Estimating Blood Loss Using TritonTM in Vaginal Deliveries: A Validation Trial

Postpartum hemorrhage (PPH) is the leading cause of maternal mortality in low-income countries and the primary cause of nearly one quarter of all maternal deaths globally (1). An estimated blood loss (EBL) in excess of 500 mL following a vaginal birth has often been used for the definition of PPH, but the average volume of blood lost at delivery can approach these amounts when actually measured rather than estimated (2). More than half of all maternal deaths occur within 24 hours of delivery, most commonly from excessive bleeding (3). Worldwide, 140,000 women succumb to postpartum hemorrhage each year. The most common antecedents to postpartum hemorrhage are uterine atony, placental disorders, and trauma during delivery. Improving maternal health worldwide is one of the WHO's 8 Millennium Developmental Goals. The prevention and treatment of PPH is an essential step towards the achievement of that goal (4).

Estimates of blood loss at delivery are notoriously inaccurate, with under-estimation more common than over-estimation (5). Traditionally, the clinicians performing the vaginal delivery would estimate the blood loss by visually assessing the blood collected in the delivery drape drain and counting the number of lap sponges used thru out the delivery. Current detection and management of hemorrhage is heavily based on clinical judgment, which often leads to delay in recognition and intervention. Often, interventions such as fluid resuscitation and blood transfusion are not initiated until significant hemorrhage has already taken place. The traditional method for estimating blood loss is based on the clinician and nursing staff's subjective assessment that is severely limited by human error and the presence of large volumes of amniotic fluid (6).

Early detection and treatment of this potentially life-threatening obstetric complication is of utmost importance in the field of obstetrics. Simulations and didactic training have been shown to improve visual estimations, but there are still poor associations between experience level and accuracy, and a significant decay in blood loss estimation skills over time (7).

The Triton L&D system (Gauss Surgical, Inc., Menlo Park, CA) is an FDA-cleared mobile application on a tablet computer (iPad) that facilitates quantification of blood loss (QBL) by providing an easy to use process and user interface. Dry weights of all potential blood containing substrates are built-in to the device allowing batch weighing with automatic subtraction of dry weights. There is also a V-drape simulator accounting for collected fluids with automatic subtraction of a measured amount of amniotic fluid.

QBL is not regularly used at UTMB. Although widely recommended, little data is available to support its use in the obstetrical population. We believe that gathering further evidence regarding its value is appropriate.