See our page on haemostasis to understand anticoagulants and where they work on the haemostasis pathway. Antiplatelets are covered in a separate article. Classification of anticoagulants Drugs that block the extrinsic pathway – warfarin Drugs that block the common and intrinsic pathway – heparins Direct thrombin inhibitors – Dabigatran, bivalirudin Factor Xa inhibitors – Apixaban,…
Category: Pharmacology
Pharmacology: Antiplatelet agents
See our physiology of haemostasis page to understand how platelets work to form clots and why blocking ADP and glycoprotein IIb/IIIa can be helpful. Antiplatelet drugs: COX 1 inhibition (aspirin) Platelet phosphodiesterase inhibition (dipyridamole) ADP binding inhibition (clopidogrel, prasugrel, ticagrelor) Glycoprotein IIb/IIIa receptor antagonists (abciximab, eptifibatide, tirofiban) Dextran 70 Epoprostenol (Prostacyclin PGI2) Aspirin Uses: Analgesia,…
Physiology: Haemostasis
Antihaemostasis mechanisms – to prevent clotting in normal physiology Vascular endothelium produces a variety of factors to stop clotting in these 3 ways: Inhibit platelet adhesion Natural anticoagulants Fibrinolytic effects Inhibit platelet adhesion: Nitric oxide Prostacyclin (PGI2) Adenosine diphosphatase which degrades ADP, an essential compound for platelet activation Natural anticoagulants: Heparan sulphate (similar to heparin)…
Pharmacology: Drugs used for secondary prevention
Contents: Coronary artery disease cribsheet Secondary prevention in a nutshell ACEi/ARB Dual anti platelet therapy advice Beta blockers Statins Aldosterone antagonists References Check out our coronary artery disease crib sheet: Secondary prevention in a nutshell: After acute MI, NICE guidance gives the following recommendations for secondary prevention (CG172 published Nov 2013): Cardiac rehabilitation programme including…
Pharmacology: Volatile agents
Contents: How do anaesthetic agents work? MAC and oil gas partition coefficient and Meyer-Overton Hypothesis Blood gas partition coefficient Metabolism Comparison tables Ideal inhaled anaesthetic agent References How do anaesthetic agents work? Different theories – none completely explains it. Meyer Overton Hypothesis and membrane expansion theory – Lipid soluble anaesthetic agents enter the cell membranes…
Pharmacology: Nitrous oxide and Xenon
Nitrous oxide Fast facts: Method of action = N-methyl-D-aspartate receptor antagonist Manufacture = Heating ammonium nitrate to 250◦C: NH4NO3 → N2O + 2H2O. Impurities include NO, HNO3, N2, NO2, NH3, and are removed through scrubbers, water and caustic soda Appearance = Clear colourless gas, sweet smelling at room temperature Critical temperature = 36.5 degrees celcius…
Pharmacology: Drugs affecting the renin-angiotensin-aldosterone system
Physiology of RAAS Classification of drugs Direct renin inhibitors ACE inhibitors Angiotensin II receptor antagonists Aldosterone antagonists References Physiology of RAAS and angiotensin can be found here. Classification of drugs The simplest way would be to classify drugs that affect the RAAS is to divide them into drugs that inhibit renin, angiotensin converting enzyme or…
The Anaesthetic Room 