Stakes Are High

Audrey Fraizer

Audrey Fraizer

Best Practices

FirstWatch Founder and President Todd Stout and webinar panelists lauded a joint position statement on the use of Lights-and-siren (L&S) issued Feb. 14, 2022, in conjunction with a National EMS Quality Alliance (NEMSQA) quality improvement partnership project. The statement does not eliminate or dismiss the use of L&S. Rather, sponsoring organizations believe that certain principles (included in the statement) should guide L&S use during emergency vehicle response to medical calls and initiatives to optimize the use of L&S when appropriate.  

“We’re not here to throw the baby out with the bath water,” said panelist Bryan Wilson, EMS Medical Director, City of Bethlehem EMS, Pennsylvania (USA), and Emergency and EMS Physician at St. Luke’s University Health Network (Bethlehem, Pennsylvania). “We’re here to improve what we can.”  

During the webinar (March 24, 2022), panelists presented data supporting principles the statement highlights, including call categorization to identify subsets of calls based upon response resources needed and medical urgency of the call, medical director oversight, quality assurance, and public education.  

Wilson highlighted a study, “Use of Emergency Warning Devices During EMS Transport to the Hospital,” which garnered a National Association of EMS Physicians (NAEMSP) research award at the 2020 annual meeting.1 According to the study’s findings: 

  • A large amount of misinformation exists in the use of L&S. 
  • Crews are very willing to limit use when risks become clear and no harm is seen. 
  • Crews should be allowed to make the choice based on available information and teaching policy. 
  • By focusing on L&S in transport, the use of L&S in response also decreased. 

From a Canadian perspective, most municipalities require reporting response time and outcome data in the Niagara Region, and the data informs response plans, said Niagara (Ontario, Canada) EMS Deputy Chief Rick Ferron.   

In 2019, Niagara EMS significantly revised policies for L&S use, limiting their use to responses where they are required on critical responses only. These time-sensitive emergencies, which account for less than 10% of all EMS responses in Niagara, are identified by using medical call prioritization system dispatch determinant descriptors from the Medical Priority Dispatch System (MPDS®).2  

In this way, the appropriate level of response is coordinated to the necessary emergency resources, according to a statement released by Niagara EMS, medical call prioritization combined with an evidence-based Clinical Response Plan.3  

“The stakes are high,” Ferron said. “Last thing we want to do is send a last resource lights-and-siren, leaving us no other resources to send.” 

Nicola “Nikki” Little, Quality and Patient Safety Officer, Winnipeg Fire Paramedic Service, Manitoba (Canada), introduced the National EMS Quality Alliance Improvement Project methodology to reduce L&S through collecting and analyzing key performance and quality indicators. Little recommended formulating a plan based on what it is the agency wants to accomplish and determining how to know that the change will result in improvement. 

“Understand your system; look at the urban legends,” she said. “Test change ideas. Learn. Adapt. Adopt. Abandon whatever doesn’t help you to accomplish your goals.” 

Winnipeg Fire Paramedic Service set a goal to reduce L&S responses by 50% and L&S transports by 5%, by March 24, 2023. 

L&S phenomenon

Ambulances were the first emergency vehicles fitted with lights, but they were initially placed inside the patient compartment to shine a light on patient care for medics during transport. Lights eventually moved outside to alert the driving public. “This is an emergency; clear the path!” Electric sirens coupled to the lights replaced bells and gongs.  

L&S evolved into a cultural phenomenon. Lights-and-siren distinguished ambulances, police cars, and fire trucks from civilian vehicles on the roads. They remained an effective solution when civilians, law enforcement, and emergency personnel traded horseless carriages for motorized vehicles.  

Things changed. Evidence brought debate. There is a time and place for L&S, but they could also exacerbate an emergency despite good intentions. Research shows their use in every emergency response is not necessary and dangerous to the public and responders. For example:  

Ambulance use of L&S is associated with increased risk of ambulance crashes, and the association is greatest during the transport phase, according to a study using the 2016 National EMS Information System data set to identify 911 scene responses and subsequent patient transports by transport-capable emergency medical services (EMS) units.4  

According to related statistics: 

  • On average, 29 fatal crashes occur each year involving ambulances with a yearly average of 33 fatalities.5 When examining the fatalities, “25% of fatalities are inside the ambulance, with the other 75% most often being the driver or passenger of the vehicle which struck or was struck by an ambulance.”6 
  • When an ambulance responds to an emergency call without using lights-and-siren, the crash rate is 4.6 per 100,000 responses. The crash rate increases to 5.5 when lights-and-siren are used. The increase in risk is even greater when the ambulance is transporting a patient. The crash risk without lights-and-siren is 7.0 per 100,000 transports and increases to 16.5 per 100,000 transports when lights-and-siren are used throughout the transport.7

“We’re evolving in time for the better care of ourselves and patients,” Stout said. “It’s about organizational behavior and how an organization adapts.”  

For the most part, responders and the public have not been quick to adapt to changes, according to webinar panelists. L&S notify the public of an emergency vehicle in the roadway. Their use is part of insurance and contract requirements. The long-held belief is that L&S equate to time savings and, consequently, save more lives.   

To the contrary, however, “Response time alone does not save lives,” said panelist Douglas Kupas, M.D., Commonwealth EMS Director for the Bureau of Emergency Medical Services for the Pennsylvania (USA) Department of Health (PaDOH). “It’s about interventions, not time. It’s about the quality of service provided to our patients.”  

Stout concluded the webinar advocating the positioning of the “Joint Statement on Lights & Siren Vehicle Operations on Emergency Medical Services Responses” and showcasing results of L&S use optimization projects. “Inspire others to know that you’re actually making these beneficial changes. You are doing absolutely fascinating work.” 

Jeff Clawson, M.D., Medical Director of the International Academies of Emergency Dispatch® (IAED) Research, Standards, and Academics Division and inventor of the MPDS® Protocols, has been a longtime proponent of measured, medically approved, preplanned responses “based on the IAED’s process in protocol to identify which emergency calls require the use of lights-and-siren and those that don’t, in addition to local discretion to develop policy reflecting our recommendations.”8 

The joint statement is published in the Annals of Emergency Dispatch & Response (AEDR), published by the IAED and posted on the AEDR website (https://www.aedrjournal.org/joint-statement-on-lights-siren-vehicle-operations-on-emergency-medical-services-responses). The IAED is among the 14 EMS sponsoring organizations.   



1 “Use of Warning Lights and Siren in Emergency Medical Vehicle Response and Patient Transport.” Prehospital and Disaster Medicine. 2012; June 28. https://www.cambridge.org/core/journals/prehospital-and-disaster-medicine/article/abs/use-of-warning-lights-and-siren-in-emergency-medical-vehicle-response-and-patient-transport/992FA3DCA4BEBEDF366A010DF600F260 (accessed March 28, 2022).

2 “Niagara EMS leading in international policy on the use of lights and siren.” https://www.iheartradio.ca/610cktb/news/niagara-ems-leading-group-on-use-of-sirens-and-lights-1.17278186  (accessed March 28, 2022).  

3 See note 2.  

4 Watanabe B, Patterson G, Kempema J, Magallanes O, Brown L. “Is Use of Warning Lights and Sirens Associated With Increased Risk of Ambulance Crashes? A Contemporary Analysis Using National EMS Information System (NEMSIS) Data.” Annals of Emergency Medicine. 2018; July. https://pubmed.ncbi.nlm.nih.gov/30648537/#:~:text=Results%3A%20Among%2019%20million%20included,%25%20CI%201.2%20to%201.9 (accessed March 28, 2022).  

5 Smith N. “A National Perspective on Ambulance Crashes and Safety.” EMS World. 2015; September. https://www.ems.gov/pdf/emsworldambulancecrasharticlessept2015.pdf (accessed March 19, 2022). 

6 See note 2. 

7 National Safety Council. “Road Users.” 2021. https://injuryfacts.nsc.org/motor-vehicle/road-users/emergency-vehicles/ (accessed March 29, 2022). 

8 Clawson, J. “Lights-and-siren hazards.” Journal of Emergency Dispatch. 2017; April 12. https://www.iaedjournal.org/lights-siren-hazards (accessed March 28, 2022).