Cardiovascular emergencies Flashcards
(25 cards)
Why must over-oxygenation be avoided during MIs?
High levels of oxygen can cause:
Vasoconstriction
Oxygen free radicals
Which MIs can benefit from fluid therapy, why?
MIs with right ventricular involvement - fluids can increase pre-load and help the contractility
Should you wait for an ECG to give asprin?
No - can be given on clinical suspicion
What QRS width during VT would be considered narrow?
QRS<120ms (same as any other rythym)
How should you treat pulsed broad complex tachycardia, what could it be?
If regular, treat as VT until proven otherwise
Could be SVT with bundle branch block
What could irregular wide complex tachycardia be?
AF with bundle branch block
Pre-excited AF
Polymorphic VT (e.g. torsades)
What is the general management of unstable out of hospital pulsed VT?
-ABCDE approach
-Identify wide/narrow, irreulgar/regular
-Prepare for it to degenerate into pulseless VT or VF.
-Appropriate transport (PPCI/ arrhythmia centre/ local trust protocols)
-Consider RVP with advanced practitioner/ HEMS for synchronised cardioversion/ administration of amiodarone.
-Synchronising avoids the delivery of a shock during repolarisation which can induce VF (this is not within the standard scope of practice for paramedics).
For what arrythmias are vagal manouevres indicated?
Regular narrow complex pulsed tachycardias
What are irregular narrow complex pulsed tachycardias likely to be?
Atrial fibrilation
What is the difference between AVRT and AVNRT?
Atrioventricular reentrant tachycardia (AVRT) is a rhythm problem that results from an extra connection between the atria and ventricles
Atrioventricular nodal reentrant tachycardia (AVNRT) is a type of paroxysmal supraventricular tachycardia that results due to the presence of a reentry circuit within or adjacent to the AV node. Usually caused by a miss-timed ectoptic.
How does adenosine work?
Causes a block within the AV node
Inhibits adenylyl cyclase, reduces cAMP and therefore, causing hyperpolarisation by increasing Potassium efflux.
What are some examples of bradyarrythmia causes?
3rd degree/ complete heart block (or high grade AVB)
AF with slow ventricular response
Ventricular escape rhythm
Sinus bradycardia
Sick Sinus Rhythm (SSS)
What is the algorithm for bradycardia management?
What adverse features are you looking for with bradycardias?
Shock
-Organ/cerebral hypoperfusion
Syncope
Myocardial ischaemia
Heart failure
How can MIs cause bradyarrythmias?
Inferior MIs specifically can cause reduced blood flow to the AV node and therefore bradycardias
What is acute cardiogenic pulmonary oedema?
The cardiogenic form of pulmonary edema (pressure-induced) produces a non-inflammatory type of edema by the disturbance in Starling forces.
What can cause acute cardiogenic pulmonary oedema?
Cardiomyopathy/Heart failure
Heart valve problems.
Hypertension.
Inflammation of the heart muscle (myocarditis)
Congenital heart defects
Arrhythmias
How can heart valve problems cause acute cardiogenic pulmonary oedema?
Narrowing (stenosis) of the aortic or mitral heart valves or a valve that leaks or doesn’t close properly affects blood flow into the heart. A valve leak that develops suddenly might cause sudden and severe pulmonary edema.
How can hypertension cause acute cardiogenic pulmonary oedema?
Untreated or uncontrolled high blood pressure can enlarge the heart, causing cardiomyopathy, reduced cardiac output and a build up of pulmonary vein pressure and therfore pulmonary oedema
What is the paramedic management of acute cardiogenic pulmonary oedema?
Oxygen therapy
Nitrates (lower preload, lower vasoconstriction/ cause vasodilatation, reduce hydrostatic arterial pressure.)
Loop diuretics (Furosemide)
CPAP
What are some adverse affects of furosemide?
Hyponatraemia
Hypokalaemia
Hypovolaemia
Hypotension
Dehydration
Why would you want to turn off an ICD?
If it is mis-firing/firing inappropriately i.e. without sign of arrythmias on cardiac monitoring often 3x within 20 minutes.
How do you turn off an ICD?
By placing a ring magnet over the top of the ICD – you will hear an alarm to let you know it is disabled. To re-enable simply remove the magnet.
What are the STEMI ECG diagnosis criteria?
At least two contiguous leads with ST-segment elevation
≥ 2.5 mm in men < 40 years (V2 & V3),
≥2 mm in men ≥ 40 years (V2 & V3),
≥ 1.5 mm in women (V2 & V3)
or
≥ 1 mm in all other leads
(except V4/7/8/9 0.5mm)
