Intermittent hemodialysis yields the highest baclofen elimination among 5 extracorporeal devices in equine whole blood ex vivo.

OBJECTIVE

To compare baclofen removal by 5 devices across 3 modalities-intermittent hemodialysis (IHD) with low- and high-efficiency dialyzers, prolonged intermittent renal replacement therapy (PIRRT), and 2 hemoperfusion (HP) devices-in ex vivo equine blood. We hypothesized that IHD would be the most effective in baclofen elimination.

METHODS

Heparinized equine whole blood was spiked with reference baclofen and treated with low-efficiency IHD, high-efficiency IHD, PIRRT, carbon HP, polymer HP, and control. Each modality ran for 2 hours, targeting 20 times the assigned blood volume. Plasma baclofen was measured by UPLC-MS-MS at baseline and every 20 minutes. Elimination rate constants (k), reduction ratios, and extraction ratios were calculated from duplicate runs from April 29 through May 2, 2026.

RESULTS

Baclofen was eliminated the fastest by IHD (k, almost equal to 2.7 h-1 for both dialyzers; half-life, almost equal to 15 minutes), then PIRRT (k, 2.3 h-1), and most slowly by HP (1.7 and 1.3 h-1 for carbon HP and polymer HP). Between-run variability was lowest for PIRRT (coefficient of variation, 6%) and highest for carbon HP (coefficient of variation, 77%). Reduction ratios were 99.4% (both IHD), 98.9% (PIRRT), 92.7% (polymer HP), and 89.2% (carbon HP).

CONCLUSIONS

All modalities substantially reduced baclofen in equine blood ex vivo. Based on the elimination rate constant, IHD was the most effective modality for baclofen elimination.

CLINICAL RELEVANCE: Intermittent hemodialysis achieves the most rapid removal. In vivo studies are warranted to compare the performance and efficacy of each modality across clinical settings.