ICP changes following application of the MAST suit

Area of Science:

• Trauma Care
• Emergency Medicine
• Physiology

Background:

• The Military Anti-Shock Trouser (MAST) suit is utilized to manage hemorrhagic shock by increasing arterial pressure.
• Concerns exist regarding MAST suit application in patients with closed head injury, cardiac tamponade, or tension pneumothorax due to increased venous return.

Purpose of the Study:

• To evaluate the physiological effects of the MAST suit in dogs under conditions of hemorrhage, tension pneumothorax, cardiac tamponade, and intracranial lesions.
• To assess the impact of MAST suit inflation on systemic arterial pressure, central venous pressure, pulmonary artery pressure, and intracranial pressure.

Main Methods:

• Hemorrhage was induced in canine models.
• Simulated conditions of tension pneumothorax, cardiac tamponade, and mass intracranial lesion were created.
• Hemodynamic parameters including pulmonary artery, central venous, systemic arterial, and intracranial pressures were continuously monitored before and after MAST suit application.

Main Results:

• MAST suit inflation significantly increased systolic arterial pressure, central venous pressure, pulmonary artery pressure, and intracranial pressure following hemorrhage.
• Intracranial pressure increases were proportional to central venous pressure increases and did not reach harmful levels in hemorrhaged animals or those with intracranial lesions.
• In cases of cardiac tamponade and tension pneumothorax, MAST suit inflation caused a substantial rise in central venous and intracranial pressures, which could be mitigated by addressing the underlying condition or reducing suit pressure.

Conclusions:

• The MAST suit can be safely applied in patients with hemorrhagic shock, even in the presence of head injury or intracranial lesions.
• Careful consideration and potential modification of pressure are advised when using the MAST suit in patients with cardiac tamponade or tension pneumothorax.
• The study demonstrates the MAST suit's efficacy in managing hemorrhagic shock while providing insights into its effects in complex trauma scenarios.