You walk into a code on a child. Heart rate 38, eyes rolled back, mom screaming. Your hands need to know what to do before your brain catches up — and that is the whole point of memorizing the PALS algorithms cold. The American Heart Association wrote these flowcharts for one reason. When seconds matter, you stop guessing.

This reference walks through every pediatric advanced life support algorithm that shows up on the AHA exam and, more importantly, in the trauma bay. Cardiac arrest. Bradycardia. Tachycardia with a pulse. Shock. Respiratory failure. Each pathway has its own decision points, drug doses, and joules. Mix them up and a kid dies.

Most providers fail the recert not because they forgot the algorithm. They forgot the numbers. The 0.01 mg/kg. The 2 J/kg first shock. The 6 L/min flow. So that's where we're going to spend most of our time — the exact figures the test loves to bury inside a clinical vignette.

Heads up: this is a clinical reference, not a substitute for taking the course. The AHA Provider Manual stays the gold standard. But if you need a quick refresh before tomorrow's shift or a recert next week, this gets you there.

Let's start with the algorithm everybody dreads — pediatric cardiac arrest. The kid is pulseless. You're starting chest compressions before the monitor is even on. That's a non-negotiable. Pulse check takes no more than ten seconds, and the moment you don't feel one, compressions start. Push hard, push fast: 100–120 per minute, depth one-third the chest AP diameter (about 1.5 inches in infants, 2 inches in older children).

The rhythm dictates the rest. Shockable (VF/pVT) goes one way. Non-shockable (asystole/PEA) goes another. That fork in the algorithm is the single biggest decision in the entire code.

For shockable rhythms — first shock is 2 J/kg. Second shock 4 J/kg. Subsequent shocks at least 4 J/kg, maximum 10 J/kg or the adult dose, whichever is lower. Resume compressions immediately after every shock. Don't pause to check the rhythm; that wastes perfusion time. You'll see what happened at the next two-minute pulse check.

Epinephrine comes in at the same dose regardless of rhythm — and yes, the test will ask. 0.01 mg/kg IV or IO every 3–5 minutes. That's 0.1 mL/kg of the 1:10,000 concentration. Maximum single dose is 1 mg. Endotracheal route works if you can't get a line — 0.1 mg/kg of the 1:1,000 concentration — but IV/IO beats ET every time. Give it during compressions, not between cycles.

Amiodarone or lidocaine after the third shock if VF/pVT keeps returning. Amiodarone dose: 5 mg/kg IV/IO bolus, can repeat twice for refractory VF/pVT. Lidocaine: 1 mg/kg loading dose. Both are second-line behind epinephrine.

Don't forget the H's and T's. Hypovolemia. Hypoxia. Hydrogen ion (acidosis). Hypo/hyperkalemia. Hypoglycemia. Hypothermia. Tension pneumothorax. Tamponade. Toxins. Thrombosis (pulmonary or coronary). Trauma. If your kid stays in cardiac arrest, one of these is the reason. Hunt them down between shocks.

Bradycardia algorithm next. The trigger is heart rate under 60 with cardiopulmonary compromise — poor perfusion, hypotension, altered mental status, signs of shock. A kid with a heart rate of 55 who's chatting and pink doesn't need the algorithm. A pale, mottled infant at 70 with capillary refill of 5 seconds does.

Step one is always the same: support airway, give 100% oxygen, attach monitor. Then look at the rhythm. If the compromise persists despite oxygenation and ventilation — and this matters because most pediatric bradycardia is hypoxic in origin — start chest compressions. The threshold is HR under 60 with poor perfusion. That number sticks. Below 60 + poor perfusion = compressions.

Epinephrine remains the first-line drug. Same dose: 0.01 mg/kg IV/IO every 3–5 minutes. Atropine is reserved for primary AV block or increased vagal tone. Atropine dose: 0.02 mg/kg, minimum single dose 0.1 mg, maximum single dose 0.5 mg. Pacing (transcutaneous) goes on the table for refractory bradycardia, but in practice you fix the hypoxia first and rarely need to pace.

Now tachycardia with a pulse. This is where most providers blank, because the algorithm forks twice. First fork: stable vs. unstable. Second fork: narrow vs. wide complex.

Unstable means signs of cardiopulmonary compromise — hypotension, altered mental status, signs of shock. Unstable plus any tachycardia goes straight to synchronized cardioversion. Initial dose of synchronized cardioversion in PALS is 0.5 to 1 J/kg. If that fails, increase to 2 J/kg. Sedate if you have time and the patient is conscious. Never delay cardioversion in a deteriorating child for sedation logistics.

Stable narrow-complex tachycardia? Probably SVT. Try vagal maneuvers first — ice to the face for infants, blow-into-a-straw for older kids. If that doesn't break it, adenosine 0.1 mg/kg rapid IV push (max first dose 6 mg), followed by saline flush. Second dose: 0.2 mg/kg (max 12 mg). Adenosine has a half-life of seconds, so the push has to be fast and followed immediately by flush.

Stable wide-complex tachycardia? Possible VT. Amiodarone 5 mg/kg over 20–60 minutes, or procainamide 15 mg/kg over 30–60 minutes. Don't mix the two — additive QT prolongation. Cardiology should be at the bedside before you start either.

Atrial flutter shows up on PALS exams as a rhythm-recognition question almost every test cycle. Characteristics of atrial flutter on PALS: sawtooth-pattern flutter waves on ECG (best seen in leads II, III, aVF), atrial rate typically 250–350 in older children (faster in infants, up to 400+), and a ventricular rate that depends on the AV conduction ratio (2:1, 3:1, 4:1 block patterns). The classic ECG buzzword is "sawtooth." If you see sawtooth, you say flutter. Treatment for unstable flutter is synchronized cardioversion, starting at 0.5–1 J/kg, same as any unstable tachyarrhythmia.

Pediatric shock has its own algorithm and four flavors that you absolutely must distinguish: hypovolemic, distributive, cardiogenic, and obstructive. The flavor changes the treatment.

Hypovolemic is the most common — gastroenteritis with dehydration, hemorrhage from trauma, third-spacing in burns or sepsis. Treatment is volume. 20 mL/kg isotonic crystalloid (normal saline or lactated Ringer's) over 5–20 minutes. Reassess. If still hypoperfused, repeat. After 60 mL/kg without improvement, think about another cause and start vasoactive support.

Distributive includes septic, anaphylactic, and neurogenic. Sepsis is fluid-responsive early — push 20 mL/kg quickly and start broad-spectrum antibiotics within the first hour. Anaphylaxis needs IM epinephrine fast.

The most appropriate treatment for severe anaphylaxis in PALS is intramuscular epinephrine, 0.01 mg/kg of the 1:1,000 concentration, max single dose 0.5 mg, into the anterolateral thigh. Repeat every 5–15 minutes as needed. IM beats subcutaneous and beats waiting on IV access. Adjuncts — albuterol, antihistamines, steroids, fluids — are all secondary. Epi first.

Cardiogenic shock means the pump itself is failing — myocarditis, dilated cardiomyopathy, post-cardiac-surgery dysfunction, intoxication with a cardiotoxic drug. Fluid boluses here are dangerous; you can flip a struggling ventricle into pulmonary edema with one careless 20 mL/kg bolus. Smaller boluses (5–10 mL/kg) with frequent reassessment, and early inotropic support — epinephrine infusion, milrinone, dopamine.

Obstructive shock means flow is mechanically blocked. Tension pneumothorax. Cardiac tamponade. Massive pulmonary embolism. Critical aortic stenosis or coarctation in a neonate. The fix is mechanical — needle decompression, pericardiocentesis, thrombolysis, prostaglandin. Volume and pressors are bridging measures only.

Hypotensive shock in PALS means the compensatory mechanisms have failed. Blood pressure has dropped below the fifth percentile for age. This is late shock. By the time you see hypotension in a child, the kid has been compensating for a long time — and is about to crash. Don't wait for hypotension to call shock. Recognize compensated shock first: tachycardia, narrow pulse pressure, cool extremities, delayed capillary refill, altered mental status. Treat aggressively before the pressure drops.

Respiratory emergencies are where most pediatric arrests come from. Adults arrest because their hearts stop. Kids arrest because their lungs stop. So PALS spends a disproportionate amount of time on airway and breathing, and the test will too.

The first systematic question is: where in the respiratory system is the problem? Upper airway obstruction (croup, foreign body, anaphylaxis). Lower airway obstruction (asthma, bronchiolitis). Lung tissue disease (pneumonia, ARDS). Disordered control of breathing (CNS depression, neuromuscular disease, intoxication).

Signs of disordered control of breathing in PALS include irregular respiratory rate or pattern, central apnea, shallow respirations without retractions, and decreased respiratory effort despite hypoxia. The clue is that the respiratory effort doesn't match the clinical severity. A kid with disordered control isn't fighting to breathe; they've stopped trying. Think CNS injury, narcotic overdose, severe sepsis, neuromuscular fatigue.

This contrasts with upper or lower airway obstruction where you'll see retractions, stridor or wheezing, and the kid is clearly working hard. Disordered control = the work isn't there.

Oxygen delivery devices come up on every PALS exam. Know the flow rates and the delivered FiO2 cold:

Nasal cannula: 1–6 L/min, delivers 22–44% FiO2. Comfortable, kid-friendly, but the FiO2 ceiling is low.

Simple face mask: 6–10 L/min flow rate, delivers 35–60% FiO2. The appropriate flow rate for a simple mask in PALS is 6–10 L/min. Below 6 the patient rebreathes exhaled CO2 trapped in the mask. Above 10 you're not gaining FiO2, just wasting oxygen.

Non-rebreather mask: 10–15 L/min flow rate, delivers up to 95% FiO2 when sealed properly with one-way valves intact. This is the go-to for moderate to severe distress while you're setting up for definitive airway.

High-flow nasal cannula: 1–60 L/min depending on system. Delivers heated, humidified gas with adjustable FiO2 — useful bridge for moderate respiratory distress, increasingly common in pediatric ICUs.

Bag-mask ventilation: rate of 12–20 breaths per minute in children, 30 in neonates. Avoid over-ventilation. Hyperventilation in PALS results in respiratory alkalosis, decreased cerebral blood flow, decreased venous return, and decreased cardiac output. Squeezing the bag too fast doesn't help — it hurts. Slow and steady wins the resuscitation.

Endotracheal intubation isn't a routine PALS skill, but if it's done, tube size matters. Uncuffed tube size: (age in years / 4) + 4. Cuffed tube: (age / 4) + 3.5. Confirm placement with end-tidal CO2 capnography — the AHA standard. Depth of insertion at the lips: tube size × 3.

If a tube is in place during cardiac arrest, you stop the 30:2 ratio. Compressions become continuous at 100–120 per minute. Ventilations go in once every 6 seconds, which works out to 10 per minute. Don't synchronize. Don't pause compressions for breaths.

Vascular access. IV first, IO if you can't get it within 90 seconds or after 2 attempts. Intraosseous access through the proximal tibia is fast, reliable, and works with every drug and fluid you'd push through an IV — including epinephrine, amiodarone, blood products, and crystalloid boluses. The team that hesitates on IO loses the resuscitation. Drill first, apologize later.

Push drugs followed by 5 mL saline flush in infants, 10 mL in older children. Elevate the limb after the flush to speed circulation. Resume compressions immediately.

Post-arrest care matters as much as the code itself. Survival to discharge depends on what you do in the first 24 hours after return of spontaneous circulation. Targeted temperature management — 32–34°C for 2 days, then 36–37.5°C for 3 days, or continuous normothermia 36–37.5°C for 5 days, depending on the protocol your institution uses. Treat seizures aggressively. Maintain normocarbia (avoid both hyperventilation and hypoventilation). Maintain normoglycemia.

Glucose check is mandatory in any arrested child. Hypoglycemia is reversible and missed often. D10 at 5 mL/kg in infants, D25 at 2 mL/kg in older children, D50 at 1 mL/kg in adolescents. Different concentrations, same intent: get the sugar to 60–110 mg/dL.

The AHA published the most recent pediatric guidelines in 2020, with focused updates in 2023 and 2024. The big-ticket items that are now standard: cuffed endotracheal tubes are acceptable from infancy onward; family presence during resuscitation should be offered when feasible; post-arrest blood pressure should be maintained above the fifth percentile for age; and end-tidal CO2 monitoring is recommended during all resuscitations, not just after intubation.

If you're preparing for recertification, the algorithms haven't fundamentally changed — but the supporting recommendations have. Read the executive summary on the AHA website, and check our PALS practice test page to pressure-test your recall under timed conditions.

One more pitfall worth flagging. Pediatric providers tend to over-resuscitate volume in septic shock. The 2020 guidelines pulled back from the aggressive 60 mL/kg first-hour bolus recommendation because of fluid overload data in low-resource settings. The current standard: 10–20 mL/kg boluses with frequent reassessment, and earlier vasopressor support when fluid responsiveness is unclear. Don't keep pushing crystalloid into a child who's developing crackles and a rising oxygen requirement. Switch to epinephrine infusion at 0.05–0.3 mcg/kg/min.

Norepinephrine is also acceptable, particularly in warm shock with vasodilation. Dopamine is fading from first-line use in modern pediatric guidelines but still appears on the exam — know the dose: 2–20 mcg/kg/min.

Final pull-together. PALS is twenty years of pediatric resuscitation research distilled into roughly twelve algorithms. You will not memorize them by reading. You memorize them by drilling — flashcards, simulation, megacode scenarios, and repetition. The numbers stick when you've said them out loud a hundred times.

Epinephrine 0.01 mg/kg every 3–5 minutes. First shock 2 J/kg. Sync cardioversion 0.5–1 J/kg. Simple mask 6–10 L/min. Amiodarone 5 mg/kg. Adenosine 0.1 mg/kg. Atropine 0.02 mg/kg. Glucose D10 5 mL/kg in infants. Compress to one-third chest depth, 100–120 per minute. Continuous compressions once intubated, with breaths every 6 seconds.

Print this. Tape it to your code cart. Run scenarios on quiet nights. The kid who codes on your shift is not going to wait while you flip through a manual.