Military anti-shock trousers

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Military anti-shock trousers (MAST), or pneumatic anti-shock garments (PASG), are medical devices used to treat severe blood loss. The device is usually applied to the patient's pelvis, abdomen, 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 and lower extremity ischemia. [1] 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. [2] [3]

I. G. Roberts et al. sought to quantify the effect on mortality and morbidity of the use of MAST in patients following trauma, and published the data in the Cochrane Database of Systematic Reviews. [4]

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<span class="mw-page-title-main">Non-pneumatic anti-shock garment</span> Device used to treat hypovolemic shock

The non-pneumatic anti-shock garment (NASG) is a low-technology first-aid device used to treat hypovolemic shock. Its efficacy for reducing maternal deaths due to obstetrical hemorrhage is being researched. Obstetrical hemorrhage is heavy bleeding of a woman during or shortly after a pregnancy. Current estimates suggest over 300,000 women die from obstetrical hemorrhage every year with 99% of cases occurring in developing countries; many of these deaths are preventable. Many women in resource-poor settings deliver far from health-care facilities. Once hemorrhage has been identified, many women die before reaching or receiving adequate treatment. The NASG can be used to keep women alive until they can get the treatment they need.

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References

  1. Chatham, Strecker-McGraw (2022). "MAST Pants". National Center for Biotechnology Information. PMID   30521204.
  2. Mattox, Kenneth L. (January 2003). "Permissive Hypotension". 8:1. trauma.org.{{cite journal}}: Cite journal requires |journal= (help)
  3. Bledsoe, Bryan (November 30, 2003). "EMS Myth #1: Medical Anti-Shock Trousers (MAST) autotransfuse a significant amount of blood and save lives". EMS World. Retrieved November 14, 2017.
  4. 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. doi : 10.1002/14651858.CD001856.