THE CDC ADVISES patients with confirmed COVID-19 to remain at home and utilize telehealth services, if available, unless they begin to experience signs and symptoms of deterioration, such as dyspnea, chest discomfort, confusion, cyanosis, and difficulty waking or staying awake.1 However, a recent multinational study described patients with COVID-19 who presented with hypoxemia but without signs of respiratory distress initially, many of whom went on to develop respiratory failure.2,3 Also called silent hypoxemia, this sign cannot be assessed via telehealth services unless the patient can determine his or her percentage of saturated hemoglobin in the capillary bed (SpO2) and interpret the findings correctly.2,4 This article discusses how using pulse oximeters at home in combination with telehealth services can help healthcare professionals assess some aspects of a patient's cardiopulmonary function virtually and determine whether a higher level of care is warranted.
Self-monitoring with pulse oximetry
For high-risk patients at home, pulse oximeters can detect deterioration in SpO2, a possible sign of severe COVID-19 that may require immediate intervention. Prompt treatment may decrease disease severity and prevent the need for mechanical ventilation.5,6
Patients with COVID-19 who are at an increased risk of developing severe disease include those who are over age 65, long-term-care residents, and immunocompromised patients, as well as those with chronic lung disease or moderate-to-severe asthma, chronic heart disease, severe obesity, diabetes, chronic renal disease, and hepatic disease.1 Severe COVID-19 places these individuals at a higher risk for endotracheal intubation and death.3
Current data suggest that severe complications of COVID-19 typically occur between the 5th and 10th day of symptom onset.3 Although signs and symptoms vary among patients as the disease progresses, multiple studies have identified silent hypoxemia as a common finding.2,7 Patients who are hypoxemic without dyspnea may be overlooked, particularly if they are receiving care via telehealth.
By using an at-home pulse oximeter to assess SpO2 levels, patients with COVID-19 who are at higher risk for severe disease can self-monitor their clinical status and alert healthcare providers of significant changes, triggering a higher level of care if indicated. These patients should receive education and training on the proper use of pulse oximeters from a home healthcare nurse or telehealth nurse, including the positioning of the device on the finger and the interpretation of SpO2 and pulse rate. Home-use pulse oximeters can be obtained from medical supply companies with a healthcare provider's prescription, and the cost may be covered by health insurance.
A student's experience
As a nursing student, I knew seven individuals with confirmed COVID-19 infections, three of whom met the CDC criteria to be considered high-risk for developing severe disease. Each of these individuals participated in regular telehealth services to determine their medical status.
The three high-risk patients were eventually hospitalized: one required endotracheal intubation; one required high-flow oxygen therapy; and one required low-flow oxygen therapy. Each was administered remdesivir, a novel drug under investigation to reduce the prevalence of intubation and the need for ICU treatment, decrease lengths of stay, and improve survival in patients with severe COVID-19.1,6-8 The CDC recommends remdesivir for patients who require low-flow oxygenation only, but it is not recommended for patients on any other form of oxygenation.6 Early identification of patient deterioration using home-use pulse oximetry may allow for treatment with remdesivir if COVID-19 is detected before invasive ventilation, bi-level positive airway pressure, extracorporeal membrane oxygenation, or high-flow oxygenation is needed.6-8
I directly assessed one of these patients, indirectly assessed another, and did not assess the individual who required endotracheal intubation.
The patient who required low-flow oxygen presented with a respiratory rate of 26, an SpO2 level of 85% on room air, a heart rate of 118 beats/minute, dyspnea, and wheezing upon auscultation. After contacting telehealth services for guidance, this patient had reported no signs and symptoms of severe COVID-19. I communicated the assessment findings to a nurse, who immediately talked to a provider who recommended emergency treatment.
The second patient was not dyspneic upon arrival in the ED and had not displayed other signs or symptoms of hypoxemia during multiple telehealth calls. This patient's SpO2 level was assessed by another healthcare professional and was found to be 84% on room air. This patient required immediate medical attention and eventually required high-flow oxygen therapy.
The patient who required endotracheal intubation did not display signs or symptoms of hypoxemia or severe COVID-19 during a telehealth visit, but rapidly decompensated and was in respiratory distress upon arrival in the ED.
Each of these three patients had been at an increased risk for severe COVID-19, had silent hypoxemia, and required immediate supplemental oxygen. Each could have benefited from a pulse oximeter to monitor cardiopulmonary function and detect any deterioration sooner.
Patient safety and advocacy are core responsibilities of nursing. Based on current data and knowledge of severe COVID-19 and/or silent hypoxemia, high-risk patients with COVID-19 could benefit from the use of pulse oximetry at home. Some barriers to the care of patients with COVID-19 via telehealth can be addressed by educating patients about the home use of a pulse oximeter. The information obtained from the technology, in combination with other elements of patient assessment, helps telehealth nurses and providers determine a patient's level of risk and intervene appropriately.5,6
1. Centers for Disease Control and Prevention. What to do if you are sick. 2020. www.cdc.gov/coronavirus/2019-ncov/if-you-are-sick/steps-when-sick.html
2. Friedman J, Calderón-Villarreal A, Bojorquez L, Hernández CV, Schriger DL, Hirashima ET. Excess out-of-hospital mortality and declining oxygen saturation: the sentinel role of EMS data in the COVID-19 crisis in Tijuana, Mexico. medRxiv
. Preprint. 2020.
3. Bennett J, Munavvar M, Walker P, Phillips G. Respiratory advice for the non-respiratory physician in the time of COVID-19. Clin Med (Lond)
4. Theodore AC. Measures of oxygenation and mechanisms of hypoxemia. UpToDate. 2020.www.uptodate.com
5. Nicola M, O'Neill N, Sohrabi C, Khan M, Agha M, Agha R. Evidence based management guideline for the COVID-19 pandemic—review article. Int J Surg
7. Kim AY, Gandhi RT. Coronavirus disease 2019 (COVID-19): management in hospitalized adults. UpToDate. 2020. www.uptodate.com
8. McCreary EK, Angus DC. Efficacy of remdesivir in COVID-19. JAMA