Evaluating the Use of Thromboelastography (TEG) in Patient's Requiring Extracorporeal Membrane Oxygenation (ECMO): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Evaluating the Use of Thromboelastography (TEG) in Patient's Requiring Extracorporeal Membrane Oxygenation (ECMO) (NCT02887820), a na na study. The primary outcome is Number of Participants Whose Blood Management Care Follows a TEG Algorithm 90% of the Time.

2. Clinical Question

The study asks whether a thromboelastography (TEG) algorithm can be used alongside traditional laboratory testing to guide transfusion and coagulation management in patients requiring extracorporeal membrane oxygenation (ECMO). The registry describes the study as a pilot focused on feasibility and safety, rather than as a comparison of treatments.

The question is about whether a care process was followed, not whether TEG changed a clinical outcome relative to another approach. The registry also lists outcomes involving transfusions, bleeding or thrombotic-related adverse events, blood loss, exchanges and circuit clotting. Results for the primary endpoint and these additional outcomes are not reported in the registry record.

3. Trial Design

The registry describes NCT02887820 as a pilot study of point-of-care testing with TEG for blood product transfusion in patients requiring ECMO. Its stated aim is to evaluate feasibility and safety when a TEG algorithm is used alongside traditional laboratory tests. The design is single-group; the allocation entry is NA and masking is listed as none. Phase is listed as NA.

All subjects are described as belonging to the pilot group. The arm description names traditional coagulation and transfusion tests, including arterial blood gas, complete blood count, fibrinogen, platelet count, aPTT, PT, anti-Xa and ACT, as well as TEG. The arm-description text is incomplete in the registry record, so further details of testing or decision rules are not reported there.

Enrollment is recorded as 15. The study start is 2017-12-15 and primary completion is recorded as 2023-12-31. The status is terminated. The reason for termination is not reported in the registry record. Stephen Esper is listed as sponsor.

Because there is no separate control group, the design can describe experience within the pilot group but cannot directly estimate a difference between TEG-guided care and another management strategy. The registry lists 12 outcome measures, including the primary measure and outcomes related to transfusions, bleeding or thrombotic events, blood loss, blood products, pump or oxygenator exchanges, and clotting. No analysis entries are listed, and outcome results are not reported in the registry record.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants Whose Blood Management Care Follows a TEG Algorithm 90% of the Time, measured over From time patient is placed on ECMO to 30-days post ECMO initiation.

The primary endpoint counts participants whose blood management care follows a TEG algorithm 90% of the time. Its stated observation period runs from the time a patient is placed on ECMO to 30-days post ECMO initiation. The endpoint is expressed as a count of participants, rather than as a treatment contrast or a measure of change from baseline.

This kind of endpoint is relevant to a feasibility study because it focuses on whether the intended care process was followed. It does not, by itself, describe the clinical effect of that process. A participant meeting the adherence criterion would contribute to the endpoint count, but the registry does not report how many participants met it. The precise operational definition of following the algorithm, including how opportunities for adherence were identified and how the 90% threshold was assessed, is not reported in the registry record.

Interpreting a count requires knowing both the count and the population to which it refers. The registry records enrollment of 15, but does not report a primary endpoint result, an analysis population, or how missing adherence information was handled. Consequently, the endpoint’s observed value and its precision cannot be assessed from the registry record. The listed endpoint is a measure of process feasibility; it is not evidence of benefit or harm compared with another strategy.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

General explanation. A pilot study often examines whether a proposed process can be carried out and whether relevant outcomes can be collected. Such a study can inform questions about implementation and measurement. Its design and amount of information may not support precise estimates of clinical effects. In this trial, the stated focus is feasibility and safety, and the primary endpoint concerns adherence to a TEG algorithm.

What does a single-group design show?

The registry lists a single-group model, with no separate control arm. In a single-group study, outcome data describe the participants who received the study approach. Without a concurrent comparison group, the observed course cannot establish what would have happened under another management strategy. Changes or events may reflect the underlying clinical setting, other care, or the study approach; the design does not isolate those possibilities.

Allocation is listed as NA and masking as none. These entries do not describe a randomized comparison. There is consequently no basis in the registry record for a between-group treatment estimate. Descriptive counts may still be useful for understanding what was recorded, but they answer a different question from a comparative estimate.

How should the primary endpoint be understood?

The endpoint is a count of participants whose care follows the TEG algorithm 90% of the time during the stated period. It is a participant-level process measure. It is not a count of transfusions, a laboratory value, or a direct clinical outcome. The threshold gives the process measure a stated criterion, but the registry does not define the calculation of adherence in enough detail to determine how opportunities, exceptions or incomplete records would be treated.

General explanation. A confidence interval expresses the uncertainty around an estimate under the assumptions of the statistical method used. A narrow interval indicates greater precision than a wide interval, while neither interval alone establishes that a result is clinically important. No interval or endpoint estimate is reported in the registry record, so precision cannot be assessed for the primary endpoint.

What can safety counts tell readers?

Counts of participants affected by adverse events are descriptive unless accompanied by additional design and analysis information. Their interpretation depends on who was observed, how long observation continued, how events were defined and how completely events were captured. The registry provides at-risk and affected counts, plus a death count, but does not report the event-level detail or analysis needed to establish causes or compare risk across strategies.

General explanation. When event counts are sparse, estimates can be imprecise, and methods that rely on large-sample approximations may not perform well. The registry record does not list an inferential analysis for the safety counts. No claim about the statistical precision of these counts can therefore be made from the posted information.

What is the role of the sample-size illustration?

The planning illustration is explicitly separate from the trial’s own design. Its stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and detection of a stated fraction of the observed effect. For time-to-event tables, it gives a total number of events; for other tables, it gives participants per arm.

Those assumptions do not describe this single-group pilot’s design, which has no two-arm allocation. A planning illustration is not an observed study result and is not observed power. It cannot fill in the missing primary endpoint estimate or establish what the trial found. The record does not report the trial’s own sample-size justification. The numerical outputs of the planning illustration are not described in the registry record.

Why do missing data and analysis choices matter?

General explanation. When endpoint data are unavailable for some participants, the result can depend on whether missing observations are excluded, treated as failures, or addressed through a model or other prespecified method. These choices can affect both the estimate and its uncertainty. The registry record does not report the primary endpoint analysis population or a missing-data method. It is therefore not possible to determine how incomplete follow-up or absent adherence information would affect an estimate.

The registry lists 12 outcome measures but no analysis entries. It does not report a statistical analysis plan, multiplicity adjustment, interim analyses or model specifications. Those details should not be inferred. In general, when many outcomes are examined, the chance of observing an apparently notable result among them can increase; methods for addressing that issue depend on the planned analyses. No such method is reported.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Pilot Arm")
n      <- c(15)
events <- c(4)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Pilot Arm  15  4  26.7  7.8  55.1  10.9  52.0  11.0  52.4

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 12 outcome measures, covering the primary adherence count and additional measures related to transfusion requirements, adverse events, blood loss, transfusion timing and products, exchanges, and circuit clotting. Considering multiple outcomes can create a multiplicity issue: if many statistical tests are conducted, the overall chance of at least one apparently notable finding may be greater than for a single test. This is a general statistical consideration, not a reported finding from this study.

A multiplicity strategy might specify which endpoint is primary, which outcomes are exploratory, and whether any adjustment or hierarchy will be used. The registry identifies a primary endpoint, but a multiplicity procedure is not reported in the registry record. No analysis entries are listed, so it is not possible to tell which outcomes were analyzed or how any tests were interpreted.

The record does not report the analysis population for the primary endpoint or the other outcomes. It also does not report how participants with incomplete follow-up, missing laboratory measurements, or unavailable adherence information were handled. These omissions matter because the outcome count and its interpretation can depend on which observations are included. The registry does not provide enough information to judge whether missingness could have affected results.

Interim analyses and a detailed statistical analysis plan are not reported in the registry record. Their absence from the record should not be replaced by assumptions about whether they occurred. Without the analysis population, missing-data approach, and multiplicity plan, readers cannot assess the analytic choices that would be needed to interpret a set of endpoint results. No endpoint results are reported in any case.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry’s Pilot Arm safety listing records 15 participants at risk for serious adverse events and 0 affected. It separately records 15 at risk for other adverse events and 0 affected. The listing also records 3 deaths. These figures should be read as registry counts, not as a comparison between treatment strategies.

The record does not report the causes or timing of the deaths, whether they were considered related to the device or care approach, or how they relate to the adverse-event counts. It also does not report detailed event definitions, duration of safety follow-up, or event-level descriptions; no top serious-event terms are listed. The counts therefore do not establish causation or provide a complete characterization of safety.

General explanation. A zero count in a limited dataset does not prove that an event cannot occur. The ability to interpret a zero count depends on the size and follow-up of the observed population, how events were sought and recorded, and the precision of the estimate. No precision estimate or comparative safety analysis is reported in the registry record.

13. What the Result Does, and Does Not, Mean

The study’s primary question concerns whether blood management care follows a TEG algorithm 90% of the time during the stated ECMO period. That is a process and feasibility question. The registry record identifies the endpoint but does not report its observed count, so it does not show how often the adherence criterion was met.

The design is single-group, with allocation listed as NA and no comparator arm. The registry therefore does not provide a direct comparison of TEG-guided management with another strategy. The listed outcomes involving transfusions, bleeding or thrombotic events, blood loss, exchanges and circuit clotting could describe the pilot experience, but their results are not reported in the registry record.

The safety listing includes zero affected participants for both serious and other adverse events, alongside 3 deaths. The record does not explain the relationship between those counts or report causes and attribution. These figures should not be treated as proof that the approach caused or prevented any event.

The study is terminated, and the reason is not reported in the registry record. No statistical analyses are listed. As a result, the record cannot support conclusions about the observed feasibility result, the precision of any estimate, or the clinical effect of TEG-guided management. The findings needed to answer those questions are not reported in the registry record.

14. Why This Trial Matters Statistically

This trial is statistically relevant because it frames TEG use as an implementation question in a complex clinical setting. The primary endpoint is about adherence to a defined algorithm, rather than a comparison of clinical outcomes. Separating process measures from outcome measures helps readers understand what a pilot can address and what would require a comparative design.

The single-group structure also illustrates an important limit of descriptive evidence. Counts observed among participants can characterize the recorded pilot experience, but without a comparator they do not identify what outcomes would have occurred under a different approach. This distinction is important for interpreting the registry’s listed measures of transfusion, bleeding, thrombosis and circuit-related events.

The record also illustrates why reporting the endpoint estimate, analysis population, missing-data handling and uncertainty is important. The primary endpoint is specified, but its result and analysis are not reported. Without those details, readers cannot evaluate either the observed adherence level or how precisely it was estimated. A terminated status and recorded safety counts likewise need context, including event definitions and follow-up.

Finally, the separate planning illustration should not be mistaken for a description of this trial’s design or its observed evidence. Planning assumptions and calculations can help frame future study design, but they do not substitute for outcome results. The registry record makes the feasibility question identifiable while leaving the statistical evidence needed to answer it unreported.

15. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The central limitation for interpretation is that the primary endpoint result is not reported in the registry record. The record also lists no analysis entries, so there is no reported estimate or uncertainty measure for the adherence endpoint or the other outcomes. Enrollment is recorded as 15, but the analysis population and outcome-specific participant counts are not reported.

The single-group design has no like-for-like control comparison. This limits conclusions about differences attributable to the TEG algorithm. Allocation is listed as NA and masking as none. The registry does not report a statistical analysis plan, missing-data methods, multiplicity procedures, or interim analyses.

The study status is terminated, but the reason for termination is not reported. Primary completion is recorded as 2023-12-31; the record does not establish whether all planned follow-up was completed. The arm description is incomplete, and further operational detail about the algorithm, adherence assessment and outcome definitions is not reported. The safety counts lack reported causes, attribution, event-level detail and follow-up context. These limitations constrain interpretation of both feasibility and safety.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Evaluating the Use of Thromboelastography (TEG) in Patient's Requiring Extracorporeal Membrane Oxygenation (ECMO) — NCT02887820.
• Registry record last updated 2025-05-31; status last verified 2025-05.
• Results first posted 2025-05-31.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

19. Record Summary

NCT02887820 is a terminated, single-group pilot study of a TEG algorithm used alongside traditional laboratory tests for blood management in patients requiring ECMO. The primary endpoint counts participants whose care follows the algorithm 90% of the time, from ECMO placement through 30-days post ECMO initiation.

Enrollment is recorded as 15. The registry lists no comparator group and no statistical analyses. It records 0 participants affected by serious adverse events, 0 affected by other adverse events, and 3 deaths; the relationship and attribution of these counts are not reported. The primary endpoint result, results for the other listed outcomes, and reason for termination are not reported in the registry record.