In the Field: Masimo Rad-57 Handheld Oximeter

   In cooperation with the International Association of Fire Chiefs and the National Fire Protection Association, Masimo Corporation has funded a nationwide series of educational events regarding NFPA 1584: Standards on the Rehabilitation Process for Members During Emergency Operations and Training Exercise. A key element of this training is the importance of recognizing the danger carbon monoxide (CO) poses on the fireground, and the use of Masimo's Rad-57 handheld oximeter in the rehab sector.

   Prior to the Rad-57 introduction, CO poisoning on the fireground could only be identified through signs and symptoms after exposure levels had reached dangerous levels. CO levels could only be measured from blood drawn by blood gas analysis in the hospital. This process took precious time and was limited to clinical settings. The Rad-57 brings CO measurement to fire and training grounds in a painless, non-invasive device that delivers readings in seconds.

   A sensor clips over the patient's finger like many standard pulse oximetry units. Proper sensor placement is especially important to ensure accurate measurements. The LED screen can be cycled to show the patient's oxygen saturation (SpO2), pulse rate and carboxyhemoglobin saturation (SpCO). A perfusion index monitor ensures the sensor is getting adequate blood flow in order to measure accurately. Optional software upgrades allow the Rad-57 to measure methemoglobin (SpMet), total hemoglobin (SpHb), oxygen content (SpOC) and the Pleth Variability Index (PVI).

   Audible and visual alarms for readings that are out of "normal" range are pre-programmed at the factory, but can be reset by the user if desired. SpO2 readings below 92%, SpCO readings over 10% and inadequate perfusion are the baseline settings.

   Riverside Fire Authority (RFA), a fire-based ALS agency serving 180 square miles in and around Centralia, WA, purchased a Rad-57 unit while in the process of enhancing its firefighter rehabilitation program. Two questions arose as a result of this purchase. The first involved the rationale and science driving the factory alarm settings. After research and consultation with Riverside's medical program director, the alarms were left at the factory defaults.

   The second question was whether county EMS protocols would need to be revised to allow BLS-level personnel to use the device. After discussing this with authorities and neighboring jurisdictions also using the device, officials decided the device is a medical monitoring tool and not a means of patient care. The tool may lead its operator to request patient care for the firefighter being monitored, which, according to RFA rehab procedures, will be provided by a paramedic operating under county protocols. Therefore, no special permission was needed for Riverside BLS providers to use the CO monitor in the course of rehab medical monitoring.

   The first in-the-field test of the Rad-57 occurred at a training burn. A large convalescent center had been damaged beyond repair by flooding. After many months of valuable training in the building, it was used for an all-day live-fire training event. Baseline measurements were taken on all firefighters who would be working in combat roles. The only measurement recorded over 0% was on a firefighter who, while a non-smoker, was in the company of smokers immediately prior to reporting to the training event and measured 3% SpCO. Interestingly enough, later measurements taken on the same firefighter after working inside on SCBA showed consistent 0% readings.

   Three EMTs and one first responder took turns using the Rad-57 to test firefighters throughout the day. With the device's automation and presets, training took less than a minute.

   Firefighters were interested in their readings and universally positive about the safety aspects of being able to monitor CO at a fire. RFA's rehab procedures call for periodic testing of everyone on the fireground, including engineers and command positions. The only elevated CO level found was a 4% reading on one engineer after several hours of operating the pump on the primary attack engine.

   Prior to RFA's first field usage of the Rad-57, the device was used during a practice burn in a neighboring county. The simplicity of the unit and the short learning curve were also noted there. The only concern was one poor reading on a female firefighter's small hand. The operator did not have a pediatric-sized probe to try instead.

   Elevated CO levels were detected in two ignition officers who had spent considerable time in the building off their SCBA air between the end of a suppression effort and the lighting of the next training fire. This was seen as validation of the device's usefulness as a firefighter safety tool. The department is modifying its rehab procedures to make using the Rad-57 standard practice at any significant emergency or training event.

   The Masimo Rad-57 offers departments another firefighter safety enhancement tool. Many firefighter line-of-duty deaths are cardiac-related and medical evidence shows the damage elevated CO causes to cardiac muscle. RFA paid $4,400 for its unit, so acquisition may be out of reach for smaller agencies. However, for agencies that can afford the unit, this simple-to-use device offers every incident commander the opportunity to save firefighters' lives by preventing CO from reaching dangerous levels.

   For more, see www.masimo.com/rad-57/index.htm.

Ed Mund began his fire and EMS career in 1989. He currently serves with Riverside Fire Authority, a fire-based ALS agency in Centralia, WA. His writing and photos have been published in several industry publications. Contact him at ems@emedstrat.com.