Clinical Investigations

Prolonged Prophylaxis with Unfractioned Heparin Is Effective to Reduce Delayed Deep Vein Thrombosis in Total Hip Replacement
Daniela Manganelli^a, Marcello Pazzagli^a, David Mazzantini^a, Giovanni Punzi^b, Mario Manca^b, Claudio Vignali^c, Alessandro Palla^c, Riccardo Troiani^d, Giuseppe Rossi^a, Antonio Palla<sup>a

a</sup> Respiratory Pathophysiology and CNR Institute of Clinical Physiology,
^b First and Second Orthopedic Clinics,
^c Department of Radiology,
^d Third Department of Anesthesiology, University of Pisa, Italy

Address of Corresponding Author

Respiration 1998;65:369-374 (DOI: 10.1159/000029297)

  Key Words

• Deep vein thrombosis
• Pulmonary embolism
• Hip replacement
• Heparin prophylaxis

  Abstract

The aim of this study was to assess the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) until 45 days after elective total hip replacement (THR) and the efficacy of prolonged unfractioned heparin (UH) prophylaxis up to postoperative day 30. To this end 79 of 96 patients admitted consecutively to the University Hospital of Pisa for THR were randomly assigned to short- or long-term UH prophylaxis. Sixty-one patients completed the study: 28 of them received short-term prophylaxis (subcutaneous UH 15,000 IU/24 h for 15 days) and 33 prolonged prophylaxis (subcutaneous UH 15,000 IU/24 h for 30 days). Lower limb phlebography was performed in all patients on day 45 after THR. DVT was demonstrated in 10 (16.3%) cases after hospital discharge. Among them, 2 patients also had symptomatic PE. The incidence of DVT was 21.4% in short- and 12.1% in long-term UH-treated patients. The incidence of only proximal DVT was 17.8% in short- and 3.0% in long-term UH-treated patients; although the difference was only close to significance (p = 0.085), the relative risk of developing proximal DVT was about six times greater in the former group of patients. We concluded that the risk for thromboembolism persists at least until 45 days after surgery in patients subjected to THR. Prophylaxis with UH given up to postoperative day 30 appears more effective and safer in reducing the delayed thromboembolic risk compared to prophylaxis with UH given up to discharge only.

  Author Contacts

Antonio Palla, MD, FCCP
Fisiopatologia Respiratoria
Ospedale Cisanello, via Paradisa 2
I-56100 Pisa (Italy)
Tel. +39 50 596838, Fax +39 50 580126

  Article Information

This work was supported in part by funds from the National Research Council, Cardiorespiratory Group, and the Italian Ministry of University and Scientific and Technologic Research.

Received: Received: November 6, 1997
Accepted after revision: March 3, 1998
Number of Print Pages : 6
Number of Figures : 0, Number of Tables : 4, Number of References : 32