During late sepsis, the lungs' ability to clear adrenomedullin from blood is dramatically reduced, contributing to the dangerous blood pressure collapse seen in advanced septic shock.
Clearance collapsesPulmonary adrenomedullin clearance drops dramatically in late sepsis, amplifying the vasodilatory peptide accumulation driving shock
What the researchers found
Pulmonary clearance of adrenomedullin was significantly reduced during late-stage sepsis in rats, contributing to ADM accumulation and the hemodynamic collapse of septic shock.
Why it matters
Septic shock kills millions annually. Understanding that the lungs fail to clear vasodilatory peptides during late sepsis provides a new therapeutic target — restoring ADM clearance or blocking excess ADM could prevent fatal blood pressure collapse.
How the study worked
Animal study using a rat polymicrobial sepsis model. Adrenomedullin levels and pulmonary clearance were measured during early (hyperdynamic) and late (hypodynamic) phases of sepsis.
What this study cannot tell us
Rat sepsis model may not perfectly replicate human sepsis. The exact mechanism of reduced pulmonary clearance was not identified. Single peptide focus may miss interactions with other vasoactive mediators.
How to read the evidence
Preliminary animal evidence from a controlled sepsis model with clear hemodynamic and pharmacokinetic data.
When this study was published
Published in 1999. Adrenomedullin's role in sepsis has been confirmed, and MR-proADM is now used clinically as a sepsis biomarker.
The bigger picture
Septic shock involves cascading organ failures. The finding that lung dysfunction contributes to peptide hormone accumulation reveals how organ failures compound each other — a failing lung can't clear vasodilatory peptides, worsening cardiovascular collapse.
Questions still open
- Could ADM receptor antagonists help prevent late-sepsis hemodynamic collapse?
- Is reduced pulmonary peptide clearance a general phenomenon in organ failure?
- Can pulmonary ADM clearance be pharmacologically restored?
Common questions
What happens to blood pressure in sepsis?
Why do the lungs matter in sepsis?
Read the original research
Pulmonary clearance of adrenomedullin is reduced during the late stage of sepsis.
Biochimica et biophysica acta, 1427(2), 315-21
Citation
Ornan, D A; Chaudry, I H; Wang, P. (1999). Pulmonary clearance of adrenomedullin is reduced during the late stage of sepsis.. Biochimica et biophysica acta, 1427(2), 315-21.