A comparative analysis of THAM (Tris-buffer) in traumatic brain oedema

Area of Science:

• Neuroscience
• Pharmacology
• Critical Care Medicine

Background:

• Brain edema and elevated intracranial pressure (ICP) are critical complications following severe head injury.
• Current treatments, including osmotherapy, have limitations in efficacy and duration.
• Investigating novel therapeutic agents for managing brain edema is crucial.

Purpose of the Study:

• To evaluate the efficacy of Tris hydroxymethyl aminomethane (THAM) in reducing brain edema and ICP.
• To compare THAM's effects with sodium bicarbonate in an animal model.
• To assess THAM's impact on ICP, cerebral perfusion pressure (CPP), and electroencephalogram (EEG) in head injury patients.

Main Methods:

• Animal studies involved cold brain lesions in rats, comparing THAM to sodium bicarbonate, measuring water and electrolyte content.
• Clinical study included 80 head injury patients randomized to receive THAM, mannitol, or sorbitol.
• Intracranial pressure (ICP), systemic arterial pressure (SAP), cerebral perfusion pressure (CPP), and EEG were monitored.

Main Results:

• THAM significantly reduced brain water and sodium content in rats, unlike bicarbonate, and preserved potassium levels.
• In patients, THAM rapidly decreased ICP, with a maximal reduction comparable to mannitol and sorbitol.
• THAM demonstrated a longer duration of ICP reduction and faster EEG improvement than osmotherapy, with no osmotic effects observed.

Conclusions:

• THAM shows significant efficacy in mitigating brain edema and reducing ICP in both experimental and clinical settings.
• THAM's mechanism appears to involve intracerebral buffering rather than osmotic effects.
• Further randomized clinical trials are warranted to confirm THAM's therapeutic potential in severe head injury.