Anatomy of Free Flap Failures: Dissection of a Series

Abstract

Introduction: Free flap success rates have remained stable in recent years ranging 93% to 98%. Historically, the causes of free flap failures were attributed to the surgeon's inexperience and technique. However, there are factors beyond the surgical anastomosis that contribute to flap failure. The purpose of this study is to review each case of total flap loss in detail to develop a better understanding of complications. Methods: A retrospective study was performed over eleven years in a single surgeon's practice, a predominantly head and neck reconstructive practice. All charts were independently reviewed. In patients who sustained total flap loss, a review was conducted of patient comorbidites, anesthesia records, perioperative and follow-up notes. Results: A total of 514 free flaps were performed. 76% (392) of these flaps were for head and neck reconstruction. There were 22 total flap losses (4%) and 26 partial flap losses (5%). Of the 22 total flap losses, four flaps were avulsed, five flaps were in patients later found to have coagulation disorders (homozygous mutations of the MTHFR gene and factor V Leiden), four patients were exposed to neosynephrine, two patients remained hypotensive perioperatively, and four delayed flap losses were attributed to pseudomonal infection. Five losses were technical or related to flap inexperience. Several representative case scenarios are illustrated. Conclusion: Careful review of free flap failures indicates that a thorough workup (particularly coagulation disorders), flap selection, surgeon to anesthesia communication, proper securing of the flap, and postoperative patient blood pressure and infection control have a greater part to play in this new era of anastomotic success.

Perioperative anaesthetic practice for head and neck free tissue transfer - a UK national survey

“…In a survey of 60 maxillofacial centres in the UK, 74% of centres conducted two to five cases a month; the study, however, did not specify whether the anaesthesia was conducted by the same or different anaesthetists . It is generally accepted that outcomes from complex specialist surgery are better when conducted in a specialist centre that is regularly performing that surgery and therefore will have the necessary operative experience and expertise as a multidisciplinary team …”

Free flap thrombosis in patients with hypercoagulability: A systematic review

“…Two studies were excluded because they included pedicled flaps [7,12]. One study was excluded because it explored the hemostasis profile in failed cases only [4]. Another study was excluded because some of the thrombophilia diagnoses were based only on thrombosis events related to the free flap procedure without a previous history of thromboembolic events or laboratory confirmation [13].…”

“…It is widely accepted that the anastomosis technique, the surgeon’s experience, and the type of free flap are the most influential factors in free tissue transfer procedures. Nevertheless, thrombophilia or hypercoagulability might pose a considerable problem [4]. In this review, we found six studies that were relevant for determining whether hypercoagulability is related to a higher incidence of free flap thrombosis.…”

“…Coagulopathy refers to a group of disorders considered to be a potential cause of flap loss that act synergistically with other well-identified factors 4 . Several reports have suggested that patients with a hypercoagulable state due to conditions such as malignancy, hereditary factors, and acquired thrombophilia might not be good candidates for free tissue transfer procedures 5 6 7 .…”

“…However, even with satisfactory anastomosis technique and adequate experience of the sur-geon, flap loss can still occur. Therefore, the failure of free flap procedures is deemed to be multifactorial [3,4]. Other factors associated with flap loss are coagulopathy, infection, vasopressors, hypotension, and the type of the flap [4].…”