***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: We included four RCTs with a total of 453 participants and determined that none of these trials had overall low risk of bias. We found six ongoing trials from which we were unable to retrieve further data. Three trials provided data on mortality. Meta-analysis showed no statistical effect on overall mortality (RR 0.93, 95% CI 0.37 to 2.33; very low quality of evidence). We were unable to associate use of PCC with the number of complications probably related to the intervention (RR 0.92, 95% CI 0.78 to 1.09; very low quality of evidence). Lack of transfusion data and apparent differences in study design prevented review authors from finding a beneficial effect of PCC in reducing the volume of fresh frozen plasma (FFP) transfused to reverse the effect of vitamin K antagonist treatment. The number of new occurrences of transfusion of red blood cells (RBCs) did not seem to be associated with the use of PCC (RR 1.08, 95% CI 0.82 to 1.43; very low quality of evidence). Still, the included studies demonstrate the possibility of equally reversing vitamin K-induced coagulopathy using PCC without the need for transfusion of FFP. No effect on other predefined outcomes was observed. In the four included RCTs, use of prothrombin complex concentrate does not appear to reduce mortality or transfusion requirements but demonstrates the possibility of reversing vitamin K-induced coagulopathy without the need for transfusion of fresh frozen plasma. All included trials have high risk of bias and are underpowered to detect mortality, benefit or harm. Clinical and statistical heterogeneity is high, and definitions of clinically important outcomes such as adverse events are highly dissimilar between trials. Only weak observational evidence currently supports the use of PCC in vitamin K antagonist-treated bleeding and non-bleeding patients, and the current systematic review of RCTs does not support the routine use of PCC over FFP. Additional high-quality research is urgently needed.
Output:

In the present Cochrane systematic review, we assessed the benefits and harms of prothrombin complex concentrate in vitamin K antagonist-treated bleeding and non-bleeding patients who are undertaking acute surgical intervention. We searched the databases until 1 May 2013. We identified four randomized trials (453 participants) involving neurological and cardiac surgical settings, as well as medical reversal of vitamin K-intoxication among participants. We found six ongoing trials but were unable to retrieve these data. We reran the search in October 2014 and found one new study of potential interest. We added this study to a list of ‘Studies awaiting classification', and we will incorporate this study into the formal review findings at the time of the review update. We could not identify any beneficial effects of prothrombin complex concentrate on death. In our predefined outcomes, we identified a decreased volume of fresh frozen plasma transfused for reversal of vitamin K antagonist treatment. We could not identify statistical differences in reduced blood loss, harm or numbers of adverse events in the group treated with PCC. However, all trials were of low quality and small, and all were characterized by a high level of heterogeneity. Therefore, evidence in support of PCC in vitamin K antagonist-treated bleeding and non-bleeding patients receiving acute surgical intervention remains weak.