Anticoagulants and regional

Parenteral Anticoagulant-induced prothrombin deficiency hypoprothrombinemia secondary to conditions limiting absorption or synthesis of vitamin K (eg, obstructive jaundice, biliary fistula, sprue, ulcerative colitis, celiac disease, intestinal resection, cystic fibrosis of the pancreas, regional enteritis) drug-induced hypoprothrombinemias due to interference with vitamin K metabolism (eg, antibiotics, salicylates) prophylaxis and therapy of hemorrhagic disease of the newborn. 

Inject subcutaneously or IM when possible. In older children and adults, inject IM in the upper outer quadrant of the buttocks. In infants and young children, the anterolateral aspect of the thigh or the deltoid region is preferred. When IV administration is unavoidable, inject very slowly, not exceeding 1 mg/min. Anticoagulant-induced prothrombin deficiency in adults 2.5 to 10 mg or up to 25 mg (rarely, 50 mg) initially. Determine subsequent doses by prothrombin time (PT) response or clinical condition. If in 6 to 8 hours after parenteral administration (or 12 to 48 hours after oral administration), the PT has not been shortened satisfactorily, repeat dose. If shock or excessive blood loss occurs, transfusion of blood or fresh frozen plasma may be required. 

Intra-arterial injection of thiopentone is a serious complication as crystals of the thiobarbiturate can form in the arterioles and capillaries, causing intense pain, vasoconstriction, thrombosis, and even tissue necrosis. Accidental intra-arterial injections should be treated promptly with intra-arterial administration of a vasodilator (papaverine 20 mg) and lignocaine (lidocaine) Note leave the needle/cannula in the artery), as well as a regional anaesthesia-induced sympathectomy (stellate ganglion block, brachial plexus block) and anticoagulation with intravenous heparin. The risk of ischaemic damage is much higher with a 5% solution and the use of this concentration is not recommended. 

The C=0 stretching frequency of a number of 4-hydroxy- and 4-alkoxy-coumarins, including several anticoagulant drugs, has been identified by isotopic replacement of the carbonyl carbon atom by 3C as the highest frequency band in the 1750-1550 cm-1 region. Introduction of the isotopic atom causes a reduction in the C=0 frequency of ca. 30 cm-1 (82JHC475). 

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