What is an Emergency Medical System (EMS)?
A coordinated network of resources (personnel, vehicles, dispatch, communications, hospitals, medical direction, training, public education) that provides out-of-hospital acute medical care and transport to definitive care. Purpose: rapid access (911), on-scene stabilization, safe transport, and continuity of care.
Medical Director — role & relationships
• Role: Physician responsible for clinical oversight of the EMS system: sets clinical protocols, approves standing orders, provides medical oversight, quality assurance, training standards, and on-line/off-line medical direction. • Relationship with state EMS agency: The state EMS agency defines legal/regulatory framework (licensing, scope of practice, certification standards). The medical director operates within that framework and may advise the agency; the state agency has regulatory authority. • Relationship with EMT: The medical director provides medical oversight, sets protocols and standing orders EMTs follow, approves training/competency, and provides medical direction (on-line/off-line). • Who establishes scope of practice? The state EMS agency (or legislation/regulations) legally defines the EMT’s scope of practice. The medical director defines local protocols and medical practice within that legal scope.
On-line vs Off-line medical direction
• Off-line medical direction (a): Also called standing orders or protocols — written guidelines that allow EMTs to provide specified care without contacting a physician each time. Examples: treatment algorithms, drug administration rules. • On-line medical direction (b): Real-time direct physician contact (radio/phone/telemedicine) for orders/consultation when situations fall outside standing orders or require physician authorization.
Direct vs Indirect contact with an infectious substance
• Direct contact (a): Pathogen transfers directly from an infected person or reservoir to a susceptible person (e.g., blood-to-blood contact, kissing, touching an open wound). • Indirect contact (b): Transfer via an intermediate object or vector (fomite like contaminated equipment, needles, or via a surface), or through an intermediate host/vector (e.g., mosquito).
Transmission pathways
• Airborne (a): Small droplets/aerosols suspended in air that can be inhaled (e.g., TB, measles, varicella). • Bloodborne (b): Spread through infected blood or bodily fluids (e.g., HIV, hepatitis B/C) via percutaneous injury, mucous-membrane exposure. • Vectorborne (c): Transmitted by an organism that carries the pathogen between hosts (e.g., mosquitoes transmit malaria, ticks transmit Lyme). • Foodborne (d): Transmission by ingestion of contaminated food or water (e.g., Salmonella, E. coli).
Medical-legal terms
• Standard of care (a): The level and type of care that a reasonably competent and skilled health professional, with similar training and in the same community, would provide under similar circumstances. • Scope of practice (b): The actions and procedures a licensed/certified provider is legally permitted to perform, defined by law/regulation and agency/medical director protocols. • Duty to act (c): Legal obligation for certain persons (e.g., on-duty EMTs) to provide care. If on duty or summoned, failure may lead to legal liability.
When may an EMT decline CPR? What if in doubt?
EMT may decline or discontinue CPR when: • Valid DNR/advance directive or Physician/State-approved standing order exists. • Obvious signs of irreversible death (rigor mortis, decomposition, dependent lividity, decapitation, hemicorporectomy). • Clear evidence of a valid do-not-resuscitate order per local policy. • When rescuer safety cannot be assured. If conditions are in doubt: Begin resuscitation (CPR) and request on-line medical direction; treat until a valid DNR is produced or a physician confirms termination.
Informed consent vs expressed consent
• Informed consent: Patient receives explanation of diagnosis, recommended treatment, risks, benefits, and alternatives, and then voluntarily agrees. Requires decision-making capacity (alert, oriented, understands, not impaired). • Expressed consent: Patient explicitly agrees verbally or by action to receive care (e.g., says “OK, treat me”). Usually used in routine/emergency care when patient is competent. • Who can give informed consent: Competent adults and legally authorized decision-makers (e.g., guardians). • Who cannot: Unconscious patients, those who lack capacity (confused, intoxicated, severe cognitive impairment) — in these cases, implied consent applies for emergency care.
Communication tactics & rapport
• Convincing skeptical patient: Use calm tone, simple clear explanations, explain risks of refusing, describe benefits, offer choices, involve family if patient agrees, document refusal. If life-threatening and patient lacks capacity, treat under implied consent. • Rapport with frightened patient: Introduce yourself, explain what you will do step-by-step, maintain eye contact, offer reassurance, use simple language, keep actions gentle and deliberate. • With a child: Get on their level physically, use simple concrete words, allow a trusted adult present, give choices (when possible) to give a sense of control, use distraction and praise. • With an elderly patient: Speak clearly, a bit slower, use respectful tone, check for hearing/vision problems, involve family/caregiver, ask open questions and allow time to respond.
Open-ended vs closed-ended questions
• Open-ended (a): Invite explanation and narrative (e.g., “Tell me what happened,” “How are you feeling?”). Useful for gathering history. • Closed-ended (b): Yield short specific answers (yes/no or one detail) (e.g., “Are you short of breath?” “When did the pain start?”). Useful for focused assessment.
Medical terminology — body positions
• Prone (a): Lying face down. • Supine (b): Lying on back, face up. • Fowler’s (c): Semi-sitting position (head elevated 45–60°); used to assist breathing. • Lateral recumbent (d): Side-lying position (recovery position is left lateral usually).
Path of an O₂ molecule from nares to pulmonary capillaries
Nares → nasal cavity (warmed/filtered) → nasopharynx → oropharynx → laryngopharynx → larynx → trachea → main bronchi → lobar bronchi → segmental bronchi → bronchioles → terminal bronchioles → respiratory bronchioles → alveolar ducts → alveolar sacs/alveoli → across alveolar epithelium + capillary endothelium → pulmonary capillary blood. Shift from gas-transport to gas-exchange: at the respiratory bronchioles & alveoli — gas exchange begins at respiratory bronchioles and is maximal in alveoli.
Path of a red blood cell (right atrium → back again)
Right atrium → tricuspid valve → right ventricle → pulmonary valve → pulmonary arteries → pulmonary arterioles → pulmonary capillaries (in lungs; gas exchange — RBC picks up O₂) → pulmonary venules → pulmonary veins → left atrium → mitral (bicuspid) valve → left ventricle → aortic valve → aorta → systemic arteries → arterioles → systemic capillaries (deliver O₂ to tissues) → venules → systemic veins → superior/inferior vena cava → right atrium.
Three layers of the heart
• Endocardium (inner lining) • Myocardium (muscular middle layer) • Epicardium (outer layer; visceral pericardium). The heart is enclosed in the pericardial sac (parietal pericardium).
Systolic BP represents what? What are atria doing? What creates a palpable pulse?
• Systolic BP: Pressure produced when the ventricles contract (ventricular systole), primarily left ventricular ejection into the aorta. • Atria at that moment: Atria are in diastole (filling) while ventricles contract. • Palpable pulse: Created by the surge of blood ejected from the left ventricle into arteries — the pressure wave traveling along arterial walls.
Vital sign changes with age; normal adult ranges
• As child ages: Heart rate and respiratory rate decrease with age; blood pressure increases with age. Infants have highest HR/RR, adolescents approach adult norms. • Normal adult respiratory rate: ~12–20 breaths/min. • Normal adult systolic BP range: Generally ~90–120 mmHg (90–140 sometimes accepted depending on source); often use 90–120 as normal resting systolic.
Path of a bolus of food (mouth → anus) & digestion sites
Mouth (mastication + saliva: carbohydrate digestion begins here by salivary amylase) → pharynx → esophagus → stomach (mechanical + acidic protein digestion begins; protein digestion starts in stomach via pepsin) → small intestine (duodenum, jejunum, ileum — majority of digestion & absorption; fats primarily digested in small intestine with bile & pancreatic lipase) → large intestine/colon (water absorption, bacterial fermentation; formation of feces; some vitamin absorption). Colon role: Absorption of water/electrolytes, bacterial fermentation, formation/storage of feces.
Three muscle types & examples
• Smooth muscle (a): Involuntary, non-striated, controlled by autonomic nervous system; found in vessel walls, bronchioles, GI tract; slow, sustained contractions. Bronchiole muscle = smooth muscle. • Striated (skeletal) muscle (b): Voluntary, multinucleated, striated; under somatic nervous system control; produces gross movement (e.g., biceps brachii flexion, thigh adductors). Adducts femur or flexes bicep = skeletal (striated) muscle. • Cardiac muscle (c): Involuntary, striated, with intercalated discs for synchronized contraction; found only in heart.
Brain regions & spinal segments
• Three basic brain regions: Cerebrum (higher functions), cerebellum (coordination/balance), brainstem (midbrain, pons, medulla — vital center control). • Spine segments (descending): Cervical (7 vertebrae C1–C7), Thoracic (12 T1–T12), Lumbar (5 L1–L5), Sacral (5 fused S1–S5), Coccyx (4 fused). • Where brain & spinal cord connect: At the foramen magnum; specifically the brainstem (medulla) continues as the spinal cord.
Life stage age groups (common EMS classifications)
• Infant: Birth–1 year. • Toddler: 1–3 years. • Preschooler: 3–5 years. • School-aged child: 6–12 years. • Adolescent: 13–18 years (some sources use up to 21). • Young adult: ~19–40 years. • Middle adult: ~41–65 years. • Older adult (geriatric): 65+ years. (Exact cutoffs vary by textbook; these are common clinical ranges.)
Standard patient move vs emergency move
• Standard move: Performed when scene is safe and you can assess, package, and move patient using correct lifting technique and equipment (e.g., long-board/stretcher). • Emergency move: Performed when immediate movement is required for safety or to provide life-saving care (fire, explosion risk, airway compromise). Done quickly without full immobilization. • Appropriate time: If scene becomes dangerous or patient must be moved to provide life-saving interventions (e.g., CPR), perform an emergency move.
Describe the power lift
Feet shoulder-width, one foot slightly ahead. Bend at knees and hips (not waist). Keep back locked, chest up, shoulders “stacked” over hips. Grip close to body. Lift using legs (quadriceps/gluteals) in a smooth motion; avoid twisting — pivot with feet.
“Stack” shoulders, hips, legs; what part to primarily lift with; where majority of weight resides
• Stacking: Align shoulders over hips over feet so spine is neutral and load is centered. • Primary lifting with: Legs (not back) — use gluteal and quadriceps muscles. • Majority of body weight: In adults, the torso/trunk (center of mass around the pelvis/abdomen) — keep load close to your body to reduce torque.
Sign vs symptom
• Sign: Objective finding observed/measured by provider (e.g., cyanosis, JVD). • Symptom: Subjective complaint reported by patient (e.g., pain, tinnitus). Label the list: a. Hematemesis — sign (objective—vomiting blood) b. Angina — symptom (chest pain reported) c. Cyanosis — sign d. Jugular vein distension — sign e. Dysuria — symptom (painful urination reported) f. Urticaria — sign (hives observed) g. Pruritis — symptom (itching reported) h. Delayed capillary refill — sign (objective) i. Pupillary constriction — sign (objective) j. Tinnitus — symptom (ringing in ears reported)
