PALS | Recognition of Pedi Arrhythmias

1️⃣ Bradyarrhythmias (Slow Rhythms)Definition: HR <60 bpm with poor perfusion = treat immediately.🌡️ CausesHypoxia (MOST COMMON), heart block, vagal stimulation, hypothermia, drugs.🫀 Sinus BradycardiaRecognition: P waves present, regular rhythm, slow rate.Peds Tip: Normal in athletes/sleeping; NOT normal with poor perfusion.🟪 AV Blocks1° AV Block:PR prolonged (>0.20s adult-equivalent), but every P → QRS.Usually benign; watch for progression.2° Type I (Wenckebach):PR progressively lengthens → dropped QRS.“Longer, longer, longer, drop ▶️ Wenckebach.”Usually transient, often vagal.2° Type II:Normal PR intervals with random dropped QRS.Bad. Can progress to complete block.3° Complete Heart Block:Atria + ventricles beat independently.Regular P waves, regular QRS—but no relationship.Often bradycardic, poor perfusion.2️⃣ Tachyarrhythmias (Fast Rhythms)Definition: Above age-appropriate range (often >180 infants, >160 children).⚡ Supraventricular Tachycardia (SVT)Rate: 180–300 bpmP waves: Absent or hiddenQRS: NarrowOnset: AbruptKey Tip: Infant may just appear irritable, poor feeding, or pale.⚡ Atrial FlutterSawtooth F-wavesRate often 250–350Rare in kids (post-op congenital heart disease)⚡ Ventricular Tachycardia (VT)With Pulse:Wide QRS, regular rhythmRate usually 120–250May have poor perfusionPulseless VT:Treat like VF (defibrillate)💥 Ventricular Fibrillation (VF)Chaotic, no identifiable wavesNo pulse → CPR + defibrillate immediately😵 Asystole (Flatline)No electrical activityConfirm in 2 leadsCPR + epinephrine only (NO shock)🌪️ PEA (Pulseless Electrical Activity)Organized electrical rhythm without a pulseCauses = H’s & T’s (hypoxia, hypovolemia, hypothermia, H+ acidosis, hypo/hyperK, tension pneumo, tamponade, toxins, thrombosis)3️⃣ How to Rapidly Recognize Rhythms (PALS Algorithm)Step 1: Pulse CheckPresent? → Rhythm with pulseAbsent? → Treat as cardiac arrest rhythmStep 2: Narrow vs. Wide QRSNarrow (<0.08s): SVT, sinus tach, atrial flutter/fibWide (>0.08–0.12s): VT, aberrancyStep 3: Regular vs. IrregularRegular: SVT, VT, sinus tachIrregular: Atrial fibrillation/flutter with variable block, polymorphic VTStep 4: P Waves Present?Yes → sinus or atrial rhythmNo → SVT or VT