Military anti-shock trousers (MAST), or pneumatic anti-shock garments (PASG), are medical devices used to treat severe

blood loss Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, v ...

. The device is usually applied to the patient's

pelvis The pelvis (: pelves or pelvises) is the lower part of an Anatomy, anatomical Trunk (anatomy), trunk, between the human abdomen, abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also c ...

abdomen The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal ...

, and lower parts of the body and is composed of man-made inflatable air bladders. The device is designed to transfer blood away from the above described body parts and into the upper body by applying pressure. There is significant controversy over the use of MAST. Initial studies in the 1970s suggested that the application of MAST auto-transfused up to 20 percent of the patient's blood to the upper body. However, by using human and dog models, subsequent studies in the 1980s disputed the claim, showing that lower than 5 percent of the blood was actually auto-transfused with the device. In addition, the usage of the device may cause further complications such as

compartment syndrome Compartment syndrome is a serious medical condition in which increased pressure within a Fascial compartment, body compartment compromises blood flow and tissue function, potentially leading to permanent damage if not promptly treated. There are ...

and lower extremity

ischemia Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems ...

. Most modern EMS and trauma programs have abandoned their use following data from a Cochrane review which indicated no mortality or survival benefit when MAST were applied to patients in shock. I. G. Roberts et al. sought to quantify the effect on mortality and

morbidity A disease is a particular abnormal condition that adversely affects the structure or function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical conditions that are asso ...

of the use of MAST in patients following trauma, and published the data in the Cochrane Database of Systematic Reviews.Roberts IG, Blackhall K, Dickinson KJ.
Medical anti-shock trousers (pneumatic anti-shock garments) for circulatory support in patients with trauma
. ''Cochrane Database of Systematic Reviews'' 2007, Issue 2. Art. No.: CD001856. .

References

U.S. Patent No. 3,933,150
* Grant, HD, Murray Jr., RH

''Emergency Care, 2nd ed''. 1978. * Davis JW, McKone TK, Cram AE
"Hemodynamic effects of military anti-shock trousers (MAST) in experimental cardiac tamponade"
''Annals of Emergency Medicine''. 1981 Apr;10(4):185–6. * Traverso LW, Lee WP, DeGuzman LR, Bellamy RF
"Military antishock trousers prolong survival after otherwise fatal hemorrhage in pigs"
''Journal of Trauma''. 1985 Nov;25(11):1054–8. Medical equipment Military medicine {{Medical-stub

See also

References