Aims: Multiple techniques exist to monitor free flap viability postoperatively, varying with practical
and personal preference, yet the limitations of each technique remain unquantified. This
systematic review aims to identify the most commonly reported limitations of these techniques in
clinical practice.
Methods: A systematic review was conducted according to PRISMA guidelines using MEDLINE,
EMBASE and Web of Science with search criteria for postoperative free flap monitoring
techniques. Search results were independently screened using defined criteria by two authors
and a senior clinician. Limitations of the techniques found in the discussion section of eligible
papers were recorded and categorised using thematic analysis.
Results: A total of 4699 records were identified. 2210 articles met the eligibility criteria and were
subsequently reviewed, with 195 papers included in the final analysis. The most frequently
reported limitations of clinical monitoring were: interpretation requiring expertise (25% of related
papers), unsuitability for buried flaps (21%), and lack of quantitative/objective values (19%). For
non-invasive technologies: lack of quantitative/objective values (21%), cost (16%) and
interpretation requiring expertise (13%). For invasive technologies: application requiring expertise
(25%), equipment design and malfunction (13%) and cost (13%).
Conclusions: This is the first systematic review to quantify the limitations of different flap
monitoring techniques as reported in the literature. This information may enhance the choice in
monitoring strategy for a reconstructive service and inform the development and refinement of
new flap monitoring technologies.