3.2 Emergency Response Procedures
Key Takeaways
- Adult BLS follows C-A-B: start compressions immediately after a no-pulse check, at 100-120/min, at least 2 inches but no more than 2.4 inches deep.
- Compression-to-ventilation ratio is 30:2 for single-rescuer adult, child, and infant CPR, and 15:2 for two-rescuer child and infant CPR.
- Per 2025 AHA guidance, conscious adult/child choking uses cycles of 5 back blows then 5 abdominal thrusts; infants get 5 back blows then 5 chest thrusts (never abdominal thrusts).
- Anaphylaxis is treated first with intramuscular epinephrine 0.3-0.5 mg (1 mg/mL) in the mid-outer thigh, not diphenhydramine.
- Recognize stroke with FAST and treat it as time-critical: 'time is brain.'
Acting in the First Minutes
The NCLEX-PN tests emergency response as priority-of-action items. The recurring framework is C-A-B for circulation-first resuscitation and ABC (airway-breathing-circulation) for assessing a patient who still has a pulse. Knowing which framework the scenario calls for is the difference between a correct and incorrect answer.
Adult Basic Life Support (2025 AHA Guidelines)
| Step | Action |
|---|---|
| 1 | Check responsiveness — tap and shout |
| 2 | Activate emergency response, call for the AED and crash cart |
| 3 | Check carotid pulse for no more than 10 seconds |
| 4 | If no pulse, begin compressions immediately |
| 5 | Open airway (head-tilt/chin-lift), give breaths if trained |
| 6 | Attach the AED the moment it arrives, follow prompts |
Compression standards across age groups:
| Element | Adult | Child (1 yr-puberty) | Infant (under 1 yr) |
|---|---|---|---|
| Rate | 100-120/min | 100-120/min | 100-120/min |
| Depth | At least 2 in, max 2.4 in | About 2 in (1/3 chest) | About 1.5 in (1/3 chest) |
| Technique | Two hands, heel on lower sternum | One or two hands | 2-thumb encircling or 1-hand (2-finger no longer preferred) |
| Ratio, 1 rescuer | 30:2 | 30:2 | 30:2 |
| Ratio, 2 rescuers | 30:2 | 15:2 | 15:2 |
Allow full chest recoil between compressions and minimize interruptions to under 10 seconds. When an AED arrives, power it on, attach pads (one upper-right chest, one lower-left side), clear everyone and let it analyze, deliver a shock if advised, then immediately resume compressions for about 2 minutes before re-analyzing. For a witnessed adult collapse where an AED is at hand, attach it as soon as possible; otherwise compressions come first. The single most common test error is stopping or delaying compressions to check a pulse, ventilate, or fetch equipment.
Recognize agonal gasping as not normal breathing — a gasping, pulseless patient is in cardiac arrest and needs compressions. If a lone rescuer finds an unwitnessed pediatric or infant arrest, current guidance still emphasizes early compressions and rapid activation of help; pediatric arrests are more often respiratory in origin, so high-quality ventilation matters more than in adults.
Choking (Foreign-Body Airway Obstruction)
If the victim can cough or speak, encourage coughing and do not intervene — a partial obstruction is moving air. For complete obstruction (clutching the throat, no air movement):
- Conscious adult or child: 2025 AHA guidance now recommends repeated cycles of 5 back blows then 5 abdominal thrusts until the object clears or the victim becomes unresponsive.
- Infant under 1 year: alternate 5 back blows and 5 chest thrusts (using the heel of one hand); abdominal thrusts are never used in infants because of liver-injury risk.
- Unresponsive victim: begin CPR; before each set of breaths, look in the mouth and remove an object only if visible (no blind finger sweeps).
Anaphylaxis
Anaphylaxis is a rapid, IgE-mediated, life-threatening reaction — bronchospasm, laryngeal edema, hypotension, hives, and a sense of impending doom.
| Priority | Action |
|---|---|
| 1 | Stop the trigger (e.g., stop the IV antibiotic) and call for help |
| 2 | Give intramuscular epinephrine 0.3-0.5 mg of 1 mg/mL in the mid-outer thigh |
| 3 | Maintain a patent airway, give high-flow oxygen |
| 4 | Position supine with legs elevated if no respiratory distress |
| 5 | Establish IV access for fluids; antihistamines and steroids are adjuncts, not first-line |
Epinephrine is always first — diphenhydramine and corticosteroids treat the secondary response but do not reverse airway collapse or shock. Epinephrine works by causing vasoconstriction (raising blood pressure), bronchodilation (opening the airway), and reduced mediator release. The dose may be repeated every 5-15 minutes if symptoms persist. Watch for a biphasic reaction, in which symptoms recur hours after the initial response resolves, so the patient is monitored for several hours even after improving.
Shock at a Glance
| Type | Cause | Distinguishing signs |
|---|---|---|
| Hypovolemic | Blood/fluid loss | Tachycardia, cool clammy skin |
| Cardiogenic | Pump failure | Jugular distension, crackles |
| Septic | Infection | Warm flushed skin early, then hypotension |
| Neurogenic | Spinal cord injury | Bradycardia, warm dry skin |
| Anaphylactic | Allergen | Hives, angioedema, wheezing |
Stroke and Chest Pain
Screen stroke with FAST (some facilities use BE-FAST, adding Balance and Eyes): Face droop, Arm drift, Speech slurring, Time to call for help and note onset. Document the last known well time — it drives eligibility for thrombolytics (tissue plasminogen activator must generally be given within about 3-4.5 hours of onset for ischemic stroke). Keep the patient NPO until a swallow screen is done, because dysphagia and aspiration are major post-stroke risks.
For chest pain, the LPN remembers MONA as a memory aid (Morphine, Oxygen, Nitroglycerin, Aspirin) while recognizing that the priority assessment is staying with the patient, applying continuous monitoring, and obtaining a 12-lead ECG. Place the patient in semi-Fowler's, give oxygen if hypoxic, and administer chewable aspirin and nitroglycerin if ordered — but hold nitroglycerin if the systolic blood pressure is below 90 mmHg or the patient has taken a phosphodiesterase inhibitor (such as sildenafil) within 24-48 hours, because of severe hypotension risk.
Assess pain with the PQRST mnemonic: Provocation, Quality, Region/Radiation, Severity (0-10), and Timing.
Common NCLEX-PN Traps
- Pausing compressions to wait for the AED.
- Choosing diphenhydramine over epinephrine in anaphylaxis.
- Using abdominal thrusts on an infant.
- Applying ABC sequencing to a pulseless arrest instead of starting compressions.
A patient becomes unresponsive and the LPN confirms there is no carotid pulse within 10 seconds. What should the LPN do NEXT?
A 6-month-old infant suddenly cannot cry or cough after putting a small toy in the mouth. What should the LPN do?
Minutes into an IV antibiotic infusion, a patient develops wheezing, facial swelling, and a falling blood pressure. After stopping the infusion and calling for help, which intervention is the priority?