ALM Resuscitation With Brain and Multiorgan Protection for Far-Forward Operations: Survival at Hypotensive Pressures

Area of Science:

• Trauma and hemorrhagic shock research
• Resuscitation strategies
• Pharmacological interventions

Background:

• Non-compressible torso hemorrhagic (NCTH) shock is a leading cause of potentially survivable battlefield trauma.
• Urgent need for novel hypotensive drug therapies to protect the heart and brain following NCTH.
• Permissive hypotension strategies require careful regulation of cardiac output and systemic vascular resistance.

Purpose of the Study:

• To examine the strengths and limitations of permissive hypotension.
• To discuss the development of small-volume adenosine, lidocaine, and Mg2+ (ALM) fluid resuscitation.
• To evaluate ALM therapy in preclinical models of NCTH.

Main Methods:

• Literature search on permissive hypotension (PubMed, Cochrane, Embase).
• Preclinical study in pigs undergoing liver resection and induced NCTH.
• Resuscitation with 3% NaCl ± ALM bolus and 0.9% NaCl ± ALM drip, followed by blood transfusion.
• Continuous monitoring of mean arterial pressure (MAP), cardiac output (CO), and systemic vascular resistance (SVR).

Main Results:

• Targeting a MAP of ~50 mmHg can be beneficial or harmful depending on CO and SVR regulation.
• ALM therapy in NCTH models induced a hypotensive, high-flow, vasodilatory state.
• Maintained tissue oxygen supply and neuroprotection were observed with ALM therapy.
• ALM therapy improved survival by resuscitating the heart, reducing internal bleeding, and decreasing secondary injury.

Conclusions:

• Small-volume ALM therapy resuscitates effectively at hypotensive pressures in NCTH models by increasing CO and reducing SVR.
• ALM therapy demonstrated heart and brain protection with maintained tissue oxygen delivery.
• Translational studies are needed to confirm reproducibility and optimize dosing.
• ALM therapy shows potential for prehospital and far-forward military applications.