Bleeding after intravascular transfusion: experimental and clinical observations.

Abstract

Characteristics of postpuncture bleeding of umbilical vessels were evaluated with an in vitro cord perfusion model and in vivo by ultrasonographic observation of bleeding duration after intravascular transfusion. Ultrasonographic determination of blood loss in vitro was very sensitive (0.01 ml/sec). In vitro blood loss varied directly with perfusion rate, but there were wide variations between cord specimens. Observed clinical bleeding occurred in 43% of cases; the duration of bleeding varied by vessel punctured, needle size, and fetal platelet count. The combined in vitro and clinical data help define the range of duration of bleeding and the probable volume of loss.