title: Preoperative Platelet Count Predicts Lower Extremity Free Flap Thrombosis: A Multi-Institutional Experience.
abstract: BACKGROUND
  Thrombocytosis in patients undergoing lower extremity free tissue transfer may be associated with increased risk of microvascular complications. This study assessed whether preoperative platelet counts predict lower extremity free flap thrombosis.
  
  
  METHODS
  All patients undergoing lower extremity free tissue transfer at Duke University from 1997 to 2013 and at the University of Pennsylvania from 2002 to 2013 were retrospectively identified. Logistic regression was used to assess whether preoperative platelet counts independently predict flap thrombosis, controlling for baseline and operative factors.
  
  
  RESULTS
  A total of 565 patients underwent lower extremity free tissue transfer, with an overall flap thrombosis rate of 16 percent (n = 91). Elevated preoperative platelet counts were independently associated with both intraoperative thrombosis (500 ± 120 versus 316 ± 144 × 10/liter; p < 0.001) and postoperative thrombosis (410 ± 183 versus 320 ± 143 × 10/liter; p = 0.040) in 215 patients who sustained acute lower extremity trauma within 30 days before reconstruction. In acute trauma patients, preoperative platelet counts predicted a four-fold increased risk of intraoperative thrombosis (cutoff value, 403 × 10/liter; OR, 4.08; p < 0.001) and a two-fold increased risk of postoperative thrombosis (cutoff value, 361 × 10/liter; OR, 2.16; p = 0.005). In patients who did not sustain acute trauma, preoperative platelet counts predicted a four-fold increased risk of intraoperative thrombosis (cutoff value, 352 × 10/liter; OR, 3.82; p = 0.002).
  
  
  CONCLUSIONS
  Acute trauma patients with elevated preoperative platelet counts are at increased risk for lower extremity free flap complications. Prospective evaluation is warranted for guiding risk stratification and targeted treatment strategies.
  
  
  METHODS
  Risk, III.
authors.affiliation: Durham, N.C.; and Philadelphia, Pa.|From the Division of Plastic and Reconstructive Surgery, Duke University Health System; and the Division of Plastic Surgery and the Department of Orthopaedic Surgery, University of Pennsylvania Health System.
authors.forename: Eugenia H
authors.initials: EH
authors.lastname: Cho
authors.affiliation: Durham, N.C.; and Philadelphia, Pa.|From the Division of Plastic and Reconstructive Surgery, Duke University Health System; and the Division of Plastic Surgery and the Department of Orthopaedic Surgery, University of Pennsylvania Health System.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Bauder
authors.affiliation: Durham, N.C.; and Philadelphia, Pa.|From the Division of Plastic and Reconstructive Surgery, Duke University Health System; and the Division of Plastic Surgery and the Department of Orthopaedic Surgery, University of Pennsylvania Health System.
authors.forename: Sierra
authors.initials: S
authors.lastname: Centkowski
authors.affiliation: Durham, N.C.; and Philadelphia, Pa.|From the Division of Plastic and Reconstructive Surgery, Duke University Health System; and the Division of Plastic Surgery and the Department of Orthopaedic Surgery, University of Pennsylvania Health System.
authors.forename: Ronnie L
authors.initials: RL
authors.lastname: Shammas
authors.affiliation: Durham, N.C.; and Philadelphia, Pa.|From the Division of Plastic and Reconstructive Surgery, Duke University Health System; and the Division of Plastic Surgery and the Department of Orthopaedic Surgery, University of Pennsylvania Health System.
authors.forename: Lily
authors.initials: L
authors.lastname: Mundy
authors.affiliation: Durham, N.C.; and Philadelphia, Pa.|From the Division of Plastic and Reconstructive Surgery, Duke University Health System; and the Division of Plastic Surgery and the Department of Orthopaedic Surgery, University of Pennsylvania Health System.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Kovach
authors.affiliation: Durham, N.C.; and Philadelphia, Pa.|From the Division of Plastic and Reconstructive Surgery, Duke University Health System; and the Division of Plastic Surgery and the Department of Orthopaedic Surgery, University of Pennsylvania Health System.
authors.forename: L Scott
authors.initials: LS
authors.lastname: Levin
authors.affiliation: Durham, N.C.; and Philadelphia, Pa.|From the Division of Plastic and Reconstructive Surgery, Duke University Health System; and the Division of Plastic Surgery and the Department of Orthopaedic Surgery, University of Pennsylvania Health System.
authors.forename: Scott T
authors.initials: ST
authors.lastname: Hollenbeck
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D058752:Free Tissue Flaps / Q000098:blood supply* / Q000637:transplantation; D006801:Humans; D016015:Logistic Models; D035002:Lower Extremity / Q000098:blood supply / Q000293:injuries / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology*; D057234:Preoperative Period; D019651:Plastic Surgery Procedures; D012189:Retrospective Studies; D012307:Risk Factors; D013927:Thrombosis / Q000175:diagnosis / Q000209:etiology*; D016896:Treatment Outcome