Factors Affecting the Risk of Free Flap Failure in Microvascular Surgery

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Microvascular free flap surgery, has become an important part of reconstructive surgery during the last decades, as it allows closure of various tissue defects and recovery of organs function. Despite surgical progress resulting in high rates of transferred tissue survival, the risk of pedicle vessels thrombosis still remains a significant problem. A total of 108 articles from Pubmed and Science Direct databases published in 2005–2015 were analysed. This review of the literature assessed the influence of patient-dependent risk factors and different perioperative management strategies on development of microvascular free flap thrombosis. Sufficient evidence for risk associated with hypercoagulation, advanced age and certain comorbidities was identified. Presently, rotational thromboelastometry allows early hypercoagulability detection, significantly changing further patient management. Identification of flap thrombosis promoting surgery-related aspects is also essential in preoperative settings. Choice of anaesthesia and postoperative analgesia, administration of different types and amounts of fluids, blood products and vasoactive agents, temperature control are no less important in perioperative anaesthesiological management. More attention should be focused on timely preoperative evaluation of patient-dependent risk factors, which can influence anaesthesiological and surgical tactics during and after microvascular free flap surgery. Perioperative anaesthesiological management strategy continues to be controversial and therefore it should be performed based on thrombotic risk assessment and patient individual needs, thus improving flap survival rates and surgical outcome.

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