • Warm the metallic diaphragm within the hand before applying it to the client's skin.
      • Position earpiece tips directed forward in line with the external auditory canal.
      • Place the diaphragm directly over the palpated brachial artery and hold it securely.
      • Ensure a completely silent environment to accurately detect Korotkoff sounds.
    • Delegation prerequisites for support workers:
      • Explicit authorization by the employer.
      • Presence of the procedure in the formal job description.
      • Completion of accredited training.
      • Supervised procedural review performed with a registered nurse.
      • Continuous nurse availability for ongoing supervision.
    • Clinical contraindications: Blood pressure must not be measured on an arm on the side of a previous mastectomy or where specific clinical conditions dictate contraindication.

Support Worker Practices and Communicable Disease Care

  • Psychosocial Dynamics:

    • Clients diagnosed with communicable infections frequently experience intense psychological responses, including emotional shock, acute embarrassment, fear of social stigma, and anger regarding transmission origin.

  • Standard Protective Procedures:

    • Don all recommended personal protective equipment (PPE\text{PPE}) designated in the individualized client care plan.
    • Maintain adherence to Standard Practices at all times during client interactions.
    • Change out of work uniforms completely prior to leaving the facility or the client's domestic environment to prevent disseminating pathogens into community settings.
    • Communicate with active listening and genuine empathy, confirming dignity and respect.
    • Strictly preserve confidentiality; never discuss client behaviours, personal histories, or conditions that contributed to pathogen exposure.
    • Deliver all care within an objective, completely non-judgmental framework.

Body Structure and Function: Organization, Tissues, and Homeostasis

  • Foundational Anatomical Definitions:

    • Anatomy: The formal scientific study of body structures and spatial relationships.
    • Physiology: The study of the biological mechanisms and functional processes of living structures.
    • Anatomical position: The universal descriptive reference position wherein the human body stands erect, facing directly forward, arms down at sides with palms turned forward.

  • Biological Hierarchy:

    • Cell: The microscopic foundational unit of all living structures.
    • Tissues: Groups of specialized cells possessing similar morphology and unified functions.
    • Organs: Complex structures composed of multiple tissue types integrated to execute specific actions.
    • Organ systems: Ensembles of coordinated organs operating collectively to carry out complex biological functions.
    • Homeostasis: The physiological steady state characterized by an internal environment maintained through coordinated negative and positive organ system feedbacks (for example, cutaneous shivering stimulated by falling ambient temperatures to generate metabolic heat).

  • The Four Primary Tissue Classes:

    • Epithelial tissue: Covers external surfaces of the body and forms linings over internal hollow cavities, organs, and lumina.
    • Connective tissue: Structurally anchors, interconnects, protects, and supports adjacent body tissues and structures.
    • Muscle tissue: Specialized contractile tissue capable of shortening and elongating to produce skeletal movement and mechanical force.
    • Nerve tissue: Excitable tissue that generates, receives, and propagates electrical electrochemical impulses connecting the brain to the peripheral anatomy.

Musculoskeletal Anatomy and Physiology

  • Structural Mechanics and Skeletal Organization:

    • Composed of 206 bones206\text{ bones}, associated skeletal muscles, ligaments, tendons, and articular cartilage.
    • Provides external structural form, protects internal viscera, facilitates mechanical locomotion, stores minerals, and houses haematopoietic tissue.
    • Haematopoiesis: Blood cell formation occurs within internal red bone marrow.

  • Bone Classifications:

    • Long bones: Cylindrical elongated shafts that support systemic body weight (e.g., femur, humerus).
    • Short bones: Cuboidal structures that facilitate precision movements and ease of locomotion.
      • Carpal bones of the wrist: Scaphoid, lunate, capitate, hamate, triquetrum, pisiform, trapezoid, trapezium.
      • Tarsal bones of the ankle: Talus, calcaneus, navicular, cuboid, cuneiforms.
    • Flat bones: Broad thin plates designed to shelter internal vital organs (e.g., cranial bones, ribs, sternum).
    • Irregular bones: Complex structural geometries that permit variable articulation and flexible movement (e.g., vertebrae).
    • Sesamoid bones: Small, rounded bones embedded within tendons to mitigate compressive friction and shield tendon fibers from excessive mechanical wear (e.g., patella).

  • Articular Joint Classifications:

    • A joint represents the functional junction where two or more bones meet.
    • Ball-and-socket joints: Permit multi-axial movement across all rotational directions (e.g., glenohumeral hip and shoulder joints).
    • Hinge joints: Uniaxial systems permitting motion in a single plane (e.g., elbow, knee).
    • Pivot joints: Uniaxial structures permitting rotational turning from side to side (e.g., atlantoaxial joint).
    • Saddle joints: Biaxial configurations granting extensive ranges of movement (e.g., carpometacarpal joint of the thumb).
    • Gliding joints: Planar surfaces permitting limited, smooth multidirectional sliding movements.
    • Condyloid joints: Biaxial articulations where an oval convex articular head seats into an elliptical concavity (e.g., radiocarpal wrist joint, metacarpophalangeal knuckle joints).

  • Muscular Histology and Functions:

    • The body possesses upwards of 600 muscles600\text{ muscles}.
    • Primary physiological functions:
      • Mechanical movement of external and internal body parts
      • Maintenance of skeletal posture and stability
      • Thermogenesis (generation of body heat via metabolic contraction)
    • Muscle varieties:
      • Skeletal muscle: Striated in appearance, attached securely to osseous structures, and controlled via conscious voluntary neural pathways.
      • Smooth muscle: Non-striated, involuntary tissue located within hollow visceral organs, including the stomach, intestines, urinary bladder, and arterial walls.
      • Cardiac muscle: Located exclusively within the myocardium; exhibits microscopic striations similar to skeletal muscle but operates entirely via involuntary pacemakers.

Nervous System and Special Sense Organs

  • Central Nervous System (CNS):

    • Coordinates, monitors, and directs global bodily functions; comprised of the brain and the spinal cord.
    • The brain is protected by the cranium and divided into three structural components:
      • Cerebrum: Mediates high-level executive thinking, sensory perception, and voluntary motor action.
      • Cerebellum: Regulates fine motor coordination, posture, and motor balance.
      • Brainstem: Houses vital involuntary autonomic centers that control cardiac output, vascular tone, and respiratory drive.
    • Spinal cord: Situated within the vertebral canal; contains ascending sensory and descending motor pathways.
    • Meninges: Three distinct connective tissue membranes that envelop and cushion the brain and spinal cord:
      • Dura mater: Tough, fibrous outer layer lying immediately adjacent to cranial bone.
      • Arachnoid mater: Web-like intermediate vascular layer.
      • Pia mater: Delicate, highly vascularized internal layer bound directly to neural parenchyma.

  • Peripheral Nervous System (PNS):

    • Extends throughout all peripheral tissues beyond the central axis.
    • 12 pairs12\text{ pairs} of cranial nerves: Conduct sensory and motor impulses directly between the brain and anatomical regions of the head, neck, thorax, and abdomen.
    • 31 pairs31\text{ pairs} of spinal nerves: Conduct sensory and motor signals to and from the cutaneous skin, extremities, and thoracic/abdominal visceral structures.

  • Sensory Receptors:

    • Gustation (Taste): Mediated by taste buds embedded within tongue papillae, responding to four primary sensations: sweet, sour, salty, and bitter.
    • Olfaction (Smell): Mediated by specialized olfactory receptors situated in the roof of the nasal cavity; functionally interconnected with gustatory perception.
    • Tactile sensation (Touch): Mediated by dermal mechanoreceptors concentrated densely within the lips, fingertips, and toes.
    • Vision (The Eye): Houses specialized photoreceptors across three concentric structural layers:
      • Sclera: Fibrous white protective outer tunic.
      • Choroid: Pigmented vascular middle tunic supplying blood flow.
      • Retina: Photosensitive inner tunic containing rods and cones that convert light into visual neural impulses.
    • Auditory and Equilibrium (The Ear):
      • External ear: Formed by the pinna (auricle) and external acoustic meatus, bounded medially by the tympanic membrane (eardrum).
      • Middle ear: Air-filled cavity connected to the nasopharynx by the Eustachian tube; contains three auditory ossicles (malleus, incus, and stapes) that mechanically amplify vibrations.
      • Inner ear: Fluid-filled sensory labyrinth composed of the snail-shaped cochlea (transmitting sound wave impulses to the auditory cranial nerve) and three semicircular canals (mediating vestibular balance and spatial orientation).

Endocrine System Anatomy and Hormone Regulation

  • Glandular Mechanism:

    • Composed of ductless endocrine glands that synthesize and secrete specialized biochemical messengers (hormones) directly into the systemic bloodstream to regulate target organ metabolism.

  • Primary Endocrine Structures and Hormones:

    • Pituitary Gland: Known as the master endocrine gland; situated at the base of the brain behind the optic chiasm.
      • Anterior lobe: Secretes Growth Hormone (GH\text{GH} , Thyroid-Stimulating Hormone (TSH\text{TSH} , Adrenocorticotropic Hormone (ACTH\text{ACTH} , and gonadotropic hormones regulating male and female reproductive organs.
      • Posterior lobe: Secretes Antidiuretic Hormone (ADH\text{ADH} , which regulates renal fluid retention, and Oxytocin, which stimulates smooth muscle uterine contractions.
    • Thyroid Gland: Situated along the anterior neck inferior to the larynx; synthesizes thyroid hormones—triiodothyronine (T3T_3) and thyroxine (T4T_4)—to govern metabolic rates, along with calcitonin for calcium regulation.
    • Parathyroid Glands: Four miniature glands embedded in pairs along the posterior lobes of the thyroid; secrete parathormone to regulate systemic calcium homeostasis.
    • Adrenal Glands: Paired pyramidal structures situated above the superior pole of each kidney:
      • Adrenal medulla: Secretes catecholamines (epinephrine and norepinephrine) mediating acute sympathetic fight-or-flight responses.
      • Adrenal cortex: Synthesizes three classes of steroid hormones necessary for survival: glucocorticoids, mineralocorticoids, and small amounts of sex steroids.
    • Pancreas: Specialized endocrine islets secrete insulin to clear glucose from the bloodstream into cells.
    • Gonads: Testes in males secrete testosterone; ovaries in females secrete estrogen and progesterone.

Communicable Diseases and Immunology

  • Transmission Vectors and Pathogen Exposure:

    • Communicable diseases are infectious conditions triggered by micro-organisms that spread among human populations.
    • Modes of transmission:
      • Direct contact
      • Indirect contact
      • Airborne transmission
      • Vehicle transmission
      • Vector transmission
    • Biological outcomes following pathogen exposure:
      • The host immune response neutralizes and eliminates the pathogen immediately.
      • The pathogen survives without causing clinical disease.
      • The pathogen proliferates and precipitates active clinical infection.

  • Immunization and Pandemics:

    • Vaccination serves as an evidence-based preventative intervention that prevents communicable infections from developing into life-threatening pathology.
    • Pandemic: An infectious disease outbreak that rapidly sweeps across national borders or expands worldwide.
    • Mandated or recommended vaccinations for health care personnel:
      • Annual influenza vaccination
      • Hepatitis B immunization series
      • Hepatitis A immunization
      • Baseline and routine tuberculin (TB\text{TB}) skin testing

  • COVID-19:

    • High-consequence respiratory communicable illness spread via respiratory droplets among people in close proximity (<2 m< 2\text{ m} or 6 ft6\text{ ft}).
    • Pathological sequelae: Multisystem organ injury involving the myocardium, pulmonary parenchyma, and central nervous tissue; thrombotic events within the vascular tree; persistent chronic fatigue; and mood alterations.

  • Viral Hepatitis:

    • Inflammatory pathology of the liver presenting in acute or chronic forms.
    • Acute hepatitis manifestations (often resolving within 1 to 2 months1\text{ to }2\text{ months}): Dark-coloured urine, cutaneous jaundice (developing after approximately 2 weeks2\text{ weeks} in some clients), acholic (light-coloured) stools, myalgia, arthralgia, drowsiness, irritability, cutaneous pruritus, and diarrhea.
    • Hepatitis A (HAV\text{HAV}): Spread through the fecal-oral route; associated with contaminated food, poor sanitation, overcrowding, and inadequate hygiene. Does not lead to chronic hepatitis.
    • Hepatitis B (HBV\text{HBV}) and Hepatitis C (HCV\text{HCV}): Blood-borne pathogens transmitted through parenteral exposure, shared needles, accidental needlesticks, and unprotected sexual intercourse. Both carry infectious potentials far higher than HIV and can progress to permanent chronic hepatitis, cirrhosis, and hepatic failure. Hepatitis B is preventable via routine immunization provided free to children and select adult demographics in Canada.

  • Herpes Simplex Viruses:

    • HSV-1 (Oral herpes): Typically presents as cold sores or fever blisters along facial perioral distributions above the waist.
    • HSV-2 (Genital herpes): Typically presents as painful ulcerations across the genitalia and perianal anatomy below the waist.
    • Both viral strains can cross-infect anatomical sites through oral-genital contact.
    • Symptoms arise between 3 days and 1 week3\text{ days and }1\text{ week} post-exposure, often preceded by prodromal tingling, fever, localized burning, and malaise.

  • Sexually Transmitted Infections (STIs):

    • Transmitted via sexual activity; frequently present asymptomatically, leading to undiagnosed transmission.
    • Lesions can manifest across the genital tract, rectum, mouth, throat, eyes, ears, and cutaneous breaks.
    • Barrier protection (condoms) and Standard Practices are necessary to halt transmission.

Oncology: Pathophysiology, Classification, and Interventions

  • Neoplasia and Cell Proliferation:

    • Normal tissue repair is governed by controlled cell division; cancer is characterized by uncontrolled cellular replication forming an abnormal mass (tumour).
    • Benign tumours: Non-cancerous masses that expand slowly, remain encapsulated, do not invade regional tissue, do not metastasize, and rarely present fatal risks.
    • Malignant tumours: Aggressive neoplastic growths that invade adjacent structures, destroy normal tissue architecture, access vascular/lymphatic channels to metastasize, and are potentially fatal.
    • Metastasis: The dissemination of malignant cells from a primary tumour site to distant anatomical locations where secondary tumours establish.

  • Epidemiological Risk Factors and Warning Signs:

    • Common malignancies: Breast cancer is the most prevalent female cancer (representing 1 in 41\text{ in }4 Canadian female cancer diagnoses in 2020); prostate cancer is the most common malignancy in men.
    • Etiological factors: Genetic predisposition, tobacco use, alcohol abuse, diets high in fats and calories but deficient in dietary fibre, ionizing radiation (including solar ultraviolet exposure), occupational carcinogens, exogenous hormones, and oncogenic viruses.

  • Treatment Modalities:

    • Goals of oncology care: Total cure (commonly achievable in stages 0 to 20\text{ to }2), containment to prevent systemic spread, or palliative relief of secondary symptoms.
    • Surgical excision: Resection of neoplastic tissue to eliminate tumours or decompress adjacent pain-generating structures.
    • Radiation therapy (Radiotherapy): Ionizing radiation used to destroy tumours, downsize lesions preoperatively, eradicate microscopic margins postoperatively, or relieve pain.
    • Chemotherapy: Cytotoxic pharmacological agents administered orally or intravenously to disrupt cellular replication. Because chemotherapy destroys rapidly dividing healthy cells alongside malignant ones, adverse effects are severe: gastrointestinal mucosal irritation (nausea, vomiting, intractable diarrhea), stomatitis (oral ulcerations), and alopecia (hair loss).
    • Stem-cell transplantation: Reconstitution of haematopoietic marrow using autologous or allogeneic bone marrow or umbilical cord blood.
    • Supportive care priorities: Systematic pain management, nutritional support, prevention of cutaneous skin breakdown, management of treatment-related side effects, and psychosocial support.

Integumentary System Pathology

  • Dermatological Cancers:

    • Malignant growths originating within epidermal tissue.
    • Basal cell carcinoma and squamous cell carcinoma represent the two most common skin cancers.
    • Malignant melanoma is an aggressive, potentially fatal melanocytic malignancy if not caught early.
    • Melanoma signs:
      • Asymmetry
      • Irregular, scalloped, or jagged borders
      • Colour variegation (black, brown, blue, pink, white)
      • Surface pruritus, texturing shifts, ulceration, oozing, or bleeding

  • Infectious and Inflammatory Skin Disorders:

    • Athlete's Foot (Tinea pedis): Contagious superficial fungal infection causing erythema, burning, scaling, and pruritus of the feet; managed with over-the-counter (OTC\text{OTC}) antifungals.
    • Boil (Furuncle): Acute, painful, purulent staphylococcal infection of a hair follicle localized to the back, underarms, shoulders, thighs, or buttocks; requires Standard Precautions due to drainage risk.
    • Cyst: Closed epithelialized sac containing fluid, air, or semi-solid material that persists indefinitely unless surgically excised or medically resolved.
    • Dermatitis: Direct cutaneous inflammation caused by irritants (soaps, harsh chemicals, mimicking chemical burns) or allergens (contact dermatitis).
    • Eczema: Inflammatory pruritic dermatosis characterized by erythema, papules, vesicular weeping, and dry skin; managed with emollient creams to maintain hydration.
    • Impetigo: Superficial, contagious bacterial infection caused by Staphylococcus or Streptococcus; characterized by scratching that spreads pathogens, forming crusts; managed via topical or systemic antibiotics.
    • Psoriasis: Chronic autoimmune condition characterized by hyperproliferative epidermal turnover, presenting as silvery, scaly plaques over inflamed skin; exacerbated by stress and alcohol.
    • Scabies: Contagious parasitic dermatosis caused by Sarcoptes scabiei mites burrowing beneath the stratum corneum to deposit ova; produces intense pruritus, spreads via skin contact, remains undiagnosed for over a month, and requires topical antiparasitics.
    • Scleroderma: Progressive autoimmune disease leading to excessive collagen accumulation and hardening of cutaneous and connective tissues; classified into localized and generalized forms.
    • Seborrheic Keratosis: Benign, pigmented, verrucous epidermal growths commonly observed in older adults that can resemble melanocytic nevi.
    • Shingles (Herpes Zoster): Painful reactivation of latent varicella-zoster virus within sensory nerve pathways; causes unilateral dermatomal vesicular eruptions persisting roughly 2 weeks2\text{ weeks}, associated with debilitating neuralgia; necessitates personal protective equipment (PPE\text{PPE}) during active shedding.
    • Skin Tags: Harmless pedunculated cutaneous outgrowths common in older persons and females, prone to mechanical friction from apparel.
    • Urticaria (Hives): Acute hypersensitivity reaction producing raised, edematous, pruritic wheals in response to allergens such as medications or shellfish.

Musculoskeletal Disorders and Rehabilitative Care

  • Fractures and Bone Healing:

    • Closed (Simple) fracture: Osseous structural disruption where the bone breaks without breaching the skin barrier.
    • Open (Compound) fracture: The fractured bone pierces through the cutaneous skin, creating an open wound with a high risk of osteomyelitis.
    • Etiological factors: Mechanical falls, motor vehicle accidents, primary or secondary osseous neoplasms, alcoholism, and osteoporosis.
    • Clinical signs: Structural deformity, acute localized pain, edema, loss of mechanical function, hematoma formation, and internal or external hemorrhage.
    • Fracture realignment (Reduction):
      • Closed reduction: External manipulation without surgical incision.
      • Open reduction: Surgical incision with internal fixation hardware (pins, screws, plates, wires, rods).
    • Casting and Immobilization: Plaster, fiberglass, or plastic molds applied to maintain anatomical alignment. Plaster requires 24 to 48 hours24\text{ to }48\text{ hours} to dry completely, becoming white, odorless, and rigid. Support personnel must monitor for neurovascular compromise and report numbness, coldness, or tingling immediately.
    • Traction systems:
      • Skeletal traction: Continuous mechanical pulling forces exerted via surgical pins, wires, or screws installed into bone tissue; applied in pelvic or femur fractures.
      • Skin traction: Temporary pre-operative stabilization using splints, bandages, or boots attached to the skin using lighter weights.

  • Hip Fractures and Complications in Older Adults:

    • Common among older women.
    • Classical presentation: Shortening of the affected leg accompanied by external (outward) rotation.
    • Postoperative complications: Pneumonia, urinary tract infections, deep vein thrombosis (DVT\text{DVT} ), pulmonary embolism, pressure ulcers, constipation, and delirium.
    • Surgical intervention: Fixation using internal hardware or hemi/total arthroplasty (hip replacement).

  • Osteomyelitis:

    • Infection of bone and marrow, commonly triggered by Staphylococcus bacteria entering via compound fractures or orthopaedic operations.
    • Manifests as severe localized bone pain, erythema, purulent drainage, high fever, and malaise.

  • Amputations, Gangrene, and Prosthetics:

    • Surgical removal of an extremity is most frequently performed due to peripheral vascular disease resulting from diabetes mellitus.
    • Gangrene: Necrosis of tissue caused by ischemia, thermal injury, or severe bacterial infection; requires debridement or surgical amputation to prevent fatal sepsis.
    • Prostheses: Artificial structural appliances fitted by physiotherapists and occupational therapists to replace missing limbs.
    • Phantom limb pain: Sensation of pain perceived as arising from the missing, amputated extremity; believed to stem from continuous irritation of severed nerve endings within the residual stump.
    • Stump skin care: Because the enclosed prosthetic socket traps perspiration, residual skin becomes warm and moist, predisposing the client to blisters, friction abrasions, and skin infections. Redness, edema, drainage, or pain must be reported immediately.

  • Osteoporosis:

    • Metabolic bone disease marked by reduced bone mineral density, porous trabeculae, and skeletal fragility, predisposing to fractures of the spine, hip, and wrist.
    • Risk factors: Estrogen deficiency, dietary calcium deficiencies, smoking, alcohol abuse, physical inactivity, and extended bed rest.
    • Prevention: Adequate dietary calcium and vitamin intake alongside consistent weight-bearing activities (walking, jogging, stair climbing).

  • Arthritic Joint Disorders:

    • Osteoarthritis (OA\text{OA}): Degenerative non-inflammatory joint disease characterized by progressive wear of articular cartilage, leading to bone-on-bone friction and osteophyte (bone spur) formation. The most common joint disorder, affecting approximately 80% of Canadians by age 7580\%\text{ of Canadians by age }75. Primarily impacts weight-bearing articulations (hips, knees, ankles, spine). Pain worsens as the day progresses and is exacerbated by cold, damp climates. Managed with analgesics (e.g., acetaminophen), weight reduction, range-of-motion (ROM\text{ROM}) exercises, assistive ambulation devices, and elevated toilet seats.
    • Rheumatoid Arthritis (RA\text{RA}): Systemic autoimmune disease triggering destructive inflammation of synovial membranes and connective tissues. Affects 1 in 6 Canadians aged 16 and older1\text{ in }6\text{ Canadians aged }16\text{ and older}, occurring more frequently in women between 25 and 50 years of age25\text{ and }50\text{ years of age}. Characterized by bilateral, symmetrical joint involvement starting in the small joints of the hands and feet before progressing systemically to heart, lung, and renal tissues. Pain and joint stiffness are worst in the morning and improve with activity throughout the day. Progressive pannus formation causes severe joint deformities.
    • Gout: Metabolic form of arthritis triggered by hyperuricemia, leading to the deposition of monosodium urate crystals within articular cartilage and surrounding synovial tendons. Most frequently targets the first metatarsophalangeal joint (the big toe), causing acute swelling, erythema, warmth, and intense pain.
    • Fibromyalgia: Chronic non-articular musculoskeletal pain syndrome characterized by diffuse aching, stiffness, localized tender points, chronic sleep disturbance, and fatigue.

Neurological Disorders and Traumatic Injuries

  • Epilepsy and Seizures:

    • Chronic neurological disorder characterized by recurrent, unprovoked paroxysmal seizures caused by abnormal, excessive electrical discharges in the brain.
    • Etiology: Perinatal hypoxia, head trauma, CNS infections (meningitis, encephalitis), metabolic toxicities, fever, cerebrovascular accidents, or intracranial neoplasms.
    • Clinical course: Seizures may be preceded by a sensory aura. Clinical management requires pharmacological anticonvulsants.
    • Care during a seizure: Prevent physical injury, cushion the head, clear surrounding obstacles, do not force objects into the mouth, and turn the individual onto their side into the recovery position to prevent airway obstruction and asphyxiation.

  • Cerebrovascular Accident (Stroke / CVA):

    • Interruption of blood flow to cerebral parenchyma secondary to vascular occlusion (ischemic stroke) or vascular rupture (hemorrhagic stroke); represents the fourth leading cause of mortality in Canada and a primary cause of adult neurological disability.
    • Transient Ischemic Attack (TIA\text{TIA}): Brief, temporary neurological deficits caused by transient cerebral ischemia that resolve quickly but serve as critical warning indicators for impending full stroke.
    • Risk factors: Age (>65 years> 65\text{ years}), male sex, chronic hypertension, diabetes mellitus, hypercholesterolemia, tobacco smoking, cardiovascular disease, sedentary lifestyle, and high alcohol consumption.
    • Clinical presentation: Sudden unilateral hemiplegia (paralysis of one side of the body), facial droop, sudden expressive/receptive aphasia, sudden monocular visual loss, severe thunderclap headache, vertigo, and loss of motor coordination.

  • Aneurysms:

    • Abnormal focal dilation and structural attenuation of an arterial wall or cardiac chamber; commonly located along the aorta or within the Circle of Willis inside the brain.
    • Cerebral aneurysm rupture triggers subarachnoid hemorrhage, stroke, permanent neurological devastation, or death.
    • Rupture symptoms: Abrupt, excruciating headache, acute nuchal rigidity (neck stiffness), emesis, photophobia, seizures, and loss of consciousness.

  • Acquired Brain Injury (ABI):

    • Damage to cerebral tissue precipitated by physical trauma, hypoxia, falls, or motor vehicle accidents (the leading cause of ABI in individuals under 40 years40\text{ years}).
    • Sequelae: Cognitive deficits (impaired attention, amnesia, executive dysfunction), physical changes (ataxic gait, vertigo, visual disturbances, sensory loss), and behavioural changes (depression, emotional lability, loss of impulse control).

  • Neurodegenerative Diseases:

    • Parkinson's Disease: Chronic, progressive movement disorder linked to dopamine depletion within basal ganglia nuclei, typically presenting past 50 years of age50\text{ years of age}. Clinical tetrad: Resting pill-rolling tremors, muscular rigidity, bradykinesia (slowed movements), postural instability with a stooped gait, and a blank, mask-like facial expression.
    • Huntington's Disease: Autosomal dominant genetic disorder causing striatal neuronal death, typically presenting between 20 and 60 years of age20\text{ and }60\text{ years of age}. Leads to uncontrolled choreiform movements, progressive dementia, emotional lability, and loss of basic activities of daily living (ADLs\text{ADLs} ).
    • Multiple Sclerosis (MS\text{MS}): Autoimmune demyelinating disease of the central nervous system wherein myelin sheaths insulating brain and spinal cord axons are destroyed. Canada demonstrates one of the highest global prevalence rates. Onset typically occurs between 15 and 40 years of age15\text{ and }40\text{ years of age}, predominantly targeting women. Features episodic relapses and remissions producing visual disturbances, paraparesis, sensory paresthesias, ataxia, speech difficulties, and neurogenic bowel/bladder dysfunction.
    • Amyotrophic Lateral Sclerosis (ALS\text{ALS} / Lou Gehrig's Disease): Fatal motor neuron disease attacking upper and lower motor neurons governing voluntary muscles, typically presenting between 40 and 70 years of age40\text{ and }70\text{ years of age} (affecting approximately 3000 Canadians3000\text{ Canadians}). Leads to progressive muscular atrophy starting distally in the hands before eliminating ambulation, swallowing, and breathing. Sensory and cognitive capabilities remain completely intact throughout the disease course.

  • Spinal Cord Injuries:

    • Traumatic disruption of spinal cord conduction pathways commonly caused by motor vehicle collisions.
    • Paraplegia: Loss of motor and sensory function involving the lower extremities and trunk, caused by thoracic, lumbar, or sacral cord lesions.
    • Quadriplegia (Tetraplegia): Complete functional loss spanning all four extremities, trunk, and respiratory musculature, resulting from cervical spinal cord lesions.

Endocrine System Disorders

  • Diabetes Mellitus Pathophysiology:

    • Metabolic disorder characterized by absolute deficiency of pancreatic insulin production or cellular resistance to insulin action, leading to persistent hyperglycemia.
    • Over 9 million Canadians9\text{ million Canadians} live with diabetes or pre-diabetes, with higher prevalence documented across Indigenous populations.
    • Classifications:
      • Type 1 Diabetes: Autoimmune destruction of pancreatic beta cells resulting in little to no insulin synthesis; accounts for roughly 10% of cases10\%\text{ of cases}, typically emerging in children, teenagers, and young adults; requires lifelong exogenous insulin administration.
      • Type 2 Diabetes: Peripheral insulin resistance combined with progressive secretory deficits; represents the most common form, typically occurring in individuals over 40 years of age40\text{ years of age}, with obesity, sedentary lifestyle, and hypertension serving as primary risk factors; managed via lifestyle modifications, oral antihyperglycemic medications, and supplemental insulin.
      • Gestational Diabetes: Glucose intolerance developing during pregnancy, resolving post-partum, but predisposing the mother to future Type 2 diabetes.
    • Cardinal symptoms: Polydipsia (increased thirst), polyuria (frequent urination), polyphagia (constant hunger), sudden unexplained weight loss, generalized fatigue, pruritic skin, and blurred vision.
    • Chronic microvascular and macrovascular complications: Retinopathy (leading to blindness), nephropathy (renal failure), peripheral neuropathy, sexual dysfunction, cardiovascular disease, stroke, peripheral vascular disease, and impaired wound healing leading to lower-extremity amputations.
    • Clinical monitoring: Daily capillary blood glucose monitoring (3 to 4 times per day3\text{ to }4\text{ times per day}) to track for hypoglycemia (abnormally low blood glucose) and hyperglycemia (abnormally high blood glucose).

  • Thyroid Pathologies:

    • Hyperthyroidism: Excessive synthesis and secretion of thyroid hormones (T3T_3 and T4T_4) causing an elevated metabolic rate. Manifestations include rapid weight loss, hyperphagia, physical hyperactivity, tachycardia, cardiac palpitations, heat intolerance, diarrhea, irritability, and emotional lability. Medical management involves surgical thyroidectomy or radioiodine (131I^{131}\text{I}) ablation.
    • Hypothyroidism: Insufficient production of thyroid hormones resulting in a generalized deceleration of systemic metabolic activity. Manifestations include weight gain, fatigue, mental lethargy, impaired memory, cold intolerance, chronic constipation, and bradycardia. Managed medically via lifelong synthetic thyroid hormone replacement.