For the EMT-Basic

Objectives Understand ALCO regulations relative to monitoring

pulse oximetry by the EMT-B

Review the signs and symptoms of respiratory compromise.

Understand the importance of adequate tissue perfusion.

Understand circumstances that hinder/prevent SpO2 readings.

ALCO Regulations Protocol pg. 47

Allows EMTs to monitor saturation of arterial oxygen levels of blood by way of pulse oximetry.

Falls under “Baseline vital signs”

What is it used for?

Respiratory Compromise Signs and Symptoms

Dyspnea

Accessory muscle use

Inability to speak in full sentences

Adventitious breath sounds

Increased or decreased breathing rates

Shallow breathing

Flared nostrils or pursed lips

Retractions

Upright or tripod position

Hypoxemia Causes lower oxygenation in arterial blood

Results in decreased cellular oxygenation

Anaerobic metabolism

Creates energy through the combustion of carbohydrates in the absence of oxygen

Loss of cellular energy production

Hypoxemia Etiology Inadequate External Respiration (in lungs)

Decreased on-loading of oxygen at pulmonary capillaries

Inadequate Oxygen Transport

Decreased oxygen carrying capacity

Inadequate Internal Respiration (in Metabolizing tissue)

Decreased off-loading of oxygen at cellular capillaries

What are some causes of Hypoxemia?

Inadequate Oxygen Diffusion Pulmonary edema

Fluid between alveoli and capillaries inhibit diffusion

Pneumonia Reduces the surface area of

respiratory membranes

Reduces the ventilation-perfusion ratio

COPD Air trapping in alveoli

Loss of surface area of respiratory membranes

Inadequate Oxygen Transport Anemia

Reduces red blood cells oxygen carrying capacity

Inadequate hemoglobin results in the loss of oxygen saturation

Poisoning Carbon monoxide attaches to hemoglobin more readily

preventing oxygen saturation and oxygen carrying capacity

Shock Low blood pressures result in inadequate oxygen

carrying capacity

What should I look for?

Signs and Symptoms of Hypoxemia Restlessness/ Anxiety

Altered or deteriorating mental status

Increased or decreased pulse rates

Increased or decrease respiratory rates

Decreased oxygen oximetry readings

Cyanosis (late sign)

How to Monitor Sp02

Technology The pulse oximeter has Light-emitting diodes (LEDs)

that produce red and infrared light

LEDs and the detector are on opposite sides of the sensor

Sensor must be placed so light passes through a capillary bed Requires physiological pulsating waves to measure

saturation

Requires a pulse or a pulse wave (Adequate CPR)

Measuring Sp02 Oxygenated blood and deoxygenated blood absorb

different light sources

Oxygenated blood absorbs more infrared light

Deoxygenated blood absorbs more red light

Pulse oximetry reveals arterial saturation by measuring the difference.

Oxygen Saturation Definition: Percentage of hemoglobin saturated with

oxygen

Normal SpO2 is 94-99%

Suspect perfusion compromise if less than 94% SpO2 in individuals with no known Respiratory Illness

COPD Patients should have a resting SpO2 within a range of 88%-92% per county protocols.

Conditions Affecting Accuracy What to watch for:

Fingernail polish and pressed on nails

Dark Pigmentation of skin: Apply sensor to the fingertips of these patients (upside down).

Poor circulation in elderly patients

Hypothermia

Possible CO poisoning

Diabetes

Hypotension

Interpreting Pulse OximetryAssess and treat the PATIENT not

the oximeter! Use oximetry as an adjunct to patient assessment

and treatment evaluation

NEVER withhold oxygen if the patient has signs or symptoms of hypoxia or hypoxemia regardless

of oximetry readings!

Documentation Pulse oximetry is usually documented as SpO2

Document oximetry readings as frequently as other vital signs

When oximetry reading is obtained before oxygen administration, designate the reading as “room air”

SummaryAs with all monitoring devices, the interpretation of information and response to that interpretation is

the responsibility of a properly trained technician!