#Bias amp 2 ptt series

The aim of this study was to evaluate the effect of vitamin K1 on a wide range of coagulation assays in non-bleeding critically ill patients with spontaneously prolonged Owren PT. High levels of uncarboxylated prothrombin (also known as protein induced by vitamin K absence/antagonist-II ) have been observed in critically ill patients at both the time of admission and several days after intensive care unit (ICU) admission, which indicates that critically ill patients might benefit from vitamin K1 administration. Uncarboxylated fractions of VKDPs cannot bind calcium and are therefore unable to interact with phospholipid surfaces and specific receptors. The activity of some of the VKDPs can be estimated by measuring the levels of their respective uncarboxylated proteins, where high levels correspond to low activity. Since then, several others have been described, such as Matrix Gla protein (MGP), Growth Arrest Specific 6 protein (Gas6) and Gla Rich Protein (GRP). Osteocalcin was the first extrahepatic VKDP to be detected in the 1980s.

The vitamin K cycle has been detected in most tissues in the body, able to carboxylate several so-called extrahepatic VKDPs.

#Bias amp 2 ptt series

The discovery of vitamin K’s role in post-translational gamma-carboxylation of proteins in the 1970s resulted in the identification of the vitamin K cycle, which is a series of enzymatic modifications vitamin K undergoes in order to support carboxylation. These effects are thought to be mediated through several extrahepatic vitamin K-dependent proteins, with potential involvement in protection against cardiovascular, neurodegenerative and metabolic diseases as well as cancer. In addition to strengthening the coagulation system, vitamin K has been suggested to have beneficial pleiotropic effects that extend beyond activation of coagulation factors. To the best of our knowledge, there have not been any thorough investigations with regard to vitamin K1 administration in non-bleeding adult critically ill patients and its effects on vitamin K-dependent proteins (VKDPs) (Factor II, FVII, FIX, FX, protein C and protein S), thrombin generation assay (TGA) and rotational thromboelastometry (ROTEM). Vitamin K deficiency in hospitalized patients can be misdiagnosed as disseminated intravascular coagulopathy and vitamin K1 has been proposed to reverse prolonged PTs in non-emergent situations. Vitamin K is fundamental for coagulation as it takes part in the activation processes of some coagulation factors such as factors II, VII, IX, X, and protein C and protein S. The term vitamin K identifies a series of compounds deriving from 2-methyl-1,4-naphthoquinone. There are studies suggesting that there is a benefit in treating even mildly prolonged prothrombin times (PTs) in non-bleeding critically ill patients or prior to invasive procedures, but high-quality data is lacking and there is no consensus on the issue of treating a prolonged PT, possibly induced by a vitamin K deficiency, with intravenous vitamin K1.

Opinions differ on how laboratory signs of increased bleeding diathesis in non-bleeding patients should be treated. The decreased dp-ucMGP, and its potential positive short- and long-term non-coagulative effects, merits further research.Ĭoagulation abnormalities frequently occur in critically ill patients and affect mortality. In conclusion, the results suggest that vitamin K1 strengthens coagulation as measured by PT decrease and increases in the activity of vitamin K-dependent clotting factors and thrombin generation. Concomitantly, there were increases in thrombin generation and the activity of coagulation factors II, VII, IX and X that was only counteracted with a small increase in Protein C activity. Intravenous vitamin K1 reduced Owren PT, Quick PT, protein induced by vitamin K absence/antagonist-II and desphospho-uncarboxylated matrix Gla protein (dp-ucMGP), but not to normal levels. At both time points, we measured various vitamin K-dependent proteins and coagulation assays. Blood was drawn at baseline and at 20–28 h after vitamin K1 administration. We included critically ill non-bleeding adult patients without liver failure or anticoagulation treatment, with Owren PT > 1.2, who were prescribed intravenous vitamin K1. The aim of this study was to evaluate the effects of vitamin K1 on various vitamin K-dependent proteins in critically ill patients with prolonged Owren PT.