Basic life support Study Guide

📖 Core Concepts Basic Life Support (BLS) – Immediate, lifesaving care for cardiac/respiratory arrest until advanced life support arrives. AVPU Scale – Quick consciousness check: Alert, responds to Verbal, responds to Pain, Unconscious. Jaw‑thrust vs. Head‑tilt – Jaw‑thrust opens airway without moving the cervical spine; head‑tilt can worsen spinal injury. Chain of Survival (5 links) – Early recognition → Bystander CPR → Early AED → Advanced life support → Post‑cardiac‑arrest care. AED – Device that analyzes rhythm and delivers a shock if a shockable rhythm is present; early use (first 3–5 min) yields 50–70 % survival. 📌 Must Remember Compression rate: 60 compressions/min (≈ 1 sec per compression) for all ages. Adult compression‑to‑ventilation ratio: 30:2. Child/infant ratio (2 rescuers): 15:2. Compression‑only CPR – Acceptable for up to 5 min if rescuer cannot give breaths. AED shockable rhythms: Ventricular fibrillation (VF) & pulseless ventricular tachycardia (VT). Non‑shockable rhythms: Asystole, pulseless electrical activity (PEA) – continue CPR, no shock. Rescue breathing priority: Infants/toddlers (respiratory arrest) and drowning victims. Choking relief: Back slaps → abdominal thrusts (adults); back slaps → chest thrusts (infants, pregnant, obese). 🔄 Key Processes Scene safety – Verify no ongoing danger (electricity, fire, water). Assess responsiveness – Use AVPU; shout, tap, then pain if needed. Call EMS – If unresponsive and not breathing normally, activate emergency services. Open airway – Perform jaw‑thrust (spinal precautions). Check breathing – Look, listen, feel for ≤ 10 seconds. Start CPR – Adults: 30 compressions → 2 breaths. Children/infants (2 rescuers): 15 compressions → 2 breaths. Apply AED – After 2 min of compressions, turn on AED, attach pads, follow prompts. Post‑shock – Resume compressions immediately for 2 min, then reassess rhythm. Special cases – Drowning: prioritize rescue breaths; choking: back slaps → thrusts, then CPR if unresponsive. 🔍 Key Comparisons Jaw‑thrust vs. Head‑tilt – Jaw‑thrust (spine‑safe) vs Head‑tilt (may move C‑spine). Compression‑only CPR vs. Standard CPR – Compression‑only (no breaths) vs 30:2 (breaths added). Adult vs. Child/Infant ratio – Adults 30:2 vs Children/Infants 15:2 (when 2 rescuers). Back slap vs. Abdominal thrust – Back slap (initial, all ages) vs Abdominal thrust (adults only; chest thrust for pregnancy/obesity/infants). ⚠️ Common Misunderstandings “If I can’t give breaths, I shouldn’t do CPR.” – Wrong; compression‑only CPR is effective for up to 5 min. “Head‑tilt always opens airway.” – Incorrect when spinal injury is possible; use jaw‑thrust. “AED shock is always needed.” – AED only shocks shockable rhythms; otherwise continue CPR. “Infants need abdominal thrusts for choking.” – Wrong; infants receive back slaps → chest thrusts. 🧠 Mental Models / Intuition “C‑A‑R‑D” flow: Check scene, Assess responsiveness, Respond (call EMS + start CPR), Defibrillate (AED). “30‑seconds rule” – Roughly 30 seconds of compressions equals 30 compressions at 60 /min; helps keep rhythm on track. “Shock‑or‑No‑Shock” – If AED says “Shock advised,” deliver; if “No shock,” keep compressing. 🚩 Exceptions & Edge Cases Pregnant, obese, or infant choking – Use chest thrusts instead of abdominal thrusts. Drowning victim – Emphasize rescue breaths first because hypoxemia drives arrest. Single rescuer unable to give breaths – Perform compression‑only CPR for up to 5 min before switching if able. 📍 When to Use Which Compression‑only vs. 30:2: Use compression‑only if you cannot or won’t give breaths (e.g., mouth‑to‑mouth hesitation). AED vs. manual defibrillation: Use AED for lay rescuers or when no manual defibrillator is available; follow prompts. Abdominal vs. Chest thrust: Choose chest thrust for pregnant, obese, or infant patients; abdominal thrust for typical adults. 👀 Patterns to Recognize Unresponsive + not breathing normally → Immediate CPR & call EMS. Sudden collapse in a witnessed adult → Likely VF/VT → Early AED shock needed. Drowning or infant collapse → Primary problem is respiratory → Rescue breaths critical. Silent cough, cyanosis, inability to speak → Severe choking → Back slap → Thrust sequence. 🗂️ Exam Traps “If a patient is breathing, no CPR is needed.” – Correct only if breathing is normal; agonal breathing still requires CPR. “AED should be used after 5 min of CPR.” – Wrong; AED should be applied as soon as it’s available (after 2 min of compressions). “Head‑tilt‑chin‑lift is always the best airway maneuver.” – Misleading; jaw‑thrust is preferred when spinal injury is suspected. “Adult compression depth is the same for infants.” – Incorrect; infants require less force (≈ 1.5 in vs. 2‑2.4 in for adults). --- Use this guide for a rapid, high‑yield review before your BLS exam. Good luck!