Prehospital and Disaster Medicine

Original Research

Medical Priority Dispatch System Breathing Problems Protocol Key Question Combinations are Associated with Patient Acuity

Jeff Clawsona1 c1, Tracey Barrona2, Greg Scotta1, A. Niroshan Siriwardenaa3, Brett Pattersona1 and Christopher Ololaa1

a1 International Academies of Emergency Dispatch (IAED), Salt Lake City, Utah USA

a2 International Academies of Emergency Dispatch (IAED), Bristol, UK

a3 East Midlands Ambulance Service NHS Trust, Nottingham and University of Lincoln, Lincoln, UK


Introduction The Breathing Problems Chief Complaint (CC) protocol in the Medical Priority Dispatch System (MPDS) was the system's most frequently used protocol. While “severe breathing problems” is a significant predictor of cardiac arrest (CA), previous data have demonstrated that the DELTA-level determinant codes in this CC contain patients across a wide spectrum of acuity.

Hypothesis The hypothesis in this study was that certain combinations of caller answers to the breathing problems protocol key questions (KQs) are correlated with different but specific patient acuities.

Methods This was a retrospective study conducted at one International Academies of Emergency Dispatch (IAED) Accredited Center of Excellence. Key Question combinations were generated and analyzed from 11 months of dispatch data, and extracted from MPDS software and the computer assisted dispatch system. Descriptive statistics were used to evaluate measures between study groups.

Results Forty-two thousand cases were recorded; 52% of patients were female and the median age was 61 years. Overall, based on the original MPDS Protocol (before generating KQ combinations), patients with abnormal breathing and clammy conditions were the youngest. The MPDS DELTA-level constituted the highest percentage of cases (74.0%) and the difficulty speaking between breaths (DSBB) condition was the most prevalent (50.3%). Ineffective breathing and not alert conditions had the highest cardiac arrest quotient (CAQ). Based on the KQ combinations, the CA patients who also had the not alert condition were significantly older than other patients. The percentage of CA outcomes in asthmatic patients was significantly higher in DSBB plus not alert; DSBB plus not alert plus changing color; and DSBB plus not alert plus clammy conditions cases, compared to asthmatic abnormal breathing cases.

Conclusions The study findings demonstrated that MPDS KQ answer combinations relate to patient acuity. Cardiac arrest patients are significantly less likely to be asthmatic than those without CA, and vice versa. Using a prioritization scheme that accounts for the presence of either single or multiple signs and/or symptom combinations for the Breathing Problems CC protocol would be a more accurate method of assigning DELTA-level cases in the MPDS.

Clawson J, Barron T, Scott G, Siriwardena AN, Patterson B, Olola C. Medical Priority Dispatch System breathing problems protocol key question combinations are associated with patient acuity. Prehosp Disaster Med. 2012;27(4):1-6.

(Received January 04 2012)

(Accepted April 13 2012)

(Revised April 25 2012)

(Online publication July 24 2012)


c1 Correspondence: Tracey Barron, BSc International Academies of Emergency Dispatch – UK Suite 7a, Froomsgate House, Rupert Street Bristol, BS1 2QJ UK E-mail


Conflicts of interest and funding: JC is the inventor of the MPDS studied herein and the Chief Executive Officer (CEO)/Medical Director of Priority Dispatch Corporation. TB, GS, BP and CO are employees of the IAED. NS is an employee of East Midlands Ambulance Service, UK. No specific funding was provided outside of the employment relation.