Accuracy of the Welch Allyn ConnexSpot Monitor in Measuring Respiratory Rate in the Emergency Department

Evaluation of the Welch Allyn Connex Spot Monitor in Measuring Respiratory Rate in the Emergency Department: a Prospective Observational Study Protocol

This prospective observational study will evaluate the accuracy of the Welch Allyn Connex Spot Monitor equipped with a Masimo SpO₂ finger sensor in measuring respiratory rate in the emergency department. Respiratory rate is a key predictor of patient deterioration, yet it is frequently measured inaccurately when assessed manually. In this study, respiratory rate values obtained by the monitor will be compared against manual counts performed by trained observers (physicians). An additional analysis will compare respiratory rates measured by trained observers with those recorded by triage nurses during triage. A subgroup analysis will also investigate whether cardiac arrhythmias influence measurement accuracy.

The aim is to examine if respiratory rates measured by the Welch Allyn Connex Spot Monitor are comparable to those obtained by trained observers and triage nurses in the emergency department.

Study Overview

• Status: Not yet recruiting
• Conditions: Respiratory Rate; Breathing Rate

Detailed Description

Design: prospective observational method comparison study

• Study Type: Observational
• Enrollment (Estimated): 170

Contacts and Locations

• Study Contact: Name: Bánk G Fenyves, MD, PhD; Phone Number: +3630016414; Email: fenyves.bank@semmelweis.hu
• Study Contact Backup: Name: Gabriella A Rapszky, MD; Phone Number: +36305742899; Email: rapszky.gabriella.anna@semmelweis.hu

Study Locations

• Hungary
  • Budapest, Hungary, 1082
    • Department of Emergency Medicine, Semmelweis University
    • Contact: Alexandra K Csapó; Phone Number: +36208250581; Email: csapo.alexandra.klaudia@semmelweis.hu
    • Sub-Investigator: Gabriella Anna Rapszky, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

The study will be conducted on patients admitted to the Emergency Department of Semmelweis University.

Description

Inclusion Criteria:

- all patients aged ≥18 years.

Exclusion Criteria:

• patients receiving invasive or non-invasive respiratory support;
• patients with disorders causing involuntary movements;
• skin or digit abnormalities preventing proper application of the pulse oximeter;
• clinically unstable patients on arrival (requiring immediate transfer to the resuscitation area);
• patients with a left ventricular assist device (LVAD).

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Agreement between respiratory rate values measured by the Welch Allyn Connex Spot Monitor and manual counts performed by trained observers (reference standard)	Respiratory rate will be measured simultaneously using the Welch Allyn Connex Spot Monitor and by trained observers performing manual counting over 60 seconds. Agreement between the two methods will be assessed using the Intraclass Correlation Coefficient and Bland-Altman analysis to evaluate bias and limits of agreement.	During the emergency department visit (single measurement per participant).

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Agreement between respiratory rate values measured by trained observers and those recorded by triage nurses during triage	Respiratory rate measurements recorded by triage nurses during triage will be compared with manual 60-second counts performed by trained observers. Agreement between the two methods will be evaluated using the Intraclass Correlation Coefficient and Bland-Altman analysis to assess bias and limits of agreement.	During the emergency department visit (single measurement per participant).
Agreement between respiratory rate values measured by the Welch Allyn Connex Spot Monitor and manual counts performed by trained observers in patients with ECG-confirmed arrhytmias	Respiratory rate measurements recorded by triage nurses during triage will be compared with manual 60-second spot measurements performed by trained observers. Agreement between the two methods will be evaluated using the Intraclass Correlation Coefficient and Bland-Altman analysis to assess bias and limits of agreement.	During the emergency department visit (single measurement per participant).

Collaborators and Investigators

• Sponsor: Dr. Rapszky Gabriella Anna
• Collaborators: Semmelweis University

Publications and helpful links

General Publications

• Goldhill DR, White SA, Sumner A. Physiological values and procedures in the 24 h before ICU admission from the ward. Anaesthesia. 1999 Jun;54(6):529-34. doi: 10.1046/j.1365-2044.1999.00837.x.
• Edmonds ZV, Mower WR, Lovato LM, Lomeli R. The reliability of vital sign measurements. Ann Emerg Med. 2002 Mar;39(3):233-7. doi: 10.1067/mem.2002.122017.
• Goldhill DR, McNarry AF, Mandersloot G, McGinley A. A physiologically-based early warning score for ward patients: the association between score and outcome. Anaesthesia. 2005 Jun;60(6):547-53. doi: 10.1111/j.1365-2044.2005.04186.x.
• Churpek MM, Yuen TC, Park SY, Meltzer DO, Hall JB, Edelson DP. Derivation of a cardiac arrest prediction model using ward vital signs*. Crit Care Med. 2012 Jul;40(7):2102-8. doi: 10.1097/CCM.0b013e318250aa5a.
• Semler MW, Stover DG, Copland AP, Hong G, Johnson MJ, Kriss MS, Otepka H, Wang L, Christman BW, Rice TW. Flash mob research: a single-day, multicenter, resident-directed study of respiratory rate. Chest. 2013 Jun;143(6):1740-1744. doi: 10.1378/chest.12-1837.
• Loots FJ, Dekker I, Wang RC, van Zanten AR, Hopstaken RM, Verheij TJ, Giesen P, Smits M. The accuracy and feasibility of respiratory rate measurements in acutely ill adult patients by GPs: a mixed-methods study. BJGP Open. 2022 Dec 20;6(4):BJGPO.2022.0029. doi: 10.3399/BJGPO.2022.0029. Print 2022 Dec.
• 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 hospitalised adults. BMJ Qual Saf. 2017 Oct;26(10):832-836. doi: 10.1136/bmjqs-2017-006671. Epub 2017 Jun 26.
• Leuvan CH, Mitchell I. Missed opportunities? An observational study of vital sign measurements. Crit Care Resusc. 2008 Jun;10(2):111-15.
• Mochizuki K, Shintani R, Mori K, Sato T, Sakaguchi O, Takeshige K, Nitta K, Imamura H. Importance of respiratory rate for the prediction of clinical deterioration after emergency department discharge: a single-center, case-control study. Acute Med Surg. 2016 Nov 10;4(2):172-178. doi: 10.1002/ams2.252. eCollection 2017 Apr.

Helpful Links

• Product page for the Welch Allyn Connex Spot Monitor

Study record dates

Study Major Dates

• Study Start (Estimated): December 1, 2025
• Primary Completion (Estimated): January 1, 2026
• Study Completion (Estimated): February 1, 2026

Study Registration Dates

• First Submitted: December 10, 2025
• First Submitted That Met QC Criteria: December 10, 2025
• First Posted (Actual): December 23, 2025

Study Record Updates

• Last Update Posted (Actual): December 23, 2025
• Last Update Submitted That Met QC Criteria: December 10, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Keywords: emergency department; respiratory rate; Welch
• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Pathological Conditions, Signs and Symptoms; Emergencies
• Other Study ID Numbers: SOK-LEGZ25

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No