Page 42 - Journal of Special Operations Medicine - Spring 2014

allocated to them. Negative values of S (case I) indi-
cate that transportation resources are severely limited
Figure 3 QR code for accessing the mobile app
for the ReSTART calculator. in comparison with the number of delayed patients and
thus ReSTART prioritizes those patients (region A in
Figure 2). This is because when resources are severely
this calculator available online, this is not meant to sig- limited, it is not possible to transport all the patients
nify that calculations must be done to at least use the within a time window that will allow a reasonably high
concepts illustrated here. survival probability for all the patients; therefore, it is
best to use the resources first for the delayed patients,
Then, the ReSTART triage and prioritization policy can who have a higher chance of benefiting. In effect, in these
be described as follows: situations of severe resource constraint, the immediate
patients are now essentially reclassified as expectant
Step 1: Classify patients according to START criteria, by default (although they still may be prioritized prior
with management decisions being made per START pro- to minor injury patients, who have almost no risk of
tocols until the number of casualties is known. mortality). If S is positive and large (case II), this means
that resources are relatively abundant and one should
Step 2: Calculate the parameter S.
use START as currently practiced by giving priority first
Step 3: Determine the priorities among the immediate to immediate patients and then to the delayed patients
and delayed patients as follows: (region B in Figure 2). When S is positive but small (case
III), the resource limitation is at a medium level. This
(I) If S ≤ 0, transport all the delayed patients first, means that there is some amount of time during which
and then any immediate patients that still it is beneficial to give priority to the immediate patients,
survive. but at some point, priority should switch to the delayed
patients. Specifically, this switch should occur at time S,
(II) If S ≥ IR/V, transport all immediate patients
first and then all remaining surviving delayed which is some time before the deterioration rate of the
patients. delayed patients exceeds that of the immediate patients.
(III) If 0 < S < IR/V, transport immediate patients ReSTART, as described earlier, makes sense intuitively:
for S minutes or until there are no more im- observe that S tends to be larger (and thus the resources
mediate patients. Then, start transporting de- tend to be less limited) when there are few delayed pa-
layed patients and continue until there are no tients, when travel time to the hospital is short, and
more delayed patients. Finally, continue with when the number of ambulances is large. Precisely why
the transportation of any remaining immediate this particular calculation of S should be expected to
patients. give good results is supported by mathematical analysis
we have described previously. Because S can be calcu-
8
Note that steps 2 and 3 can be repeated as often as lated quickly using only a few pieces of information, it
necessary as additional patients are found or as triage can be updated as frequently as needed: for example,
classifications are corrected. Although the largest ben- when patients are re-triaged and change classification
efit is obtained when steps 2 and 3 are completed as from immediate to delayed or vice versa, or when the
soon as possible after the incident, in most scenarios Re- number of available transportation resources changes.
START will begin by prioritizing the immediate patients With this recalculation, providers can better assess how
just as START does; thus, the standard implementation conditions are changing at the scene—that is, whether
of START can be used until it is possible to obtain the resources are becoming more restricted (decreasing S)
information needed to complete steps 2 and 3. In this or less restricted (increasing S). In short, calculation of S
way, one can see that ReSTART is not a replacement for allows providers to get a “snapshot” of resource avail-
START, but rather a decision support tool that can be ability by combining several pieces of information into
used in addition to START to help improve prioritiza- a single parameter that measures the extent to which
tion once sufficient information about the patient distri- resources are restricted.
bution and resource availability is available.
It is important to emphasize the fact that ReSTART
In this description, S can be seen as a measure of how re- does not change the way patients are classified but calls
stricted transportation resources are in comparison with for using patients’ triage class information more intel-
the size of the mass-casualty incident and composition ligently by considering resource restrictions. Calculating
of the patient population and IR/V is a rough approxi- the resource limitation (S) is a simple method to use since
mation for the expected total time needed to transport it requires a single computation to determine what spe-
all immediate patients if all available ambulances are cific prioritization scheme to employ. The only possible

34 Journal of Special Operations Medicine Volume 14, Edition 1/Spring 2014