The polymyxin-B direct hemoperfusion OPTimal Initiation timing with Catecholamine PMX-OPTIC study: A multicenter...

Area of Science:

• Critical Care Medicine
• Nephrology
• Pharmacology

Background:

• Polymyxin-B direct hemoperfusion (PMX-DHP) is an endotoxin adsorption therapy used for septic shock.
• Its blood pressure elevating effects suggest optimal efficacy when initiated during peak vasopressor support.
• This timing may be key to reducing mortality in severe sepsis.

Purpose of the Study:

• To investigate the association between the timing of PMX-DHP initiation relative to peak vasopressor dose and 28-day mortality in septic shock patients.
• To identify optimal timing strategies for PMX-DHP to improve survival rates.

Main Methods:

• A multicenter retrospective study analyzed 480 septic shock patients across 24 ICUs in Japan.
• The time interval between peak vasopressor dose (noradrenaline equivalent, NEq) and PMX-DHP initiation was evaluated.
• Multivariable analysis assessed factors associated with 28-day mortality.

Main Results:

• Patients who died were older, more severely ill, and had higher BMI, peak NEq, and NEq at PMX-DHP initiation.
• Initiating PMX-DHP within 4 hours before or after the NEq peak (-4h << 4h) was associated with higher survival rates (75.3%) compared to earlier (≤-4h) or later (≥4h) initiation.
• Multivariable analysis showed significantly higher odds of mortality when PMX-DHP was initiated outside the -4h to 4h window around the NEq peak.

Conclusions:

• Initiating PMX-DHP therapy at the time of peak vasopressor dose correlates with reduced 28-day mortality in septic shock.
• Both early and late initiation of PMX-DHP relative to the vasopressor peak may not improve patient outcomes.
• PMX-DHP timing is a critical factor in managing septic shock and potentially improving survival.