Daily Sepsis Research Analysis
Analyzed 11 papers and selected 3 impactful papers.
Summary
Today’s strongest sepsis-related evidence includes a multicenter cohort showing that early arterial pH deterioration independently predicts 28-day mortality, a translational study identifying rhapontigenin as a potential therapy for sepsis-associated acute kidney injury through ferroptosis and NF-κB modulation, and a neonatal randomized trial finding no significant difference between norepinephrine and dopamine for initial septic shock treatment. Together, these studies advance early risk stratification, mechanistic therapeutic development, and evidence-based neonatal hemodynamic management.
Research Themes
- Early physiological risk stratification in sepsis
- Mechanisms and therapeutic targets in sepsis-associated organ injury
- Comparative vasoactive therapy in neonatal septic shock
Selected Articles
1. Early Arterial pH Changes as Strong Predictors of Mortality in Sepsis: A Multicenter Cohort Study.
In 3,512 patients with community-acquired sepsis, early arterial pH change from the emergency department to the ICU showed a nonlinear association with 28-day mortality. In an independent validation cohort, pH declines below baseline-specific thresholds predicted mortality, with an overall adjusted hazard ratio of 2.80 and the strongest association among patients with initially normal pH.
Impact: This study offers a readily available, dynamic physiological marker that may identify acute deterioration even when the initial pH appears normal. The derivation-and-validation design strengthens its potential for incorporation into early sepsis risk stratification, although prospective clinical utility testing remains necessary.
Clinical Implications: Serial arterial blood gas assessment during the emergency department-to-ICU transition may improve recognition of patients at high risk for early death. ΔpH should be considered an adjunct to, rather than a replacement for, established severity scores and clinical assessment.
Key Findings
- The study included 3,512 patients with community-acquired sepsis admitted to the ICU within 6 hours of emergency department presentation.
- Greater early pH deviations, particularly declines, were associated with increased 28-day mortality across baseline acidosis, normal pH, and alkalosis groups.
- In the validation cohort, ΔpH below the predefined thresholds predicted mortality overall with an adjusted hazard ratio of 2.80; the hazard ratio was 4.43 among patients with initially normal pH.
Methodological Strengths
- Large multicenter cohort with 3,512 patients and clinically relevant 28-day mortality outcome.
- Use of restricted cubic splines to assess nonlinear associations and an independent derivation-validation framework for prognostic cutoffs.
Limitations
- The retrospective observational design limits causal inference and may be affected by residual confounding.
- The cohort consisted of community-acquired sepsis patients admitted to the ICU, which may limit generalizability to hospital-acquired sepsis or patients not requiring intensive care.
Future Directions: Prospective multicenter studies should test whether integrating ΔpH into existing early warning or sepsis severity scores improves clinical decisions and patient outcomes. Research should also examine whether targeted correction of the physiological processes underlying pH deterioration changes prognosis.
PURPOSE: To evaluate the prognostic significance of early arterial pH changes (ΔpH) during the transition from the emergency department (ED) to the intensive care unit (ICU) in patients with sepsis. METHODS: This multicenter retrospective cohort study included 3,512 patients with community-acquired sepsis admitted to the ICU within 6 h of ED presentation between September 2019 and December 2023. The patients were stratified by baseline pH into acidosis (<7.35), normal (7.35-7.45), and alkalosis (>7.45). ΔpH was defined as the difference between ED pH and the lowest ICU pH within 24 h after ICU admission.
2. Rhapontigenin Alleviates Sepsis-Associated Acute Kidney Injury and Is Accompanied by Modulation of Ferroptosis, Inflammation, and NF-κB Signaling.
Rhapontigenin protected LPS-stimulated HK-2 cells and cecal ligation and puncture mice from experimental sepsis-associated acute kidney injury. Its effects were accompanied by reduced intracellular iron, reactive oxygen species, lipid peroxidation, inflammatory cytokines, and NF-κB activation, together with preservation of GPX4 and xCT expression.
Impact: The study links ferroptosis and NF-κB-dependent inflammation in sepsis-associated kidney injury and identifies rhapontigenin as a potential pharmacological candidate. The mechanistic evidence spans cell culture and an in vivo sepsis model, but translation to human treatment remains preliminary.
Clinical Implications: Rhapontigenin or related pathway-directed therapies may eventually provide adjunctive treatment for sepsis-associated acute kidney injury. The findings are not sufficient to support clinical use, and pharmacokinetics, safety, dosing, and efficacy in clinically relevant infection models must be established first.
Key Findings
- Rhapontigenin at 20-40 μM improved viability of LPS-treated HK-2 cells and reduced intracellular Fe2+, reactive oxygen species, malondialdehyde, and lipid reactive oxygen species.
- Rhapontigenin increased GPX4 and xCT expression and reduced inflammatory cytokines and NF-κB phosphorylation with decreased p65 nuclear localization.
- In cecal ligation and puncture mice, rhapontigenin reduced serum NGAL, KIM-1, creatinine, BUN, renal iron, malondialdehyde, and inflammatory cytokines; kidney injury scores were significantly reduced at 50 mg/kg.
Methodological Strengths
- Mechanistic assessment included multiple ferroptosis-related readouts, inflammatory mediators, and NF-κB signaling measures.
- The findings were evaluated in both an in vitro cellular model and an in vivo cecal ligation and puncture model, with pharmacological pathway perturbation using erastin, ferrostatin-1, and RANKL.
Limitations
- The study used LPS-stimulated HK-2 cells and a murine cecal ligation and puncture model, which may not reproduce the heterogeneity of human sepsis-associated acute kidney injury.
- No clinical pharmacokinetic, toxicity, pathogen-clearance, or survival data were reported, and the direct causal contribution of ferroptosis relative to other injury pathways remains incompletely established.
Future Directions: Future studies should assess rhapontigenin in clinically relevant polymicrobial infection models, determine dose-exposure relationships and safety, and evaluate effects on survival, pathogen clearance, and renal recovery. Confirmation using genetic ferroptosis models and human kidney or organoid systems would strengthen causal inference.
Sepsis-associated acute kidney injury (SA-AKI) is a common complication in critically ill patients and is associated with high mortality. Evidence suggests that ferroptosis-related lipid peroxidation and inflammatory responses contribute to renal injury. The potential effects of rhapontigenin (Rha), a natural compound with antioxidant and anti-inflammatory properties, have not been directly examined in SA-AKI. HK-2 cells were pretreated with Rha for 3 h, followed by stimulation with 10 ng/mL LPS for 24 h to establish an in vitro sepsis-associated injury model. Cell viability was assessed by CCK-8. Ferroptosis-related changes were evaluated by measuring GPX4 and xCT expression, intracellular Fe2+, ROS, MDA, and BODIPY-C11-detected lipid ROS.
3. Norepinephrine Versus Dopamine as Initial Vasoactive Therapy in Neonatal Septic Shock: A Randomized Controlled Trial in a Tertiary Care Neonatal Intensive Care Unit in Eastern India.
In this non-blinded randomized trial of 90 neonates with septic shock, norepinephrine and dopamine had similar rates of shock reversal within 45 minutes. There were also no significant differences in additional vasoactive support, mechanical ventilation, 28-day mortality, or short-term complications, providing clinically relevant negative comparative evidence.
Impact: The trial directly addresses a common neonatal intensive care decision and challenges the assumption that norepinephrine is clearly superior to dopamine in neonatal septic shock. Although underpowered for definitive mortality conclusions, its neutral findings are valuable for guiding future adequately powered trials and preventing premature therapeutic preference.
Clinical Implications: Both norepinephrine and dopamine may be considered initial vasoactive agents for neonatal septic shock when selected according to local expertise, hemodynamic phenotype, drug availability, and monitoring capacity. The findings do not establish equivalence for mortality or rare complications and should not replace individualized care.
Key Findings
- Ninety neonates with septic shock were randomized equally to norepinephrine or dopamine in a non-blinded parallel trial.
- Shock reversal within 45 minutes occurred in 31.1% of the norepinephrine group and 35.5% of the dopamine group, with no significant difference.
- Mortality was comparable between groups at 15.5% for norepinephrine and 13.3% for dopamine, and rates of mechanical ventilation and intraventricular hemorrhage, bronchopulmonary dysplasia, necrotizing enterocolitis, and retinopathy of prematurity were also similar.
Methodological Strengths
- Randomized parallel-group allocation directly compared two commonly used vasoactive agents in neonatal septic shock.
- The study assessed early hemodynamic response, mortality, need for additional support, and multiple clinically relevant neonatal complications.
Limitations
- The trial was non-blinded, single-center, and small, limiting protection against bias and statistical power for mortality and uncommon complications.
- The fixed initial dosing strategies and single tertiary-care setting may limit generalizability to different neonatal populations, gestational ages, and treatment protocols.
Future Directions: Larger multicenter, preferably blinded or protocol-standardized trials should stratify patients by gestational age, myocardial function, vascular tone, and infection phenotype. Trials should be powered for mortality, neurodevelopmental outcomes, organ dysfunction, and treatment-related adverse events.
Background Septic shock remains a major cause of neonatal morbidity and mortality, particularly in preterm and low birth weight neonates. Although dopamine was traditionally used as the first-line vasoactive agent in neonatal shock, norepinephrine has emerged as a potential alternative agent of late because of its potent vasoconstrictive effects and favourable hemodynamic profile. However, evidence comparing the efficacy of these agents in septic shock in neonates remains limited. Objective To compare the efficacy of norepinephrine and dopamine as the initial vasopressor in neonatal septic shock. Methods This study was a non-blinded parallel randomized controlled trial conducted between October 2020 and October 2022 in the neonatal intensive care unit of a tertiary care center in Odisha, India. Ninety neonates with septic shock were randomized into two groups.