Pharmacology* Flashcards
What are the pharmacological actions of Adrenaline?
A naturally occurring beta and alpha adrenergic stimulant
1. Increases HR by increasing SA node firing rate (B1)
2. Increases conduction velocity through AV node (B1)
3. Increases myocardial contractility (B1)
4. Increases irritability of ventricles (Beta 1)
5. Causes bronchodilatation (B2)
6. Causes peripheral vasoconstriction (Alpha)
What are the C/I and Precautions of Adrenaline?
C/I: Hypovolaemic shock without adequate fluid replacement
Precautions: Consider reduced doses for:
1. Elderly/frail
2. Pt with cardiovascular disease
3. Pt on monoamine oxidase inhibitors
4. Higher doses may be required for pt on beta blockers
What are the side effects for Adrenaline?
Side effects:
1) sinus tachycardia
2) supraventricular arrhythmias
3) ventricular arrhythmias
4) hypertension
5) pupillary dilatation
6) may increase size of MI
7) feeling of anxiety/palpitations in conscious pt
What are onset times for Adrenaline?
IV: onset 30secs, peak 3-5mins, duration 5-10mins
IM: 30-90secs, peak 4-10mins, duration 5-10mins
What is the pharmacological action of Aspirin?
Analgesic, anti-pyretic, anti-inflammatory and anti-platelet aggregation agent
- minimise platelet aggregation and thrombus formation in order to retard progress of coronary artery thrombosis
- Inhibits synthesis of prostaglandins - anti-inflammatory actions
What are the C/I of Aspirin?
- Hypersensitivity to aspirin/salicylates
- Actively bleeding peptic ulcer
- Bleeding disorders
- Suspected dissecting aortic aneurysm
- Chest pain associated with psychostimulant OD if SBP >160
What are the precautions for Aspirin?
- Peptic ulcer
- Asthma (aspirin can induce asthma reaction)
- Pt on anticoagulants
What are the side effects for Aspirin?
Side effects:
1. Heartburn, nausea, GIT bleeding
2. Increased bleeding time
3. Hypersensitivity reactions
What are the C/I and Precautions for Ceftriaxone?
C/I: Allergy to Cephalosporin antibiotics
Prec: Allergy to Penicillin antibiotics
What are the side effects and preparation of Ceftriaxone?
Side effects: N/V, skin rash
Special notes: IV made to 10mL with sterile water administered over 2mins, IM made up to 4mL with 1% Lignocaine
What is the presentation and pharmacology of Dexamethasone?
Pres: 8mg in 2mL
Pharma: corticosteroid secreted by adrenal cortex - relieves inflammatory reactions and provides immunosuppression
What are the C/I and Precautions of Dexamethasone?
C/I: Known hypersensitivity
Prec: Solutions which are not clear or are contaminated should be discarded
What are the special notes and onset times for Dexamethasone?
Admin IV admin over 1-3mins
IV onset 30-60mins, peak 2hrs, duration 36-72hrs
Doesn’t contain antimicrobial agent, so should be used immediately and discarded
Dextrose 10%:
- Pres
- Pharma
- Special notes
- Pres: 25g in 250mL
- Pharma: slightly hypertonic crystalloid solution - composed of sugar 10% dextrose and water
- Special notes: onset 3mins, duration depends on severity of hypoglycaemic episode
What is the presentation and pharmacology of Droperidol?
Presentation: 10mg in 2mL
Pharma: dopamine antagonist - antipsychotic medication with sedative effects
What are the C/I and Precautions of Droperidol?
C/I: Nil
Prec: 1. Elderly/frail more susceptible to adverse reactions
2. Parkinson’s disease
3. Lewy body dementia
4. Long QT
What are the adverse effects of Droperidol?
CNS: oversedation, dizziness
CVS: hypotension, tachycardia, QT prolongation
Extrapyramidal Sx
What’s the presentation and pharmacology of Fentanyl?
Pres: 100mcg in 2mL or 250mcg in 1mL IN
Pharm: synthetic opioid analgesis
Actions:
CNS: depression, resp depression, dependence
CV: decrease conduction velocity through AV node
What are the onset times and pregnancy/breastfeeding notes for Droperidol?
Onset 3-10mins, peak sedation 20-30mins, duration 2-4hrs
Pregnancy/breastfeeding: only if benefits outweigh risk
What are the C/I and Precautions of Fentanyl?
C/I: 1. Hypersensitivity 2. Late second stage of labour
Prec: A HARMER (fentanyl can be a harmer)
1) Current Asthma
2) Impaired Hepatic function
3) Known Addiction to opioids
4) Resp depression eg COPD
5) Pt on MAO inhibitors
6) Elderly/frail
7) Rhinitis, rhinorrhoea or facial trauma (IN route)
What are the side effects of Fentanyl?
1) Resp depression
2) Apnoea
3) Rigidity of diaphragm and IC muscles
4) Bradycardia
What are the onset times for IV and IN Fentanyl?
IV onset immediate, peak <5mins, duration 30-60mins
IN peak 2mins
Glucagon:
- Presentation
- Side effects
- Special notes incl onset times
Presentation: 1mg (IU) in 1mL
Side effects: N/V (rare)
Special notes: pt with inadequate glycogen stores in liver may not respond to it e.g. alcoholics and malnourished
Onset 5mins, duration 25mins
Pharmacology of GTN
Vascular smooth muscle relaxant.
1) Venous dilatation - reduces preload - promotes venous pooling
2) Arterial dilatation - reduces afterload - reduces systemic vascular resistance
Above leads to: reduce myocardial O2 demand, reduce BP while maintaining coronary perfusion pressure, mild collateral coronary artery dilatation may improve blood supply to ischaemic areas of myocardium, mild tachycardia secondary to drop in BP, uterine quiescence
What are the C/I for GTN?
- BP < 100
- HR > 150
- HR < 50 (except in autonomic dysreflexia)
- Ventricular tachycardia
- PDE5 inhibitors (current/recent use) - -fil e.g. avanafil, sildenafil, vardenafil, tadalafil
- Riociguat (current use) - Rx pulmonary hypertension i.e. Adempas
What are the precautions for GTN?
- Lower doses in elderly, no previous exposure or recent MI
- Right ventricular MI or inferior STEMI with SBP < 160
- Preterm labour - concurrent use with other tocolytics (anti-contraction)
What are the side effects of GTN?
CV: hypotension, tachycardia, bradycardia
CNS: headache, dizziness, syncope
Other: skin flushing
What are the onset times of GTN?
SL: onset 1-3mins, peak 5, at least 25mins
Transdermal: onset up to 30mins, peak 2hrs, duration continually releases until removed
What is the presentation and pharmacology of Hydrocortisone?
Presentation: 100mg powder
Pharma: corticosteroid with equal gluco and mineralocorticoid effects
Hydrocortisone special notes
IV doses delivered as slow push over 30secs
- 100mg reconstitued with 2mL NaCl or water