Why HF RFID

Environmental Factors

High Frequency (HF) RFID sponge management system incorporates the only technology that can reliably perform and deliver, within the hospital’s operating room environment, full count and detect capabilities to the hospital’s operating room team

 The technological capabilities & performance level between High Frequency (HF) RFID and Ultra High Frequency (UHF) RFID sponge management systems depend heavily on the environment in which communication is performed between each of these technologies’ respective readers and tags. In a hospital setting, and especially in the OR environment where there is substantial presence of environmental noise (in the form of liquids, chemicals, metals) and electromagnetic interference, a successful implementation of either HF or UHF, from both workflow and patient safety standpoints, depends on how reliable these technologies are when used in conjunction with the harsh OR environmental conditions. While HF technology has successfully been used in hospital ORs for years[1], mainly due to its capability to perform reliably under such harsh environmental noise and its immunity towards electromagnetic interference, UHF’s higher signal strength makes it more prone to electromagnetic interference[2] and is substantially limited in its performance in an OR environment full of liquids, chemicals, and metals. That is why UHF sponge management systems have not been deployed successfully in OR environments to date.

Detection Capabilities

Ultra High Frequency (UHF) RFID tags are incapable of being read and detected when inside, or behind, the patient’s tissue in the OR

 High Frequency (HF) RFID technology, because of its immunity to liquids, chemicals, metals, and electromagnetic interference, is the only technology with the ability to both count and detect item-level[3] surgical sponges consistently inside the OR patient and OR environment, thus able to substantially improve patient safety by eliminating RSI errors. Unlike the success of HF technology[4] in reliably detecting tagged sponges in the OR, Ultra High Frequency (UHF) RFID tags are incapable of being read and detected when inside, or behind, the patient’s tissue in the OR[5]. Thus, attempting to use the UHF RFID technology for detection purposes in the OR is highly limited to detecting sponges that (1) are only outside the patient’s body and (2) through algorithm manipulation, are only sponges that were initially counted in (i.e., if a new UHF sponge is inserted during the operation, and the OR staff was unable to scan in the new UHF sponge, as often occurs due to time and/or human workflow error, there will be no way of detecting that new UHF sponge at the reconciliation/closing stage of the surgery). 

Reading Capabilities

Only a High Frequency (HF) RFID sponge management system can reliably eliminate false positive and false negative readings in your operating room

The primary benefit of using a High Frequency (HF) RFID sponge management system for counting and tracking item-level RSIs is its superior accuracy (energy emitted does not travel to increased distance) of reading[6] (tagged sponges are not limited by liquids, chemicals, and metals), and, as a result, eliminating false positives and false negatives in the OR[7]. The limitations of Ultra High Frequency (UHF), mainly that (1) its emitting energy travels to increased distance, thus not preventing readings of unwanted UHF sponges in the OR and (2) the UHF communication being absorbed by liquids, chemicals, human tissues and bones (as often found under the operated patient’s tissue[8]), and being bounced off metal tools and metal devices in the OR, increase the chances of false positive and false negative readings for your team in the OR. 

Specific Absorption Rate (SAR)

High Frequency (HF) RFID technology used in a sponge management system imposes no risk with regards to SAR

 

The electromagnetic field (EMF) exposure from an Ultra High Frequency (UHF) gun (reader) emitting power at the level of 1 W, or above, may cause SAR values to exceed general public limits, thus potentially categorizing the OR staff holding the UHF reader, as well as other bystander OR team members, or the scanned patient in the OR, as individuals at particular risk[9]. Specifically, any users of active implantable medical device (AIMD) and pregnant women who are in close proximity to a Ultra High Frequency (UHF) gun reader emitting power at the level of 1 W should be treated as individuals at particular risk.

References 

[1] https://www.packagingdigest.com/rfid/rfid-hf-versus-uhf-technologies-part-two

[2] https://jamanetwork.com/journals/jama/fullarticle/182113

[3] https://www.packagingdigest.com/rfid/comparing-hf-and-uhf-rfid-technologies

[4] https://clpmag.com/miscellaneous/study-finds-uhf-from-rfid-technologies-interferes-with-medical-devices/

[5] https://www.sciencedirect.com/science/article/pii/S1631070511001563/pdf?md5=4c112ad0057bd805b4c23417ebdafd44&pid=1-s2.0-S1631070511001563-main.pdf&_valck=1 (Paragraph 4.3)

[6] https://www.packagingdigest.com/rfid/rfid-hf-versus-uhf-technologies-part-two

[7] http://www.ncbi.nlm.nih.gov/pubmed/28230583

[8] https://www.sciencedirect.com/science/article/pii/S1631070511001563/pdf?md5=4c112ad0057bd805b4c23417ebdafd44&pid=1-s2.0-S1631070511001563-main.pdf&_valck=1 (Paragraph 4.3)

[9] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6982864/