Association between post-procedural hyperoxia and poor functional outcome after mechanical thrombectomy for ischemic...

Area of Science:

• Neurology
• Critical Care Medicine
• Cardiovascular Research

Background:

• The impact of oxygen therapy on stroke patients remains unclear, with ongoing debate regarding its routine use in emergency settings.
• Hyperoxia's effect on functional recovery in ischemic stroke patients undergoing intra-arterial mechanical thrombectomy (IAMT) requires investigation.

Purpose of the Study:

• To assess the association between hyperoxia (PaO2 > 120 mmHg) and functional recovery in ischemic stroke patients post-IAMT.
• To determine if elevated oxygen levels impact outcomes such as modified Rankin Scale (mRS) scores and mortality.

Main Methods:

• Prospective observational cohort study of adult ischemic stroke patients who underwent IAMT (2010-2015).
• Patients were mechanically ventilated and received supplementary oxygen aiming for saturation >94%.
• Groups were defined by admission partial pressure of oxygen (PaO2) with hyperoxia set at >120 mmHg; functional recovery assessed using mRS at 90 days.

Main Results:

• 333 patients included; higher PaO2 levels correlated with worse 90-day functional outcomes (higher mRS scores).
• Hyperoxia group showed significantly higher rates of mRS ≥ 4 (60.6%) and mRS ≥ 3 (70.6%) compared to the normoxia group (43.0% and 56.1%).
• Mortality was higher in the hyperoxia group (28.6% vs 18.7%); adjusted analysis confirmed poorer functional outcomes (OR 2.2.7 for mRS ≥ 4, OR 2.07 for mRS ≥ 3).

Conclusions:

• Admission hyperoxia (PaO2 > 120 mmHg) is associated with worse functional outcomes 90 days post-IAMT in ischemic stroke patients.
• The findings suggest a potential negative impact of excessive oxygenation on recovery after IAMT.
• Further research is necessary to validate these findings and elucidate the underlying mechanisms.