title: Prophylaxis of thromboembolism in bariatric surgery with parnaparin.
abstract: BACKGROUND
  There are limited data on appropriate dosing of low-molecular-weight heparins (LMWHs) for venous thromboembolism (VTE) prophylaxis in bariatric surgery. The primary objective of this preliminary study was to evaluate the preoperative effects of increasing doses of the LMWH parnaparin on coagulation in severely obese patients undergoing bariatric surgery.
  
  
  METHODS
  Severely obese patients (BMI > 50 kg/m(2)) were administered three increasing single doses of parnaparin (3200, 4250, and 6400 IU) on the three consecutive days leading up to biliointestinal bypass surgery. Activated partial thromboplastin time (APTT), anti-factor IIa and anti-factor Xa levels were measured 1 h before and 4 h after dosing. The highest dose (6400 IU/day) was continued from the day of surgery until day 30 (recovery period). Intermittent pneumatic compression and stockings were applied during surgery and the recovery period, respectively. Lower limb echoDoppler and phleboscintigraphy, and pulmonary scintigraphy were used for VTE detection.
  
  
  RESULTS
  Ten patients (mean BMI 52.4 kg/m(2)) were recruited into this study. During the preoperative dosing phase, parnaparin dose-dependently prolonged APTT, with the 6400 IU dose significantly prolonging APTT versus the lower doses. Meanwhile, anti-factor Xa and anti-factor IIa activity was increased by the 4250 and 6400 IU doses. After surgery, one patient with heparin resistance experienced pulmonary embolization. No bleeding complications were observed.
  
  
  CONCLUSIONS
  The dose-response data reported in this preliminary study suggest that parnaparin doses of 4250 and 6400 IU may provide effective prophylaxis for VTE in patients undergoing bariatric surgery. However, given the small number of patients, larger, well-controlled trials are required to confirm these findings.
authors.affiliation: Dipartimento di Chirurgia Generale, Geriatrica, Oncologica e Tecnologie Avanzate, Università degli Studi Federico II, Via S. Pansini 5, I-80132 Naples, Italy. forestie@unima.it
authors.forename: Pietro
authors.initials: P
authors.lastname: Forestieri
authors.forename: Gennaro
authors.initials: G
authors.lastname: Quarto
authors.forename: Maurizio
authors.initials: M
authors.lastname: De Caterina
authors.forename: Alberto
authors.initials: A
authors.lastname: Cuocolo
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Pilone
authors.forename: Antonio
authors.initials: A
authors.lastname: Formato
authors.forename: Aldo
authors.initials: A
authors.lastname: Ruocco
authors.forename: Patrizio
authors.initials: P
authors.lastname: Ferrari
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage*; D050110:Bariatric Surgery; D001780:Blood Coagulation Tests; D015992:Body Mass Index; D003131:Combined Modality Therapy; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D006495:Heparin, Low-Molecular-Weight / Q000008:administration & dosage*; D006801:Humans; D048228:Intermittent Pneumatic Compression Devices; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology / Q000517:prevention & control*; D011292:Premedication; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging / Q000209:etiology; D011877:Radionuclide Imaging; D053828:Stockings, Compression; D054556:Venous Thromboembolism / Q000209:etiology / Q000517:prevention & control*
chemical_list: D000925:Anticoagulants; D006495:Heparin, Low-Molecular-Weight; C080945:parnaparin