sinus rhythms

Question 1

dysfunctions of the suns node can be classified as two things- what are they?

Answer 1

intrinsic (pathological changes in SA node or atrial tissue eg. age related degeneration) or extrinsic (other factors- hypothyroidism, action of antiarrythmic drugs)

Question 2

result of dysfunction of SA node causes what?

Answer 2

failure of impulse or failure of impulse spreading through atria

Question 3

what are some intrinsic causes of sinus brady ?

Answer 3

age related degeneration, ischemic heart disease, and surgical trauma

Question 4

what are some extrinsic causes of sinus brady?

Answer 4

inc parasympathetic tone (vagal tone)

Question 5

what are some causes of inc parasympathetic tone (vagal tone)

Answer 5

nausea/vomitting, valsalva maneuver, carotid pressure, MI, parasympathomimetic drugs

Question 6

what are the hemodynamic effects of extrinsic sinus brady

Answer 6

decreased SV, CO, dizziness, syncope

Question 7

treatments for extrinsic sinus brady?

Answer 7

inc hr w anticholinergic drugs (atropine) or sympathomimetic drugs (episode, dopamine)

Question 8

what are some intrinsic causes of sinus brady?

Answer 8

pain, decreased sympathetic tone, drugs

Question 9

what can cause dec sympathetic tone?

Answer 9

hypothermia, hypothyroid, hypoxia, beta blockers

Question 10

what kinds of drugs can cause dec sympathetic tone?

Answer 10

antidepressants, anesthesia, morphone, antiarrthymics, anytipsychotics

Question 11

treatment for intrinsic sinus brady?

Answer 11

pacemaker

Question 12

classification of atropine?

Answer 12

parasympatholytic (blocker). causes the heart to slow. blocking this effect allows the HR to increase.

Question 13

action of atropine?

Answer 13

prevents acetylcholine from occupying cholinergic receptor sites. suppresses vagus nerves action on SA and AV nodes- inc HR

Question 14

indications for atropine?

Answer 14

symptomatic brady, systole, pulseless electrical activity (PEA), post arrest brady

Question 15

contraindications for atropine?

Answer 15

can precipitate VF and VT in patients with severe cAD, myocardial ischemima or infarction, hypersensitivity to anticholinergic agents, tacky, narrow-angle glaucoma

Question 16

dose for atropine?

Answer 16

for brady- 0.5-1mg IV q3-5 min with a max of 3mg

can be given ET tube if no IV access

Question 17

what are some causes of inc sympathetic tone causing sinus tachy?

Answer 17

pain/anxiety,stress, fever, anemia, hypoxia, Co2 retention, hyperthyroidism, MI, CHF< hypovolemia, hypotension, allergic reactions, drugs, stimulants

Question 18

what are symptoms of sinus tacky?

Answer 18

dec SV, CO, BP, inc workload of heart, sichema, CP

Question 19

if you have symptomatic ischemic heart disease what treatment ??

Answer 19

beta blockers, Ca channel blockers

Question 20

what are some ECG clues for sinus arrhythmia?

Answer 20

p waves are irregular, R-R interval slightly irreg,

Question 21

what is sinus arrhythmia?

Answer 21

slight inc or dec in rate of sinus rhythm

Question 22

do the PR or QRS intervals change in sinus arrhythmia?

Answer 22

no

Question 23

does inspiration inc or dec sinus rhythm ? expiration?

Answer 23

inc and dec with expiration

Question 24

how can touchy vagal tone occur?

Answer 24

nausea/vomitting, morphne, inferior MIs

Question 25

what are some hemodynamic effects of sinus arrhythmia?

Answer 25

palpitations, dec BP

Question 26

how does a sinus pause/arrest/block present on an ECG?

Answer 26

p waves are absent. periods of ‘pause’

Question 27

what occurs after sinus pause/arrest/block?a

Answer 27

bradycardia and/or asystole

Question 28

what are possible causes for sinus pause/arrest/block

Answer 28

chronotropic incompetence, parasympathetic (vagal tone), hypoxia, hyperkalemia, excessive beta blockage, dig tox, quinidine tox, damage to SA node with inferior MI, myocarditiis

Question 29

what are some hemodynamic effects of sinus pause, arrest, block

Answer 29

may be asymptomatic if AV junctional pacemakers takes over

if symp: slow rate or transient systole (dec BP, CO, sissiness and syncope)

Question 30

treatments for sinus pause, arrest, block?

Answer 30

treat cause or pacemaker

Question 31

steps to ECG interpretation

Answer 31

is the rhythm regular? are there p waves for each QRS? what is the atrial rate? ventricular rate? PR interval? QRS interval? ECG rhythm? is there more than one rhythm int the strip?