Pulse Oximetry

What is Pulse Oximetry Pulse oximetry is a non-invasive means of measuring oxygen saturation of arterial blood. Oxygen saturation is defined as the amount of hemoglobin that is bound to O2 divided by the amount of total hemoglobin that is available to bind with O2.

What is Pulse Oximetry? It uses two wavelengths of light to measure the saturation of oxygen. The lights shine through the vascular bed and measure the saturation via a probe. Probe placements include: thumb, finger, bridge of nose, ear and for children the foot and hand. No calibration is required for the equipment. Advantages to pulse oximeters are rapid response, non-invasive, and accuracy.

What is a Pulse Oximeter? A device that provides a non-invasive (does not break the patient’s skin or body openings) method of allowing the monitoring of the amount of oxygen of a patient's hemoglobin.

What does Pulse Oximetry do? Allows for further assessment of a patient’s respiratory status. Let’s the evaluator know how much oxygen is flowing in a patient’s blood. Is an indicator that a patient may be suffering from a more serious condition involving the cardiac and/or respiratory systems.

When do I Use a Pulse Oximeter? Pulse oximetry may be performed to assess the adequacy of oxygen levels (or oxygen saturation) in the blood in a variety of circumstances such as: surgery, other procedures involving sedation (for example, bronchoscopy) adjustment of supplemental oxygen as needed effectiveness of lung medications and patient tolerance to increased activity levels.

Other reasons may include, but are not limited to, the following: Recovery from a surgery requiring general anesthesia. Whenever the physician orders it. Patient has complaints of shortness of breath (SOB). When the patient has signs and symptoms of hypoxia. Patient exhibits signs and symptoms of myocardial infarction. Patient has a disease/disorder involving the respiratory system Patient has an order to wear an oxygen appliance.

How Do I Use a Pulse Oximeter? Wash your hands! Take off any nail polish. The pulse oximetry does not work as effectively if placed on a finger with nail polish. Place the device on a finger. There are different types of finger probes. Some wrap around the finger. It’s important the finger comes in contact with the sensor which is usually indicted by a red light. The index finger or ring finger usually work best.

How Do I Use a Pulse Oximeter? 3. Stay still and wait for a reading. Moving your hand, fingers or arm will interfere with getting an accurate reading. Rest your arm on something firm to prevent it from moving. Remain still until a number appears on the device. 4. Be patient. The sensor may take anywhere from a few seconds to a minute to determine a reading. Some devices will have a green light flashing which indicates the sensor is working and will give a readout. If the light is flashing red it may indicate the device cannot get a reading.

How Do I Use a Pulse Oximeter? 5. Understand results. The amount of oxygen in the blood is given in a percentage. For example, if the reading is 100% your blood is saturated with oxygen at 100% which is as high as it can get. Most people who are healthy will have a reading of 90%or greater. 6. Document your findings on the Patient Contact Sheet.

What Reading Should I Get? Most people who are healthy will have a reading of 90 percent or greater.

Importance as an assessment tool? Helps to monitor oxygen levels in patients receiving O2 therapy. Let’s medical staff know if O2 prescribed is not enough to relieve the patient’s symptoms. Let’s the medical staff know when O2 levels are reached/maintained.

Importance as an assessment tool? Let’s the medical staff know if the patient’s O2 level drops when the patient performs activities. Mechanical ventilation: Use of a ventilator to support breathing. Sleep apnea: Periods of cessation of breathing during sleep. Medical conditions: heart attack congestive heart failure chronic obstructive pulmonary disease (COPD) anemia lung cancer asthma pneumonia

Limitations/Errors of Use of the Pulse Oximeter? The pulse oximeter is only one tool that helps in the assessment of a patient’s respiratory status. Nail polish will alter the readings. Will not get accurate results in patients with peripheral artery disease (poor circulation in the extremities). The monitor must be checked regularly to ensure it is working properly. If it is not checked regularly, results may not be accurate!!!!

Limitations/Errors of Use of the Pulse Oximeter? Improper probe placement – low numbers Severe anemia (decreased red blood cells) Hypothermia (decreased perfusion) – low numbers Vasopressor drugs (vasoconstriction) – low numbers Stray ambient light (sun light, bili light) – low numbers Low Light transmissions (edema, dark skin, nail polish, nail coverings) – low numbers

OXYGEN DELIVERY SYSTEMS Nasal Cannula Simple face mask Partial Non Rebreather Non Rebreather

Nasal Cannula

Oxygen Therapy – Delivery Systems Nasal cannula A disposable 2-pronged plastic device which is inserted into the nares. Attached directly to a flowmeter and/or humidifier Humidifier is not necessary at flows of 4 lpm or less A humidifier is used > 4 lpm to prevent nasal dryness Range of us up to 6 lpm Benefits: Simple, inexpensive, client can talk freely Risks: May cause necrosis of nares and/or ears

Oxygen Therapy – Delivery Systems The most commonly used reservoir systems. Three types Simple O2 mask Partial rebreather mask Non-rebreather mask A disposable plastic unit which covers nose & mouth Body stores oxygen in between breaths Patient exhales directly thru port holes Normal flow range? 5-12 lpm 35-50%

Simple oxygen mask

Oxygen Therapy – Delivery Systems Partial rebreathing O2 mask Similar to simple mask with addition of a reservoir bag Bag collects first portion of exhaled oxygen (dead space) Normal flow? 6-10 lpm Total Oxygen delivery 35-60% Non rebreather O2 mask Addition of a one-way valve between bag & mask Normal flow? > 10 lpm 55-70% (or higher)

Partial and Non Rebreather

Oxygen Therapy – Delivery Systems Non-rebreathing reservoir circuit A more elaborate system for delivery From 21% to 100% Utilizes large-bore aerosol tubing Air is often warmed & humidified May be used on … a spontaneously-breathing patient via a mask an intubated patient via endotracheal or tracheostomy tube