Biomedical Engineering Reference
In-Depth Information
rural hospital, 10 victims from a local manu-
facturing accident might be considered a mass
casualty event. In a metropolitan area, several
hundred victims would be manageable within
system resources. In an event involving thousands
of victims, preserving a functioning health care
system will require a move to altered standards
of care. It may also be necessary to create both
pre-hospital operations and alternate care sites to
supplement hospital care.
The term “altered standards” has not been
defined, but generally is assumed to mean a shift
to providing care and allocating scarce equipment,
supplies, and personnel in a way that saves the
largest number of lives in contrast to the traditional
focus on saving individuals. For example, it could
mean applying principles of field triage
2
to deter-
mine who gets what kind of care. It could mean
changing infection control standards to permit
group isolation rather than single person isolation
units. It could mean limiting the use of ventilators
to surgical situations. It could mean creating alter-
nate care sites from facilities never designed to
provide medical care, such as schools, churches, or
hotels. It could also mean changing who provides
various kinds of care or changing privacy and
confidentially protections temporarily.
Two mass casualty scenarios were developed by the panel
of experts to help identify how care delivered at the event
scene or pre-hospital setting, hospital, and alternate care
sites would vary from care provided under normal
circumstances.
Scenario 1. Multiple, simultaneous explosions
A series of multiple dirty bombs have been set off
simultaneously throughout a large metropolitan subway
system. The city's hospitals also have been targeted and
approximately 40 percent of the hospitals are no longer
operational. There are an estimated 10,000 victims.
Scenario 2. Biological agent release
A highly lethal communicable biological agent with a set but
initially unknown incubation period has been released in a
heavily populated area. Diagnosis is dependent on
laboratory tests. Medical staffs are required to use personal
protection equipment. Treatment requirements include
patient isolation and the use of ventilators; however, the
impact and effectiveness of treatment is unknown.
Figure G.1
Two Mass-casualty scenarios used to identify
anticipated changes to care delivery.
a large number of casualties upon detonation and
place an immediate demand on all aspects of the
health care system. The biological scenario would
develop more slowly, with its peak impact occur-
ring at the end of an unknown incubation period.
The examination of these scenarios revealed
that the explosive and biological terrorism mass
casualty scenarios are likely to share common
elements, but also raise issues that are specific
to the nature of each event and the speed with
which the event places demands on the health
care system. The following discussion highlights
these common elements. Event-specific issues for
each scenario appear in Figures G.2 and G.3 and
are organized by setting (scene [or pre-hospital],
hospital, and alternate care sites).
Hypothetical Scenarios Illustrating
Changes in the Delivery of Care in
Response to a Mass Casualty Event
Two hypothetical mass casualty scenarios were
developed by the panel of experts to help illustrate
specific ways in which care standards would have
to change in response to a mass casualty event
(see Figure G.1). The first scenario involves the
simultaneous explosion of multiple dirty bombs in
a metropolitan area. The second scenario involves
the release of a biological agent. The use of these
two scenarios facilitates the examination of the
impacts and implications of two serious events that
differ in nature and occur at different velocities.
For example, the explosive scenario would produce
Changes in Care Delivery Common to
Two Scenarios
At their peaks, both the explosive and biological
mass casualty scenarios are likely to involve the
following:
2
The term triage refers to the process of sorting victims according to their need for treatment and the resources available.
