Carbon Monoxide and the Rad-57

1
Carbon Monoxide and the Rad-57

• Jeremy T. Cushman, MD, MS, EMT-P
• Monroe County EMS Medical Director
• Division of Prehospital Medicine, URMC

2
CO-Related Deaths in 2000
3
What is it?

• Carbon Monoxide (CO) is a
• colorless and odorless gas.
• It is poisonous to people and animals,
• because it displaces oxygen in the blood.
• It is produced by the incomplete burning of
  solid, liquid, and gaseous fuels.
• Appliances fueled with natural gas, liquefied
  petroleum (LP gas), oil, kerosene, coal, or wood
  may produce CO. Burning charcoal and running
  combustion engines (cars, motorcycles,
  generators, etc) produce CO.

4
How much causes symptoms?
5
Normal Hemoglobin

• Normal oxygenation of the tetrameric (ie. 4
  subunits) hemoglobin molecule.
• As it goes from (deoxy)hemoglobin to
  oxyhemoglobin the color changes from blue, as in
  venous blood, then to pink, as in arterial blood.

6
Carboxyhemoglobin

• Here carbon monoxide (CO) enters the picture, and
  through its very high affinity for hemoglobin,
  displaces the oxygen from the hemoglobin.
• This prevents oxygen being carried to the tissues
  and organs of the body.
• Carboxyhemoglobin is reddish in color.

7
Normal Physiology

• Oxygen is carried from the lungs by the blood
  hemoglobin to the tissues, here the beating heart
  is shown, and normal healthy oxidative metabolism
  goes on.

8
CO Poisoning

• During Carbon Monoxide poisoning, CO is carried
  from the lungs by the blood hemoglobin to the
  tissues, preventing oxygen from being carried,
  and blocking normal oxidative metabolism.

9
Symptoms of CO Poisoning
SpCO Level Clinical Manifestations
gt5 Mild headache
10 Mild headache, shortness of breath with exertion
10-20 Moderate headache, shortness of breath
20-30 Worsening headache, nausea, dizziness, fatigue
30-40 Severe headache, vomiting, vertigo, altered judgment
40-50 Confusion, syncope, tachycardia
50-60 Seizures, shock, apnea, coma
10
Caveat

• Symptoms DO NOT always correlate with the SpCO
  level
• If symptomatic, and exposed to CO, the patient
  should be transported to the hospital for
  definitive determination REGARDLESS of the CO
  level read by the Rad-57

11
The Rad-57

• Noninvasive measurement of both SpO2 (pulse
  oximetry) and SpCO (pulse CO-oximetry)
• DOES NOT REPLACE A GOOD ASSESSMENT

12
Indications

• Two settings for its use
• Screening patients for suspected exposure
• Screening emergency services personnel during
  rehabilitation
• Well first concentrate on the use of the device,
  then the specific protocol for each setting.

13
Using the Rad-57

• Connect the sensor cable to the Patient Cable
  Connector of the oximeter. Make sure the
  connection is secure and the cable is not
  twisted, sliced, or frayed.
• 2. Remove any substances (nail polish, paint,
  etc) on the patients second, third, or fourth
  digit that may interfere with the transmission of
  light between the sensors light source and photo
  detector.

14
Sensor Placement

• 3. Attach the sensor to the patient, applying it
  to the index (second), middle (third), or ring
  (fourth) digits. Only these digits can be
  accurately used by the CO-Oximiter.
• SENSOR PLACEMENT IS VERY IMPORTANT
• When possible, use ring (fourth) finger,
  non-dominant hand.
• Insert finger until the tip of finger hits the
  STOP Block.
• Sensor should not rotate or shift freely on
  finger.
• LEDs (red light) should pass through mid-nail,
  not cuticle.
• There is a top and bottom, cable should be on top
  (nail side).

15
Turning the device on

1. Press the Power button ON.

• POWER
• Press to turn ON.
• Press and HOLD to turn OFF.

• BATTERY INDICATOR
• 4 Green LEDs.
• Each represents 25 battery life.
• Use only Alkaline batteries.

16
Self-Test

1. The machine will go through a self-test procedure

• POWER ON SENSOR ON FINGER
• All LEDs light up.
• Calibration mode begins
• Spinning zeroes 0 - 0 0.
• Completed in 20 second (avg.)
• DO NOT move sensor during calibration.
• Acquires reading and displays.
• DISPLAY
• Defaults to pulse rate and oxygen saturation
  reading.
• PI bar graph displays strength of arterial
  perfusion.

17
Initial Display

• Oxygen Saturation on top in Red
• Pulse Rate on bottom in Green
• Green PI scale, indicates strength of arterial
  pulse
• Low SIQ LED indicates poor signal quality
• Press SpCO to display carboxyhemoglobin
• Press Bell to silence alarms

18
Measuring SpCO

• PRESS ORANGE SPCO BUTTON
• Display will toggle to CO mode for 10 seconds
• Carboxyhemoglobin reading in on top
• CO displayed on bottom confirming mode
• ALWAYS confirm high readings by taking several
  measurements on DIFFERENT fingers and average

• Real-time SpCO indicator continuously reads SpCO
• Green 1-9
• Orange 10-19
• Red 20 and above

19
Important Notes!

• The device is not approved for use in patients
  weighing less than 30 kg (66 lbs)
• When examining multiple patients, turn the device
  OFF then ON to recalibrate between patients.
• Failure to do so could give you incorrect
  readings!!!

20
Alarms

• When violated, audible alarm will sound,
  parameter will flash

• To adjust alarms
• Press Mode/Enter twice
• Press Next key to scroll through parameters
• Use up and down keys to adjust
• Reverts to Factory settings after turned off.

21
Care and Cleaning

• Once monitoring is complete, remove the sensor
  from the patient and turn the device off.
• Wipe the sensor and device with a soft cloth
  dampened with mild soap and water.
• Never submerge the sensor or the monitoring
  device.

22
The Low SIQ Indicator

• If the device indicates a Low SIQ, this refers
  to a low signal IQ and flashes when the SpO2 and
  SpCO measurements may be compromised. If this
  occurs
• Reassess the patient.
• Check the sensor to ensure it is properly applied
  to the patient and inserted into the Rad-57
  device.
• Determine if an extreme change in the patients
  physiology and blood flow at the monitoring site
  has occurred (e.g. an inflated blood pressure
  cuff, tourniquet, severe hypotension,
  hypothermia, or cardiac arrest).
• After completing this check, if the Low SIQ
  indication occurs frequently or continuously, you
  cannot rely on the device for either SpO2 or SpCO
  levels.

23
The Perfusion Index

• The Perfusion Index (PI) is a relative assessment
  of perfusion at the monitoring site.
• PI is displayed on a 10 segment LED bar on the
  right of the display ranging from lt0.1 (very
  weak perfusion) to gt5 (strong perfusion).
• The PI is shown as a bouncing bar indicator,
  where the peak of the bar coincides with the peak
  of an arterial pulsation.
• The highest LED will remain lit continuously to
  allow a PI level to be viewed.
• If evidence of low perfusion (lt1) is frequently
  displayed, find a better perfusion monitoring
  site and be sure the sensor is placed properly
  and there are no substances on the finger that
  could impede the emitter and photodetector.
• Very high ambient light situations can also
  produce falsely low PI.
• Should a low PI be persistent after these
  measures, review the procedure for Low SIQ.
• If a low PI still persists you cannot rely on the
  device for either SpO2 or SpCO levels.

24
Cyanide and Methemeglobinemia

• Cyanide toxicity and methemoglobinemia cannot be
  readily determined by this device.
• The CO-Oximeter should be used in addition to
  clinical judgment and a normal reading in the
  setting of a patient with severe respiratory
  distress or cyanosis should not rule out a
  significant oxygen-transfer deficit (cyanide,
  met-hemoglobinemia, sulfhemoglobinemia, or
  profound anemia) requiring aggressive airway
  management and high-flow oxygen.
• Always treat the patient first and not the
  reading on the CO-Oximeter.

25
Special note for Fire Personnel

• Unlike your gas meters, the RAD-57 is not
  intrinsically safe and should not be used in the
  presence of flammable substances!

26
What to do with the numbers

• The CO-Oximeter may be used on any patient
  greater than 30 kg where there is a concern for
  carbon monoxide exposure.
• For the non-rehabilitation scene, the following
  protocol applies

27
Using Pulse CO-Oximetry

• The SpCO reading is to be used as a screening
  measure.
• Definitive carboxyhemoglobin determinations are
  performed via blood draw in the hospital setting.
  
• Any patient with suspected carbon monoxide
  poisoning should receive oxygen by a
  non-rebreather mask until their CO level can be
  determined.
• Any patient with airway compromise, respiratory
  distress, or symptoms of significant carbon
  monoxide poisoning (nausea, vomiting, loss of
  judgment, chest pain, dizziness, muscle weakness,
  or a change in mental status) should be treated
  according to the MLREMS Standards of Care and
  transported with high-flow oxygen to an emergency
  department regardless of the SpCO reading.

28
Important Note!

• Pregnant women are at high risk in carbon
  monoxide exposure.
• The fetus is highly susceptible and the SpCO may
  be 10-15 higher than maternal readings.
• All pregnant women with possible CO exposure
  should be transported to the emergency department
  for evaluation.

29
Who goes to the hospital?

• Any patient with a SpCO reading gt12, even if
  without symptoms, should be transported with
  high-flow oxygen to an emergency department.
• Any patient with a SpCO reading gt25, even if
  without symptoms, MUST be transported with
  high-flow oxygen to an emergency department.

30
Who can appropriately not be transported?

• Patients with carbon monoxide exposure and SpCO
  lt25 may be treated and released provided the
  following conditions are met
• The patient is asymptomatic.
• The patient exhibits no signs of respiratory
  distress, and pulse oximeter reading is above
  92.
• The SpCO must be below 5 in non-smokers, and 10
  in smokers.
• The lungs are clear on auscultation.
• There are no other significant burn or traumatic
  injuries.
• Both the pulse oximetry and the CO levels must be
  documented.
• The patient has medical decision making capacity
  per the MLREMS Refusal of Care Policy.

31
Documentation

• Use of the Rad-57 and serially recorded SpCO
  levels should be documented accordingly in the
  Prehospital Care report.
• It cannot be emphasized enough that the patients
  clinical presentation is what should drive
  routine medical care and not the SpCO level
  observed.
• If there is ever doubt regarding the patients
  disposition, provide high flow oxygen and
  transport to the hospital for evaluation.

32
Use in the Rehabilitation Sector

• When available, the use of pulse CO-oximetry is a
  valuable adjunct to assessment during
  rehabilitation.
• The use of hand-held pulse co-oximetry devices is
  optional, and not required for Incident
  Rehabilitation.

33
Use in the Rehabilitation Sector

• The SpCO reading is to be used as a screening
  measure.
• Definitive carboxyhemoglobin determinations are
  performed via blood draw in the hospital setting.
  
• Any patient with complaints of chest pain,
  shortness of breath, or altered mental status
  should receive oxygen by a non-rebreather mask
  and moved to the Treatment Area, regardless of
  SpCO reading.

34
Use in the Rehabilitation Sector

• If SpCO lt5 and vital signs are within normal
  limits, the provider is encouraged to drink at
  least 16 ounces of fluid and may return to
  manpower/staging after a minimum of 10 minutes
  rest.
• If SpCO 5 and lt12, the responder may breathe
  ambient air and may not leave the rehabilitation
  area until their CO level is below 5.
• If SpCO 12 the responder should be moved to the
  Treatment Area and receive high-flow oxygen until
  the SpCO is lt5.
• If SpCO 25, the responder will be moved to the
  Treatment Area and transported with high-flow
  oxygen to an emergency department.

35
Documentation

• Documentation of SpCO levels can be made on the
  rehabilitation log.
• Responders moved to the treatment area should
  have values recorded on the prehospital care
  report.

36
Hyperbarics?

• The Monroe-Livingston Region does not have the
  services of a hyperbaric chamber, often used for
  treating life-threatening CO poisoning.
• All unstable patients with suspected CO poisoning
  should be transported to the nearest appropriate
  local facility for stabilization and serum
  carboxyhemoglobin determination.

37
Conclusions

• The Rad-57 is an important device to be used in
  the evaluation of patients with suspected CO
  poisoning.
• Proper use of the device is imperative to assure
  adequate readings.
• Readings provided by the device should NEVER
  override clinical assessment treat the patient,
  not the CO-oximeter!