ECG Flashcards

(295 cards)

1
Q

describe the passage of blood through the heart

A

deoxygenated blood from the body arrives from cranial vena cava
right atrium
tricuspid valve
right ventricle
pulmonary valve
pulmonary artery to the lungs
pulmonary vein from the lungs
left atrium
mitral valve
left ventricle
aortic valve
aorta to systemic circulation

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2
Q

what is the purpose of the heart beating?

A

pump blood around the body and lungs

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3
Q

what is myocardium made up of?

A

cardiac muscle

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4
Q

is heart contraction governed by nerve impulse?

A

no - contracts automatically

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5
Q

what is the process of heart contraction controlled by?

A

electrical impulses

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6
Q

what relating to the heart is controlled by the autonomic nervous system?

A

heart rate

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7
Q

what part of the nervous system controlls heart rate?

A

autonomic

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8
Q

what are the 2 branches of the autonomic nervous system?

A

sympathetic
parasympathetic

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9
Q

what effect does the sympathetic nervous system have on heart rate?

A

increases HR

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10
Q

what effect does the parasympathetic nervous system have on heart rate?

A

slows

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11
Q

how does the parasympathetic nervous system slow heart rate?

A

release of acytylcholine

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12
Q

how does the sympathetic nervous system increase heart rate?

A

releases catecholamines to accelerate HR

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13
Q

what catecholamines increase HR?

A

adrenaline
noradrenaline

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14
Q

what are the 2 types of cardiac cells?

A

electrical cells
myocardial cells

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15
Q

what is the role of electrical cells within the heart?

A

conduction system of the heart
spontaneously generate and respond to electrical impulses
transmit electrical impulses

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16
Q

how are electrical cells distributed throughout the heart?

A

orderly fashion throughout the heart

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17
Q

where are myocardial cells found?

A

within the walls of the atrium and ventricles

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18
Q

what is the role of myocardial cells?

A

responsible for contraction and stretch of the heart

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19
Q

what is required for the heart to function properly?

A

coordinated contraction of both atria and ventricles

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20
Q

what is coordinated atrioventricular contraction?

A

coordinated contraction of both atria and ventricles to expel blood into aorta and pulmonary artery

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21
Q

what do cardiac muscle cells require to contract?

A

electrical stimulus

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22
Q

what state are cardiac cells in when relaxed?

A

polarised

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23
Q

what happens to cardiac cells when stimulated by an electrical impulse?

A

cells start to depolarise

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24
Q

what area of the heart must be depolarised first in order to allow the heart to function properly?

A

two atria

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25
what part of the heart is depolarised after the atria?
ventricles
26
what must the heart do between beats?
repolarise (relax) and return to resting potential
27
why must the heart repolarise (relax) and return to resting potential between beats?
to allow appropriate filling during dyastole ready for the next contraction
28
what is the sinoatrial (SA) node?
small area of cardiac muscle cells that are specialised found in the wall of the right atrium
29
where is the SA node located?
wall of the right atrium
30
what is the role of the SA node?
initiation of heart beat
31
why is the SA node the initiator of the heart beat?
fastest area to generate electrical activity
32
what is the role of the SA node?
pacemaker of the heart controls HR
33
what is the SA node influenced by?
autonomic tone
34
what effect will increased sympathetic tone have on the SA node?
increase HR
35
what effect will increased parasympathetic tone have on the SA node?
decrease HR
36
how does the SA node lead to atrial systole?
SA node fires electrical impulse which causes depolarisation to spread through atrial muscle cells impulse spreads over atria causing both to contract
37
what is caused by creation of electrical impulse by SA node?
atrial systole
38
where is the atrioventricular (AV) node located?
top of the interventricular septum
39
what happens to the nerve impulse after it moves across the atria?
passes through AV node
40
how rapidly does the electrical impulse from the SA node spread through the AV node?
more slowly
41
what is the purpose of the slow conduction through the AV node?
slows electrical impulse before it reaches the ventricles to ensure that ventricular contraction is correctly coordinated following atrial contraction atria can fully contract before ventricles
42
is the myocardium of atrial walls in continuity with myocardium of ventricular walls?
no
43
how does electrical impulse pass from atria to ventricles?
through AV ring to bundle of His
44
what is the bundle of His?
specialised nerve tissue fibres
45
where is the bundle of His located?
interventricular septum
46
what does the bundle of His divide into?
right and left bundle branches
47
where are bundle branches found?
right and left ventricles
48
what does the left bundle branch divide into?
anterior and posterior fascicles
49
what does the bundle of His connect to?
Purkinje fibres
50
what are Purkinje fibres?
network of specialised neurons organised into fine branches
51
where are Purkinje fibres found?
spread out through the myocardium of the ventricles
52
where does the wave of depolarisation begin in the ventricles?
apex of the heart (the bottom)
53
where does the contraction of the ventricles move once initiated at the apex of the heart?
upwards through muscle of the ventricles
54
what is contraction of the ventricles known as?
ventricular systole
55
what happens once the heart cells repolarise?
SA node fires another impulse and the cycle begins again
56
what is measured by an ECG?
changing electrical activity of the heart
57
what is used to measure electrical activity of the heart?
ECG using positive and negative electrodes
58
what is electrocardiography?
process of recording changing potential differences within the heart
59
what is the most common method of electrocardiography?
leads placed on limbs or chest
60
what is ECG essential for the diagnosis of?
cardiac rhythm disturbance
61
what is detected by an ECG machine?
depolarisation wave travelling across the heart from the SA node across the atria in the direction of the ventricles
62
what charge of electrodes does the electrical impulse of the heart travel between?
negative to positive
63
what does the ECG machine record the electrical wave as?
deflections
64
what are negative ECG deflections displayed as on an ECG machine?
downward strokes
65
what are positive ECG deflections displayed as on an ECG machine?
upward strokes
66
what is created when parts of the atria nearest the SA node are depolarised?
electrical potential difference
67
what is the electrical potential difference detected by ECG between?
depolarised atria and parts still in a resting state
68
when are ECGs used?
diagnosis of arrhythmia triage anaesthesia patient monitoring pulse deficits CPR metabolic or electrolyte abnormalities pericardiocentesis / central line placement to detect and arrhythmias caused hands off monitoring during blood transfusion
69
where are ECG leads placed?
red - right fore yellow - left fore green - left hind (black - right hind, if used)
70
what are the 2 common types of ECG electrode?
crocodile clips ECG pads
71
what position should an ECG be obtained in ideally?
right lateral
72
what needs to be removed from the area where an ECG is being performed to ensure accurate ECG reading?
anything that may create interference (e.g. mobile)
73
what are the main types of ECG equipment?
multiparameter paper-trace recording Holter monitor telemetry
74
what are papertrace ECGs used for?
diagnosis of arrhythmia
75
what are Holter monitors used for?
longer term monitoring so patient can go home
76
what should be checked if the ECG is not working?
settings battery are leads attached are leads on correct legs minimal patient movement ideally right lateral is patient panting / purring check contact and apply spirit change if not sticking clip more fur
77
what are the phases of an ECG complex?
P QRS T
78
what does the P wave represent?
atrial electrical activity
79
why are P waves small?
muscle mass of atria relatively small so associated electrical changes are also small
80
when are P waves seen?
atrial depolarisation
81
what type of deflection is atrial depolarisation wave?
+
82
what else is depolarised along with the atria?
AV node
83
what does the P-R interval represent?
time between atrial depolarisation and ventricular depolarisation
84
how is the P-R interval measured?
distance between onset of the P wave and onset of the R wave
85
what does a normal P-R interval mean?
electrical impulse is travelling at the correct speed between the atria and the ventricles
86
what happens to the depolarisation wave once it has passed through the AV node?
travels through bundle of His and Purkinjie fibres
87
what is the first part of the ventricles to depolarise?
ventricular septum
88
what is the Q wave?
small depolarisation wave seen when the ventricular septum depolarises
89
what shape is the Q wave?
downward wave (negative deflection) on the ECG trace
90
what sort of deflection is the Q wave?
negative
91
what direction does the Q wave travel?
away from the positive electrode
92
when does the R wave occur?
when the majority of the ventricles are depolarised
93
what direction does the depolarisation of the R wave travel?
towards the positive electrode creating a positive deflection
94
what is the largest wave on the EGC trace?
R wave
95
what makes the R wave the largest wave on the ECG?
large mass of tissue in the ventricles creating the largest positive deflection
96
when does the S wave occur?
following depolarisation of the majority of the ventricles
97
where does the final depolarisation of the ventricles occur?
base of the heart
98
what direction does the wave of depolarisation that forms the S wave travel in?
away from the positive electrode creating a negative deflection
99
why is the S wave small?
small tissue mass so small electrical deflection
100
what is represented by the QRS complex?
depolarisation of the ventricles followed by ventricular muscle contraction
101
what happens to the electrical potential difference once the atria are depolarised?
no longer an electrical potential difference
102
what is the PR segment?
area of the ECG between the P wave and the Q wave
103
what is occurring during the PR segment?
slow impulse conduction through the AV node
104
when does the ST segment occur?
once the ventricles are depolarised
105
what does the ST segment represent?
interval between ventricular depolarisation and repolarisation
106
what is represented by the T wave?
repolarisation of the ventricles following depolarisation and contraction
107
what does the T wave mark the beginning of?
ventricular relaxation and repolarisation
108
what is created during the T wave phase?
potential difference across the ventricular myocardium until the ventricles are completely repolarised
109
how may the T wave appear on ECG?
positive deflection negative deflection mixed deflection
110
what are the main areas to look at when interpreting an ECG?
rate all expected waves present (P, QRS,T) any arrhythmias
111
what can be assessed about the rate of ECG?
tachycardia bradycardia
112
what can be assessed about the presence of all ECG complexes?
are they all present are all complexes identical is there a P wave for every QRS and vice versa
113
what can be assessed about the presence arrhythmia on ECG?
regularly irregular regularly regular irregularly irregular intermittent or continuous sinus, ventricular or supraventricular
114
what is included within arrhythmias?
abnormailities in: rate electrical impulse conduction ectopia
115
what can cause arrhythmias to occur?
when other areas of the heart begin to generate their own electrical activity which overrides pacing of the SA node
116
what are the main sinus rhythms?
normal sinus sinus arrhythmia
117
what are the main bradyarrhythmias?
sinus bradycardia sick sinus syndrome atrioventricular beats escape beats hyperkalaemia
118
what are the main tachyarrhythmias?
sinus tachycardia supraventricular tachycardia atrial fibrillation ectopic beats accelerated idioventricular rhythm ventricular tachycardia R-on-T phenomenon
119
what are they main cardiac arrest rhythms?
ventricular fibrillation pulseless ventricular tachycardia pulseless electrical activity asystole
120
describe sinus rhythm on an ECG
P, QRS, T all present P for every QRS all complexes identical
121
what is heard on auscultation of a patient with sinus rhythm?
regular heart sounds HR normal for age, breed and species
122
are pulse deficits seen with sinus rhythm?
no
123
what does the ECG trace look like with sinus arrhythmia?
normal P for every QRS-T
124
describe sinus arrhythmia
impulse originates from SA node a regular variation in HR which coincides with respiration
125
what is sinus arrhythmia also known as?
respiratory sinus arrhythmia
126
what is sinus arrhythmia thought to be caused by?
increase in parasympathetic activity (vagal tone) on the SA node
127
when is sinus arrhythmia seen?
normal and common in dogs as long as HR in normal range rare in cats
128
what is occurring when sinus bradycardia is seen?
SA node impulse and corresponding depolarisation occurs more slowly than normal
129
describe sinus bradycardia
normal sinus rhythm P wave for every QRS-T HR inappropriately slow for age breed and species pulse for every beat regularly regular rhythm
130
what are the main causes of sinus bradycardia?
normal in some breeds (e.g. giant breeds or very fit animals) issue with SA node secondary to other disease process which increases vagal tone
131
what diseases which increase vagal tone may cause sinus bradycardia?
hypoadrenocorticism BOAS raised ICP vaso-vagal reaction hypocalcaemia hyperkalaemia hypothermia hypoglycaemia hypothyroidism
132
how is sinus bradycardia treated?
underlying cause treated anticholinergic to increase HR
133
what may be used to temporarily treat sinus bradycardia?
anticholinergic atropine or glyco
134
what may be used to treat sinus bradycardia if anticholinergic is unsuccessful?
positive inotrope
135
what are examples of positive inotropes that may be used to treat sinus bradycardia?
dopamine dobutamine
136
what is sick sinus syndrome caused by?
problem with SA node function which means there is an issue with discharge of the electrical impulse
137
what are the signs of sick sinus syndrome?
severe bradycardia (<30 bpm) may see periods of asystole for several seconds without escape beats SA node will restart but sinus arrest common
138
what is sinus arrest?
periods of asystole
139
in what animals is sick sinus syndrome seen?
older (6-10 years) common in WHWT, spaniels and schnauzers rare in cats
140
how is sick sinus syndrome treated?
pacemaker rarely responds to medical management well
141
how long do most pacemakers last for?
5-10 years
142
what are the risks associated with pacemakers?
infection lead dislodgement failure to place correctly venous thrombosis
143
what are the nursing considerations for patients with pacemakers?
no walking for 48 hours post surgery harness only care with neck restraint no jugular samples
144
what are pacemakers used to treat?
bradyarrhythmias
145
what is heart block?
problem with the electrical conduction system of the heart
146
what happens during heart block?
electrical impulses from the SA node are delayed or completely blocked from going through the AV node
147
what is the effect of delayed or blocked electrical impulses from the AV node?
electrical impulse may not reach the ventricles
148
what can AV block be caused by?
disease process drug effect at AV node
149
what are the main blocks which affect the AV node?
atrioventricular block (AV block) AV nodal block
150
what are the blocks which affect the left or right bundle branches?
bundle branch blocks
151
what happens during first degree AV block?
delayed conduction through AV node
152
what is seen on ECG with first degree AV block?
normal P and QRS complex longer interval between P and corresponding QRS complex (prolonged P-R)
153
what happens during second degree AV block?
longer conduction delay through the AV node - some impulses not transferred at all
154
how may second degree AV block appear on an ECG trace?
some P waves will not have corresponding QRS complexes QRS complexes normal in morphology
155
why are QRS complexes normal in morphology during 2nd degree AV block?
as there has been conduction through the AV node
156
what are the 2 types of 2nd degree AV block?
Mobitz type 1 (Wenckebach) Mobitz type 2
157
what does the ECG look like in Mobitz type 1 (Wenckebach) AV block?
P-R interval increases in size then a P wave will be seen without QRS following missing QRS the rhythm returns to normal
158
what does the ECG look like in Mobitz type 2 AV block?
P-R interval the same each time occasional P wave seen with no corresponding QRS complex
159
what happens during 3rd degree AV block?
complete lack of conduction through the AV node ventricular escape beats (ectopics) seen to prevent death
160
how does 3rd degree AV block appear on ECG?
multiple P waves with no QRS P waves occur faster wide and bizarre escape beats seen - have no P wave attached
161
why are ventricular escape beats seen with 3rd degree AV block?
rescue for the heart as no conduction through the AV node and so animal would otherwise die
162
how are ventricular escape beats in 3rd degree AV block caused?
radondomly generated by cardiac cells
163
what HR is seen with 3rd degree AV block?
20-40 bpm
164
what are the clinical signs of AV block?
if severe (3rd degree) there will be signs of decreased CO
165
what are the signs of decreased CO?
syncope lethargy collapse
166
how is AV block treated?
management of any underlying conditions vagolytic drugs pacemaker for severe second degree and third degree
167
what vagolytic/anticholinergic drugs may be used in AV block?
atropine glycopyrrolate
168
what arrhythmia is seen with hyperkalaemia?
bradycardia
169
what may be seen on an EGC of a patient with hyperkalaemia?
bradycardia reduced or absent P waves spiked T waves shortened QT prolonged QRS
170
what can hyperkalaemia progress to?
atrial standstill sine wave pattern v fib asystole
171
what is the normal range for potassium?
3.5-5 mmol/l
172
what are the causes of hyperkalaemia?
urethral obstruction AKI hypoadrenocorticism
173
how can hyperkalaemia be managed?
calcium gluconate bolus neutral insulin infusion dextrose infusion
174
what is the role of calcium gluconate in the management of hyperkalaemia?
reduction of risk of v fib and protection of cardiac myocytes from elevated K+
175
what is the role of neutral insulin in the management of hyperkalaemia?
causes movement of K+ into cells
176
what is the role of dextrose infusion in the management of hyperkalaemia?
causes cells to increase uptake of glucose which leads to an intracellular shift of K+ prevents hypoglycaemia due to insulin admin
177
what causes sinus tachycardia?
SA node generates an impulse and depolarisation at a rate faster than normal
178
what is seen on an ECG of a patient with sinus tachycardia?
normal sinus rhythm P-QRS-T normal regularly regular
179
what may happen to pulses with extreme sinus tachycardia?
should be synchronous may become weaker with very fast pulse rates
180
what can sinus tachycardia be caused by?
normal process (e.g. exercise) pain hypovolaemia anaemia
181
what are the 2 categories of arrhythmia?
supraventricular ventricular
182
where do supraventricular arrhythmias originate from?
atria
183
where within the atria do supraventricular arrhythmias come from?
point other than the SA node
184
how do supraventricular arrhythmias appear on ECG?
QRS relatively normal may be taller and more narrow
185
where do ventricular arrhythmias originate from?
ventricles
186
do ventricular arrhythmias follow the normal conduction pathway?
no
187
how does the ECG of a patient with ventricular arrhythmias appear?
QRS complexes are wide and bizarre
188
what has happened if the P-QRS-T complex looks different to normal?
impulse has arisen from an ectopic location
189
what does ectopic mean?
out of place (i.e. not the SA node)
190
what is occurring during ectopic beats?
beats originate from cells other than those in the SA node
191
when do ectopic beats occur in the cardiac cycle?
prematurely - interrupt normal rhythm
192
where can ectopic beats originate from?
atria or ventricles
193
what are ectopic beats classified by?
point of origin
194
what are atrial ectopic beats known as?
atrial premature complex
195
what are junctional ectopic beats known as?
junctional premature complex
196
what are ventricular ectopic beats called?
ventricular premature complex
197
what are other forms of ectopic beats?
supraventricular tachycardia escape beats seen with 3rd degree AV block
198
why are supraventricular ectopic beats called that?
originate above the SA node
199
what is caused by supraventricular ectopic beats?
heartbeat occurs earlier than expected after the last complex before the next SA node impulse
200
how would supraventricular arrhythmias appear on ECG?
abnormal P wave as not initiated by SA node QRS complex after
201
what is the rhythm like in supraventricular arrhythmia?
irregularly irregular
202
what are supraventricular arrhythmias known as?
atrial premature complex premature atrial contraction atrial premature beat
203
what is indicated by 3 or more atrial premature complexes in a row?
supraventricular tachycardia
204
what HR may be seen with supraventricular tachycardia?
170-350 bpm
205
how may supraventricular tachycardia appear on ECG?
QRS complexes narrower and more upright than normal may or may not see an associated P wave
206
what are the clinical signs of slow SVT?
often none
207
what are the clinical signs of fast SVT?
weakness collapse poor PQ poor peripheral perfusion pale MM prolonged CRT
208
why do clinical signs of SVT occur?
inadequate diastolic filling due to sort period of diastole
209
what are the causes of SVT?
often associated with underlying cardiac disease (DCM) can be associated with systemic disease such as hypovolaemia, toxicity, ischemia and electrolyte imbalances
210
how can SVT be treated?
decrease HR treat underlying cause
211
what drugs may be used for SVT?
beta blockers (Solatol / Atenolol) calcium channel blockers (Diltiazem)
212
what sort of arrhythmia is atrial fibrillation?
supraventricular tachycardia
213
what happens when the heart is in atrial fibrillation?
rapid and irregular contraction of the atria
214
in what animals is atrial fibrillation seen?
common in dogs rare in cats
215
what is the pulse like in a patient with AF?
pulse deficits irregular pulse
216
what is the HR like of a patient with AF?
rapid often >200 irregular beat with no pattern
217
what does AF appear like on ECG?
supraventricular QRS complex (taller and narrower) no visible P waves as impulse not from SA node
218
what does a heart with atrial fibrillation sound like?
trainers in a tumble dryer!
219
how is AF treated?
decrease HR increase CO calcium channel blockers beta blockers digoxin amiodarone
220
what are junctional premature complexes?
ectopic beats that arise from an area within the atrioventricular junction
221
what is the effect of junctional premature complexes arising from the region of the AV node?
ventricles usually activated normally
222
how common are JPCs?
less common than APCs or VPCs
223
how do JPCs appear on ECG?
QRS complex premature with morphology similar to sinus complexes but narrower usually without preceding P wave but this can be hidden, abnormal or premature
224
what controls ventricular contractions when ventricular arrhythmia seen?
ectopic site below the AV node an area of the ventricles becomes the pacemaker
225
why are ventricular complexes wide and bizarre on ECG?
normal electrical pathway not followed and conduction is slower
226
what are the causes of ventricular arrhythmias?
underlying primary cardiac disease (e.g. DCM) complication due to another condition (e.g. GDV, pyo, pancreatitis)
227
when do VPCs occur in the cardiac cycle?
prior to normal SA node depolarisation
228
how do VPCs appear on ECG?
no preceding P wave except by coincidence wide and bizarre QRS
229
describe pulse quality with VPCs
weak on certain beats
230
are pulse deficits seen with VPCs?
yes
231
what are VPCs also known as?
premature ventricular contractions (PVCs)
232
what is accelerated idioventricular rhythm?
3 or more VPCs together
233
what is the heart rate like with accelerated idioventricular rhythm?
not very elevated 140-180 bpm
234
how should accelerated idioventricular rhythm be managed?
generally considered benign at this rate unlikely to affect CO treatment not usually needed monitor for V tach
235
when may accelerated idioventricular rhythm be seen?
patients recovering from extensive abdominal surgery
236
what may accelerated idioventricular rhythm progress to?
VT
237
what is ventricular tachycardia?
3 or more VPCs in a row with HR of >180 bpm
238
how does VT appear on ECG?
QRS wide and bizarre absent P waves T waves large
239
what are the clinical findings in a patient with VT?
decreased CO signs of haemodynamic compromise
240
what is the pulse of a patient with VT like?
weak rapid and irregular
241
what indicates decreased CO?
hypotension collapse
242
what are signs of haemodynamic compromise?
altered mentation signs of hypoperfusion (pale MM, >CRT, hypothermia, poor PQ)
243
what are the causes of VT?
primary cardiac disease significant abdominal pathology inflammation severe anaemia abnormal autonomic activity (high sympathetic tone) electrolyte disturbances drug toxicities neoplasia
244
what can cause abnormal autonomic activity (high sympathetic tone)?
pain
245
what are the consequences of sustained VT?
cardiogenic shock decreased systemic tissue perfusion decreased cardiac perfusion myocardial failure malignant arrhythmia (VF) sudden death
246
what is the aim of treatment of VT?
convert to sinus rhythm and slow HR down to allow better CO and peripheral perfusion
247
what does treatment of VT depend on?
degree of haemodynamic compromise underlying cause
248
what are patients with underlying heart disease more likely to need if in VT?
immediate drug intervention as risk of CPA
249
what is PVT?
ventricular tachycardia with no associated pulse
250
what should be done if PVT identified?
CPR commenced immediately
251
what drugs are used to treat VT?
lidocaine beta blockers amiodarone procainamide magnesium
252
what is the most common drug used for VT?
lidocaine
253
how does lidocaine work?
sodium channel blocker
254
what is R on T phenomenon?
VPC is so premature it is superimposed on the T wave of the preceding complex can be sinus or ectopic beat
255
what happens in the ventricles during R on T phenomenon?
have not had time to completely repolarise from previous contraction before they are depolarised again
256
what makes R on T phenomenon so serious?
end of T wave is a vulnerable period anything abnormal in this time can preclude VT or VF
257
what may R on T phenomenon preclude?
VT VF
258
what is the aim of defibrillation?
high energy electric shock to the heart to reset the electrical state of the heart and convert from shockable rhythm to normal sinus
259
what is the effect of defibrillation of a non-shockable rhythm?
may be detrimental to survival
260
what are the shockable rhythms?
PVT VF
261
what are the non-shockable rhythms?
PEA asystole
262
what can VF result in?
patient death unless instantly recognised and treated
263
what occurs during VF?
no effective ventricular contraction no cardiac output so no pulse patient will be collapsed
264
how does VF appear on ECG?
rapid, irregular wavy baseline with no recognisiable normal complexes
265
what are the 2 types of VF?
course fine
266
how is VF treated?
CPR defibrillation
267
what is occurring during PEA?
electrical impulses within the heart but no corresponding contractions
268
how does PEA appear on ECG?
slow, normal or fast HR normal P-QRS-T which may become increasingly wide and bizarre
269
what is found on exam of a patient in PEA?
no audible heart beats no palpable pulses no CO
270
how is PEA treated?
CPR adrenaline and atropine check pulse concurrently only shock if converts to shockable rhythm
271
what is the most common arrest rhythm in dogs and cats?
asystole
272
how does asystole appear on ECG?
flat line no complexes
273
how is asystole treated?
CPR non-shockable rhythm
274
what disease processes is asystole associated with?
end stage disease can be caused by very high vagal tone
275
identify this ECG trace ## Footnote HR regularly irregular normal range for species
sinus arrhythmia
276
identify this ECG trace ## Footnote HR of 40
sinus bradycardia
277
identify this ECG trace
sick sinus syndrome
278
identify this ECG trace
first degree AV block
279
identify this ECG trace
second degree AV block - Mobitz type 1 / Wenckebach
280
identify this ECG trace
sinus rhythm
281
identify this ECG trace
second degree AV block (Mobitz (2))
282
identify this ECG trace
3rd degree AV block P waves Escape beats seen
283
identify this ECG trace (rhythm is faster than normal for age, breed, species)
sinus tachycardia
284
identify this ECG trace
supraventricular tachycardia
285
identify this ECG trace
Atrial fibrillation
286
identify this ECG trace
junctional premature complex
287
identify this ECG trace
ventricular premature complex
288
identify this ECG trace (rate is not very elevated - 140-180 bpm)
accelerated idioventricular rhythm
289
identify this ECG trace (HR >180 bpm)
VT
290
identify this ECG trace
R on T phenomenon
291
identify this ECG trace (no pulse palpable)
pulseless ventricular tachycardia
292
identify this ECG trace
fine VF
293
identify this ECG trace
course VF
294
identify this ECG trace (no pulse)
PEA
295
identify this ECG trace
asystole