Septic Shock / Capillary refill time (CRT) / Oxygen extraction ratio (O₂ER) assessment · Observational Study

Discordance Between Capillary Refill Time and Oxygen Extraction Ratio in Septic Shock

ClinicalTrials.gov · August 19, 2026

Preliminary Why this matters to you Expert discussion

Early or partial results. Treat as a signal, not a conclusion.

AI Summary

This is a registered prospective observational study investigating the prevalence and mortality association of discordant capillary refill time and oxygen extraction ratio phenotypes in septic shock. No results are yet reported in this registry record; the study is actively recruiting.

What was studied

Observational. Septic Shock, Sepsis; age from 18 Years. Intervention: septic schoc cohort. n = 100. 1 site: Turkey (Türkiye).

Key findings

Safety

Safety was not reported in the material analysed. Check the source before drawing any conclusion about harm.

Who this may help

If completed and published, this study may clarify whether discordance between macrocirculatory and microcirculatory markers predicts mortality and warrants targeted resuscitation strategies in septic shock. At present, no clinical guidance can be drawn from this registry entry alone.

Plain-language summary

This is an ongoing observational registry study with no results posted; it aims to characterize a diagnostic phenotype and its association with mortality in septic shock, but enrollment and outcome data are not yet reported.

Study design

As stated by the source record.

MethodsCohort model. Prospective time perspective. Primary outcome measures: Prevalence of the discordant CRT-O₂ER phenotype (assessed at At hour 6 of resuscitation (6 hours after vasopressor initiation)); 28-day all-cause mortality (assessed at 28 days from Hour 0 (vasopressor initiation))

DesignObservational

PopulationSeptic Shock, Sepsis; age from 18 Years

Sample size100

Interventionseptic schoc cohort

Setting1 site: Turkey (Türkiye)

Reported figures

Quoted from the source exactly as published.

Planned sample size100

Primary outcome measure 1Prevalence of discordant CRT-O₂ER phenotype at hour 6 of resuscitation

Primary outcome measure 228-day all-cause mortality from Hour 0 (vasopressor initiation)

Clinical bottom line

Caveats

Results are not yet reported in this registry record; study is actively recruiting.
Single-center design; generalizability to other populations and settings unknown.
No power calculation or statistical analysis plan reported in registry record.
Selection bias inherent to observational design; no adjustment for confounders described.

Evidence assessment

Graded across the dimensions that decide whether you should act, each from what the source actually supports. There is no single score, and where a dimension was not assessed it says so.

Study design

moderate

Prospective single-center observational cohort; no randomization or control arm.

Directness

strong

Direct assessment of clinical phenotype and 28-day mortality in septic shock population.

Consistency

insufficient

No results reported; consistency cannot be assessed from registry record alone.

Risk of bias

limited

Single center, observational design; no blinding. Selection bias and confounding possible.

Sample adequacy

limited

Estimated enrollment 100 participants; no power calculation reported in registry record.

What is missing. This record has no key findings. That is a gap in the analysis, not a judgement about the study.

Source abstract

Registry record from ClinicalTrials.gov (NCT07774962). This is a study registration, not published results. Lead sponsor: Istanbul University - Cerrahpasa. Recruitment status: RECRUITING. Study type: OBSERVATIONAL. Enrollment: 100 participants (ESTIMATED). Conditions: Septic Shock, Sepsis. Interventions: DIAGNOSTIC_TEST: Capillary refill time (CRT); DIAGNOSTIC_TEST: Oxygen extraction ratio (O₂ER) assessment. Primary outcome measures: Prevalence of the discordant CRT-O₂ER phenotype , At hour 6 of resuscitation (6 hours after vasopressor initiation); 28-day all-cause mortality , 28 days from Hour 0 (vasopressor initiation). Brief summary: In septic shock, restoring large-vessel (macrocirculatory) perfusion-reflected by a normal capillary refill time (CRT)-does not always mean that oxygen use at the tissue level has recovered. This mismatch, sometimes called loss of hemodynamic coherence, may be detectable by comparing CRT with the oxygen extraction ratio (O₂ER), a marker of how much oxygen the tissues are extracting from the blood. Patients whose CRT has normalized but whose O₂ER remains abnormal-either too high (suggesting oxygen delivery that is insufficient for demand) or too low (suggesting microcirculatory shunting)-are considered to have a "discordant" perfusion phenotype. This prospective, single-center, observational cohort study aims to determine how often this CRT-O₂ER discordance occurs at the 6th hour of resuscitation in adult patients with septic shock, and whether it is associated with 28-day mortality. Approximately 100 consecutive adult patients diagnosed with septic shock (with pre-existing central venous and arterial catheters) will be followed. Clinical and laboratory measurements-including CRT, O₂ER, lactate, mottling score, and organ dysfunction scores-will be recorded at hours 0, 6, 12, and 24, with the main phenotype grouping performed at hour 6. The study is purely observational: CRT is a painless, non-invasive bedside measurement, and O₂ER is calculated from blood gas samples already drawn as part of routine care, so no additional interventions or blood draws are performed for research purposes.

Follow from this

Taken from the source record, never inferred. Follow any of these and new work involving them reaches your briefing.

Septic ShockCapillary refill time (CRT)Oxygen extraction ratio (O₂ER) assessmentIstanbul University - CerrahpaNCT07774962Sepsis