Red Lights and Sirens:
Do We Need Them?
Michael D. Curtis, MD, FACEP
EMS Medical Director
Saint Michael’s Hospital – Stevens Point
Saint Clare’s Hospital – Weston
Objectives
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Define the problems related to using red
lights and sirens in EMS
State the conclusions of research on the
value of red lights and sirens in EMS
Develop an understanding of the
conceptual framework for balance in the
use of RL&S in EMS
Discuss steps industry leaders can take to
reduce the toll on our industry
Perspective
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Primum Non Nocere – Above all, do no
harm!
Origins of RL&S Transport
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“Back in the day” when ambulances were
merely transport vehicles and few if any
interventions were performed in the field
A practice adopted from law enforcement and
fire services without question as to safety and
efficacy
Perspective
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The Culture of RL&S in EMS
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"...loose interpretation of what constitutes an
emergency has essentially given [EMV
operators permission] to operate their
vehicles as they see fit while carrying victims
who are essentially stable by anyone's
definition."

Paul S. Auerbach, MD, et al
JAMA 1987;258:1487Ð1490
Excerpted from: Prehospital and Disaster Medicine, April-June 1994
My Perspective
Like so many therapeutic interventions
throughout the history of medicine that
have landed on the scrapheap of good
intentions, the widespread use of red lights
and sirens in EMS should be abandoned,
their use being restricted to the very few
cases in which the potential benefits may
outweigh the associated risks – for they
have largely proven to be
‘not helpful and potentially harmful’ .
Characteristics of
Fatal Ambulance Crashes
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Kahn, Pirrallo & Kuhn
US NHTSA FARS
1987-1997
339 Ambulance crashes
405 fatalities & 838 other injuries
Emergency Mode of Travel (RL&S)
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60% (202/339) of all crashes
58% (233/405) of all fatalities
Prehospital Emergency Care 2001; 5:261-269
Characteristics of
Fatal Ambulance Crashes
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Kahn, Pirrallo & Kuhn
In most fatal ambulance crashes:
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Traveling in the “emergency mode” (RL&S)
The ambulance is the striking vehicle
The crash occurs at an intersection
Occupants of other vehicles are more likely to die or
suffer serious injury than occupants of the ambulance
Rear compartment occupants are more likely to be
injured or die than front compartment occupants
The ambulance drives have poor driving histories
Prehospital Emergency Care 2001; 5:261-269
Ambulance Crash Injuries Among
US EMS Workers 1991-2002
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Based on NHTSA FARS data
300 Fatal Ambulance Crashes
82 deaths in the ambulances
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27 EMS workers
Most EMS worker deaths in front
compartment
Lack of restraint use cited in many of the EMS
worker deaths
275 deaths of others (in vehicles or
pedestrians)
MMWR 2003; 58:154-156
Occupational Fatalities in EMS:
A Hidden Crisis
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Maguire & Hunting, et al
Death rate among EMS workers 12.7 per
100,000 workers
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More than twice the National Average (5.0)
14.2 per 100,000 for Police
16.5 per 100,000 for Firefighters
Highest risk occurs in transportation
related incidents
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9.6 per 100,000 EMS workers
Ann Emerg Med. 2002;40:625-632
Legal Risks
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Colwell & Pons, et al
Claims Against a Paramedic Ambulance
Service: A Ten-Year Experience
Denver: 1984 – 1993
82 Claims against the EMS Agency
11 Lawsuits
J Emerg Med 1999; 17(6):999-1002
Legal Risks
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Colwell & Pons, et al
Frequency of Named Parties (N=82):
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100% Paramedics involved
46% The City of Denver
20% The Department of Health and Hospitals
4% The Physician Medical Director
J Emerg Med 1999; 17(6):999-1002
Legal Risks
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Colwell & Pons, et al
59 of 82 (72%) ambulance crashes
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6 lawsuits
Run status not known in 10 runs
29/49 (59%) emergency use (RL&S)
5/49 (10%) non-emergency use
20/49 (31%) not on a call
J Emerg Med 1999; 17(6):999-1002
Legal Risks
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Colwell & Pons, et al
6 Lawsuits went to trial
5/6 (83%) due to ambulance crashes
36/59 (61%) property damage claims
23/59 (39%) personal injury claims
Rate: 1 claim per 5,084 patient transport
runs (0.197 claims per 1,000)
J Emerg Med 1999; 17(6):999-1002
Legal Risks
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Colwell & Pons, et al
Total payout: $579,956
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Max per claim: $150,000 (Gov’t Immunity)
Three lawsuits from ambulance crashes
with personal injury paid out:
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$32,000
$100,000
$150,000
J Emerg Med 1999; 17(6):999-1002
Costs
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In excess of $500 Million Annually*
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“A conservative estimate”
“Could be 10 times or more higher”
Nadine Levick, MD, MPH
 Personal Conversation
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* http://www.objectivesafety.net/LevickAAAM2005.pdf
Code 3 vs. Code 2 Studies
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Hunt & Brown, et al
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Small Urban Setting – Transport Phase
Annals of Emergency Medicine 1995;25:507-511
RL&S transport time savings average 43.5 sec vs. without RL&S
(N=50)
RL&S transport not warranted, except in rare circumstances
Brown & Whitney, et al
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Medium Size Urban Setting – Response Phase
Prehospital Emergency Care 2000;4:70-74
RL&S Response time savings average 1 min 46 sec
Statistically significant
Clinically relevant in very few circumstances
Code 3 vs. Code 2 Studies
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Ho & Casey
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Major Urban Setting – Response Phase (N=64)
Annals of Emergency Medicine 1998;32:585-588
Average time savings 3.02 minutes (38.5%)
Statistically significant
Ho & Lindquist
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Rural Setting – Response Phase (N=67)
Prehospital Emergency Care 2001;5:159–162
Average time savings 3.63 min (30.9%)
Statistically significant
The Effectiveness of Lights and
Sirens During Paramedic Transport
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O’Brien, Price & Adams
Prospective case-control observational
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Simultaneous Code 3 ambulance transport vs.
Non-Code 3 observer vehicle (OV)
Convenience sample of 75 runs
Do RL&S save time?
Does the time savings result in clinically
significant interventions at the destination
hospital?
Prehospital Emergency Care 1999; 3:127-130
The Effectiveness of Lights and
Sirens During Paramedic Transport
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O’Brien, Price & Adams
Setting:
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University of Louisville School of Medicine
Jefferson County Kentucky
365 square miles
Annual run volume: 36,000
Suburban single-tier third service
Ambulance makes Code 3 transport decision
Observer vehicle follows but obeys all traffic laws
Prehospital Emergency Care 1999; 3:127-130
The Effectiveness of Lights and
Sirens During Paramedic Transport
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O’Brien, Price & Adams
Ambulance vs. OV
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Mean Ambulance transit time 666 sec (11:6)
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Mean OV transit time 896 sec (14:56)
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SD 203 sec
SD 269 sec
Mean Difference 230 sec (3:50)
SD 126 sec (Range 23 sec to 13 min, 3 sec)
 Statistically significant (p<0.0005)
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Prehospital Emergency Care 1999; 3:127-130
The Effectiveness of Lights and
Sirens During Paramedic Transport
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O’Brien, Price & Adams
Ambulance vs. OV
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Average distance traveled was 8.8 miles
Statistically significant correlations between
the transit time difference and:
Number of stop lights
 Traffic intensity
 Distance traveled
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No differences based on the time of day
Prehospital Emergency Care 1999; 3:127-130
The Effectiveness of Lights and
Sirens During Paramedic Transport
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O’Brien, Price & Adams
Hospital Interventions
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81% (61/75) received none
5% (4/14) received critical interventions that could
not be accomplished by the paramedics before
hospital arrival
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Re-intubation
One being prepped for intubation
IV + D50 for a hypoglycemic after failed IV in the field
Diazepam for child in status epilepticus - difficult to start IV
Remaining interventions felt to be non-critical
Prehospital Emergency Care 1999; 3:127-130
The Effectiveness of Lights and
Sirens During Paramedic Transport
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O’Brien, Price & Adams
Conclusions
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There was a statistically significant time savings with
RL&S transport
The use of RL&S added little to the care of those
patients who received successful interventions by
paramedics in the field
Few clinically relevant interventions were
accomplished at the hospital during the time saved by
RL&S transport
Paramedic ALS interventions significantly reduce the
need for RL&S transport
Prehospital Emergency Care 1999; 3:127-130
A Question of Balance
System
Performance
Goals:
Response Time
Safety:
The Provider’s
The Patient’s
The Public’s
Public
Expectations:
“When it’s my
emergency!”
The needs of the
patient
A Question of Balance
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Number Needed to Treat (NNT)
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The number needed to treat a specific disease
with a given therapy in order to prevent one
additional death
The inverse of the ‘risk difference’ between
alternative therapies
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The absolute change in risk due to the intervention
Related to the characteristics of the disease
and the characteristics of the treatment
A Question of Balance
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Number Needed to Harm (NNH)
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The number of times a specific therapy is
given before it causes an adverse outcome
The inverse of the ‘risk difference’ between
alternative therapies
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The absolute change in risk due to the intervention
Related to the characteristics of the treatment
alone
A Question of Balance
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Number Needed to Treat vs. Harm
Example: Fibrinolytics for AMI vs. Placebo
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3% absolute risk reduction of death from AMI
1% absolute risk increase of fatal intracranial
hemorrhage
NNT = 1÷ 3% = 33
NNH = 1÷ 1% = 100
Thus, for every 3 lives we save with lytics,
one life will be lost
A Question of Balance
NNT vs. NNH Across the Spectrum of Prehospital
Emergencies
NNT & NNH
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Number Needed to Treat
Number Needed to Harm
Likelihood of RL&S to Reduce
Avoidable Adverse Patient Outcomes
A Question of Balance
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Consider this…
If an ambulance crashes while responding
to a call, and no harm comes to the
patient for whom it was summoned as a
result of the ensuing delay, then the
consequences of the crash were realized
for no gain.
A Question of Balance
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Consider this…
If I am correct in believing that RL&S are
generally ‘not helpful and potentially
harmful’, then it would seem reasonable to
limit their use to the few situations in which
the potential benefits outweigh the potential
harm, and if that is not clearly known, then
the laws of probability favor not using them,
until better information becomes available.
A Question of Balance
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Consider this…
If I am correct in believing that RL&S is
‘generally not helpful and potentially
harmful’, then it would seem reasonable to
conclude that the premise of improved
emergency vehicle driver education is at
best a double-edged sword.
NAEMSP Position Statement
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Few published data on effectiveness of RL&S in
reducing response [or transport] times
RL&S should be reserved for situations in which
patient welfare is at stake
RL&S during response and transport should be
based on situational and patient problem
assessments and the Medical Director should
participate in the development of related policies
Crashes should be evaluated by EMS system
managers and medical directors
Prehospital and Disaster Medicine, April-June 1994
NAEMSP Position Statement
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EMS dispatch should use a priority reference
system to identify which calls warrant RL&S
Except for suspected life-threatening, timecritical cases or cases involving multiple patients,
RL&S response by more than one EMV usually is
unnecessary
The utilization of emergency RL&S should be
limited to emergency response and emergency
transport situations only
Prehospital and Disaster Medicine, April-June 1994
NAEMSP Position Statement
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All agencies should institute and maintain
emergency vehicle operation education
programs for vehicle operators
Scientific studies evaluating the effectiveness of
RL&S under specific situations should be
conducted and validated
Laws and statutes should take into account
prudent safety practices by both EMS providers
and the monitoring public
Prehospital and Disaster Medicine, April-June 1994
Thought Provoking?
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Should we – the leaders of the EMS industry –
seek legislative reforms to regulate the
appropriate use of RL&S?
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Stopping at red lights
Driver training and certification
Driver background checks
Technological innovations to promote safety
Priority Medical Dispatching
Written policies for emergency medical vehicle
operations
Others?
Thought Provoking?
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Even if we master and solve this problem,
our work will not be done
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The issue of safety in our industry goes well
beyond the issue of RL&S
We also need to master the issues of
occupational safety and health among EMS
workers
We also need to master the design
specifications of ambulances as they pertain to
the safety of the EMS work environment
A ‘Must See’ Presentation

Dr. Nadine Levick
 Wisconsin Division of the American Trauma
Society

2007 William H. Perloff Trauma Care
Conference: Reality Trauma
November 9-10
 Holiday Inn – Stevens Point
 For further information or to receive the application,
contact Lynne Sears at lsears@uwhealth.org,
608-265-0372 or the WATS website at
www.wats.cehss.org.

Questions?
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Thank You!
Contact Information:
Michael D. Curtis, MD, FACEP
EMS Medical Director
Saint Michael’s Hospital – Stevens Point
Saint Clare’s Hospital – Weston
mike.curtis@ministryhealth.org