Prevention of Pulmonary Embolism in General Surgery Patients

Case Presentation : A 29-year-old woman presented to the emergency department with complaints of pleuritic chest pain, fever, and left ankle swelling and tenderness. Cardiac examination was normal except for tachycardia. A chest computed tomography scan with contrast demonstrated extensive bilateral pulmonary emboli. Thirteen days previously, an intoxicated driver with multiple prior convictions for driving under the influence of alcohol crashed head-on into her car at a high speed. She was 8 months’ pregnant and suffered the loss of the child. She spent 7 days in the hospital and underwent cesarean section, exploratory laparotomy, and splenectomy. No preoperative pharmacological prophylaxis against venous thromboembolism (VTE) was administered.VTE, which includes deep vein thrombosis (DVT) and pulmonary embolism (PE), is an important and common complication of general surgery.A new era in the postoperative management of surgical patients began in 1975 when the effectiveness of low-dose heparin in preventing postoperative DVT and PE was established by the pivotal International Multicenter Trial.1 The dose was 5000 U subcutaneously every 8 hours, with the first injection administered 2 hours before the skin incision. Compared with control, the incidence of DVT in patients receiving heparin decreased from 24.6% to 7.7%. Similarly, the incidence of autopsy-proven PE was reduced 8-fold. The results of this trial introduced and validated the concept of using low-dose heparin to prevent postoperative VTE. This trial revolutionized surgical practice. By 1994, 90% of North American general surgeons reported the routine use of thromboprophylaxis.2Most postoperative DVT originates in the deep calf veins, primarily within the valve cusps. Most thrombi remain confined to the calf. Propagation into the proximal veins increases the risk of PE. Symptoms and signs of postoperative VTE such as mild hypoxia or low-grade fever are frequently nonspecific. Moreover, clinical manifestations of postoperative VTE may not occur until …