ECG Cards

• Method 1:  80 beats per minute (8 intervals)
• Method 2:  75 beats per minute (4 lg boxes)
• Method 3:  84 beats per minute  (18 small boxes)

• Each Small box = 0.04 sec
• Each Large box = 0.20 sec

a) P-P interval

b) R-R interval

The spacing between R-R and/or P-P is equal throughout the strip

a) a P-wave is present

b) SA node is firing to produce a P-wave

• c) True, it can be irregular sinus rhythm if it still has a p-wave. The description of this tracing is:
• * Ventricular rate/rhythm: 41-73 bpm, irregular
• * PR interval: 0.20 sec
• * QRS interval: 0.12 sec
• * Identification: Sinus rhythm at 41-73 bpm with a nonconducted PAC

a) Coarse V-fib

• b) Defining ECG Criteria:
• Rate:       Cannot be determined; no recognizable P, QRS, or T waves. Baseline undulations btwn
• 150-500/min

Rhythm:        Indeterminate; pattern of sharp up (peak) and down (trough) deflections

Amplitude:     Measured from peak-to-trough

Fine V-Fib:      Peak-to-trough   2 to < 5mm

Moderate V-Fib:   Peak-to-trough  5 to < 10mm

Coarse  V-Fib:     Peak-to-trough  10 to <15mm

Very Coarse V-fib:   Peak-to-trough  >15mm

a) Fine V-fib

• b) Defining ECG Criteria:
• Rate:       Cannot be determined; no recognizable P, QRS, or T waves. Baseline undulations btwn
• 150-500/min

Rhythm:     Indeterminate; pattern of up (peak) and down (trough) deflections

Amplitude:     Measured from peak-to-trough

• Fine V-Fib:     Peak-to-trough   2 to < 5mm
• (rhythm difficult to distinguish from asystole)

Moderate V-Fib:   Peak-to-trough  5 to < 10mm

Coarse  V-Fib:   Peak-to-trough  10 to <15mm

Very Coarse V-fib:   Peak-to-trough  >15mm

• a) Pulseless Electrical Activity (PEA)
• b) Defining ECG Criteria:

•   Rhythm displays organized electrical activity (not VF/pulseless VT)

  Seldom as organized as normal sinus rhythm

  Can be narrow (QRS <0.10 mm) or wide (QRS >0.12 mm); fast (>100 beats/min) or slow(<60 beats/min)

  Most frequently: fast and narrow (noncardiac etiology) or slow and wide (cardiac etiology)

• a) Ventricular Asystole
• b) Defining ECG Criteria:

• Rate: no ventricular activity seen or ≤6/min; so-called “P-wave asystole” occurs with only atrial impulses present to form P waves

Rhythm: no ventricular activity seen; or ≤6/min

PR: cannot be determined; occasionally P wave seen, but by definition R wave must be absent

QRS complex: no deflections seen that are consistent with a QRS complex

a) Sinus Tachycardia (a type of supraventricular tachyarythmia or SVT)

• b) Defining ECG Criteria:
• Rate: > 100 beats/min (note: 2.5 boxes per R-R interval, 300/2.5 = 120)
• Rhythm: sinus
• PR: usually < 0.20 sec
• P for every QRS Complex
• QRS complex: May be normal or wide if there is an underlying abnormality

a) Atrial Fibrilation

• b) Defining ECG Criteria:
• *  
Rate:  Wide-ranging ventricular response to atrial rate of 300-400 beats/min
• *  Rhythm:  Irregular (classic “irregularly irregular”)P waves: Chaotic atrial fibrillatory waves only; Creates disturbed baseline
• *  PR:  cannot be measured
• *  QRS complex:  Remains ≤0.10-0.12 sec unless QRS complex distorted by fibrillation/flutter waves or by conduction defects through ventricles

a) Atrial Flutter

• b) Defining ECG Criteria:

•   Rate:   
•     * Atrial rate 220-350 beats/min                 
•     * Ventricular response = a function of AV node block or conduction of atrial impulses    
•     * Ventricular response rarely >150-180 beats because of AV node conduction limits
•   Rhythm: 
•     * Regular (unlike atrial fibrillation)   
•     * Ventricular rhythm often regular   
•     *  Set ratio to atrial rhythm, eg, 2-to-1 or 3-to-1
•   P waves: 
• No true P waves seen; Flutter waves in “sawtooth pattern” is classic
•   PR: cannot be measured
•   QRS complex:  Remains ≤0.10-0.12 sec unless QRS complex distorted by fibrillation/flutter waves or by conduction defects through ventricles

a) Sinus rhythm with a reentry supraventricular tachycardia (SVT)

b) Reentry phenomenon; Accessory Mediated SVT may include AV nodal reentrant tachycardia or AV reentry tachycardia

• c) Defining ECG Criteria:
• Rate:  Exceeds upper limit of sinus tachycardia at rest (>220 bpm), seldom < 150 bpm, often up to 250 bpm
• Rhythm:  Regular
• P waves:  Seldom seen because rapid rate causes P wave to be "hidden" in preceding T waves or to be difficult to detect because the origin is low in the atrium
• QRS:  normal, narrow

a) Monomorphic Ventricular Tachycardia (VT)

• b) Defining ECG Criteria:
•   Rate:  ventricular rate >100 bpm; typically 120 to 250 bpm
•   Rhythm:  no atrial activity seen, only regular ventricular
•   PR:  none
•   P waves:  seldom seen but present; VT is a form of AV dissociation (which is a definingcharacteristic for wide-complex tachycardias of ventricular origin vs supraventricular tachycardiaswith aberrant conduction)
•   QRS:  wide and bizarre, “PVC-like” complexes >0.12 sec, with large T wave ofopposite polarity from QRS

a) Polymorphic V-Tach

• b) Defining ECG Criteria:
•   Rate: ventricular rate >100 bpm; typically 120 to 250
•   Rhythm:  regular or irregular ventricular, no atrial activity
•   PR:  nonexistent
•   P waves: seldom seen but present, VT is a form of AV dissociation
•   QRS:  marked variation and inconsistency seen in the QRS complexes

• a) Tordades de points: a unique type of Polymorphic VT that occurs in the presence of a long QT interval
• QRS changes in shape, amplitude, & width and appears to "twist" around the isoelectric line in a "spindle-node" pattern in which ventricular amplitude increases then decreases in a regular pattern (creating the "spindle")
• A, Start of a "spindle."  Note negative initial deflection and increasing QRS amplitude.
• B, End of a spindle and start of a "node"
• C, End of a node and start of the next spindle. Note the positive initial deflection and "spindling" in QRS amplitude

• b) Defining ECG Criteria:
•   Atrial Rate: cannot be determinied
•   Ventricular rate: 150-250 complexes per minute
•   Rhythm: only irregular ventricular rhythm
•   PR: Nonexistent
•   QRS complexes: display classic spindle-node pattern

a) Sinus Bradycardia with borderline first-degree AV block

• b) Defining ECG Criteria:

•   Rate:  < 60 bpm
•   Rhythm:  regular sinus
•   PR:  regular, 0.12 to 0.20 sec
•   QRS complex:  narrow;  <0.12 sec (often <0.11 sec) in absence of intraventricular conduction defect

a) First-Degree AV Block

• b) Defining ECG Criteria:
•   Rate:  1st-degree AV block can be seen with rhythms: sinus bradycardia, sinus tachycardia, or normal sinus mechanism
•   Rhythm: sinus, regular, both atria and ventricles
•   PR: prolonged, > 0.20 sec, but does not vary (fixed)
•   P waves:
•     * size and shape normal
•     * every P wave is followed by a QRS complex
•     * every QRS complex is preceded by P wave
•   QRS complex:  narrow, < 0.12 sec in absence of intraventricular conduction defect

a) Type I Second-Degree AV Block (Mobitz I-Wenckebach)

• b) Defining ECG Criteria:
•   Rate:  atrial rate just slightly faster than ventricular (because of dropped conduction); usually within normal range
•   Rhythm: 
•     * atrial complexes are regular & ventricular complexs are irregular in timing (because of dropped beats)
•     * can show regular P waves marching through irregular QRS
•   PR:  progressive lengthening of PR interval occurs from cycle to cycle; then one P wave is not followed by QRS complex ("dropped beat")
•   P waves:  size & shape remain normal; occasional P wave not followed by QRS complex ("dropped beat")
•   QRS complex:  <0.12 sec most often, but a QRS "drops out" periodically

a) Type II Second-Degree AV Block (Infranodal; Mobitz II; Non-Wenckebach) - High Block

• b) Defining ECG Criteria:
•   Atrial Rate:  usually 60-100 bpm
•   Ventricular Rate:  by definition (due to blocked impulses) slower than atrial rate
•   Rhythm:
•     * Atrial is regular
•     * Ventricular is irregular (bc of blocked impulses), but was regular until dropped beats
•     * Ventricular is regular if there is consistent 2:1 or 3:1 block
•   PR: 
•     * constant and set
•     * no progressive prolongation some P waves will not be conducted & therefore not followed by a QRS complex
•   P waves: 
•     * typical in size & shape
•     * by definition some P-waves will not be conducted & therefore not followed by a QRS complex
•   QRS complex: 
•     * narrow (<0.12 sec) implies high block relative to AV node
•     * wide ( 0.12 sec) implies low block relative to AV node

a) Type II Second-Degree AV Block (Infranodal; Mobitz II; Non-Wenckebach) - Low Block

• b) Defining ECG Criteria:
•   Atrial Rate:  usually 60-100 bpm
•   Ventricular Rate:  by definition (due to blocked impulses) slower than atrial rate
•   Rhythm:
•     * Atrial is regular
•     * Ventricular may be irregular (bc of blocked impulses) or regular if there is consistent 2:1 or 3:1 block
•     * In this case: PR-QRS intervals are regular until 2 dropped beats occur
•   PR: 
•     * constant and set
•     * no progressive prolongation some P waves will not be conducted & therefore not followed by a QRS complex
•   P waves: 
•     * typical in size & shape
•     * by definition some P-waves will not be conducted & therefore not followed by a QRS complex
•   QRS complex: 
•     * narrow (<0.12 sec) implies high block relative to AV node
•     * wide ( 0.12 sec) implies low block relative to AV node

• a) Third-Degree AV Block with a junctional escape pacemaker
• Pathophys: 3-degree block causes atria & ventricles to depolarize independently w/no relationship between the two (AV dissociation)

• b) Defining ECG Criteria:
•   Atrial rate: 
•     * usually 60-100 bpm
•     * impulses completely independent ("dissociated") from the slower ventricular rate
•   Ventricular rate:
•     * depends on rate of ventricular escape beats that arise
•     * ventricular escape rate slower than atrial rate = 3rd-degree AV block (rate = 20 to 40 bpm)
•     * ventricular escape rate faster than atrial rate = AV dissociation (rate = 40 to 55 bpm)
•   Rhythm:  both atrial & ventricular rhythm are regular but independent ("dissociated")
•   PR: by definition there is no relationship between P wave and R wave
•   QRS complex:
•     * narrow (< 0.12 sec) implies high block relative to AV node

• 5 H's:
•   Hypovolemia
•   Hypoxia
•   Hydrogen ion (acidosis)
•   Hypo-/hyperkalemia
•   Hypothermia

• 5 T's:
•   Tension pneumothorax
•   Tamponade, cardiac
•   Toxins
•   Thrombosis, pulmonary
•   Thrombosis, coronary

1) They vasoconstrict blood vessels

2) Vasopressors optimize cardiac output & blood pressure; evidence that use of vasopressors favors initial resuscitation with ROSC (return of spontaneous circulation)

• 1) Vasopressors given during cardiac arrest:
•   Epinephrine: 1 mg IV/IO (repeat q 3-5 min)
•   Vasopressin: 1 dose of 40 units IV/IO (may replace either first or second dose of epinephrine)

• 2) Epinephrine stimulates adrenergic receptors, causing vasoconstriction.
• Vasopressin stimulates non adrenergic peripheral  receptors

3) The efficacy of Vasopressin is no different from Epinephrine in cardiac arrest.

Administer Epinephrine every 3-5 minutes after the dose of Vasopressin if there is a continuing need for a vasopressor.

No, however, Amiodarone has been shown to increase short-term survival to hospital admission when compared with placebo or lidocaine.

1. Amiodarone

2. Lidocaine

3. Magnesium Sulfate

• A:
• 1) Shout for help/ Activate Emergency Response
• 2) Start CPR
• 2) Give O2
• 3) Attach monitor/defibrillator

• B: This indicates no shockable rhythm
• 1) CPR 2 min (30 compressions)
• 2) IV/IO access
• 3) Epinephrine q 3-5 min
• 4) Consider advanced airway
• 5) If still not shockable -> CPR 2 min & treat reversible causes;  If shockable, go to C.

• C: These are shockable rhythms
• 1) SHOCK
• 2) CPR 2 min
•      * IV/IO access
• 3) SHOCK (if VF/VT)
• 4) CPR 2 min
•      * Epinephrine 1 mg q 3-5 min (or Vasopressin 40 units)
•      * Consider advanced airway, capnography
• 5 SHOCK (if VF/VT)
• 6) CPR 2 min
•      * Amiodarone 1st dose: 300 mg bolus
•      * Treat reversible causes
• 7) If VF/VT continues: SHOCK -> CPR -> Epi -> SHOCK -> CPR -> Amiodarone 2nd dose 150 mg

• 1. Optimize ventilation & oxygenation
•   Maintain O2 sat 94%
•   Consider advanced airway & waveform capnography
•   Do not hyperventilate (10-12 breaths/min)

• 2. Treat hypotension (SBP < 90 mmHg)
•   IV/IO bolus (1-2 L NS or LR; 4C if induce hypothermia)
•   Vasopressor infusion
•      -  Epinephrine IV 0.1-0.5 mcg/kg/min
•      -  Dopamine IV 5-10 mcg/kg/min
•      -  Norepinephrine IV 0.1-0.5 mcg/kg/min

• 3. Follows commands: No = Induce hypothermia
• Follows commands: Yes = Coronary reperfusion with PCI (percutaneous coronary intervention) bc likely STEMI

4. Institute glycemic control & advanced critical care

• A. If signs and symptoms include:
•   Hypotension (BP < 50)
•   Acutely altered mental status
•   Signs of shock
•   Ischemic chest discomfort
•   Acute heart failure

• B. Treatment includes:
•   Identify & treat underlying cause
•      - Maintain patent airway
•      - O2 (if hypoxemic)
•      - Cardiac monitor to i.d. rhythm; monitor blood pressure & oximetry
•      - IV access
•      - 12-Lead ECG if available; don't delay therapy
• (if symptoms occur):
•   Atropine IV (1st dose 0.5 mg; repeat q 3-5min; MAX 3 mg)

• (if atropine ineffective):
•   Transcutaneous pacing
• or
•   Dopamine IV (2-10 mcg/kg/min)
• or
•   Epinephrine IV (2-10 mcg/kg/min)

• Then:
•   Consider expert consultation or transvenous pacing

• 1) Identify & treat underlying cause:   
•     - Maintain patent airway    
•     - O2 (if hypoxemic)   
•     - Cardiac monitor to i.d. rhythm; monitor blood pressure & oximetry

• 2) GIVE:  Synchronized Cardioversion, initial doses:    
• - Narrow reg: 50-100 J    
• - Narrow irregular: 120-200 J biphasic or 200 J monophasic   
• - Wide regular: 100 J    
• - Wide irregular: defibrillation dose (NOT synchronized)

• 1) Identify & treat underlying cause:
•      - Maintain patent airway
•      - O2 (if hypoxemic)
•      - Cardiac monitor to i.d. rhythm; monitor blood pressure & oximetry

• 2) If no sxs, but QRS is wide (>0.12 sec)
• GIVE:
•      - IV access & 12-lead ECG
•      - consider Adenosine IV only if regular & monomorphic (1st dose 150 mg over 10 min; repeat if VT; follow w/maintenance 1 mg/min for 1st 6 hrs)
•      - consider Antiarrhythmic drug:
•             * Procainamide IV (20-50mg/min; Maintenance 1-4 mg)
•             * Amiodarone IV (150 mg over 10 min; Maintenance 1 mg/min for 1st 6 hrs)
•             * Sotalol IV (100 mg or 1.5 mg/kg over 5 min)

• 3) If no sxs, but QRS is NOT wide (<0.12 sec)
• GIVE:
•       - IV access & 12-lead ECG
•      - Vagal maneuvers
•      - consider Adenosine IV only if regular (1st dose 6 mg rapid IV push; follow w/ NS flush; 2nd dose 12 mg)
•      - B-Blocker or Calcium channel blocker
•      - consider expert consultation

0.5 mg

Amiodarone 300 mg

a) Complete AV block with a ventricular escape pacemaker

• b)
• QRS: wide, 0.12 to 0.14 sec
•     * wide ( > 0.12 sec) implies low block relative to AV node

1) if O2 sat < 94%, start O2 at 4 L/min, titrate

2) Aspirin 160 to 325 mg (if not given by EMS)

3) Nitroglycerin sublingual or spray

4) Morpine IV if discomfort not relieved by nitroglycerin

1) Monitor, support ABCs. Be prepared to give CPR & defibrillation.

2) Admin aspirin and consider O2, nitroglycerin, & morphine if needed

• 3) Obtain 12 lead ECG;  if ST elevation:
•      * Notify receiving hospital w/transmission or interpretaion
•      * Note time of onset & 1st medical contact

4) Notified hospital should mobilize hospital resources to respond to STEMI

5) If considering prehospital fibrinolysis, use fibrinolytic checklist

1) Check VS; evaluate O2 sat

2) Establish IV access

3) Perform brief, targeted history, physical exam

4) Review/complete fibrinolytic checklist; check contraindications

5) Obtain initial cardiac marker levels, initial electrolyte & coagulation studies

6) Obtain portable chest x-ray (<30 min)