Anaesthetics Flashcards
Contraindication for NSAIDs
Asthma
How does the oral dose of morphine vary from the IV/IM/SC dose
Oral does is 2-3 times more
How does amitriptyline function as a analgesic and what drug category does it belong to
- Tricyclic antidepressant (TCA)
- Increases descending inhibitory signals
3 types of anticonvulsants used to treat pain and how they treat neuropathic pain
- Carbamazepine
- Sodium valproate
- Gabapentin
- Reduce abnormal firing of nerves (AKA membrane stabilisers)
Describe the WHO analgesic ladder
Step 1 (mild-moderate pain) -Non-opioids (NSAIDs + Paracetamol)
Step 2 (moderate to severe pain) -Mild opiates (e.g. codeine with/without non-opioids
Step 3 (severe pain) -Strong opioids (e.g. morphine) with/without non-opioids
Features of neuropathic pain
- Burning
- Shooting
- Numbness
- Pins + needles
- Phantom limb
How to treat mild, moderate and severe pain
- Mild = Paracetamol (+/- NSAIDs)
- Moderate = Codeine/alternative + Paracetamol (+/- NSAIDs)
- Severe = Morphine + Paracetamol (+/- NSAIDs)
Is renal support usually primary or secondary and a common reason for the need of it
- Usually primary
- Acute renal failure due to sepsis or other shock states
Who should go to ICU
- REVERSIBLE organ dysfunction/failure
- Supportive treatment to allow definitive treatment to work
- Patients who are beyond capabilities of other levels of care
Who should NOT go to ICU
- Progressive decline in chronic IRREVERSIBLE condition
- Those who will not survive
- Those will not become free of support available with the ICU (“never get off the vent”)
- Likely outcome of QOL that’s unacceptable to the patient
2 rare potential anaesthetic problems
- Malignant hyperthermia
- Cholinesterase deficiency
What is optimising in terms of pre-op care
Getting optimal medical control of pre-existing conditions (e.g. hypertension, diabetes, COPD, asthma, epilepsy, IHD)
Define one-arm brain circulation time
Time taken for the drug to travel from the site of injection (usually the arm) to the brain, where it has its effect
What is meant by minimum alveolar concentration (MAC)
- The concentration of a vapour in the lungs required prevent movement (motor response) in 50% of subjects in response to surgical (pain)
- Measure of potency
- Low no. = high potency
Define the 3 types of anaesthesia
- General, Produces insensibility to whole body, usually causing unconsciousness/coma
- Local, Applied directly to the target tissue, producing insensibility in only the relevant part of the body
- Regional, Local anaesthetic applied to nerves supplying the relevant part of the body, produces insensibility in that area/region of the body
