The best predictor of patient decline is the least measured vital sign

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BioButton Wearable Device in use by healthcare professionals, in office and hospital settings, with patients.

Did you know respiratory rate is one of the two most reliable early indicators for detecting deterioration in low-acuity patients?1

And are you aware that manual methods of assessing and documenting respiratory rate are not a dependable measurement for predicting potential complications in patients?

Yet, manual measurement continues to be the most common way of capturing a patient’s respiratory rate — as an important vital sign — in non-critical areas of care today. Even though manual collection makes accurate and consistent respiratory rate reporting a challenge.

Considering the importance of reliable respiratory rate monitoring and the difficulties care providers face when it comes to manually collecting respiratory rate, clinicians need a standardized approach for measuring and recording this important vital sign.

Read more to find out how technology can support the collection and documentation of respiratory rate measurements to help make respiratory monitoring more precise — so you can use it as a true early indicator of patient deterioration.


5 limitations of manual respiratory rate measurement

Capturing an early indication of respiratory rate increases may help clinicians predict adverse patient events in hospital wards.  Among isolated vital signs, maximum respiratory rate is the most accurate predictor of in-hospital cardiac arrest.2

But manual respiratory collection practices may make it difficult to detect abnormal respiratory rates early enough when you consider the following:

  • Spot checking respiratory rate values at certain time intervals throughout the day only captures a momentary snapshot of a patient’s condition. 3,4
  • Manually measuring respiratory rate can be time-consuming and overwhelming.5
  • Respiratory rate is the most infrequently recorded vital sign, documented five times less frequently than blood pressure.6
  • There is a greater risk for human error with subjective capture of vital signs.3,4
  • Manually recorded respiratory rate may be inaccurately recorded with bias toward normal respiratory rate.7,8


Technology that can improve respiratory monitoring practices

Prioritizing respiratory monitoring as an important vital sign for early detection of patient deterioration begins with accurate assessment and consistent documentation. Respiratory rate monitoring tools can streamline both the collection and transmission of respiratory rate measurements.

Using medical-grade wearable devices like the BioButton®* multi-parameter wearablehelp provide continuous monitoring. Among other FDA-cleared parameters and additional biometrics, it includes automated monitoring of resting respiratory rate, which captures more accurate data than manual respiratory rate collection. The BioButton®* multi-parameter wearable can also provide trends of respiration rate over time.

Related: See how the BioButton® wearable captures true variability of respiratory rate.

Capnography promotes continuous monitoring of respiratory rate, too, by turning a subjective value into an objective value.

The key advantage of capturing respiratory rate with capnography monitoring devices like Microstream™ capnography is that it measures ventilation directly at the airway. Ventilation is the process of inhalation of oxygen from the atmosphere into the lungs, gas exchange occurring at the alveoli, resulting in carbon dioxide (CO2) gas, which is expelled during exhalation.

Continuous monitoring of CO2-derived respiratory rate and etCO2 can play an important role in helping detect life-threatening conditions.9 Capnography continuously delivers both of these values to clinicians in an accurate and objective manner.10-13

High correlation and clinical performance to capnography standards

Related: Explore how Microstream™ capnography monitoring supports clinicians in detecting respiratory complications early by continuously monitoring respiratory rate.

With Microstream™ capnography plus Nellcor™ pulse oximetry technology rolled into the new RespArray™ patient monitor, clinicians now have a continuous way to monitor changes in a patient’s respiratory status on the medical-surgical floor — to help detect respiratory compromise in its early stages.14,15

†The BioButton® multi-parameter wearable device is not intended for critical care monitoring.

Patient monitoring technologies should not be used as the sole basis for diagnosis or therapy and are intended only as adjuncts to patient assessment.

  1. Chaboyer W, Thalib L, Foster M, Ball C, Richards B. Predictors of adverse events in patients after discharge from the intensive care unit. Am J Crit Care. 2008;17(3):255–63
  2. Churpek MM, Yuen TC, Huber MT, Park SY, Hall JB, Edelson DP. Predicting cardiac arrest on the wards: a nested case-control study. Chest. 2012;141(5):1,170–1,176.
  3. Karlen W, Gan H, Chiu M, et al. Improving the accuracy and efficiency of respiratory rate measurements in children using mobile devices [published correction appears in PLoS One. 2015;10(2):e0118260]. PLoS One. 2014;9(6):e99266.
  4. Philip KE, Pack E, Cambiano V, Rollmann H, Weil S, O'Beirne J. The accuracy of respiratory rate assessment by doctors in a London teaching hospital: a cross-sectional study. J Clin Monit Comput. 2015;29(4):455–460.
  5. Mok, W et al. Attitudes towards vital signs monitoring in the detection of clinical deterioration: scale development and survey of ward nurses. Int J Qual Health Care (2015) 27 (3):207–213.
  6. Leuvan CH, Mitchell I. Missed opportunities? An observational study of vital sign measurements. Crit Care Resusc. 2008;10(2):111–115.
  7. Granholm A, Pedersen NE, Lippert A, Petersen LF, Rasmussen LS. Respiratory rates measured by a standardized clinical approach, ward staff, and a wireless device. Acta Anaesthesiol Scand. 2016;60(10):1444–1452.
  8. Badawy J, Nguyen OK, Clark C, Halm EA, Makam AN. Is everyone really breathing 20 times a minute? Assessing epidemiology and variation in recorded respiratory rate in hospitalized adults. BMJ Qual Saf. 2017;26(10):832–836.
  9. Microstream™ Sampling Lines Product Specification.
  10. Autet L, Frasca D, Pinsard M, Cancel A, Rousseau L, Debaene B, Mimoz O. Evaluation of acoustic respiration rate monitoring after extubation in intensive care unit patients. Br J Anaesth. 2014; (113):195–197.
  11. Frasca D, Geraud L, Charriere J M, Debaene B and Mimoz O. Comparison of acoustic and impedance methods with mask capnometry to assess respiration rate in obese patients recovering from general anaesthesia. Anaesthesia. 2015;(70):26–31.
  12. Bergese S D, Mestek M L, Kelley S D, McIntyre R Jr, Uribe A, Sethi R, et al. Addison PS. Multicenter study validating accuracy of a continuous respiratory rate measurement derived from pulse oximetry: a comparison with capnography. Anesth. Analg. 2017;124(4):1,153–1,159
  13. Ermer S, Brewer L, Kuck K, Orr J. Detecting low respiratory rates using myriad, low-cost sensors. Utah Space Grant Consortium; 2017.
  14. Maddox R, Williams CK, Oglesby H, et al. Clinical experience with patient-controlled analgesia using continuous respiratory monitoring and a smart infusion system. Am J Health Syst Pharm. 2006;63(2):157–164.
  15. Chung F, Wong J, Mestek ML, Niebel KH, Lichtenthal P. Characterization of respiratory compromise and the potential clinical utility of capnography in the post-anesthesia care unit: a blinded observational trial. J Clin Monit Comput. 2020;34(3):541–551.


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