The Clotting Effects of Pentastarch and Normal Saline in Obstetric Patients
Status:
Completed
Trial end date:
2008-02-01
Target enrollment:
Participant gender:
Summary
Pregnant women are more likely to form clots than non-pregnant women as pregnancy increases
the clotting factors present in the blood. This helps to prevent excess bleeding (hemorrhage)
at the time of delivery. Hemorrhage occurs in 5-15% of pregnancies throughout the world, even
when delivery is by cesarean section. When hemorrhage occurs the anesthesiologist will
normally administer fluids into the woman's vein (intravenously) rapidly to replace the blood
that the woman has lost. Two types of fluids are commonly used. One is a salt water solution
(saline) and the other is a starch water solution (pentastarch). Use of either or both of
these solutions is common during hemorrhage.
These same solutions (salt water solution and starch solution) are used at BC Women's
Hospital during spinal anesthesia to prevent and treat low blood pressure (a common side
effect of spinal anesthesia). This is standard practice whether you are in this study or not.
You may also be given, depending on the anesthesiologist's preference, a drug (vasopressor)
that causes the blood vessels to become narrow (constrict) to prevent or treat the low blood
pressure. Whether you agree to be part of the study or not, your anesthesiologist will be
watching your blood pressure closely throughout your operation and if your blood pressure
becomes low he/she will treat it as is normally done.
Low blood pressure will also occur during hemorrhage. It is therefore important that we
determine whether the starch solution, which is more effective than the salt solution in
preventing low blood pressure during spinal anesthesia, does or does not affect clotting.
Research in non-pregnant adults (male and female) has found that laboratory tests of blood
clotting change with these solutions. For saline the evidence in some studies suggests that
the blood may clot better than normal while other studies suggest the opposite (does not clot
as well). In pregnant and non-pregnant adults the blood does not clot as well with certain
starch solutions. The starch solution used at BC Women's Hospital is called pentastarch and
no research has looked at its effect on clotting in pregnant women. In non-pregnant adults
pentastarch has less effect on clotting than other starch solutions.
The purpose of the study is to see how pentastarch (starch solution) and normal saline (water
with salt in it) given at the time of spinal anesthesia for elective cesarean section affect
the ability of pregnant woman's blood to clot.
Phase:
N/A
Details
Lead Sponsor:
University of British Columbia
Collaborator:
Children's & Women's Health Centre of British Columbia