Assessment of the risk of bleeding in patients undergoing surgery or invasive procedures: Guidelines of the Italian Society for Haemostasis and Thrombosis (SISET).

SYNOPSIS OF RECOMMENDATIONS: The Italian Society for Thrombosis and Haemostasis (SISET: Società Italiana per lo Studio dell' Emostasi e della Trombosi) promoted the development of a series of guidelines which would adopt evidence-based medicine methodology on clinically relevant problems in the field of haemostasis and thrombosis. The objective of the present guidelines is to provide recommendations for the pre-operative and pre-procedural assessment of the bleeding risk with the aim of reducing the incidence of preventable bleeding complications and limiting laboratory tests to the those necessary. The predictive value of haemostatic tests for bleeding complications after surgery or invasive procedures has been evaluated in prospective or retrospective cohort studies only. All retrieved studies were of low methodological quality with a high potential for bias because none conducted a blinded outcome assessment. In addition, different criteria for the severity of bleeding events and different reference values of the laboratory tests were adopted. The low methodological quality limits the validity of the results of these studies. Some of the clinical queries proposed by the working group were not addressed by the studies available in the literature. The areas with evidence, although of low quality, are the following: general surgery in adults (for history, PT, APTT, platelet count and bleeding time), neurosurgery in adults (for history, PT, APTT, platelet count), adenotonsillectomy in children (for history, PT, APTT, platelet count and bleeding time), invasive procedures in adults (for PT, APTT, platelet count), dental extractions (for the bleeding time only), cataract extraction (for platelet count). No studies are available in children for major surgery other than adenotonsillectomy, neurosurgery and invasive procedures.