Measuring oxygen saturation in homecare

Not only has COVID-19 brought with it unprecedented changes to everyday lives, but it has also highlighted simple observations in healthcare. Oxygen saturation levels are key to monitoring respiratory health decline as a result of a range of respiratory diseases and infections, with COVID-19 being the deadliest of these. It is, therefore, of paramount importance that oxygen saturation levels are checked regularly in the community, at home and in residential care settings, not just in the hospital. These levels are often taken when carrying out routine pulse oximetry in homes, but it is important to refresh community nurses' awareness of the value of these mesaurements and update guidelines on their recording.

Pulse oximeters are medical devices that monitor the level of oxygen in a patient's blood and alert the healthcare worker if oxygen levels drop below safe levels, allowing rapid intervention. These devices are regarded as essential in any setting in which a patient's blood oxygen levels requires monitoring, such as during operations, emergency and intensive care, and treatment and recovery in hospital wards (WHO, 2020).Box 1 provides examples of oximeters commonly used in various healthcare settings, including community settings, in the UK. The pulse oximeter should be cleaned between each patient within multi-patient settings and on return from a home care setting, and following decontamination equipment that is returned from residential care settings will need to be checked before it is used again, to ensure it is working correctly (NHS England, 2020).

Box 1.Pulse oximeters commonly used in the UK

The London-wide Local Medical Committee (LMC) (2020) noted that COVID-19 is a new condition, still requiring learning as to the best way of assessing its severity in the community. It is known that pulse oximetry can be a useful aid to clinical decision-making, although it is not a substitute for a clinical assessment, nor sufficient for diagnosis by itself (LMC, 2020). Pulse oximetry may be useful in triaging potentially hypoxic patients in the home or GP surgeries/assessment centres, in order to help determine which patients require further assessment or treatment. Pulse oximetry is helpful in assessing the severity of the condition and, in assisting with other criteria, to determine whether or not to refer patients for further assessment and/or treatment. Of course, there are other causes of hypoxia that should be considered in the differential diagnosis apart from COVID-19 infection. It may aid the monitoring of patients who have been discharged from hospital following a diagnosis of COVID-19 infection but who are now deemed well enough to return home. It is important to note that residents who have underlying respiratory disease such as chronic obstructive pulmonary disease (COPD) will have a naturally lower oxygen saturation limit and, therefore, would be deemed clinically not as unwell necessarily, as someone with the same lower saturation who has no underlying respiratory pathology.

Recognising the unwell person

According to the British Geriatrics Society (BGS) (2020), Public Health England (PHE) has suggested that COVID-19 should be suspected in any person with a new continuous cough and/or a high temperature of at least 37.8 degrees, but that COVID-19 cases among care home residents often manifest non-respiratory symptoms, for example, worsening or new confusion, or even diarrhoea. Therefore, it is extremely important that staff are aware of this when looking at the patient's overall presentation. Staff in care homes are well placed to recognise this happen, as they often know the residents very well.

Suspected COVID-19 cases

Where community nurses suspect COVID-19, they should isolate that person, and for that patient, should start using personal protective equipment (PPE) provided by NHS England, which consists of gloves, aprons and face masks (BGS, 2020). PPE requirements for care home staff are the same as those for hospital staff on general wards. Following the identification of a suspected case, the local PHE contact should be notified, and, if care home staff are unable to contact this person, they should contact their allocated GP or delegated primary care health professional, who will advise on the medical treatment plan and isolation requirements, to prevent further transmission of COVID-19. These requirements will change over time with the evolving situation. The BGS (2020) also noted that GPs and primary care teams should recognise that care homes are community-based health and social care facilities and assist them to gain access to the advice they need as quickly as possible. Care homes are often mis-perceived as non-clinical environments, and health practitioners should be reminded that they can be used to help the primary care staff not only for infection control and prevention, but also for tracking and care of COVID-19 patients.

NHS England pulse oximetry advice

NHS England (2020) noted that patients should be monitored for ‘silent hypoxia’-asymptomatic presentations with low oxygen saturations, often accompanying normal respiratory rate, heart rate and other observations.

Patients should be managed in primary care in accordance with the policies set out in the general practice standard operating procedure, and that following assessment using the total triage model, an assessment should be carried out using pulse oximetry (NHS England, 2020). In ambulatory patients, triaged patients should be assessed on site, alongside guidance and protocols that assure patients with and without symptoms of COVID-19 are kept separate from each other.

Vulnerability to COVID-19 in residential care

Approximately 400 000 older people in the UK live in care homes, with a significant proportion of these living with frailty (BGS, 2020). The BGS (2020) also noted that this is a bed-base three times the size of the acute hospital sector in England. Many residents in care homes have cognitive impairment and a considerable amount of comorbidities, alongside physical dependency, making them highly at risk of the most severe effects of COVID-19. Many are also palliative. Outbreaks in care homes have been shown to be devastating. and it is obvious that care home residents have a particularly poor prognosis if they become hypoxic secondary to COVID-19 (BGS, 2020). Another factor to consider is that COVID-19 can rapidly overwhelm healthcare systems, preventing them from being able to deliver even the most basic care, and, while many care home staff are trained in recognising and being able to manage acutely unwell residents, this is not universally the case, especially in care homes without nursing (BGS, 2020). Healthcare assistants are, however, especially trained in these environments to manage those with cognitive impairment and behavioural symptoms, being especially experienced and skilled in providing end-of-life care (BGS, 2020).

Observations in care home settings

Care homes, particularly those without nurses, have often not been required to undertake observations on residents. However, the BGS (2020) stated that, in the context of this outbreak, trained staff are available at all care homes who have the ability to take a person's temperature using a tympanic thermometer (one inserted into the ear), which is necessary to diagnose the illness and is an absolute requirement.

The skills and equipment needed to measure heart rate and blood pressure and pulse oximetry are certainly considered a useful adjunct, and care homes should, where possible, ensure that the equipment required is available, and that staff have the correct competencies for complete these mesaurements (BGS, 2020).

Pulse oximetry

The RCN (2020) noted that reduced levels of oxygen circulating in the bloodstream can lead to very serious, even fatal, complications for the heart, lung, brain and other organs. It appears that the levels can falls in a person with COVID-19 despite them not outwardly showing other significant symptoms, such as fever and severe breathlessness. This decline can be detected in the patient by recording their oxygen levels.

Many people are at risk of developing reduced levels of circulating oxygen. Those who have severe lung or heart disease, who are unconscious or who have difficulty breathing, or those who need oxygen treatment for any reason are all at risk of reduced oxygen levels, meaning they could become seriously unwell (RCN, 2020). It is also well-documented that more fatalities from COVID-19 appear to be in those with respiratory or cardiac disease (Palmer, 2020). It is, therefore, crucial that these patients who are at an even higher risk of the deadly effects of the virus are identified and monitored regularly. For those who are coming back into the homecare setting after a hospital stay for COVID-19 treatment, it is important that their oxygen saturation levels are monitored as they are likely to have significant respiratory injury from the effects of the virus and will possibly require further oxygen therapy in the homecare setting.

Care plans need to be tailored to suit the individual's needs as to their risk of the effects of the virus, the effects the virus may have already had on them, and also considering that all clients need some form of monitoring in case they contract the infection, whether or not they are in the most vulnerable categories.

Normal oxygen saturation levels are between 95% and 100%, although this varies depending on the person's age and general condition. A level below 90% is considered a cause for alarm and will need prompt attention, while abnormally high levels may suggest that the person is receiving too much oxygen therapy (RCN, 2020); for example, it would be considered that saturations are too high if above 92% in a patient with severe COPD, as it is normal for this type of patient to maintain their saturations at a lower level. The chart used to document the observations must be completed accurately, and it should also be noted that, if someone is receiving oxygen therapy, it is important to take that into account when considering the overall clinical presentation of the patient (RCN, 2020). Previous results can be used for comparison.

Pulse oximeters are used to record oxygen saturation levels in a variety of care settings

KEY POINTS

• Care homes contain three times as many patients as hospital acute settings
• These patients are often highly vulnerable, with physical, cognitive and mental impairment, making them more susceptible to the more severe effects of COVID-19
• A patient in a care home with COVID-19 may become more confused, or have diarrhoea, as opposed to breathlessness, in the early stages
• All care staff should be trained in pulse oximetry recording and monitoring
• GPs and other clinicians can remotely monitor patients who are having their oxygen levels monitored by themselves or their carer
• Factors that prevent accurate pulse oximetry readings include bright sunlight, cold temperatures, and nail varnish

CPD REFLECTIVE QUESTIONS

• Write a reflection of how you monitored and managed a patient with low oxygen saturations, noting what other monitoring equipment and treatment was required
• List the basics in spotting the deteriorating patient and how the COVID-19 patient can present initially in a variety of ways
• What is it about community patients that may be different in terms of COVID-19 presentation?

Teaching shielding patients and carers to assess oxygen saturations using pulse oximetry

Housebound or shielding patients should have pulse oximeters delivered to them, and a volunteer may be needed to assist with ulse oximetry or calibration of the device, with referrals for support being able to be made via the NHS Volunteer Responders portal. The patient should then be contacted to get their oxygen saturation readings (at rest or, where appropriate, on exertion) or arrange for these to be phoned through. In order to make sure that vulnerable people living at home with care packages in primary care, for example, correctly assess their oxygen levels, written instructions for how to use a pulse oximeter and record oxygen saturations can be included in a diary (NHS England, 2020). A video consultation may also be appropriate to help the patient learn how to use the oximeter. If patients rely on carers to assist in taking measurements, it may be considered appropriate to support carers, to put in place infection prevention and control procedures (NHS England, 2020). When managing the health of a patient or resident remotely, the frequency of follow-up should be at the discretion of the clinician, usually the GP. When home monitoring of pulse oximetry is possible, a diary should be considered, allowing oxygen levels and function to be recorded in order to be analysed and compared according to the clinical presentation overall (NHS England, 2020). Patients should be talked through the warning signs that require escalation, and they should be instructed to contact their clinician if their condition deteriorates.

Limitations in pulse oximetry

It is important to be aware that nail polish, dirt and artificial nails can cause low or no readings when oxygen saturations is measured using a pulse oximeter; therefore, these should be removed prior to assessment (Local Medical Committees (LMC), 2020). Poor perfusion (due to hypotension, hypovolemic shock or a cold environment), movement including shivering, heart arrhythmias or cardiac failure may also result in the pulse oximeters not providing a reading, as they are unable to identify an adequate pulse signal (LMC, 2020). Bright artificial light (such as in an operating room or bright sunlight) can also cause false low readings, which is important to considered when assessing the oxygen levels using a pulse oximeter (LMC, 2020).

Conclusion

With the increasing demand for bed spaces in hospital for COVID-19 patients, it is important that, in the care home environment and community settings, staff are equipped to spot early warning signs such as oxygen desaturation, be aware of aftercare for a COVID-19 patient coming back from hospital, and to know about how to manage the isolation of the newly recognised COVID-19 patient and what to do next. Clearly, oxygen saturation levels are a simple yet vital measurement to take using a straightforward device, and, if all staff have fundamental training in what the results mean and when to use the device more often, deterioration of the COVID-19 patient may be prevented or the disease might be managed more successfully.