The previous post described the Triton System™, an iPad application, combined with a modest amount of hardware (a footswitch) that scans surgical sponges, uploads the data to a cloud server, and estimates hemoglobin mass. In that study, reconstituted blood was used to measure the system’s accuracy. Dr. Allen A. Holmes, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, and colleagues assessed both the performance and accuracy of the Triton during surgical cases where it was expected that many laparotomy sponges would be used. Their findings are published in this month’s edition of Anesthesia & Analgesia in the article titled “Clinical Evaluation of a Novel System for Monitoring Surgical Hemoglobin Loss.”
Forty-six patients undergoing surgery with anticipated significant blood loss were included in this multicenter study. Hemoglobin mass measured using the Triton system correlated highly with hemoglobin rinsed from the sponges. For 12 procedures, measures on individual sponges were available: there was a modest overestimation of hemoglobin loss with the Triton systemTM. Measurement bias was equivalent to about 0.16 unit-equivalents of a 450-mL unit of whole blood. Accuracy was higher with the Triton systemTM than with gravimetric measurement of blood loss.
The gravimetric method to determine blood loss is more accurate than visual estimation. However, and counterintuitively, gravimetric methods have significantly decreased in popularity over the years and visual determination of blood loss is still widely used. This Triton technique appears to allow accurate and rapid measurement of blood loss on sponges, and is more accurate than weighing sponges.
It is worth asking whether outcome will be improved by use of this technology? Specifically, will less blood be transfused? Will the savings accrued from using less blood products pay for the cost of this device? Will patient outcomes improve? Maybe. Echoing the Faber College motto, “Knowledge is Good,” improving the accuracy of blood loss estimation can only improve the ability to make informed clinical decisions about perioperative transfusion.