Page 35 - Journal of Special Operations Medicine - Spring 2015

not more than 2 hours after initial application. If the as soon as possible, considering the tactical and clini­
initial conversion attempt is unsuccessful due to re­ cal situation. All wounds must be monitored closely for
bleeding, repeated attempts to convert the tourniquet rebleeding. Major traumatic amputations require con­
should not be performed due to the risk of incremen­ tinued use of a tourniquet until arrival to surgery, and
tal exsanguination. In some cases, a second attempt to conversion to a hemostatic or pressure dressing should
convert the tourniquet may be indicated, particularly if not be attempted.
conditions for wound management have significantly
improved due to better lighting, supplies, or manpower. Cooling ischemic muscle reduces damage to the mus­
cle. 60­62 Even a 2°C to 3°C reduction in skeletal muscle
Tourniquets applied in situations where assessment temperature may reduce muscle necrosis after extended
67
is very limited, such as CUF, mass casualty events, or tourniquet application. Cold environmental tempera­
multiple life­threatening injuries in the same casualty, tures were credited for successful limb salvages after
24
should be applied high and tight (as proximal as possi­ tourniquet applications up to 8 hours in World War II.
ble) on the injured limb to avoid inadvertent placement Exposure of the limb to take advantage of cool envi­
distal to an unseen injury. ronmental temperatures was also recommended by an
expert panel convened in 2003. Packing of an injured
38
To minimize the damage that may be induced by the limb with snow or ice, however, is not recommended,
tourniquet, care providers are instructed to follow cer­ due to the risk of further tissue injury. 49
tain rules of thumb when applying or repositioning
tourniquets during TFC or TACEVAC care: Place the As demonstrated by the Ranger model, medical training
tourniquet as distally as possible, but at least 5cm proxi­ must also be incorporated into each unit’s combat train­
mal to the injury; avoid joints; apply the tourniquet over ing exercises and real­world training scenarios, rather
exposed skin to avoid slipping; and convert to hemo­ than just being rehearsed independently under static
static or pressure dressing whenever possible. 31 conditions. 34,64 Teach tourniquet application during field
training and CUF exercises. Classroom training alone is
Up to 24% of limbs have two tourniquets placed. King not adequate.
et al. described one casualty with three tourniquets
placed far apart from one another making them act in­ An algorithm for tourniquet placement during CUF and
dependently as single, independent, and narrow devices reassessment during TFC and TACEVAC care is illus­
rather than together side by side as if one wide device. trated in Figure 1.
3
When ongoing limb bleeding or distal pulses were de­ Conclusions
tected (generally after exposing the wound), medics
tightened the tourniquets under supervision of a sur­ 1. A decrease in the frequency of preventable deaths
geon until distal pulses became absent. All medics were has been achieved though widespread training, and
surprised as to how tight a tourniquet must be to stop dissemination and use of tourniquets. The likelihood
arterial flow; that is, to change a venous tourniquet into of tourniquet morbidity had been reduced through
an arterial tourniquet. 3 selection of better devices, more training of potential
users, and more rapid evacuation. To minimize com­
TCCC courses must reinforce the distinction between plications, it is important that training emphasize
venous and arterial tourniquets in patients without am­ early conversion of tourniquets that are no longer
putations. Venous tourniquets do not stop arterial in­ needed; tourniquets must be frequently reassessed to
flow to an injured limb but promote venous congestion. ensure that hemorrhage is stopped and venous tour­
Venous tourniquets soon increase bleeding from injured niquets avoided, particularly when evacuation time
limbs and must be avoided. 19,66 is long.
2. Tourniquets that are no longer needed should be con­
An increase in blood pressure during resuscitation may verted to hemostatic or pressure dressings as soon as
20
result in rebleeding or return of the distal pulse. Medics possible if the criteria for safe removal are met to re­
should also be aware that initial tourniquet placement duce tourniquet pain and minimize the risks of com­
may be effective, but within a minute, muscle tension plications. If the tourniquet is still on the extremity 2
under the tourniquet may lessen, causing the tourniquet hours after placement, a mandatory reassessment of
to become ineffective. Ongoing reassessment of tour­ the continued need for the tourniquet should occur.
44
niquets is necessary. 3. The goals of tourniquet placement are to stop both
bleeding and the distal pulse. Tactical and clinical
TCCC courses must reinforce the need to attempt conver­ situations dictate which goal(s) can be monitored;
sion of tourniquets to hemostatic or pressure dressings however, the likelihood of maximum benefit and

TCCC Limb Tourniquet Guidelines Change 14-02 25