Fingertip Blood Sensor Can Save Valuable Time in Trauma Assessment
October 9th, 2016
TUCSON, AZ – A tool now used to check for anemia in patients visiting physician offices could be employed in EDs to speed up medical decision-making for critically injured trauma patients, according to a new study.
For the research, published recently in the Journal of the American College of Surgeons, the use of the Spot check Pronto-7® Pulse CO-oximeter was evaluated in 525 critically injured patients.
Background in the study, led by trauma surgeons from the University of Arizona, suggests that the investigation was the largest ever for such a device.
The device is manufactured by Masimo of Irvine Park, CA, which did not provide any funding, devices or compensation for the study, according to study authors.
The current process is to send the sample to a clinical laboratory for analysis to get a reading on the hemoglobin count, which can take 10 minutes or longer, according to lead author Bellal Joseph, MD, FACS.
The spot check device, however, uses a fingertip sensor to provide a reading within 40 seconds to help determine the presence of internal bleeding.
“This device was initially intended for outpatient medical offices to obtain readings of people who were anemic, but the ability to get hemoglobin readings with a device that one places on the finger intrigued us,” Joseph said. “It can help make a medical decision very quickly about where this patient needs to go — to the operating room or intensive-care unit — without waiting for laboratory results. It gives us immediate information that we otherwise could not get.”
In the study, 450 (86%) of the 525 patients underwent the Spot check measurements successfully. Mean age of the patients was 41, 74% were male and the mean Injury Severity Score was 21. Hgb less than or equal to 8 mg/dL was detected in 38% of the patients at presentation.
With three Spot check measurements associated with an invasive blood draw, results showed a strong correlation between the two, according to the results. Mean invasive Hgb was 11.5 ± 4.36 g/dL, mean spot check Hgb was 11.1 ± 3.60 g/dL, and mean difference was 0.3 ± 1.3 g/dL.
Study authors note that spot check Hgb values had strong correlation with invasive Hgb measurements with 76% accuracy and 95.4% sensitivity.
In a few cases, sensor readings were disrupted for reasons such as nail polish on the patient’s fingernails or dust or soot on the patient’s fingers. There also were instances where the sensor did not fit the patient’s finger; although the device comes in three sizes, the research team only had access to one size.
Overall, the fingertip sensor showed some significant advantages over traditional intravenous blood draws, Joseph said.
“Sometimes patients are so severely injured when they come in, we have to place a special line in their neck or more central part of body to get blood,” he said. “It does not always have to be the extreme patient, but even the patient who seems fine may have internal bleeding.”
He said the device would be especially useful in the very young and very old, especially because of the difficulty in finding a good vein in elderly patients.
Next steps in evaluating trauma use of the device, according to Joseph, are:
- Implementing a protocol for nurses to use it,
- Extracting readings into the patient’s electronic medical records.
- Finding a way to use the device to continually monitor blood levels in patients with severe organ injuries at set time intervals
Joseph noted that Masimo will supply devices for a second study to learn more about how the monitor can be used in the trauma bay.