Clotting abnormality

Vitamin K (phylloquinone) Helps maintain ability to form blood clots Abnormal bleeding... 

In several animal studies severe adverse effects of hypothermia were clotting abnormalities and coagulopathy (22,42). In baboons, systemic hypothermia led to increased bleeding times (43). In men the enzymatic reactions of the coagulation cascade were shown to be strongly inhibited by hypothermia (44,45). However, severe clotting abnormalities have... 

Patients with MDS (disorders of stem cells characterized by maturation defects) may die of infection or hemorrhage (due to platelet/clotting abnormalities), or their condition may progress to acute leukemia. In... 

Violi, F., Leo, R., Vezza, E., Basil , St., Cordova, C., Balsano, F. Bleeding time in patients with cirrhosis relation with degree of liver failure and clotting abnormalities. J. Hepatol. 1994 20 531 - 536... 

L-Asp has minimal effects on bone marrow and GI mucosa. Its most serious toxicities result from its antigenicity and its inhibition of protein synthesis. Hypersensitivity reactions occur in 5-20% of patients and may be fatal. These reactions are heralded by the appearance of circulating neutralizing antibody in some, but not all, hypersensitive patients. In these patients, pegaspargase is a safe alternative, and the Erwinia enzyme may be used with caution. Other toxicities result from inhibition of protein synthesis in normal tissues and include hyperglycemia due to insulin deficiency, clotting abnormalities due to deficient clotting factors, and hypoalbuminemia. 

The major disadvantages of commonly used phosphorothioates are their relatively low affinity for their target mRNA and toxic side effects, especially the immune stimulation and clotting abnormalities. Efforts to design newer compounds have yielded some with enhanced serum stability, higher target affinity, and lower toxicity (18). These molecules are discussed later in this chapter. 

Mixed backbone hybrid oligonucleotides also have been made using methylphosphonate iinkages at the ends. Methyiphosphonates are nonionic, are resistant to nucleases, but do not lead to RNase H degradation. The reduced polyanionic nature of the mixed backbone oligonucleotide with methylphosphonate moieties have the potential to reduce the clotting abnormality associated with the use of phosphorothioate agents (14). 

Bleeding time Easy, safe, accurate Painful, requires a small incision, does not identify specific clotting abnormality... 

Whatever the interventional procedure, it is vital that the patient comes to the interventional room in the best possible state to reduce risk and ensure success. Care should be taken to ensure adequate hydration to maintain renal function, and anaemia and clotting abnormalities need to be corrected. As a guide the following values should be regarded as desirable haemoglobin > 100 g/1, platelets > 50.000/ pi, PT-ratio (international normalised ratio, INR) and APTT ratio < 1.3. 

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