Glycerol Trinitrate (GTN) - Nitroglycerin Flashcards
Presentation of GTN?
Sublingual spray containing 400 micrograms glycerol trinitrate per metered dose
Sublingual tablets containing glyceryl trinitrate 300, 500 or 600 micrograms per tablet
Indications of GTN?
Cardiac chest pain due to angina or myocardial infarction, when systolic blood pressure is greater than 90mmHg
Breathlessness due to pulmonary oedema in acute heart failure when systolic blood pressure is greater than 110 mmHg
Patients with suspected cocaine toxicity presenting with chest pain
What is pulmonary oedema?
a condition caused by excess fluid in the lungs
This fluid collects in the numerous air sacs in the lungs, making it difficult to breathe
Actions of GTN?
A potent vasodilator drug result in:
Dilation of coronary arteries/relief of coronary spasm
Dilation of systemic veins resulting in lower pre-load
Reduced blood pressure
Cautions of GTN?
Patients with suspected posterior myocardial infarction or right ventricular infarction
Contra-indications of GTN?
Hypotension (systolic blood pressure < 90mmHg in angina/myocardial infarction, or 110mmHg in acute heart failure)
Hypovolemia
Head trauma
Cerebral haemorrhage
Sildenafil (Viagra) and other related drugs - GTN must not be given to patients who have taken sildenafil or related drugs within the previous 24 hours. Profound hypotension may occur
Unconscious patients
Known severe aortic or mitral stenosis
What is Hypovolemia?
Also known as volume depletion or volume contraction, is a state of abnormally low extracellular fluid in the body.
Refers to the loss of extracellular fluid and should not be confused with dehydration.
What is Cerebral haemorrhage?
Intracerebral hemorrhage (ICH), also known as cerebral bleed, is a type of intracranial bleed that occurs within the brain tissue or ventricles.
What is hypotension?
Low blood pressure
What is aortic/mitral stenosis
a narrowing of the heart’s mitral valve.
This abnormal valve doesn’t open properly, blocking blood flow into the main pumping chamber of your heart
Side effects of GTN?
Headache
Dizziness
Hypotension
How long before GTN tablets must be discarded after opening?
8 weeks
How should you prevent cross contamination between patients when using GTN?
Nozzle of the spray must not come into contact with the patients mouth
Wipe after each use with a detergent wipe
Drug code for Glycerol Trinitrate
GTN
What must be moist for GTN absorption to occur?
The oral mucosa
