Ambulance
Crew Configuration: Are Two Paramedics Better Than One?
By David Shotwell, JD, MICP, Mark A. Merlin, DO, EMT-P, FACEP and Vincent D. Robbins, FACPE, FACHE | 10.8.18
The appropriate
complement of ambulance crews has long been debated in the United States. From
the very beginning of modern day EMS, circa 1966, we’ve failed to agree on the
most efficacious number of crew members who should staff an ambulance, as well
as their appropriate combined scope of practice.1,2
Numerous models exist
around the country, differing in both the number of practitioners that compose
a crew, and the levels of training each possesses.3 Levels of EMS practitioners have been well-defined through
state regulations and national standards. Published reports have concluded the
essential nature of EMS, the improved patient outcomes which result from such
services and their positive economic impact upon our society. However, there’s
no consensus on the best complement of practitioners necessary for EMS systems
to function at an optimal level.4–8
Although most agree
that basic life Support (BLS) and advanced life support (ALS) services should
be available to every community and every patient, this isn’t necessarily the
case nationwide.3
Neither is the
organizational structure, design of the delivery systems for these two EMS
tiers, or how they interact with each other.9
Some communities
utilize all ALS ambulances in a single-tier system, sending these units to all
requests for EMS. Others use separate response ALS units (with partial, or all
ALS crews, which may or may not be vehicles with the ability to transport patients)
and BLS ambulances, dispatched together and converging on the scene to treat a
subpopulation of all EMS patients considered as the most seriously ill or
injured.
In these systems, BLS
ambulances are sent without ALS units on cases considered less serious or
non-life-threatening. Even other systems use first response, non-transport
units staffed with ALS practitioners and separate ambulances with ALS, or
partial ALS, crews.2–4
One standard that does
appear ubiquitous, is that it’s assumed a minimum of two crew members are
necessary to staff the EMS unit that transports a patient to definitive care.
This is the case regardless of the level of EMS provided or the individual crew
members’ individual scopes of practice; it’s based on the simple logic that during
transport to a hospital, one member would need to operate the vehicle, while
the other needs to attend the patient providing ongoing care.2 Little has been written regarding the need for more than
one provider to attend to serious or critical cases in the patient compartment.
It appears this will
remain the case for the foreseeable future, at least until technology permits
autonomously functioning ambulances to be operated without a human driver.
However, the optimal training or certification level, and the scope of
practice, for each of these two crew members has remained debatable.
However, when we focus
more specifically on the crew configuration for ALS services operating in a
multitiered EMS system, it’s not axiomatic that the crew needs to be staffed by
more than one person. And, when the ALS unit also transports the patient, so
that at least two crew members are needed, it’s not self-evident that all
personnel need to be ALS practitioners.
When determining the
most appropriate complement of ALS crews, serious consideration should be given
to five key factors that may significantly influence patient outcomes and
system viability:
- ALS practitioner proficiency: The first consideration is whether the proficiency of
a practitioner’s skill performance improves with increasing experience and
patient contact volume. This is especially important to asses regarding
critical skills less often used and more difficult to perform, such as
endotracheal intubation, IV insertion, rapid sequence intubation or
cricothyrotomy.
- Treatment time:
The second consideration is the impact of the number of ALS providers
composing the crew has regarding treatment time at the scene, thereby
affecting transport to definitive care, and any resulting impact on the
morbidity and mortality of patients.
- Error rates: The
third consideration to assess is whether the number of ALS providers
treating a patient in the field affects the errors committed by those
practitioners in the assessment of patients, medications administered or
skills performed.
- Practitioner shortage: Reports are now commonplace regarding the shortage of
paramedics in the country. Modifying ALS crew configuration could expand
or contract the labor pool and impact a system’s ability to fully staff
necessary units.
- Financial sustainability of the EMS system: Because EMS systems use an intense amount of human
resources, the cost of which compose a majority of the annual operating
expenses for most systems, crew complement is an important consideration
for the long-term financial viability of EMS. Does the ALS crew complement
substantially affect the cost of operations?
Taking these
considerations into account, this article examines the fundamental question: Is
an ALS ambulance crew complement of two practitioners, one certified/licensed
to the level of emergency medical technician–basic (BLS Provider) and the other
to paramedic (ALS provider), adequate to result in acceptable patient outcomes?
Further, is this model equal to, worse than or superior to a crew complement of
two paramedics?
The Current Literature
A search on best
models of ambulance crew configurations yields little in terms of original
research trials. Most likely this is because of the difficulty in studying
patients who received two ALS providers vs. one ALS provider during the same
acute medical condition.
Several publications
exist outside of the U.S., with vastly different EMS systems, which makes
comparisons of various numbers of ALS providers extremely challenging.
In 1999, the Canadian
OPALS study demonstrated no benefit of ALS over BLS for cardiac arrest.10 However, that was based on a BLS system with early
defibrillation and significant bystander CPR.
Similarly, in a
2003 USA Today survey of 50 major cities, the lowest number of
paramedics per capita had the highest cardiac arrest survival rates.11
Additionally, worse
outcomes are associated with trauma provided by ALS, which is most likely due
to additional procedures performed by ALS and increased scene times. One study
found that provider skills for intubation is based on frequency of the skill
performed and its association with cardiac arrest survival.12,13 Based on increased utilization and success of CPAP as well
as the deprioritization of intubation during cardiac arrest, the overall
utilization of intubation is decreasing, yet the need for paramedic expertise
in intubation remains the same.
A study conducted with
the Mississippi Department of Health evaluated the volume-outcome relationship
of paramedics.14 This 14-year study estimated the
relationship between experience accumulation and performance of paramedics who
responded to approximately 175,000 general trauma calls. A greater volume of
paramedic experience was significantly related to reduced total prehospital
time and time on scene. The authors concluded that retention of skills is
accomplished by increased volume.
A 2010 study of 10,298
out-of-hospital cardiac arrests evaluated whether more paramedics (three or
more vs. two paramedics) resulted in improved outcomes. No difference was found
in survival to discharge, and return of spontaneous circulation wasn’t
associated with a greater number of paramedics.15
A similar paper
evaluated two paramedic vs. single paramedic crews in simulated cardiac arrest
scenarios. They found that additional paramedics on the crews resulted in more
errors than with single paramedic crews.16
An unpublished thesis
paper in 2006, a three-year retrospective review of the Wake County EMS System,
compared a two paramedic crew vs. a one paramedic crew. During the years
studies, half of Wake County had one paramedic per crew and half of their
system had two ALS providers per crew. Inclusion criteria were cardiac arrests,
respiratory emergencies, cardiac emergencies and traumas that required emergent
transport utilizing lights and sirens. No statistically significant difference
was found regarding scene times, intubation success and first-pass success. Not
surprisingly, the two paramedic crews had a high rate of statistically
significant IV success (0.89 vs. 0.87; p=0.04), but not first attempt success.17
An Australian study
evaluated scene time difference in 1,537 prehospital cases with all-paramedic
crews vs. mixed crews. All-paramedic crews had a statistically significant
longer scene time than mixed crews (16.92 min. vs. 15.95 min.; p=0.002). There
were no differences in procedure failure rates including intubation and
intravenous insertion.18
Researchers in
Columbus, Ohio, retrospectively studied ambulance staffing models in a
metropolitan, fire-based EMS system. Paramedic-basic (PB) crews were compared
with paramedic-paramedic (PP) crews. There were no differences between PB vs.
PP crews in times to ALS interventions, time to IV insertion, IV success rates
and protocol violation rates. PP crews did have shorter median scene times than
PB crews (p=0.01).19
In 2017, Santa Cruz,
Calif., reported a complete change of their EMS system from a dual paramedic
crew configuration system to a single paramedic crew configuration.20
Legal Considerations
A review of state
statutes and regulations show the majority of states require only a single
paramedic on the crew that will staff an ALS ambulance. Two states, New Jersey21 and Delaware,22 mandate two
paramedics staff an ALS unit, but don’t require the ALS unit be capable of
transporting patients.21,22
Massachusetts, Wisconsin
and Utah laws require the assignment of two paramedics to a response, but don’t
require the paramedics to be on the same unit.23–25
Among the states
requiring only a single paramedic ALS unit, regulations for non-paramedic crew
members vary. For example, South Dakota and West Virginia regulations allow an
ALS ambulance to operate with a paramedic and a driver meeting requirements
established by the Department of Health.26,27 Oklahoma
regulations are similar, specifying the driver must be certified as an
emergency medical responder.28
Other states and
territories, such as Oregon, Virginia and Washington D.C., specify that an ALS
ambulance must have a paramedic and another crew member certified at or above
the EMT-basic level.29–31
Arizona varies the requirement
for the crew member depending on whether the ambulance crew services a rural or
wilderness area and also considers recent census data.32
A review by the New
Jersey state legislature’s Office of Legislative Services in 2013, determined
the following:
- “A majority of states require staffing [of ALS units]
by two EMTs” but “do not specify whether both…must be capable of
performing paramedic skills.”
- “Several other states require ALS ambulances to be
staffed by only one certified emergency medical responder—i.e., one
paramedic or one EMT.
- “In summary, … it does not appear that any other state
[except New Jersey] requires ALS vehicles to be staffed by a minimum of
two paramedics…”
Local governments and
agencies typically have latitude to impose staffing requirements that exceed
the state requirements and may staff ambulances with two or more paramedics.
Financial
Considerations & Impact of ALS Crew Configuration
A basic analysis of
the financial impact on an EMS system can be done concerning the complement of
ALS crews. Based on several fundamental assumptions, annual expense
calculations can be performed to determine the operating costs of the crew
complement configurations considered in this article.
The following
assumptions are based on general industry knowledge about operating expenses
and common elements present in most organizations. Some variance exists,
depending on the organizational design, corporate structure and deployment
models that are employed throughout the country.
One of the most widely
variable costs are those associated with benefits provided to staff by the
employer. These include health plan benefits, paid time off, uniform
allowances, tuition reimbursement, retirement plans, payroll taxes and others.33,34 However, a general assumption can be used based on average
experience reported by the U.S. Department of Labor.34
For the purpose of
this analysis, operating and capital costs, other than personnel expenses,
weren’t included, since crew complement does not necessarily affect them.
The assumptions used
for this analysis included the following:
- The calculations are based on one full-time ALS unit;
- A full-time unit is defined as one unit operating
24/7/365;
- The average wage used for a paramedic is $23.50 per
hour;33
- The average wage used for an EMT-basic is $18.48 per
hour;33
- Overtime is calculated at 10% of total annual hours
(876 hours annually);
- Overtime wages are calculated at time and a half
($35.25 per hour for paramedics and $27.72 per hour for EMT-basics); and
- The cost of benefits is calculated at 46.5% of base
wages, or 31.7% of total compensation.34
This brief analysis
shows that an ALS crew complement of one ALS practitioner with one BLS provider
is 10% less expensive annually than a two ALS crew member team. In addition, a
single ALS practitioner crew is 44% less expensive than a two-member crew
composed of one ALS provider and one BLS member. In a system of 10 ALS units
with two paramedic providersm this equates to a savings of approximately
$750,000 per year to the healthcare system.
Conclusion
Understanding ideal
crew configuration is vital to maintain EMS systems. There’s a lack of evidence
demonstrating the need for a second ALS provider on a general ALS response.
Implications of overstaffing may result in more patient care errors and
draining of financial resources which could be spent on additional
state-of-the-art medical equipment or number of units resulting in better
system performance and patient care.
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