Veno-arterial Carbon Dioxide Partial Pressure Difference (CO2gap) for Early Resuscitation of Sept… (NCT07179276) | Clinical Trial Compass
RecruitingNot Applicable
Veno-arterial Carbon Dioxide Partial Pressure Difference (CO2gap) for Early Resuscitation of Septic Shock
France750 participantsStarted 2026-03-29
Plain-language summary
Sepsis is a dysregulated host response to infection that leads to life-threatening organ dysfunction and represents a major healthcare problem. Septic shock is the most severe form, characterized by increased capillary permeability and vasodilation, resulting in hypotension and tissue hypoxia. Early identification and treatment of tissue hypoperfusion are pivotal components of initial resuscitation to limit progression to multiple organ dysfunction and death. The 2021 Surviving Sepsis Guidelines recommend guiding initial resuscitation by targeting decreases in serum lactate levels in patients with elevated lactate. However, although elevated lactate levels may reflect tissue hypoxia, serum lactate is not a direct marker of tissue perfusion. Hyperlactatemia may be attributable to mechanisms other than tissue hypoperfusion, such as accelerated aerobic glycolysis driven by excessive β-adrenergic stimulation or impaired clearance (e.g., in liver failure).
The venous-to-arterial carbon dioxide partial pressure difference (CO₂ gap), which is inversely related to cardiac output, has been shown to reflect the adequacy of venous blood flow to remove CO₂ from tissues. The CO₂ gap is closely linked to microcirculatory blood flow during the early resuscitation phase of septic shock and may effectively identify persistent tissue hypoperfusion in shock states. A persistently high CO₂ gap during early resuscitation has been associated with significantly higher 28-day mortality and increased Sequential Organ Failure Assessment (SOFA) scores. Moreover, the CO₂ gap has been shown to respond to changes in cardiac output during inotrope infusion in patients with low blood flow, suggesting that its assessment could be useful for therapeutic adjustments. Therefore, there are compelling arguments to evaluate the usefulness of the CO₂ gap in guiding early resuscitation in patients with septic shock.
The investigators postulated that CO₂ gap-guided early resuscitation may be more effective in improving outcomes than lactate-guided resuscitation.
Who can participate
Age range
18 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Patients aged 18 years or older AND
* Acutely admitted to a study ICU AND
* Primary diagnosis of septic shock according to the Sepsis-3 criteria and defined as:
* A suspected or documented site of infection or positive blood culture AND
* Acute increase of at least 2 points in the Sequential Organ Failure Assessment (SOFA) score consequent to the infection AND
* Having a serum lactate level \>2 mmol/l AND
* Requirement of vasopressors (any dose of norepinephrine) to maintain mean arterial pressure (MAP) ≥65 mmHg despite adequate fluid resuscitation (at least 1L of IV fluid in the last 24 hours prior to screening)
Exclusion Criteria:
* Septic shock for more than 12 hours at the time of screening
* Primary cause of hypotension not due to sepsis (e.g., acute bleeding)
* Decision not to resuscitate (or to limit full care) or not to intubate taken before obtaining consent
* Death is deemed to be imminent or inevitable or patients with an underlying disease process with a life expectancy of less than 3 months
* Anticipated surgery during the first 24 hours after randomization
* Patient or their relatives' refusal to participate
* Patients participating in another RCT with interventions possibly compromising the primary outcome
* Prior enrollment in the CARBON trial
* Known to be pregnant.
* Legal protection (i.e., incompetence to provide consent and no guardian or incarceration)
* No affiliation with the French health care system
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1This trial is using something called the CO2gap — the difference in carbon dioxide levels between venous and arterial blood — to guide resuscitation decisions in septic shock; can you explain what that measurement tells doctors about how well my organs are being perfused, and whether that approach might be relevant to my care?
2Since this trial is measuring all-cause mortality at 28 days as its main outcome, does that mean there isn't yet strong evidence that using CO2gap-guided resuscitation improves survival compared to standard care, and what does that uncertainty mean for me as a potential participant?
3Because the phase is listed as 'NA,' this appears to be a interventional strategy trial rather than a drug trial — can you walk me through exactly what would be done differently to my treatment if I were in the experimental group versus the control group, and what risks or burdens that might add?
4Septic shock requires fast, intensive treatment — given that I would need to be enrolled early in my ICU stay, how quickly would a decision about participation need to be made, and how does that affect my or my family's ability to give truly informed consent?
5Even if I don't join this trial, are there current standard-of-care resuscitation monitoring approaches that already incorporate CO2gap or similar measures, so I can understand whether I might benefit from this kind of monitoring regardless of trial enrollment?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
The primary end point is all-cause mortality at 28 days after randomization