Usefulness of Coagulation Studies and Blood Banking in Patients with Symptomatic Placenta Previa

ABSTRACT

We conducted this study to ascertain the usefulness of coagulation studies and blood bank utilization in the patient with symptomatic placenta previa. During a 2-year interval, 97 patients with uterine bleeding due to placenta previa diagnosed ≥ 24 weeks' gestation were evaluated. The following studies were routinely obtained: complete blood count including platelet count, fibrinogen, prothrombin time, and a Kleihauer-Betke test. A type and cross-match was sent to the blood bank, and blood availability was maintained for all patients throughout the course of hospitalization. For 92 of 97 patients the laboratory values and need for immediate blood availability were analyzed. No abnormal prothrombin times or Kleihauer-Betke tests were found. There was one low fibrinogen value in a patient with a normal complete blood count. The initial hematocrits ranged from 16.5 to 40.0%, and the initial hemoglobins ranged from 5.5 to 14.1 mg/dL. Five patients had platelet counts of ≤ 150 k/mm³ (range 75 to 149 k/mm³). Fourteen patients (14.6%) required transfusion, two received their transfusion antepartum and 12 received perioperative transfusion with a cesarean delivery. During this time period, only two patients required emergent delivery within 1 hr of presentation to the hospital. One patient had delayed seeking medical attention for more than 3 hr prior to admission despite significant hemorrhage. Coagulation studies and Kleihauer-Betke tests have limited utility in the symptomatic patient with uterine bleeding from placenta previa. Continuous availability of cross-matched blood in the antepartum period appears unnecessary as no patients in this investigation were transfused emergently.

Keywords

Placenta previa - antepartum vaginal bleeding - coagulation studies - Kleihauer-Betke