title: The increased risk of adverse outcomes in bilateral deep inferior epigastric artery perforator flap breast reconstruction compared to unilateral reconstruction: a systematic review and meta-analysis.
abstract: BACKGROUND
  The rate of bilateral mastectomy and bilateral breast reconstruction is increasing. The DIEP flap is an ideal method of breast reconstruction. The difference in risk of adverse outcomes between unilateral and bilateral DIEP flap breast reconstruction is unclear. The aim of this review is to investigate this relationship.
  
  
  METHODS
  Authors searched Ovid EMBASE and MEDLINE from database inception to March 2012, for reports of DIEP flap breast reconstruction studies. After screening, data were extracted on flap-related, donor-site and systemic adverse events. Descriptive statistics were generated for all pooled data. We performed meta-analysis of direct comparisons to generate relative risk (RR) ratios with 95% confidence intervals (CI) using a random-effects model.
  
  
  RESULTS
  Overall, 17 case-series of 2398 women were included. Compared with unilateral DIEP flap breast reconstruction, bilateral reconstruction was associated with a significantly higher risk of total flap failure (RR 3.31 [95% CI 1.50-7.28]; p = 0.003) and breast seroma (RR 7.15 [95% CI 1.21-42.36]; p = 0.03). Differences between other outcomes were non-significant, although descriptive analysis appeared to favour unilateral reconstruction.
  
  
  CONCLUSIONS
  The current literature related to DIEP flap breast reconstruction appears to be of low quality. However, this is the first systematic review confirming that bilateral DIEP flap breast reconstruction is associated with a significantly higher risk of total flap failure compared to unilateral DIEP flap breast reconstruction. This review will allow clinicians to better inform patients of the risks of adverse outcomes in DIEP flap breast reconstruction. It also highlights the need for higher quality research in this area.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Norfolk and Norwich University Hospital, NHS Foundation Trust, Norwich, UK; Faculty of Medicine and Health Science, Norwich Medical School, University of East Anglia, Norwich, UK.
authors.forename: Justin C R
authors.initials: JC
authors.lastname: Wormald
authors.affiliation: Department of Plastic and Reconstructive Surgery, Norfolk and Norwich University Hospital, NHS Foundation Trust, Norwich, UK.
authors.forename: Ryckie G
authors.initials: RG
authors.lastname: Wade
authors.affiliation: Department of Plastic and Reconstructive Surgery, Norfolk and Norwich University Hospital, NHS Foundation Trust, Norwich, UK; Faculty of Medicine and Health Science, Norwich Medical School, University of East Anglia, Norwich, UK. Electronic address: andrea.figus@nnuh.nhs.uk.
authors.forename: Andrea
authors.initials: A
authors.lastname: Figus
mesh_terms: D019074:Epigastric Arteries; D005260:Female; D006085:Graft Survival; D006801:Humans; D016462:Mammaplasty / Q000009:adverse effects* / Q000379:methods*; D008408:Mastectomy; D061525:Perforator Flap / Q000009:adverse effects*; D049291:Seroma / Q000209:etiology
keywords: Adverse outcomes; Bilateral; Breast; Complications; DIEAP; DIEP; Deep inferior epigastric artery perforator flap; Failure; Free flap; Meta-analysis; Microvascular; Reconstruction; Review; Unilateral