Distribution Of Calcium In The Body

Basic pharmacology of neuromuscular junction

ACh acts on N2 receptors (ligand-gated Na+/K+ receptors)

Block Na+ channels that propagate nerve impulse - local anaesthetics (lidocaine), tetrodotoxin

Inhibit ACh release - tetanus toxin, botulinum toxin

Competitive antagonists - vecuronium

N2 agonists - suxamethonium

Flaccid paralysis

Only cleared by plasma cholinesterase

Reversible anticholinesterases - edrophonium, neostigmine, physostigmine

Block activity of AChE

Diagnose and treat myasthenia gravis and treat glaucoma respectively

Irreversible anticholinesterases - organophosphates (pesticides, nerve gases)

Long-lived flaccid paralysis

Treat with pralidoxime within 10 minutes - cleaves OP-AChE complex

Haemosiderin staining

"Haemosiderin staining" describes orange/red/brown skin hyperpigmentation caused by haemosiderin (an iron-containing pigment found in blood) leaking into the skin.

Causes:

Chronic venous insufficiency (in lower legs)

Skin inflammation

Trauma e.g. wound, fracture, surgery

Pigmented purpuric dermatoses

Haemochromatosis

Haemosiderin staining may be exacerbated by anticoagulant use as this increases extravasation (leakage) of red blood cells into the skin.

See an example here.

Carpal bones mnemonic

So Long Till Pinky, Here Comes The Thumb

Scaphoid

Lunate

Triquetrum

Pisiform

Hamate

Capitate

Trapezoid

Trapezium

(going anti-clockwise in this diagram)

Cranial nerves mnemonic

On, on, on, they travelled and found Voldemort guarding very ancient horcruxes.

Olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, hypoglossal.

On - Olfactory nerve (CN I)

On - Optic nerve (CN II)

On - Oculomotor nerve (CN III)

They - Trochlear nerve (CN IV)

Travelled - Trigeminal nerve (CN V)

And - Abducens nerve (CN VI)

Found - Facial nerve (CN VII)

Voldermort - Vestibulocochlear nerve (CN VIII)

Guarding - Glossopharyngeal nerve (CN IX)

Very - Vagus nerve (CN X)

Ancient - Accessory nerve (CN XI)

Horcruxes - Hypoglossal nerve (CN XII)

clearance = (urine concentration x urine volume passed over time) / plasma concentration

the only useful thing my prof ever taught me for the renal physiology portion of my physiology course is that clearance is calculated by the equation “pissing under the sun” ( C = UV/P)

I don’t know what stage of the semester you’re at right now but let someone in exam period (me) give you some advice on revision: Start early. Early as in NOW. Start now to not end up like me 

Management of acute MI

Reduce anginal pain

Morphine (+ anti-emetic)

Oxygen

Nitrate

Initiate reperfusion

Anti-platelet (aspirin, clopidogrel)

Thrombolytic (rtPA)

Primary angioplasty (PTCA)

Anticoagulant (heparin)

Protect myocardium

Beta-blocker

ACE inhibitor

Secondary prevention

Aspirin

Lipid-lowering (statin)

Lifestyle

Helpful mnemonic foe MI treatment.

Causes of Acute Pancreatitis

In the UK and US, the main causes are gallstones and alcohol.

Use the mnemonic 'I GET SMASHED':

Idiopathic

Gallstones

Ethanol

Trauma

Steroids

Mumps / Malignancy

Autoimmune

Scorpion stings

Hypercalcaemia / Hypertriglyceridaemia / Hypothermia

ERCP

Drugs (including azathioprine, mesalazine, bendroflumethiazide, furosemide, steroids, sodium valproate)

Oedema - pitting vs non-pitting

Oedema is swelling due to excess fluids in tissues.

In pitting oedema, pressing on the affected area leaves an indentation (that persists after removing the pressure). In non-pitting oedema, the area feels firm to touch and does not form indentations.

Pitting oedema:

The excess fluid is mainly composed of water

Commonly caused by heart failure, venous insufficiency, or nephrotic syndrome

Non-pitting oedema:

The excess fluid consists of water WITH protein and salts

Usually indicates a condition of the thyroid / lymphatic system

Different types:

Lymphoedema is due to a build-up of lymphatic fluid (e.g. due to a tumour blocking lymphatic flow / after removal of lymph nodes).

Myxoedema occurs in hypothyroidism and often affected the pretibial or periorbital area.

Angioedema is localised swelling of the skin and is usually due to allergic reactions. It typically affects the face, tongue, larynx, abdomen, arms, and legs. When the larynx is affected, it may affect breathing, which is an emergency!

Lipoedema is when fat accumulates in subcutaneous tissues - it usually affects the legs/buttocks and almost exclusively occurs in postpubertal females (not the same as cellulite!)

If patients present with oedema, it's always important to test if it's pitting or non-pitting as this helps to determine the cause and correct treatment!

Common ototoxic medications

"FAV Q&A"

Furosemide (and other loop diuretics) Aminoglycosides Vancomycin Quinine Aspirin