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Published on: September 27, 2024
Methylene blue attenuates lung injury after mesenteric artery clamping/unclamping
1Post-Anaesthesia Care Unit, Animal Research Laboratory, Tel Aviv Sourasky Medical Center and the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel. draviw@tasmc.health.gov.il
Background:
This controlled, experimental study was designed to assess the effects of intratracheal and intravenous methylene blue on reperfusion lung injury following superior mesenteric artery clamping/unclamping.
Materials And Methods:
Superior mesenteric arteries of 144 anaesthetized adult male Wistar rats (n = 12/group) were clamped for 1 h. Ten minutes before unclamping, methylene blue or its vehicle was administered intratracheally or intravenously, followed by a 3 h-respiratory assessment and postexperimental assessment of survival.
Results:
Intravenous 3 and 9 mg kg(-1) but not higher methylene blue doses, and intratracheal 6-mg kg(-1) but not lower doses, significantly (P < 0.05) reduced the 100% increase in plateau pressure, 30% reduction in PO(2)/FiO(2), fourfold augmented bronchoalveolar lavage-retrieved volume and the increased polymorphonuclear leukocytes/bronchoalveolar cells' ratio associated with unclamping of the superior mesenteric artery. Lung tissue polymorphonuclear leukocytes count, total xanthine oxidase activity and wet-to-dry-weight ratio were also normal in these dose-treated groups. These effective regimens were also associated with longer animal survival.
Conclusions:
Intratracheal methylene blue mitigates lung reperfusion injury following superior mesenteric artery clamping/unclamping at a similar magnitude as an intravenous regimen. This finding is a novel potential use of methylene blue in vivo.
Insights
Methylene blue administered intratracheally or intravenously effectively reduces lung reperfusion injury after mesenteric artery clamping in rats, improving respiratory function and survival.
Area of Science:
- Physiology
- Pharmacology
- Surgical Research
Background:
- Reperfusion lung injury is a significant complication following mesenteric artery clamping.
- Methylene blue is investigated for its potential therapeutic effects.
Purpose of the Study:
- To evaluate the efficacy of intratracheal and intravenous methylene blue in mitigating lung reperfusion injury.
- To assess the impact on respiratory parameters and survival rates.
Main Methods:
- A controlled experimental study using Wistar rats subjected to superior mesenteric artery clamping.
- Administration of methylene blue via intratracheal or intravenous routes before reperfusion.
- Assessment of respiratory function, lung injury markers, and survival.
Main Results:
- Specific doses of intravenous (3 and 9 mg/kg) and intratracheal (6 mg/kg) methylene blue significantly reduced lung injury markers.
- Effective doses normalized plateau pressure, improved PO(2)/FiO(2) ratio, and decreased inflammatory cell infiltration.
- Treatment with effective methylene blue regimens was associated with increased animal survival.
Conclusions:
- Intratracheal methylene blue demonstrates comparable efficacy to intravenous administration in mitigating lung reperfusion injury.
- This study presents a novel potential in vivo application for intratracheal methylene blue.
