ICP Guidelines Flashcards
Adenosine Pharmacology
AV Node anti arrhythmic (produces transient atrioventricular nodal block)
Binds to a1 receptors in AV node, forces potassium out of the cell + prevents calcium from coming in which hyper polarises the cell
Indications Adenosine
Regular SVT (Narror complex tachycardia)
Regular SVT with aberrancy of conduction (SVT-A)
Contraindications adenosine
Hx of second or third degree heart block or sick sinus syndrome (except for pt with functioning pacemaker)
Sinus node disease
Chronic obstructive lung disease (eg asthma)
Known Hypersensitivity
Precautions Adenosine
Current dipyramole therapy (Asantin, Persantin)
Pts on carbamazepine
Amiodorone Pharmacology
A class 3 anti arrhythmic agent
Potassium channel blocker (also sodium and calcium channel blocker and beta adrenocepter blocker). Prolonged the effective refractory period interrupts the reentry circuit
Amiodorone indications
VF/ VT refractory to cardioversion
Sustained or recurrent VT
Amiodorone contraindications
VT with inadequate perfusion or in pregnancy
Known hypersensitivity to Amiodorone or Iodine
TCA overdose
Precautions Amiodorone
Nil of significance
Side effects Amiodorone
Hypotension and Bradycardia
Atropine Pharmacology
Anticholinergic agent. Inhibits actions of acytocholyne on post gangleonic cholinergic nerves
Vagal blocker - allows sympathetic effect to increase SA node firing rate and increase conduction velocity through the AV node
Atropine Indications
Bradycardia with less than adequate perfusion
Organophosphate poisoning with excessive cholinergic effects
Nerve agent poisoning
Contraindications atropine
Nil
Precautions atropine
Atrial flutter
Atrial fib
Do not increase hr over 100 (except in kids under 6)
Glaucoma
Side effects atropine
Tachycardia
Absolute contraindications to thrombolisis
Active bleeding or bleeding disorders
Severe uncontrolled BP > 180/110
Surgery or major trauma in past 6 week
GI/GU Bleeding in past 2-4 weeks
TIA/CVA in past 12 months
Prior intercranial haemorrhage
Suspected aortic dissection
Known malignant intracranial neoplasm
Relative Contraindications to Thrombolysis
Current anti coags
Traumatic or prolonged CPR >10 mins
Hx of chronic severe or uncontrolled hypertension
Advanced liver disease
Advanced metastatic cancer
Non compressible vascular puncture (eg fistula or central venous access)
Pregnancy or 1 week post partum
Magnesium Pharmacology
Magnesium acts as a smooth muscle relaxant by blocking calcium channel mediated contraction and decreasing acytocholine release.
Magnesium Indications
Torsardes de pointe
Eclampsia
Severe Preeclampsia
Pts with severe asthma unresponsive to salbutamol/ ipratroprium
Contraindications Magnesium
Known heart blocks
Known hypersensitivity
Impaired renal / hepatic function
Addison’s disease
Side effects magesium
Hypotension
Circulatory collapse
CNS and resp depression
Cardiac arrhythmias
Loss of deep tendon reflexes
Clopidogrel Pharmacology
Clopidogrel is an antiplatelet medication that inhibits platelet aggregation by irreversibly binding to the adenosine diphosphate receptor (P2Y12) on platelets, thereby preventing activation of the ADP mediated glycoprotein GP IIb/IIIa complex, which is necessary for platelet aggregation.
Enoxaparan Pharmacology
Enoxaparin is an anticoagulant medication that binds to anti-thrombin III, causing inhibition of factor Xa and factor IIa.
It is similar in structure and action to heparin. However, enoxaparin generally provides a greater safety profile and more predictable response when compared to heparin due to an increase in the ratio between anti factor Xa and anti-factor IIa.
Heparin Pharmacology
Heparin is an anticoagulant medication that inhibits the mechanisms that induce the clotting of blood and the formation of stable fibrin clots at various sites in the normal coagulation system.
When heparin combines with antithrombin III (heparin co-factor), thrombosis is blocked through inactivation of activated factor X and inhibition of prothrombin’s conversion to thrombin. This also prevents fibrin formation from fibrinogen during active thrombosis. Heparin can prevent the formation of a stable fibrin clot by inhibiting the activation of the fibrin stabilising factor.
Tenectaplase Pharmacology
Tenecteplase is a tissue plasminogen activator that works by binding to the fibrin matrix of a thrombus and converting plasminogen to plasmin. This degrades the fibrin matrix of the thrombus and helps to restore perfusion to the affected vessel.
Thrombolysis Treatment <75 No Renal Failure
Clopidogrel 300mg OR
Enoxaparan 30mg IV
Tenectaplase weight based IV
15 mins later
Enxoparan 0.1mg/kg SC (max dose 100mg)
Thrombolysis Treatment >75 No Renal Failure
Clopidogrel 300mg OR
Enoxaparan .75mg/kg SC (Max dose 75mg)
Tenecteplase half of weight based dose IV
Thrombolysis Treatment any age Renal Failure
Clopidogrel 300mg OR
Heparin 5000IU OR
Tenectaplase weight based dosage IV (half dose for >75)
15 mins later
Heparin 1000IU infusion per hour
How to prepare heparin infusion
5000 IU (1mL) into 50mL saline to make 100 IU per mL
Commence at 10 mL per hour to achieve 1000 IU per hour
Bradycardia less than adequate perfusion treatment
Atropine IV 600mcg repeat 600mcg @ 3-5 mins if required
Adrenaline infusion 5mcg per min, increase by 5mcg/min at 2 min intervals to max of 20 per min (draw up 3mg of adrenaline into 47 ml D5W)
Bolus adrenaline 5mcg intervals as required
Transcutaneous Pacing
SVT Treatment
Modified valsalva x 2
Adenosine 6mg, repeat 12 mg at 2 mins, repeat 12mg at 2 mins if required.
Sedate and cardioversion
Sedate 2mg Midaz IV, repeat 1mg IV at 2 min intervals to max of 5mg
Sync cardiovert 100j, repeat 200j
Adenosine Special considerations
Caffeine, aminophylline and theophylline block the adenosine receptors and the full incremental dosage may be required.
Carbamazepine (‘Tegretol’) can increase the level of atrioventricular block. Reduced dosage by half should be considered.
Dipyramole (a platelet aggregation inhibitor) increases the plasma levels and cardiovascular effects of Adenosine. Reducing dose by half should be considered.
Heart Transplant recipients should receive half doses.
Torsardes Treatment
Magnesium Infusion 2G over 10 mins
Repeat once at 10 mins if nil or no response