Principles of free flap surgery


  • S Mohanadasan University of the Witwatersrand


free flap surgery, Hagen-Poiseuille, oxygen flux equations


Free flap microsurgery plays an important role in the management of patients for whom standard surgical procedures may not have been viable. Free flap transfer can be beneficial for difficult reconstructions and large defects that cannot be treated with conventional surgical methods. However, it is a complex surgical procedure with many limitations that can be further exacerbated by anaesthetic and patient factors. Patients who are selected for this type of surgery can prove challenging for the anaesthetist to manage due to various metabolical and cancer-related systemic problems. Careful assessment of these patients preoperatively, together with multidisciplinary team (MDT) meetings, can help identify and mitigate any challenges that can be encountered in the perioperative period. Understanding the Hagen–Poiseuille and the oxygen flux equations can be beneficial in the management of free flap surgery. The use of vasopressors has been a contentious issue with no clear consensus regarding its use in free flap surgery. However, goal directed fluid therapy together with vasopressors to prevent intraoperative haemodynamic instability, can yield better outcomes than fluid therapy alone. Opioid-free analgesia (OFA) with enhanced recovery after surgery (ERAS) principles can help ensure better patient outcomes with fewer opioid-related side-effects.

Author Biography

S Mohanadasan, University of the Witwatersrand

Department of Anaesthesia, School of Clinical Medicine, Faculty of Health Sciences, Charlotte Maxeke Johannesburg Academic Hospital, University of the Witwatersrand, South Africa






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