Progress on Remote Respiratory Monitoring

Kaitlyn Hui—McMaster University Health Sciences 2022

With the onset of the COVID-19 pandemic, the need for remote respiratory monitoring has been integral for patients and physicians alike. This system allows for the continuous tracking of patient oxygen levels even when the clinician is not present, reducing the risk of missed respiratory complications. This is not only advantageous for patient safety since clinical staff can be quickly informed of adverse events through pager alarms, but allows physicians to care for multiple patients simultaneously. What may be surprising is that remote respiratory monitoring isn’t new to the scientific community: those with diabetes, heart disease, and lung disease have used remote devices to detect changes in their health for years. 

Respiratory rate has been shown to be a reliable gauge for COVID-19 patient respiratory deterioration as higher rates correlate with ICU admission and mortality.¹ Despite this finding, manually calculating these rates proves difficult and cannot be accurately determined through remote teleconferences, which have spiked in popularity given the shift to online consultations.¹ As well, patients often have trouble distinguishing their own breathing levels as the measure is self-reported through questions such as, “Is your breathing faster, slower, or the same as normal?”.² As laypeople often do not possess strong medical background knowledge, these types of questions are typically discouraged and are only used when necessary.² 

With the emergence of the COVID-19 Omicron variant, the urgency for remote monitoring has become even more pressing. In accordance with their national role, the Food and Drug Administration has even authorized numerous non-invasive remote and wearable monitoring devices to limit healthcare worker exposure to the virus.³ Although ambiguity remains regarding effectiveness and funding, remote sensors are being developed to obtain accurate respiratory rates such as the “Lab-on-Mask” (LOM) and other technological solutions. 

Recently, the LOM has been manufactured, embedded with a noncontact, multiplexed (can transmit several signals simultaneously) sensor system that can track patient vitals such as heart rate, blood pressure etc., while simultaneously measuring the mask’s interior temperature, all in real-time.⁴ Made from polydimethylsiloxane, a material used for flexible electronics, and other comfortable fabrics, the mask allows physicians to obtain stable signal output using signal-receiving sensors, data processing modules, and Bluetooth data.⁴ The photoplethysmography sensor, photodetector, and preamplifier can detect blood-oxygen (O₂) saturation levels through vasoconstriction or vasodilation. This is useful because O₂levels can identify respiratory infections such as COVID-19.⁴ This LOM can be handy in hospital settings to monitor infectious patients that are still allowed to wear a mask, which also limits spread.

There are also several other technological ways to remotely determine a patient’s vitals such as built-in cameras or microphones to recognize respiratory-induced chest wall movements and breathing sounds, respectively.¹ However, for patients that require long-term care, these solutions are not recommended purely because of the large amount of data that needs to be processed.¹In these cases, pressure sensors installed underneath mattresses, seating areas or backrests have proven to be low-cost with high accuracy, thus are more suitable for these populations.¹ As well, the use of radio waves is currently being explored as another possible avenue since respiratory rates can be transmitted through signal modulation, eliminating the need for troublesome body sensors altogether.¹ On the other hand, if one does wish to pursue that route, then there are “smart” devices such as chest straps that can measure changes in chest wall circumference, though they are much more expensive.¹ 

Luckily for us, in this modern age, medical advancements are shifting the healthcare landscape, allowing us to closely keep an eye out for patients in a safe and supportive manner. While this topic has been gaining traction given the significance of COVID-19, there are still many barriers regarding costs and efficacy. It is clear that this still remains a subject of interest, but we have a ways to go before developing a highly effective solution. Through recent developments, researchers are certainly moving towards the right direction in creating a future where remote respiratory monitoring can become a ubiquitous and cost-effective health technology used globally.

References

1. Massaroni C, Nicolò A, Schena E, Sacchetti M. Remote respiratory monitoring in the time of COVID-19 [Internet]. Frontiers in physiology. Frontiers Media S.A.; 2020 [cited 2021Nov27]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7274133/ 

2. Greenhalgh T, Koh GCH, Car J. Covid-19: A remote assessment in primary care [Internet]. The BMJ. British Medical Journal Publishing Group; 2020 [cited 2021Nov27]. Available from: https://www.bmj.com/content/368/bmj.m1182.long 

3. Center for Devices and Radiological Health. Covid-19 remote monitoring devices [Internet]. U.S. Food and Drug Administration. FDA; 2020 [cited 2021Nov27]. Available from: 

https://www.fda.gov/regulatory-information/search-fda-guidance-documents/enforcem ent-policy-non-invasive-remote-monitoring-devices-used-support-patient-monitoring during 

4. Xian Jun Loh, Xiaodong Chen, Liang Pan, Cong Wang, Haoran Jin, Jie Li, et al. Lab-on-mask for remote respiratory monitoring [Internet]. ACS Publications. 2020 [cited 2021Nov27]. Available from: https://pubs.acs.org/doi/10.1021/acsmaterialslett.0c00299