Mast Pants

[Eyegor]

New York still has them but the protocols call for their use only for profound hypotension with pelvic instability. I may be old school but I think they still have their place in rural BLS services. And I believe they have other uses besides the written protocol. YMMV.

P.S. I used to use them a fair amount but haven't in years. Mostly because the areas I now serve usually have readily available ALS.

[chbare]

I may be old school but I think they still have their place in rural BLS services. And I believe they have other uses besides the written protocol. YMMV.

Not trying to pick on you; however, what is your rationale for taking this stance?

Take care,

chbare.

[Eyegor]

Not trying to pick on you; however, what is your rationale for taking this stance?

Take care,

chbare.

Fair question, and don't worry I have thick skin. In NYS at the BLS level there is no options for fluid resuscitation. Therefore when significant blood loss is noted or suspected the only option is to maintain what the patient still has on board. Therapeutic hypotension is one thing, exsanguination is quite another. My goals in this instance is to keep the brain, and vital organs in the chest cavity perfused. I want every trick available. Trandelenburg, direct pressure, MAST, tourniquets, etc., etc. One more tool in the tool box.

Another mild side track. It was once common practice to apply MAST (but not inflate) to any trauma patient who you feared may decompensate. Then if your ongoing assessment showed a patient deteriorating you could rapidly inflate. If the garment is already on the patient this can be accomplished very rapidly. Of course, you had to watch for negative outcomes such as PE, or increased bleeding of injuies superior to the garment. We even understood the concept of "tritating" the MAST. If it was decided to use for fx management, then only the compartments necessary would be inflated and then never ever to the point where distal perfusion was profoundly effected. All of this took place in an environment where paramedics were only seen in "the city" and there was this mythical chariot called a helicopter but even that was at least 45 minutes away if available.

MAST will probably never again be used at the level it once was, but that doesn't mean it is no longer useful at all.

[chbare]

Fair question, and don't worry I have thick skin. In NYS at the BLS level there is no options for fluid resuscitation. Therefore when significant blood loss is noted or suspected the only option is to maintain what the patient still has on board. However, aggressive fluid resuscitation in the field may not be helpful and may be harmful in some cases when looking at current EBM. Therapeutic hypotension is one thing, exsanguination is quite another. However, increasing the blood pressure may in fact lead to additional complications and worsen bleeding. This is especially true of internal hemorrhage. My goals in this instance is to keep the brain, and vital organs in the chest cavity perfused. I want every trick available. Trandelenburg, direct pressure, MAST, tourniquets, etc., etc. One more tool in the tool box. The current data is inconclusive when considering MAST, there is a scant amount of data regarding the "shock" position with the current EBM showing no conclusive benefit. I cannot see how allowing BLS providers to access modalities that are not proven to benefit would be helpful.

Another mild side track. It was once common practice to apply MAST (but not inflate) to any trauma patient who you feared may decompensate. Then if your ongoing assessment showed a patient deteriorating you could rapidly inflate. If the garment is already on the patient this can be accomplished very rapidly. Of course, you had to watch for negative outcomes such as PE, or increased bleeding of injuies superior to the garment. We even understood the concept of "tritating" the MAST. If it was decided to use for fx management, then only the compartments necessary would be inflated and then never ever to the point where distal perfusion was profoundly effected. All of this took place in an environment where paramedics were only seen in "the city" and there was this mythical chariot called a helicopter but even that was at least 45 minutes away if available.

MAST will probably never again be used at the level it once was, but that doesn't mean it is no longer useful at all. It was never proven to be particularly useful in the first place. The evidence is still all over the place.

Take care,

chbare.

[Robbyemt]

I'm in Western NY and we still have them on our rigs but I think they took them out of our protocos. Good question ... I will look into it.

Now to answer question about using them... I have used them on a trauma/ejection/rollover pt that had multiple fractures and low BP. They worked great. The discussions flip flop whether or not you are causing an excellerated compartment syndrome and doing more harm than good. Secondly, you don't want to overload these patients with fluids either. Optimally you would like to have whole blood for replacement therapy but now we're going to a whole new level or care.

Rob

I was watching a old Squad 51 (Emergency), and they put mast pants on a patient for

unstable BP with hip trauma. In Michigan we dont carry them any more. anyone still carry them/ have it in your protocols. Just wondering?

[brentoli]

They are still in the Indiana Statues for required equipment. Locally if we have a protocol for it the word mast is in 2pt font.

[Richard B the EMT]

They were originally known as "Military", as they had some background in Fighter Jet Jockey flight suits, to prevent them from passing out when "pulling 'G's".

[Eyegor]

Chbare,

I have read most of the same studies you sight and can't fault the science. But in the realm of outcome based medicine, you have to look at outcomes. MAST works. I've seen it. I have also seen perfusing and awake patients die in the ER when the MAST is rapidly removed. We all know that is a no-no but.....that's not what we're discussing here. Now for the flip side of the coin. Have BLS providers ever killed or caused permanent deficit in anybody who otherwise would have survived by using MAST? I don't know the answer and I don't think anyone else does either.

MAST obviously should not be a 1st line or stand alone treatment. I'm even OK with states removing them from the mandatory equipment lists based on their inconclusive results and infrequency of use. But when studies keep having conclusions with the words may or might or inconclusive then IMHO MAST deserves more than a shelf in the museum.

Thank you for the debate and exchange of information. I hope everyone else finds it as interesting and/or helpful as I.

[medic82942003]

I cant remember what episode it was, but where I live they show Emergency at 0900 and 1500.

Many of the episodes still make you think about what to do? I watch it on Retro TV. At first when

I started watching the re runs I thought How stupid they are still showing this stuff, but except

for some of the Medical TX, alot of the episodes still apply to today. Some things change, but alot stays the same. Be safe.

[Richard B the EMT]

A visitor to New York for the 1990 Tennis "Open" was stabbed in the chest, while attempting to protect his family from a mugging.

Under protocols then in use, the responding crews placed him into a MAST, inflated the 3 compartments, and proceeded to transport. He exanguenated through the chest stab wound.

In the ensuing firestorm of critisizm in the local, state and national medias, protocols were changed to not use MAST for penetrating chest trauma, and in following years, statewide training included MAST, but the equipment was removed from the NYC EMS (pre FDNY merger) ambulances.

Find the article about the attack, but not mentioning the MAST, and NYS DoH policies, below.

http://www.queenstribune.com/anniversary20...rianwatkins.htm

http://www.health.state.ny.us/nysdoh/ems/policy/s97-04.htm

<H1 id=pagetitle>Medical Anti-Shock Trousers</H1>

Advisory No. <A name=S97-04>97-04

Date Approved: August 7, 1997

New York State Department of Health Bureau of Emergency Medical Services

Note: This advisory guideline announces important changes in the Statewide Basic Life Support Adult and Pediatric Treatment Protocols. Revised copies of each of the protocols affected by these changes are attached. Revised copies of each of the protocols affected by these changes are also being sent to all emergency medical services agencies statewide. Regional Emergency Medical Advisory Committees, and regional, system, and service medical directors are directed to facilitate use of the revised protocols at the local level, and are further advised to modify local protocols, policies, and procedures accordingly.

Current Statewide Basic Life Support Adult and Pediatric Treatment Protocols stipulate that Medical Anti-Shock Trousers (MAST), also known as the Pneumatic Anti-Shock Garment (PASG), should be inflated if the systolic blood pressure is below 90 mm Hg in adults or below 70 mm Hg in children and signs of inadequate perfusion are present, if MAST (PASG) are available. The State Emergency Medical Advisory Committee has reviewed these protocols, and concludes, on the basis of recent scientific evidence, that prehospital MAST (PASG) use in New York State should be considered only in adult major blunt trauma with severe hypotension (systolic blood pressure < 50 mm Hg) and hypotension (systolic blood pressure < 90 mm Hg) associated with unstable pelvic fracture.

In 1989, Mattox et al, in a prospective randomized study of 911 adult trauma patients, mostly with penetrating injuries, found that MAST (PASG) use was associated with longer scene times, and worsened the survival of adult patients with systolic hypotension (BP < 90 mm Hg) as well as those with primary thoracic injuries who presented in traumatic cardiac arrest. In 1992, Cooper et al, in a retrospective study of the efficacy of MAST (PASG) use in 436 pediatric trauma patients, mostly with blunt injuries, from the National Pediatric Trauma Registry who presented in hypotensive shock, found similar results. In 1993, Cayten et al reported the results of a retrospective study of MAST (PASG) use in 629 hypotensive adult trauma patients which concurred with Mattox's findings, although they were able to demonstrate a small but statistically significant survival advantage in severe hypotension (BP < 50 mm Hg). While there have been no prospective studies and no published trauma registry data in support of MAST (PASG) use for hypotension associated with unstable pelvic fractures, retrospective reviews and cases reports consistently support MAST (PASG) use in such circumstances.

In 1997, O'Connor et al performed a collective review of the scientific literature as an evaluation of MAST (PASG) in various clinical settings. On the basis of this review, Domeier et al developed a position paper on use of MAST (PASG) for the National Association of EMS Physicians, the Summary Recommendations from which, as they pertain to trauma, are summarized below.

MAST (PASG) are "usually indicated, useful, and effective" (Class I evidence) for:

• None.
  

MAST (PASG) are "acceptable, of uncertain efficacy, [although the] weight of evidence favors usefulness and efficacy" (Class IIa evidence) for:

• "Hypotension due to suspected pelvic fracture;
  
• Severe traumatic hypotension (palpable pulse, blood pressure not obtainable). *"
  

MAST (PASG) are "acceptable, of uncertain efficacy, may be helpful, probably not harmful" (Class IIb evidence) for:

• "Penetrating abdominal injury;
  
• Lower extremity hemorrhage (otherwise uncontrolled); *
  
• Pelvic fracture without hypotension; *
  
• Spinal shock. *"
  

MAST (PASG) are "inappropriate, not indicated, may be harmful" (Class III evidence) for:

• "Adjunct to CPR;
  
• Diaphragmatic rupture;
  
• Penetrating thoracic injury;
  
• Pulmonary edema;
  
• To splint fractures of the lower extremities;
  
• Extremity trauma;
  
• Abdominal evisceration;
  
• Acute myocardial infarction;
  
• Cardiac tamponade;
  
• Cardiogenic shock;
  
• Gravid uterus."
  

* Data from controlled trials not available. Recommendation based on other evidence.

The literature cited supports the conclusion that the role of MAST (PASG) in the prehospital emergency medical care of adult and pediatric patients is extremely limited. The State Emergency Medical Advisory committee agrees with the National Association of EMS Physicians that the weight of the evidence favors the usefulness and efficacy of MAST (PASG) only for adult major blunt trauma with severe hypotension (systolic blood pressure < 50 mm Hg) and hypotension (systolic blood pressure < 90 mm Hg) associated with unstable pelvic fracture, a position which is consistent with the 1997 Edition of the Advanced Trauma Life Support Course of the American College of Surgeons.

The State Emergency Medical Advisory Committee (SEMAC) therefore recommends their use under these circumstances, although Regional Emergency Medical Advisory Committees (REMAC) may prescribe their use under other circumstances to address specific local conditions. The Statewide Basic Life Support Adult and Pediatric Treatment Protocols are being modified to reflect this change, and Regional Emergency Medical Advisory Committees, and regional, system, and service medical directors are advised to modify local protocols, policies, and procedures accordingly.

Selected References

1. Mattox KL, Bickell W, Pepe PE, et al: Prospective MAST study in 911 patients. J Trauma 1989;29:1104-1112.
   
2. Cooper A, Barlow B, DiScala C, et al: Efficacy of MAST use in children who present in hypotensive shock. J Trauma 1992;33:151.
   
3. Cayten CG, Berendt BM, Byrne DW, et al: A study of pneumatic antishock garments in severely hypotensive trauma patients. J Trauma 1993;34:728-735.
   
4. Flint L, Babikian G, Anders M, et al: Definitive control of hemorrhage from severe pelvic fracture. Ann Surg 1990;221:703-707.
   
5. O'Connor RE, Domeier RM: Collective review: An evaluation of the pneumatic anti-shock garment (PASG) in various clinical settings. Prehosp Emerg Care 1997;1:36-44.
   
6. Domeier RM, O'Connor RE, Delbridge TR, et al: Position paper: National Association of EMS Physicians: Use of the pneumatic anti-shock garment (PASG). Prehosp Emerg Care 1997;1:32-35.
   

Issued by:

Mark C. Henry, M.D.

Chairman, State Emergency Medical Advisory Committee

Authorized by:

Barbara A. DeBuono, M.D.

Commissioner, Department of Health

Revised: June 1998