NCLIN 301 Pulse Oximetry

The nurse is using a pulse oximeter to monitor a client's oxygen saturation following abdominal surgery to ensure adequate oxygenation. The health care provider has set a parameter of 92%. How would the nurse maintain this parameter?

A: Adjusting the flow of oxygen to maintain an oxygen saturation level at or above 92%. Rationale: The health care provider sets the parameter to ensure that the client maintains the desired level of saturation, in this case 92% or higher. To ensure adequate oxygenation for the client, the nurse titrates the flow of oxygen based on the pulse oximeter measurement to maintain 92% saturation or above. A constant flow of oxygen is desired to maintain the saturation level, not applying and removing the oxygen as needed.

What would the nurse use to prepare the site for attachment of a pulse oximeter probe?

A: Alcohol wipe Rationale: The nurse prepares the site for the probe by cleansing it with an alcohol wipe. This sufficiently cleanses the area since the probe is non-invasive.

The nurse is using a pulse oximeter to monitor a client who is receiving oxygen therapy via a nasal cannula. The nurse explains to the client that which factor might affect the results of pulse oximetry?

A: Alterations in circulation. Rationale: The results of pulse oximetry can be altered by several factors, including alterations in circulation, movement of the client, or various substances depending on the model of the oximeter being used. Cardiovascular disease, thyroid disease, and pain medication do not alter the results of a pulse oximeter.

What assessment would the nurse make prior to using a pulse oximeter to measure oxygen saturation?

A: Capillary refill Rationale: The nurse should assess the pulse nearest to the monitoring site (the wrist) and capillary refill prior to using a pulse oximeter. Brisk capillary refill and a strong pulse indicate that circulation to the site is adequate. Blood pressure and respiratory rate are not monitored at this time.

The nurse has attached the probe of a pulse oximeter to the finger of a client to monitor oxygen saturation. The nurse notices that the oximeter reads a low saturation of 88 percent with irregular meter pulsations; however, upon assessment of the client, the nurse finds no symptoms of respiratory distress. What might be causing this failure to obtain an accurate reading?

A: Peripheral vascular disease Rationale: When a client has peripheral vascular disease, the circulation in the hands is compromised. In this situation, the earlobe site should be used for the probe to obtain an accurate reading. An irregular pulse would not affect the oxygen level. With a pulmonary embolism and accumulation of secretion in the lungs, the client would show systems of respiratory distress, which was not the case.

The nurse is preparing the site for applying the probe of a pulse oximeter. What would the nurse do to ensure accurate results?

A: Remove any nail polish on the client's fingers. Rationale: When preparing the site for the pulse oximeter probe, the nurse would check if the client has nail polish or fake fingernails applied on the nails. These substances could alter the results of some models of pulse oximeters. The site is prepared by using an alcohol wipe, not lotion or powder. Deodorant does not affect the results of the pulse oximeter.

The nurse on a telemetry unit is assessing oxygen saturation of a client admitted with severe peripheral edema using a pulse oximeter. The nurse obtains a weak and inaccurate pulse oximeter reading. What actions constitute the correct response by the nurse? Select all that apply.

A: Request a prescription for an arterial blood gas level by the lab, use an ear pulse oximeter probe on one of the client's ears. Rationale: The nurse should first use an ear pulse oximeter to try to get a more accurate reading. If that is not effective and an accurate oxygen blood saturation is required, the nurse could request an arterial blood gas test. Decreased arterial blood flow to the extremities from edema could influence the accuracy of the reading if it is performed peripherally on the fingers or toes.

The nurse is turning on the pulse oximeter and notices a bar form on the machine. What does this bar represent?

A: Signal strength. Rationale: The pulse oximeter machine has a bar or wave form on the front of the machine that indicates the signal strength. The hemoglobin level is not tested by the pulse oximeter. The oxygen level and pulse rate are shown as numbers on the machine.

The nurse is checking capillary refill to measure circulation in the client's index finger prior to using a pulse oximeter. What would be the next best site to place the probe if circulation is found to be inadequate at this site?

A: The bridge of the nose Rationale: If circulation is inadequate at the site, the nurse could use the earlobe or bridge of the nose. These alternate sites are highly vascular alternatives. If these were unavailable, the nurse would use a toe only if lower extremity circulation is not compromised. Peripheral vascular disease is common in lower extremities. The probe is not designed for use on an elbow.

The nurse is using a pulse oximeter to measure the oxygen saturation for a client with lung cancer. Normally, where would the nurse place the probe of the device?

A: The index finger Rationale: The probe of the oximeter is designed to fit over the client's index finger, which is the most accessible site. If one finger is too large for the probe, another finger can be used.

The nurse is checking a client's oxygen saturation level using a pulse oximeter. How should the probe be placed on the finger?

A: With the light-emitting sensor and light-receiving sensor opposite each other. Rationale: When placing the probe of a pulse oximeter on the client's finger, the nurse must ensure that the light-emitting sensor and light-receiving sensor are aligned opposite each other. Secure attachment and proper alignment promote satisfactory operation of the equipment and an accurate reading of the oxygen saturation level. It is not necessary to check this alignment if the probe is placed on the forehead or bridge of the nose.

A nurse takes a client's pulse oximetry reading and finds that it is normal. What does this finding indicate?

A:The client's available hemoglobin is adequately saturated with oxygen. Rationale: Pulse oximetry is a noninvasive technique that measures the arterial oxyhemoglobin saturation (SaO2 or SpO2) of arterial blood. This test measures only the percentage of oxygen carried by the available hemoglobin. Thus, even a client with a low hemoglobin level could appear to have a normal SpO2 because most of that hemoglobin is saturated. However, the client may not have enough oxygen to meet body needs. A normal pulse oximetry reading does not necessarily indicate a normal RBC count or heart rate.