Intraluminal pressure readings during the establishment of a positive 'tamponade test' in the management of postpartum haemorrhage.
OBJECTIVE
To investigate the proposed mechanism by which intrauterine balloons achieve their tamponade effect of creating an 'intrauterine pressure that is greater than the systemic arterial pressure'.


METHODS
To determine the intraluminal pressures within a Bakri balloon during the establishment of a positive 'tamponade test' in the management of postpartum haemorrhage. To correlate these intraluminal pressures with contemporaneous readings of blood pressure recordings as documented from the operating theatre anaesthetic charts.


METHODS
An obstetric unit (approximately 2400 births) in Wollongong, New South Wales, Australia.


METHODS
Two women in whom first-line uterotonics were unsuccessful and who required a Bakri balloon to control postpartum haemorrhage secondary to an atonic uterus.


METHODS
A DigiMano (Netech Corporation, Farmingdale, NY, USA) pressure recorder was attached via a three-way tap to a Bakri balloon. Anaesthetic charts of the two cases were reviewed retrospectively.


METHODS
Intraluminal pressure readings were recorded after each 50-ml aliquot of normal saline had been insufflated into the balloon whilst the next aliquot was being prepared.


RESULTS
There is a curvilinear relationship between the intraluminal pressure and the balloon volume. The pressure does not exceed the systolic blood pressure of the patient at the time of establishment of a positive tamponade test.


CONCLUSIONS
The intraluminal pressure within the tamponade balloon does not exceed the systolic blood pressure of the patient when a positive tamponade test is established.
Georgiou
C
C
Illawarra Health and Medical Research Institute/Graduate School of Medicine, University of Wollongong, and Wollongong Hospital, Department of Obstetrics and Gynaecology, Illawarra, NSW, Australia. georgiou@uow.edu.au
D000328:Adult; D021721:Balloon Occlusion; D001794:Blood Pressure / Q000502:physiology; D002404:Catheterization / Q000379:methods*; D020878:Device Removal; D005260:Female; D006489:Hemostatic Techniques; D006801:Humans; D006473:Postpartum Hemorrhage / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D011247:Pregnancy; D011312:Pressure; D014593:Uterine Inertia / Q000503:physiopathology