Pulse Oximeters – Errors and Troubleshooting

While using a pulse oximeter, it is inevitable that errors and problems may sometimes occur. However, most of them can be fixed in a simple and effortless manner. Here are the common problems encountered when using a pulse oximeter and how to solve them.

Failure to obtain a signal

In order to get a reliable and continuous signal, the measuring site must be kept clean and dry. You may reposition the user’s finger. Sometimes, there might be a need to change the monitoring site. If this doesn’t solve the problem, the person’s vital signs should be assessed including the measuring site, whether there is adequate blood flow. The sensor and a blood pressure cuff must not be placed on the same hand. In addition, check for loose wirings or whether the probe is properly attached to the base unit that should be connected to a power source.

Alarm Problems

A common problem encountered when using a pulse oximeter is that the alarm keeps setting off, which is more annoying than useful. This typically occurs when the set is not motion-resistant and excessive movement can trigger the alarm. Check your device manual for this feature. The best way to deal with this is to assess the patient for any other cause of the problem, as well as the device. Some alarms may be turned off, but that is not really helpful as alarms warn you whether the patient is already hypoxic. You may set the alarm limits according to you facility’s policy.

Error Messages

Many pulse oximeters can display on their screen certain error messages. Read the user’s manual in order for you to familiarize these messages and the appropriate troubleshooting steps. Some units may already display troubleshooting tips on its screen.

Erroneous Readings

There are a variety of reasons why a pulse oximeter obtains erroneous readings.

• Room temperature may be one of the reasons behind such. Refer to the user’s manual about appropriate room temperature for optimal functioning.

• Venous pulsation brought about by tricuspid regurgitation or pulmonary hypertension and a tight finger probe may cause erratic SpO₂ readings.

• Additionally, compromised blood flow to the monitoring site may also cause problems. Although many monitors nowadays are equipped with the latest digital signal technology that can detect oxygen saturation even when there is low perfusion, the patient should still be assessed for the cause of blood flow restrictions such as blood pressure cuffs and tight restraints. Check the actual pulse rate from the pulse rate that is being displayed on the unit. If the rates don’t match, the saturation reading cannot be considered accurate. Reposition the probe or change the measuring site as necessary.

• Medical conditions such as elevated carboxyhemoglobin and methemoglobin levels may cause a falsely high oxygen saturation reading. In such scenarios, refer the condition with the physician. A pulse CO-oximeter may be replaced.

Refer to the user’s manual for more troubleshooting tips.