Page 94 - Journal of Special Operations Medicine - Fall 2015

There is little scientific evidence available to definitely tourniquets that have been in place for more than 6
declare the upper time limit of the “safe” amount of time hours, unless at a definitive care facility.
for a tourniquet to be left on. Even a recent extensive
review in the orthopedic literature of use of tourniquets In addition,
in the operating room was unable to definitively answer
the question. Several experts feel that conversion may be • Less than 2 hours after application is considered safe
9
attempted up to 6 hours after initial tourniquet applica- (attempt conversion)
tion. The longer a tourniquet is in place, the more tissue • 2–6 hours is likely safe, but the upper safe limit has not
10
destruction occurs and the higher the risk for reperfusion been scientifically determined (attempt conversion)
injury and kidney failure. This time window is influenced • More than 6 hours requires caution (field conversion
by the amount of ischemic tissue distal to the tourniquet not advised) 10
(proximal worse than distal and leg worse than arm), the
temperature of the extremity (warm worse than cold), Plus-1 Tourniquet
and the hemodynamic status of the patient. Add one loose tourniquet to each extremity to which a
tourniquet has already been applied (“Plus 1”). This is
To demonstrate the difficulty in defining a definitively done for two reasons. The first is if the tourniquet that
safe time limit for conversion, there is a case with docu- is already in place breaks during the conversion process,
mented total tourniquet time of up to 16 hours. In this there is already a backup in place ready to be tightened.
case, the extremity was exposed to the cold environment Tourniquets are subject to environmental degrada-
and the tourniquet was placed distally on the upper ex- tion 17,18 and significant wear and tear during applica-
tremity. This patient had residual motor and sensory tion. In a recent After Action Report distributed with
19
deficits but no systemic complications of reperfusion. 11 the 2014 Committee on TCCC meeting minutes, 10%
of the tourniquets used in a six-patient casualty incident
Conversion is the deliberate process of trying to ex- broke while being applied. The second reason is that it
change a tourniquet for a hemostatic agent or a pressure is difficult to determine where the patient is on the re-
dressing. Conversion is an essential skill for all medical suscitation curve. Administration of fluids (crystalloids,
personnel to learn. Tourniquets cause pressure injury to colloids, or blood) and/or ketamine has the potential
the tissue that is being directly compressed and ischemic to raise blood pressure beyond the hypotensive target.
injury to the tissue that is no longer perfused. Conver- A second tourniquet in place reduces bleeding time if
sion has been advocated since at least World War II bleeding suddenly recurs (Figures 1 through 7).
12
and since the start of TCCC development, but a step-
13
by-step algorithm for military personnel has not been With the Plus-1 tourniquet in place, loosen the first
updated since 2005. Since 2003, hemostatic agents tourniquet. If no bleeding from the wound is noted, then
10
have been developed and have evolved significantly, leave both tourniquets in place but not tightened and
14
as has the published literature on the use of tourni- dress the wound. If bleeding is noted, apply a hemostatic
quets. Articles from 2007 and 2008 discussing the use
of tourniquets in the civilian setting provided a more Figure 1 A simulated patient with a single tourniquet placed
comprehensive algorithm for tourniquet conversion but over the thigh. The tourniquet is placed high and tight in
not did not account for military-specific concerns relat- a proximal position, emphasizing the need for immediate
ing to: prolonged transport times, the need to reattempt hemorrhage control in the Care Under Fire stage.
tourniquet conversion during patient re-evaluations, Diagnostic maneuvers such as exposure and wound
and the potential for tourniquet failure if retightening examination are reserved for the Tactical Field Care stage.
is needed. 15,16 Our paper also introduces the concept of The tourniquet remains visible and is marked with time
the “Plus-1” tourniquet to the algorithm of treating any of application.
patient to whom a tourniquet is applied.

Tourniquet Conversion Procedures
When should tourniquet conversion occur? The defini-
tive answer to this is unknown, but generally:

• Conversion should be attempted as soon as tactically
appropriate, but no later than 2 hours after initial
tourniquet application.
• Conversion should be attempted with each progres-
sive movement to the next level of care, but not for

82 Journal of Special Operations Medicine Volume 15, Edition 3/Fall 2015