ECG

• Primary pacemaker of <3 = Sinoatrial node

  Secondary pacemaker = Atrioventricular node
• SA node

  -60-100 bpm

  -Atrium: collects blood
• AV node

  -40-60 bpm

  -ventricle: delivers blood to the body
• SA node (collects)

  AV node (delivers)

  Nerves: Bundle of His & Purkenji Fibers (signals end of contraction)
• normal sinus rhythm

  
• Identify:

  -P wave

  -QRS Complex

  -T wave

  -PR interval

  -ST segment

  
• P wave

  -SA node

  -60-100 bpm

  -Atrial depolarization (contraction)

  -"Lub" @ S1
• QRS Complex

  -AV node

  -40-60 bpm

  -Ventricular depolarization

  -"Dub" @ S2
• T wave

  -end of contraction

  -sensitive to potassium imbalance
• PR interval

  -atrial repolarization (rest)

  -0.12-0.20 sec

  -if > 20 sec = Heart block, priority!
• ST segment

  -ventricular repolarization

  -WOF: Myocardial Infarction (MI)
• atrial flutter & atrial fibrillation are not priority because they are chronic disease
• What rhythm? Atrial flutter aka "saw toothed"

  -what wave problem: P wave

  -150-250 bpm

  -high chance of clot formation

  brain = stroke

  lungs = pulmonary embolism

  lower extremities = DVT

  
• What rhythm: Atrial fibrillation aka "Quivering"

  -which wave prob: P wave

  -200-400 bpm

  -high chance of clot formation

  
• Management for atrial rhythms = to prevent clot formation

  1. Anti-coagulants
  2. Anti-platelets
  3. Thrombolytics
• Anti-coagulants aka blood thinners

  1. Heparin

  -route: IV or SQ

  -Antidote: Protamine SO4

  -Labs: aPTT

  2. Warfarin

  -route: oral

  -antidote: vitamin K aka aquamephyton

  -labs: PT & INR
• Anti-coagulants aka blood thinners

  3. Enoxaparine aka "baby heparin"

  -route: SQ

  -low molecular weight heparin (LMWH)

  -antidote: protamine SO4

  -labs: aPTT

  -special consideration: ⭐ do not inject bubbles
• Anti-platelets drugs

  1. clopidogrel 2. aspirin

  A/E: bleeding!

  WOF: Melena, GI upset, Hematemesis

  Mgt: Amicar

  Special consideration: give with meals
• Aspirin

  -Salicylate = WOF: Reye's syndrome (always dangerous): brain and liver bleeding
• Thrombolytics aka "clot busters"

  -Streptokinase, Urokinase, Alteplase

  -A/E: Bleeding!

  -Mgt: Amicar
• Atrial meds to be given:

  Procainamide & Quinidine

  -both are Sodium Calcium Blockers
• ventricular problems are all priority! - if the heart is not pumping blood, it will not be able to get oxygenated blood to the body
• What rhythm: supraventricular problem

  -Which wave problem: narrowed QRS wave; p wave rarely visible

  -[sobrang taas + dikit dikit]

  -Meds: Adenosine; initial dose? 6 mg then 12 mg, 12 mg [adenosix]

  -Mgt: Syncronized cardioversion if stable rhythm & conscious)

  
• Rhythm: Premature ventricular contraction (PVC)

  wave problem: wide and bizarre QRS wave

  how many in a row: 3, therefore action is report!

  priority because can lead to Vtach!

  also report when 6 in a 1 minute strip!

  Mgt: Lidocaine

  
• Rhythm: Monomorphic ventricular tachycardia

  -one-shape only

  wave problem: (-) p wave, (-) QRS

  mgt: if stable = Lidocaine

  if unstable = CIDEA; code blue initiate cpr defibrillation epinephrine amiodarone

  unstable is = HR of > 150 bpm & unconscious

  
• rhythm: torsades de pointes aka polymorphic (distorted)

  wave problem: (-) p wave, (-) qrs

  mgt: MgSO4

  
• Rhythm: Ventricular fibrillation aka chaotic

  wave problem: (-) p wave (-) qrs wave

  mgt: CIDEA

  -code blue

  -initiate cpr

  -defibrillation

  -epinephrine

  -amiodarone

  -shockable? Yes

  
• 2 shockable rhythms: Vtach (unstable) & Vfib