A patient safety alert has been issued by regulators on the risk of harm from the inappropriate placement of pulse oximeter probes in the health service in England.
NHS Improvement warned that readings could be highly inaccurate when probes meant for the ear and finger were mixed up or when devices were used to measure the wrong patient age group.
“Adult oximeter probes can be attached to either a finger or an ear”
As a result, the regulator has instructed trusts to develop an action plan by June to reduce the risk of the inappropriate placement of pulse oximetry probes.
“Adult oximeter probes can be attached to either a finger or an ear, but are not interchangeable between these sites, whilst probes for babies and children need to be selected according to the patient’s weight,” the patient safety alert noted.
It said: “If an oximeter probe intended for the finger is attached to the ear (or vice versa), or a probe intended for an adult is attached to a baby or a child (or vice versa), it can produce a reading up to 50% lower or 30% higher than the real value.”
It warned that the clinical implication was that staff may be “falsely reassured about a patient’s condition, when in reality the patient is deteriorating, or may make an inappropriate intervention when in fact a patient is stable or improving”.
NHS Improvement said it had previously been made aware that the issue may be under-recognised in the NHS and subsequently carried out a survey of 81 clinical staff and observed clinical practice.
Key issues identified were that a substantial proportion of staff did not know that finger probes can give misleading results if attached to ears.
In addition, a quarter said they did not have access to probes specifically for the ear, even though in almost all clinical settings some patients will need them.
They survey also found that once probes were removed from their packaging there was no easily visible prompt to remind the user where to attach the probe.
Meanwhile, it indicated that staff may not be aware of other factors that can affect the accuracy of the reading.
The “scale of these gaps in knowledge and equipment suggests the potential for severe patient harm is high”, warned the safety alert from NHS Improvement.
The local actions required by the alert will “help reduce the risk of incorrect probe selection and placement”, it stated.
NHS Improvement and the Medicines and Healthcare products Regulatory Agency are also asking manufacturers to review device labelling and provide prompts for correct attachment.
Earlier this year, researchers in Ireland concluded that nail treatments do not affect readings of patients’ oxygen levels, despite widespread concern.
Their study found that, contrary to previous thinking, nail treatments such as acrylic nails or nail polishes did not affect readings from digital pulse oximetry devices used in hospitals.