Regional Anesthesia Following Pediatric Cardiac Surgery: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Regional Anesthesia Following Pediatric Cardiac Surgery (NCT05688670), a randomized phase 4 study. The primary outcome is Total Amount of Opioid Medications Administered.

2. Clinical Question

The study’s stated purpose was to evaluate pain control following pediatric cardiac surgery with an ultrasound-guided regional anesthetic technique compared with surgeon-delivered wound infiltration. The primary endpoint was the total amount of opioid medication administered up to 12 hours after surgery, expressed in MME/kg. The posted primary results report group means and standard deviations for participants who completed the study, along with a two-sided comparison of the final values.

The endpoint addresses opioid administration rather than pain intensity directly. The registry also reports postoperative pain intensity and opioid use over a longer postoperative interval as secondary outcomes. Those measures add context, but they do not change the primary question. The results describe the observed groups in this pilot study; they are not, by themselves, a complete assessment of pain control or evidence about what should be done in an individual clinical situation.

3. Trial Design

This was a randomized, quadruple-masked, parallel-group pilot study listed as Phase 4. The registry record names Duke University as the sponsor and lists the study as completed. The study began on 2023-03-29, and the primary completion date is 2024-10-18. The recorded enrollment is 52.

The two groups were regional anesthesia and wound infiltration. The regional anesthesia arm is described as ultrasound-guided blocks; wound infiltration is described as surgeon-delivered. Ropivacaine 0.2% Injectable Solution is listed among the interventions. The registry’s brief description frames the comparison as local anesthesia delivered by an ultrasound-guided regional technique versus surgeon-delivered wound infiltration.

Randomization means that assignment to the study groups was intended to be determined by chance, rather than chosen by participants or clinicians. In general, random allocation can help make groups comparable at the start, although it does not guarantee balance in a small study. The registry identifies the design as parallel, meaning participants were assigned to one group rather than receiving both approaches in sequence. Quadruple masking indicates that the record classifies the trial as masked at four roles or levels; which people were masked and how masking was maintained are not reported in the registry record.

The primary outcome analysis includes 24 participants in the regional anesthesia group and 18 in the wound infiltration group. These outcome counts differ from the recorded enrollment of 52. The registry identifies the primary analysis population as participants who completed the study, but the reasons that the numbers differ and the handling of participants without primary outcome data are not reported in the registry record. The original sample-size rationale, randomization procedures, allocation concealment, and detailed protocol are also 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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Participants who completed the 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.

Population: Participants who completed data collection for the primary and secondary outcomes (up to 48 hours after surgery) are reported.

6. Primary Endpoint

The registry lists the primary outcome as Total Amount of Opioid Medications Administered, measured over Up to 12 hours after surgery.

The primary endpoint is the total amount of postoperative opioid medication administered up to 12 hours after surgery, expressed in morphine equivalents per kilogram (MME/kg). The registry describes this as a continuous measure summarized by its mean and standard deviation, among participants who completed the study. Expressing administered opioids in morphine equivalents places medications on a common scale, while dividing by body weight expresses the measure relative to participant size.

Opioid use is used as an indicator of postoperative analgesic medication consumption. It captures medication administered during the specified interval, rather than a direct rating of pain. Medication use may be relevant to a study of pain control, but it does not by itself describe every aspect of pain, comfort, recovery, or the reasons clinicians administered medication. The registry separately lists postoperative pain intensity as a secondary outcome, underscoring that pain measurement and opioid consumption are distinct outcomes.

The primary endpoint’s defined time window matters: it concerns medication administered up to 12 hours after surgery, not all medication use over the postoperative course. A secondary outcome reports opioid use up to 48 hours after surgery. Those time windows answer related but non-identical questions, so findings for one should not be treated as a substitute for the other.

7. Results Posted in the Registry

• Wound Infiltration: mean 0.83 versus 0.44 on control; difference 0.39 (95% CI 0.19 to 0.59), standardized effect d = 1.33; z-test p = <0.001.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Total Amount of Opioid Medications Administered

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Wound Infiltration: mean 1.57 versus 0.95 on control; difference 0.62 (95% CI 0.24 to 1.00), standardized effect d = 1.08; z-test p = 0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically higher for Wound Infiltration than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Postoperative Pain Intensity AUC

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Wound Infiltration: mean 94.50 versus 45.00 on control; difference 49.50 (95% CI 21.62 to 77.38), standardized effect d = 1.19; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically higher for Wound Infiltration than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The secondary outcomes broaden the picture beyond opioid use through 12 hours. They include opioid medication administered up to 48 hours after surgery and postoperative pain intensity measured over 48 hours. Across these outcomes, the posted group averages follow the same general direction as the primary result: the regional anesthesia group has lower means than the wound infiltration group. This directional consistency provides related evidence across medication use and a pain-intensity measure, but the endpoints capture different aspects of the postoperative experience and use different scales.

The secondary measures should be interpreted as complementary rather than interchangeable. Opioid amount records medication administered over a specified period. Pain intensity AUC combines pain scores across time into an area-under-the-curve measure. Their units and interpretation differ, so their numerical values should not be compared directly with each other or with the primary MME/kg estimate. The registry reports sponsor analyses for the secondary outcomes as well as group summaries.

Secondary results generally carry less evidential weight than the primary result when there are multiple endpoints and no reported plan for controlling the chance of false-positive findings across them. The registry record does not report whether a multiplicity adjustment was used, nor how these outcomes were ordered or prioritized for statistical testing. Without that information, the reported secondary p-values should be treated as exploratory or supportive rather than as independent confirmation. This caution does not erase the observed pattern; it places the pattern in the context of multiple comparisons and incomplete reporting of the analysis plan.

The listed secondary outcomes include a repeated listing of total opioid amount, and the record reports four outcome measures and six analyses overall. The exact relationship between the outcome listing and each analysis is not fully explained in the record. That uncertainty is another reason to focus on the broad descriptive pattern rather than treating each reported statistical test as a separate definitive conclusion.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Total Amount of Opioid Medications Administered
• Total Amount of Opioid Medications Administered
• Postoperative Pain Intensity AUC

9. Statistical Interpretation

10. Statistical Methods Explained

What does the reported mean difference represent?

The primary outcome is continuous: each participant’s opioid amount is represented on the MME/kg scale, and each group is summarized by a mean and standard deviation. The posted group averages are 0.44 for regional anesthesia and 0.83 for wound infiltration. The sponsor analysis reports a mean difference of -0.39 using the listed order of groups. A mean difference expresses the contrast between group averages in the original outcome units, so its interpretation remains in MME/kg. The sign depends on the order used to subtract one group from the other. Reading the means alongside the signed contrast avoids confusing the direction.

A mean is a measure of the group’s central value. A standard deviation describes the spread of individual observations around that group mean; it is not the uncertainty in the mean itself. In the primary outcome, the standard deviations are 0.19 and 0.39. In general, a larger standard deviation indicates more variability among observed participants, though it does not explain the source of that variability.

What does a two-sided t-test assess?

The registry reports a two-sided t-test for the mean difference in final values. In general, a t-test evaluates whether the observed difference in group means is compatible with a null hypothesis of no mean difference, while accounting for the variability and sample sizes used in the analysis. A two-sided test considers departures in either direction, rather than only a difference favoring one designated group. The registry reports the test result as p = 0.001 for the primary endpoint.

A p-value is conditional on the statistical model and null hypothesis. It is not the chance that the observed result happened “by chance” in an unrestricted sense, does not establish the probability that the treatment effect is real, and does not measure the size or practical importance of a difference. The estimate and confidence interval are needed to understand the direction and precision of the contrast. The specific assumptions used for the sponsor’s t-test beyond its two-sided designation are not reported in the registry record.

How should confidence intervals be understood?

A confidence interval communicates uncertainty around an estimated contrast. In general, a 95% confidence interval is produced by a procedure that, over repeated studies under its assumptions, would cover the underlying parameter in 95% of those studies. It is not a statement that there is a 95% probability that the fixed underlying parameter lies within the interval from this one study. For the primary result, the sponsor-reported interval is -0.59 to -0.18. Its endpoints are on the mean-difference scale and retain the direction of the reported contrast.

Intervals are useful because they show a range of estimates compatible with the data and analysis, rather than reducing the evidence to a thresholded p-value. They also reflect the precision available from the observed sample and variability. The interval does not account automatically for unreported design features, missing outcomes, multiplicity, or differences between this sample and other populations.

What do the re-calculated comparisons add?

The page includes simple unadjusted re-calculations from posted summary statistics. For the primary comparison, this re-calculation gives a mean difference of 0.39 in the wound infiltration group relative to the regional anesthesia group, with p < 0.001. This is consistent in direction and close in magnitude to the sponsor’s reported contrast of -0.39 when its group order is regional anesthesia relative to wound infiltration. The differing signs arise from expressing the comparison in opposite directions; they do not indicate opposite findings.

These re-calculations use summary statistics and are not a replacement for the sponsor’s analysis. They are unadjusted, so they do not incorporate any covariate adjustment or other analysis features that may not be represented in the posted group summaries. The registry’s own reported analysis remains the main reference for what the sponsor reported. The comparison helps readers understand how the group means relate to the reported contrast without implying access to participant-level data.

Why can over-dispersion matter?

In general, over-dispersion occurs when observations vary more than a statistical model expects. If a model understates the actual variability, its standard errors can be too small, making confidence intervals too narrow and p-values too small. Conversely, an analysis that adequately accounts for observed variation can better represent uncertainty. The reported primary analysis is a t-test of continuous final values, and the registry provides standard deviations for the two groups. It does not report a separate assessment of over-dispersion or a model adjustment for it; over-dispersion is therefore a general statistical consideration, not a documented feature of this analysis.

What can planning calculations say?

The accompanying sample-size illustrations use the observed effect as a starting point and show hypothetical participants per arm for specified target power levels and fractions of that observed effect. They are planning illustrations, not evidence of the power achieved in this trial. In general, power is the probability that a planned analysis will detect an effect of a specified size under stated assumptions when that effect is present. It depends on the assumed effect, variability, allocation, significance level, and analysis method. The trial’s own original sample-size justification and design assumptions are not reported in the registry record.

11. Confidence Intervals and Precision

The primary sponsor-reported estimate is a mean difference of -0.39, with a 95% confidence interval from -0.59 to -0.18. This interval describes uncertainty around the estimated difference in final values for the analyzed groups under the reported two-sided t-test. Because the interval does not include zero, it is consistent with a difference between group means under that analysis. That observation should be considered alongside the small number of participants contributing to the primary outcome and the limitations of the registry record.

The interval’s width reflects the precision available for this estimate: narrower intervals generally indicate greater precision, while wider intervals indicate more uncertainty about the size of the difference. Precision is not the same as clinical importance. An estimate may be relatively precise yet still require context to judge its relevance; an estimate may also be uncertain even when a test yields a small p-value.

The sponsor’s reported interval and the unadjusted re-calculation are not numerically identical in every detail, because the registry analysis and summary-statistic re-calculation are distinct procedures. The sponsor reports the analysis it conducted; the re-calculation is a simple comparison based on posted summaries. The record does not report participant-level data, additional adjustment details, or an explanation of possible differences between analytic approaches. The sponsor’s reported analysis is therefore the primary reference for the registry result.

Confidence intervals describe sampling uncertainty under the analysis assumptions. They do not capture every source of uncertainty, including missing data, measurement limitations, multiplicity, or whether results generalize to other settings. The confidence interval should be read as a measure of statistical precision for the reported contrast, not as a guarantee about future results.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The sample-size illustrations express the figures as participants per arm, not total events. They are based on two-sided significance level 0.05, equal allocation between the two arms, and a normal approximation. The effect to detect is set to a stated fraction of the observed effect. These are planning assumptions for the illustration; the registry record does not report the trial’s own original design assumptions or sample-size justification.

The 80% power column indicates the number of participants per arm in a hypothetical study planned to have an 80% probability of detecting the chosen effect under the illustration’s assumptions. The 90% power column represents a higher target probability of detecting that same specified effect. These targets describe hypothetical future-study planning, not the probability that the current study’s result is correct.

Rows for 100% of the observed effect use the full observed estimate as the planning target; rows for 75% and 50% use smaller target effects. The illustrations require more participants per arm as the assumed effect becomes smaller. This is expected in general: smaller differences are harder to distinguish from random variation, so a larger sample is typically needed to achieve the same target power, assuming the other planning assumptions remain unchanged.

The listed calculations are not observed power. They do not estimate the probability that this completed study detected an effect, and they should not be interpreted as a retrospective evaluation of the trial’s success. Planning figures based on an effect observed in a pilot can also be uncertain, because that effect may not be a stable estimate of the effect in a future study.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = 0.390; pooled standard deviation σ = 0.292.
2. n = 2 × (1.96 + 0.842)² × 0.292² / 0.390² = 8.8, rounded up to 9 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- 0.39                      # observed difference in means
sigma <- 0.292232783924049                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(5688670)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 9 (80% power), 12 (90% power)
 75% of observed effect: n per arm = 16 (80% power), 21 (90% power)
 50% of observed effect: n per arm = 36 (80% power), 48 (90% power)
power.t.test: 9.9 
Simulated power at n = 9 per arm: 0.756 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Analyses Reported by the Sponsor

The sponsor’s primary analysis is a two-sided t-test of the mean difference in final values. It reports a difference of -0.39, a 95% confidence interval from -0.59 to -0.18, and p = 0.001. The posted means are 0.44 for regional anesthesia and 0.83 for wound infiltration. The sponsor’s negative sign reflects its contrast ordering; expressed as wound infiltration relative to regional anesthesia, the simple unadjusted re-calculation is 0.39. The direction of the comparison is therefore consistent when the group order is made explicit.

The re-calculation uses posted summary statistics and is not an adjusted or participant-level analysis. Its p-value is p < 0.001. The sponsor’s reported confidence interval and p-value come from the sponsor analysis, while the re-calculation is a straightforward independent comparison from group summaries. The registry indicates no discrepancy between the posted analysis and the recalculation. As a matter of interpretation, the sponsor’s own analysis takes precedence over a simple re-calculation when describing the reported trial result.

The same general relationship between sponsor-reported analyses and re-calculations applies to the secondary outcomes: the sponsor reports two-sided t-tests, while the additional calculations are unadjusted comparisons of posted group summaries. These are different analytic summaries and should not be conflated. The registry does not provide details of any additional covariate adjustment or data-level modeling beyond the stated analysis method.

15. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when researchers examine several outcomes, comparisons, or analyses. In general, the more statistical tests conducted, the greater the chance that at least one test may appear statistically significant even if no corresponding effect exists. This does not mean that a particular finding is false; it means that the interpretation of a collection of p-values depends on how the tests were planned and whether the analysis accounted for them.

The registry identifies one primary endpoint and lists secondary outcomes for opioid use over a longer interval and postoperative pain intensity. It also reports multiple analyses. Whether the sponsor adjusted for multiplicity, used a hierarchy for testing outcomes, or treated some analyses as exploratory is not reported in the registry record. Therefore, the primary result has the clearest designated role, while secondary p-values warrant more caution. The statistical analysis plan and any interim analyses are not reported in the registry record.

The primary analysis population is described as participants who completed the study. The record reports outcome counts of 24 in the regional anesthesia group and 18 in the wound infiltration group. Enrollment is listed as 52, while the safety analysis lists 26 participants at risk in each group. The reasons for these different denominators are not reported in the registry record. It is also not reported whether participants without outcome data were excluded, whether their data were missing for particular reasons, or whether any imputation or sensitivity analysis was performed.

Missing data can affect estimates if participants with unobserved outcomes differ systematically from those with observed outcomes. In general, complete-case analyses may be biased under some missingness patterns, while imputation methods require assumptions about the missing observations. No specific missing-data assumptions or methods are reported in the registry record, so the direction or size of any potential effect cannot be assessed from these results alone.

The record does not report whether the primary analysis followed an intention-to-treat approach, how protocol deviations were handled, or how the analysis population was defined beyond completion of the study. Those details matter for understanding how closely the reported comparison reflects randomized assignment and for assessing possible bias. They should not be inferred from the outcome counts.

16. 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 safety record lists 26 participants at risk in each group. It reports zero serious adverse events in the regional anesthesia group and zero in the wound infiltration group. It also lists zero other adverse events and zero deaths in each group. No serious adverse event terms are listed.

These are counts recorded for the stated safety groups; they do not establish that no adverse events of any kind occurred outside the categories reported, or that the approaches have equivalent safety. A zero count in a study of this size can coexist with uncertainty about uncommon outcomes. The safety denominators also differ from the primary outcome analysis counts, and the registry does not explain the difference. The record’s adverse-event figures describe what was posted, not a complete estimate of risk in broader clinical use.

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

The results describe a randomized pilot study comparing ultrasound-guided regional anesthesia with surgeon-delivered wound infiltration after pediatric cardiac surgery. For the primary outcome, the posted average opioid amount through 12 hours was lower in the regional anesthesia group than in the wound infiltration group. The sponsor’s reported analysis estimates the contrast and provides a confidence interval and p-value for that comparison. Secondary outcomes show a broadly similar direction in the posted group means.

These findings do not establish that one approach works or does not work, and they do not determine what treatment is appropriate for any individual. The primary endpoint records opioid medication administered, not pain alone. The secondary pain measure offers a different view, but registry results from a pilot study do not by themselves establish a complete clinical benefit-risk profile.

The observed differences are estimates from the participants included in the analyses. They may not represent what would be observed in another group or setting. The registry does not explain the differences between enrollment, outcome, and safety counts; it also does not report the original sample-size rationale, detailed missing-data methods, multiplicity handling, or full statistical analysis plan. Each omission limits how confidently the reported estimates can be generalized or interpreted beyond the posted comparisons.

Statistical significance does not answer whether an effect is important in practice. The size of the estimate, its uncertainty, the outcome’s clinical relevance, potential harms, the study population, and consistency with other evidence all matter. Those broader questions cannot be resolved by a p-value alone. The most defensible reading is that the posted analyses show differences in the measured outcomes in this pilot sample, with uncertainty and reporting limitations that should remain visible.

18. Why This Trial Matters Statistically

This trial is statistically informative because it places two approaches to local anesthesia in a randomized comparison and reports outcomes that include both opioid consumption and postoperative pain intensity. Randomization can support a fairer comparison than an uncontrolled observational comparison, though it cannot guarantee that all relevant factors were balanced in a pilot sample. The parallel design and masked classification are important features of the recorded study design.

The study also illustrates why endpoint definition matters. The primary outcome is opioid amount in MME/kg over a specified postoperative interval, while the secondary pain outcome summarizes pain intensity over a longer period. A difference in medication consumption and a difference in pain scores are related questions, but they are not the same measure. Looking at both can help frame what the results address without collapsing distinct outcomes into one claim.

From a statistical perspective, the posted group means, standard deviations, confidence intervals, and p-values permit readers to distinguish effect direction from precision and test evidence. The sample-size illustrations further show how planning depends on the effect a future study aims to detect. They make clear that pilot estimates can be used to explore planning scenarios, but should not be treated as fixed truths about the effect.

The record also highlights the importance of complete reporting. Enrollment, analyzed outcome counts, and safety denominators do not match, and the reasons are not reported. The multiplicity strategy, missing-data handling, and original sample-size justification are also not reported. Such details are not administrative extras: they affect interpretation of uncertainty, potential bias, and the credibility of secondary findings. The study is therefore useful not only for its reported comparisons, but also as a reminder that statistical conclusions depend on both numerical results and transparent reporting of how those results were obtained.

19. 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.

Several limitations specific to this trial constrain interpretation. It is identified as a pilot study, and the primary analysis includes 24 participants in the regional anesthesia group and 18 in the wound infiltration group. Estimates from a pilot sample may be unstable, and the record does not report the study’s original sample-size justification. The displayed planning illustrations are based on observed effects rather than the trial’s own design assumptions.

The recorded enrollment is 52, while the primary outcome analysis counts are 24 and 18 and the safety record lists 26 participants at risk in each group. The reasons for these differing denominators are not reported in the registry record. The primary population is described as participants who completed the study, but the record does not explain exclusions, missing outcomes, or the handling of incomplete data. This makes it difficult to assess the influence of post-randomization exclusions or missingness.

The registry reports a two-sided t-test but does not report the detailed statistical analysis plan, assumptions beyond the stated method, any covariate adjustment, or interim analyses. It also does not report whether or how multiplicity was handled across secondary outcomes and analyses. These omissions leave uncertainty about the prespecification and interpretation of the multiple reported comparisons.

The outcome measures cover defined postoperative periods and should not be taken to describe all dimensions of pain, medication use, or recovery. The record does not explain the masking procedures or identify which roles were masked. It also does not provide detailed participant characteristics or information needed to assess how well the findings generalize beyond the study population. These limits do not negate the reported data, but they define the boundaries of what can be concluded from the registry record.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: Regional Anesthesia Following Pediatric Cardiac Surgery — NCT05688670.
• Registry record last updated 2025-08-28; status last verified 2025-08.
• Results first posted 2025-08-28.
• 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.

23. Record Summary

NCT05688670 is a completed, randomized, quadruple-masked, parallel-group pilot study sponsored by Duke University. It compares ultrasound-guided regional anesthesia with surgeon-delivered wound infiltration following pediatric cardiac surgery and lists enrollment of 52.

The primary outcome is mean opioid medication administered in MME/kg up to 12 hours after surgery among participants who completed the study. The sponsor reports a two-sided t-test with a mean difference of -0.39, a 95% confidence interval from -0.59 to -0.18, and p = 0.001. Secondary outcomes cover opioid use up to 48 hours and postoperative pain intensity over 48 hours. The registry also reports zero serious adverse events and zero other adverse events in each safety group, with zero deaths.

Important details—including the original sample-size rationale, missing-data handling, and multiplicity approach—are not reported in the registry record. The posted results should be read as estimates from the analyzed participants in a pilot study, with the reported outcome and safety denominators kept distinct.