title: Protein C deficiency in microvascular head and neck reconstruction.
abstract: OBJECTIVE
  To determine the incidence of perioperative protein C deficiency in patients undergoing free flap reconstruction of cancer-related defects in the head and neck.
  
  
  METHODS
  Prospective case series.
  
  
  METHODS
  Ten patients underwent microvascular reconstruction after surgical therapy of carcinomas of the oral cavity or oropharynx. Coagulation studies were determined in all patients 72 hours after surgery.
  
  
  METHODS
  Academic tertiary care medical center
  
  
  RESULTS
  Protein C deficiency was detected in 70% of patients. One free flap failure was attributed to protein C deficiency.
  
  
  CONCLUSIONS
  Vitamin K-dependent clotting factors are frequently deficient during the postoperative period after major head and neck surgery, which may result in a state of hypercoagulability. Protein C deficiency should be considered as a possible cause of free flap thrombosis in patients who undergo microvascular head and neck reconstruction.
authors.affiliation: Department of Surgery, University of California Los Angeles School of Medicine 90095, USA.
authors.forename: C
authors.initials: C
authors.lastname: Ayala
authors.forename: K E
authors.initials: KE
authors.lastname: Blackwell
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000150:complications / Q000601:surgery*; D005260:Female; D006258:Head and Neck Neoplasms / Q000150:complications / Q000601:surgery*; D006801:Humans; D008297:Male; D008866:Microsurgery / Q000379:methods; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D013517:Otorhinolaryngologic Surgical Procedures / Q000379:methods*; D011183:Postoperative Complications / Q000209:etiology; D011446:Prospective Studies; D020151:Protein C Deficiency / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology*; D013524:Surgical Flaps / Q000098:blood supply / Q000473:pathology; D013923:Thromboembolism / Q000209:etiology / Q000473:pathology; D014813:Vitamin K Deficiency / Q000150:complications