6. SINUS RHYTHM
Regular rhythm.
Normal P wave
morphology and axis
(upright in I and II,
inverted in aVR).
Narrow QRS complexes
(< 100 ms wide).
Each P wave is followed
by a QRS complex.
The PR interval is
constant. ( P-R interval
< 0.2sec )
7. ECG INTERVALS
INTERVALS NORMAL DURATION EVENTS ON HEART
DURING INTERVALS
PR INTERVAL 0.12-0.20s (3-5 small
squares)
Atrial depolarization and
conduction through AV
node
QRS INTERVAL <0.12s Ventricular depolarization
and atrial repolarization
QT INTERVAL 0.38 – 0.42s Ventricular depolarization
plus ventricular
repolarization
ST INTERVAL (QT - QRS) -Measured from J Point to
end of the T Wave,
represents the
repolarisation of the
ventricular tissue
-Usually isoelectric
1. Elevation (>1mm)
2. Horizontal/isoelectric
3. Depression (>0.5mm)
Ventricular repolarization
8. THE J POINT
• J point – where the QRS
complex and ST segment
meet
• ST segment elevation -
evaluated 0.04 seconds
(one small box) after J
point
14. 1. VENTRICULAR FIBRILLATION
Chaotic irregular deflections of varying
amplitude.
No identifiable P waves, QRS complexes,
or T waves.
Rate 150 to 500 per minute.
Amplitude decreases with duration (coarse
VF-> fine VF).
18. 3. PULSELESS ELECTRICAL ACTIVITY
(PEA)
Organized electrical activity other than VT with absence of pulse
Pathophysiology:
Cardiac conduction impulses occurs in organized pattern but this fails to
produce myocardial contraction ; or insufficient ventricular filling during
diastole ; or ineffective contraction.
24. TACHYARRYTHMIAS
Rhythm with heart rate >100 bpm
Has many potential causes
May be symptomatic or asymptomatic
The key management is to determine whether pulses are present or not
If pulses are present, determine whether the patient is stable or unstable
Tachycardia is HR > 100 beats/minute
Tachyarrhythmia normally seen when HR > 150 beats/minute
25. SINUS
TACHYCARDIA
Heart rate > 100 bpm.
Regular rhythm.
P wave for every normal QRS complex
P waves may be hidden within each preceding
T wave at higher rate.
29. ATRIAL FLUTTER
Rhythm can be regular or variable.
Rapid identical undulating waves.
No P waves.
Sawtooth appearance known as flutter waves.
31. ATRIAL FIBRILLATION
Irregularly irregular rhythm.
No P waves.
Absence of an isoelectric baseline.
Variable ventricular rate.
QRS complexes usually < 120 ms.
Fibrillatory waves may mimic P waves leading to misdiagnosis.
40. FIRST-DEGREE AV BLOCK
PR interval >200ms (five small squares).
Sinus rhythm.
Normal P wave followed by normal QRS complex.
‘Marked’ first degree block if PR interval > 300ms.
42. SECOND-DEGREE AV BLOCK MOBITZ TYPE
I (WENKEBACH)
Progressive prolongation of the PR interval culminating in a non-conducted P
wave.
The PR interval is longest immediately before the dropped beat.
The PR interval is shortest immediately after the dropped beat.
44. SECOND-DEGREE AV BLOCK MOBITZ TYPE
II
Intermittent non-conducted P waves without progressive prolongation of
thePR interval (compare this to Mobitz I).
The PR interval in the conducted beats remains constant.
The P waves ‘march through’ at a constant rate.
The RR interval surrounding the dropped beat(s) is an exact multiple of
thepreceding RR interval (e.g. double the preceding RR interval for a
singledropped beat, treble for two dropped beats, etc).
46. THIRD-DEGREE AV BLOCK
In complete heart block, there is complete absence of AV conduction – noneof
the supraventricular impulses are conducted to the ventricles.
Atrial and ventricular rate regular but indipendently dissociated.
The P wave is normal.
47.
48. DRUGS IN RESUSCITATION
DRUG INDICATIONS DOSE AND ADMINISTRATION SIDE EFFECT AND
PRECAUTIONS
ADRENALINE • Cardiac arrest
• Symptomatic bradycardia
<40bpm
• Severe hypotension
• Anaphylaxis
• IV/IO: 1mg ( 1 ml 1:1000 ),
administered every 3-
5minutes followed by 20ml
flush
• For Anaphylactic Shock
• Severe Hypertension
• Tachyarrhythmias
• Tissue necrosis if
extravasation occurs
ATROPINE • First line drug for
symptomatic Bradycardia
• Organophosphate
poisoningSide
• The recommended dose for
bradycardia is 0.5mg IV
every 3 to 5 minutes to
amax total dose of 3mg•
• Use atropine cautiously
in the presenceof acute
coronary ischemia or
MI;increased heart rate
may worsen ischemiaor
increase infarction size.
49. DRUGS IN RESUSCITATION
DRUG INDICATIONS DOSE AND ADMINISTRATION SIDE EFFECT AND
PRECAUTIONS
ADENOSINE • First drug for most form
of stable narrow-
complex PSVT
• Give 6 mg adenosine as a rapid IV
push followed by a 20mL saline flush.
If unsuccessful, this can be followed
with up to two doses each of 12mg
every 1-2 minutes
• Transient unpleasant
side effects, in
particular nausea,
flushing, and chest
discomfort
• Caution if need to be
given in asthmatic
patient
AMIODARONE • Refractory pulseless
VT/VF ( persistent after
at least 3 shock and
adrenaline )
• Unstable
tachyarrhythmias
(failed3x cardioversion )
• Stable tachyarrhythmias
• Refractory pulseless VT /VF ; IV/IO
300mg bolus (dilute in 20mL Dextrose
5% solution) Can repeat after the 5th
shock :150 mg
• Unstable tachyarrhythmias; 300mg IV
over 10-20 minutes
• Stable tachyarrhythmias; 300mg IV
over 20-60 minutes
• Maintenance infusion; 900 mg IV over
24h
• hypotension,
bradycardia and heart
block
50. DRUGS IN RESUSCITATION
DRUG INDICATIONS DOSE AND
ADMINISTRATION
SIDE EFFECT AND
PRECAUTIONS
CALCIUM Only in Pulseless
Electrical Activity caused
by
• hyperkalaemia
• hypocalcaemia
• overdose of calcium
channel blocker
• The initial dose of 10
ml 10% calcium
chloride (6.8 mmol
Ca2+) may be repeated
if necessary
• Calcium can slow heart
rate and precipitate
arrhythmias
• In cardiac arrest,
calcium may be given
by rapid intravenous
injection
LIGNOCAINE Alternative to amiodarone
in cardiac arrest from
VT/VF
Stable monomorphic VT
with preserved ventricular
function
Cardiac arrest from VT/VF
Initial dose:1-1.5mg/kg IV
or IO
For refractory VF: may
give additional dose 0.5-
0.75mg/kg and repeat 5-
10 minutes up to 3 times
or maximal dose of
3mg/kg
In overdose it can cause
slurred speech, altered
consciousness, muscle
twitching and seizure
It also can cause
hypotension, bradycardia,
heart block and
asytoleAdvanced
51. DRUGS IN RESUSCITATION
DRUG INDICATIONS DOSE AND ADMINISTRATION SIDE EFFECT AND
PRECAUTIONS
DOPAMINE • Second-line drug for
symptomatic
bradycardia
• Use for hypotension
• Usual infusion rate is 2-
20μg/kg/minute and dose titrated
according to response
• Can cause tachycardia,
hypertension
• Can precipitate
arrhythmias
MAGNESIUM • Torsades de pointes
• Hypomagnesemia
• Cardiac arrest due to Torsades de
pointes or hypomagnesemia: 1-2g
diluted in 10 mL D5% to be givenover
5-20 minutes
• Torsades de pointes with pulse or
AMI with hypomagnesemia: Loading
dose of 1-2g mixed with 50 mLD5%
over 5-60 minute, followed with 0.5
to 1g/hour (titrate to control
Torsades)
• Occasional fall in blood
pressure with rapid
administration
52. DRUGS IN RESUSCITATION
DRUG INDICATIONS DOSE AND
ADMINISTRATION
SIDE EFFECT AND
PRECAUTIONS
VERAPAMIL • Used for narrow-
complex paroxysymal
SVT (unconverted by
vagal maneuvers or
adenosine )
• Arrhythmias known
with certainty to be of
supraventricular origin
• 2.5– 5 mg IV over 2
min: repeated doses 5-
10 mg every 15-30 min
to a maximum 20 mg
• If given to patient with
ventricular tachycardia
may cause
cardiovascular collapse
SODIUM BICARBONATE • Known prexisting
hyperkalemia
• Known preexisting
bicarbonate responsive
acidosis e.g. : aspirin
overdose, diabetic
ketoacidosis, tricyclic
antidepressant or
cocaine
• 1 mEq/kg IV bolus • May cause tissue
necrosis if
extravasation occurs
• Do not administer
together with IV line
used for vasopressors
or Calcium
53. DRUGS IN RESUSCITATION
DRUG INDICATIONS DOSE AND
ADMINISTRATION
SIDE EFFECT AND
PRECAUTIONS
DOBUTAMINE • In hypotension with
poor output state
• With present of
pulmonary oedema and
hypotension prevents
the use of other
vasodilators
• 5– 20 mcg/kg/min as
continuous infusion
• May worsen
hypotension especially
at the initial
treatment.
• Can increase risk of
arrhythmia, including
fatal arrhythmias
NOREADRENALINE • Used for hypotension
in post resuscitation
period
• Cardiogenic shock
• 0.05– 1mcg/kg/min as
continuous infusion
• Cause tissue necrosis if
extravasation occurs
• Do not administer
Sodium Bicarbonate
• through the same IV
line containing
• Noradrenaline
54. TRANSCUTANEOUS PACING
Explain and consent
IV sedation and analgesia, oxygenation
Attach self adhesive pacing pad
Set pacing mode:
FIXED MODE: deliver a fixed number of beats regardless of patient’s
intrinsic heart rate
DEMAND MODE: only deliver beats when patient’s heart rate falls below
the heart rate
Set heart rate about 60-70 beats/minute
Set current output level to minimum setting
Turn pacer ON
Note presence of pacing spike
Increase current slowly
55. Watch for electrical capture:
Pacing spikes followed by a broad QRS complex with T waves
Check for mechanical capture: palpable pulse with broad QRS complex
56. DEFIBRILLATION VS SYNCHRONIZED
CARDIOVERSION
DEFIBRILLATION
The passage of an electrical
current across the myocardium to
depolarise a critical mass of
myocardium and enable restoration
of coordinated electrical activity
Aims to restore sinus rhythm
Indicated only for VF or pulseless
ventricular tachycardia (pVT)
SYNCHRONIZED
CARDIOVERSION
Deliver shock at the peak of QRS
complex (highest point of R wave)
Deliver lower energy than
defibrillation
Can avoid delivery of shock during
cardiac repolarization (T wave)
which can precipitate VF.
Remember: low-energy shock
should always be delivered as
synchronized shock to avoid
precipitating VF
57. DEFIBRILLATION VS SYNCHRONIZED
CARDIOVERSION
DEFIBRILLATION CARDIOVERSION
Not synchronized Synchronized on the R wave
For cardiac arrest For periarrest tachyarrythmias
(unstable)
Higher energy joules Lower energy joules
No escalating energy for next
shock
Escalate energy for next shock
(100 – 200 – 300 – 360J)
58. REFERENCES
Advanced Life Support – Training Manual by MOH 2017
Guidelines for Resuscitation Training in Ministry of Health Malaysia Hospitals
and Healthcare Facilities
Tintinalli Emergency Medicine (8th edition 2015)
