CVP exam 1 study guide

CVP exam 1 study guide - Cardiovascular disease is #1 cause...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Cardiovascular disease is #1 cause of death. Major underlying cause is ischemia due to: atherosclerosis (plaquing) white thrombus red thrombus artery spasm Connective Tissue Ordinary Loose connective tissue (areolar tissue) Dense ordinary connective tissue Regular vs. Irregular Special Adipose tissue (fat) Blood cells Blood cell forming tissue Myeloid or lymphatic tissue Cartilage Bone Hemostasis Vascular Constriction associated w/ trauma, spasm trauma neural reflexes SNS induced constriction from pain local myogenic spasm responsible for most of the constriction local humoral factors thromboxane A2 from platelets Platelet Plug Platelets function as whole cells but cannot divide. They contain actin & myosin, enzymes & calcium, ADP & ATP, Thromboxane A2 (potent vasoconstrictor), Serotonin and growth factor. Inactive platelets are smooth and round but activates platelets are rigid. The platelet cell membrane contains glycoproteins that avoid the normal endothelium but adhere to the damaged area. Phospholipids containing platelet factor 3/thromboplastin initiates clotting. Platelets are important in minute ruptures. The lack of platelets is associated with small hemorrhagic areas under the skin and throughout internal tissues. Their half-life is 8-12 days - eliminated primarily by macrophage action (greater than 1/2 of all macrophages in spleen). 150,000-300,000 per l. Mechanism of Platelet Activation When platelets contact damaged area they 1) swell 2) irregular form w/ irradiating processes protruding from surface 3) contractile proteins contract causing granule release 4) secrete ADP, Thromboxane A2 & serotonin Thromboxane A2 Vasoconstrictor Potentiates the release of granule contents (not essential for release to occur)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2 Role of Endothelium The inner lining of BV and prevents platelet aggregation. Produces PGI2 (prostacyclin) {thromboxane [VC] enzyme PG12 [VD]}- vasodilator that stimulates platelet adenyl cyclase which suppresses release of granules (keeps platelets inactive) limits platelet extension. Produces factor VIII (clotting blood coagulation cascade). Anticoagulants Chelators citrate & oxalate tye up calcium (which is involved in most blood clotting steps cant get past step 3) Heparin enhances action of antithrombin III principal inhibitor of thrombin Dicumarol/Warfarin/Comoudin inhibition of vitamin K dependent factors produced by the liver hepatocytes (II, VII, IX, X). Old people w/atrial fib high chance of clot so they take this. Prostaglandin synthesis 1. Phospholipid to Arachidonic acid- Lipase 2. Arachidonic acid to PGG2-PGH2- Fatty Acid cyclooxygenase 3. PGG2-PGH2 to Thromboxane A2- Thromboxane synthase 4. PGG2-PGH2 to PGI2- Prostacyclin synthase 5. Aspirin and Ibuprofen block therefore, they prevent clotting! Block both thromboxane A2 & prostacyclin production by blocking fatty acid cyclooxygenase which
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 11

CVP exam 1 study guide - Cardiovascular disease is #1 cause...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online