Chloroprocaine Lavage to Improve Outcomes Related to Operative Cesarean Delivery: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Chloroprocaine Lavage to Improve Outcomes Related to Operative Cesarean Delivery (NCT03760718), a non-randomized early/phase 1 study. The primary outcome is Chloroprocaine Plasma Concentration at 1 Minute.

2. Clinical Question

The registry’s brief summary sets out a longer-term objective of investigating intraperitoneal chloroprocaine as an alternative option intended to avoid general anesthesia during cesarean delivery, alleviate discomfort from surgical pain, reduce complications, and improve the birth experience. Those goals describe the broader motivation, not demonstrated outcomes of this record. The stated immediate objectives are pharmacokinetic and safety-oriented. The posted primary endpoint is a concentration measurement, not a direct measure of pain, anesthesia use, complications, or birth experience.

3. Trial Design

The registry identifies this as an early phase 1, parallel, nonrandomized study with no masking. It is marked completed, with an enrollment of 15. The sponsor is Oregon Health and Science University. The three intervention groups are described as receiving 40 ml of preservative-free chloroprocaine at concentrations of 1%, 2%, and 3%. The registry does not describe how participants were assigned to those groups, so the allocation process cannot be characterized beyond its nonrandomized designation.

A parallel design means that the record organizes participants into separate intervention groups rather than describing each participant as receiving every intervention in sequence. That general design description does not establish whether the groups were formed at the same time, whether concentration selection followed a particular rule, or whether other aspects of care were comparable. Those details are not reported in the registry record.

Because allocation was nonrandomized and there was no masking, the concentration groups should not be treated as though they were randomized, blinded comparison arms. The registry explicitly cautions that the arms are not a like-for-like control comparison. Differences between groups could reflect factors other than the assigned concentration; the posted record does not provide enough detail to determine how such factors were handled.

The study’s primary outcome is a continuous measure: mean chloroprocaine plasma concentration in a venous sample at 1 minute after intraperitoneal administration, with a 95% confidence interval as the stated dispersion measure. The broader objectives include describing a plasma concentration-time profile and the incidence of side effects. The record lists 8 outcome measures, but does not report their results in the information available for this analysis. It lists 0 analyses. A protocol, detailed statistical analysis plan, eligibility criteria, and participant flow 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 Chloroprocaine Plasma Concentration at 1 Minute, measured over 1 minute after intraperitoneal chloroprocaine administration.

The primary endpoint is the chloroprocaine concentration in a venous blood sample collected 1 minute after intraperitoneal chloroprocaine administration. The registry specifies that the result is to be expressed as a mean and accompanied by a 95% confidence interval. The measurement is intended to characterize how much chloroprocaine is present in plasma shortly after administration. The registry’s broader objective is to describe absorption and develop a plasma concentration-time profile.

As a general statistical concept, a mean describes the central value of a continuous measurement across the observations included in an analysis. A confidence interval communicates uncertainty around an estimated mean: it gives a range of values compatible with the data and the method used to construct the interval. Its width depends on factors such as the amount of variability and the number of observations contributing to the estimate. It is not a range in which every participant’s concentration is expected to fall.

The concentration at 1 minute is a pharmacokinetic measurement, not a direct measure of the broader goals described in the study summary. It does not itself quantify pain, avoidance of general anesthesia, complications, or birth experience. The registry record does not report the group means, confidence interval limits, individual observations, or other concentration-time results. Therefore, the direction and precision of the observed concentration findings cannot be assessed from the posted results described in this record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes the primary outcome as a continuous measure summarized by a mean and a 95% confidence interval. These are statistical summaries, not the results themselves. The concentration mean and confidence interval are not reported in the registry record, so the endpoint’s observed value and uncertainty cannot be discussed quantitatively.

What does a mean describe?

As a general concept, a mean represents the arithmetic center of a set of numerical observations. It can be useful when the research question concerns an average concentration across participants or samples. But an average does not show the full distribution. It does not indicate whether individual values are close to the mean, widely dispersed, or influenced by unusually high or low observations. Those features are often assessed using additional summaries or plots; participant-level observations and such summaries are not reported in the registry record.

What does a confidence interval communicate?

As a general concept, a confidence interval expresses uncertainty in an estimate under a specified statistical method. A narrower interval indicates greater precision under that method, while a wider interval indicates less precision. The interval is not a guarantee that the true value lies within its limits, and it is not a prediction interval for individual participants. Interpreting it requires the estimate, interval limits, and enough information about the analysis to understand how the interval was constructed. The record specifies a 95% confidence interval, but the limits and calculation details are not reported in the registry record.

What can be learned from the group structure?

The parallel model indicates that the record organizes participants in separate groups. The interventions are 40 ml of preservative-free chloroprocaine at concentrations of 1%, 2%, and 3%. The allocation is nonrandomized, and the registry cautions that the arms are not a like-for-like control comparison. In general, random assignment helps balance measured and unmeasured characteristics across groups, on average. Without randomization, differences in outcomes may reflect group composition or other factors as well as the intervention. The registry does not report the assignment procedure or adjusted comparative analyses.

The lack of masking is another design feature to consider. In general, masking can reduce the influence of expectations on some measurements, reporting, or clinical decisions. Its importance depends on the outcome and how it is collected. The primary endpoint is a laboratory concentration measurement, but the record does not describe sample handling, laboratory procedures, assessor masking, or quality-control methods. Those methods are not reported in the registry record.

How should the side-effect counts be read?

For the safety summaries, the registry reports numbers at risk and numbers affected. These counts describe what was recorded in each group; they do not quantify uncertainty or establish that one concentration is safer than another. General comparison of adverse-event counts should account for group size, event definitions, follow-up, and ascertainment. The record reports five at risk in each group and reports no participants affected by serious adverse events. It does not provide serious event terms, and the list of top serious terms is empty. Descriptions of event types, severity rules, timing, and follow-up are not reported in the registry record.

What is the status of the statistical analysis?

The record lists 0 analyses. It does not report an analysis plan, modeling approach, handling of outliers, distributional assumptions, missing-data procedures, or adjustment for covariates. These omissions do not show that no analysis was performed; they mean that the analysis methods are not reported in the registry record. The posted primary endpoint definition alone is not enough to determine whether the method used matched the design or the observed data.

The record includes planning assumptions for an illustration based on the observed effect: a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the effect to detect stated as a fraction of the observed effect. These are described as planning assumptions, not as the trial’s own design. The numerical planning results and the observed primary effect are not reported in the registry record. Such planning quantities should be understood as hypothetical design illustrations, not as observed power or evidence that the study was adequately powered.

As a general concept, small studies often provide limited precision and limited ability to characterize uncommon outcomes. That does not determine the precision of this study’s primary estimate, because its estimate and interval are not reported. It does mean that the safety counts should be read descriptively rather than as definitive comparative evidence. Any further statistical interpretation would require results and analysis details that are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry identifies a primary endpoint, chloroprocaine plasma concentration at 1 minute, and lists 8 outcome measures. It lists 0 analyses. The record does not report how the outcomes were prioritized beyond the primary endpoint, whether any outcomes were exploratory, or whether a multiplicity adjustment was planned or used. Those details are not reported in the registry record.

As a general statistical concept, multiplicity arises when several outcomes, time points, groups, or comparisons are examined. The more questions considered, the greater the chance that at least one result may appear noteworthy by chance if each is evaluated separately. Methods such as prespecifying a primary endpoint or adjusting for multiple comparisons can help control interpretation, but the appropriate approach depends on the study’s goals and analysis plan. The record’s primary endpoint designation helps identify the main stated question; it does not reveal how results across the remaining outcomes were handled.

The registry does not report whether observations were missing, how missing measurements were handled, or whether analyses used all enrolled participants or a defined subset. The analysis population and participant flow are not reported in the registry record. Without this information, it is not possible to determine whether the reported endpoint—whose estimate is itself not reported—would represent all enrolled participants or only those with available measurements.

Interim analyses, stopping rules, and a detailed statistical analysis plan are not reported in the registry record. No conclusion should be drawn about whether those procedures existed or were used. The nonrandomized allocation is reported, but the method of assignment, any covariate adjustment, and any approach to account for differences between groups are not reported. These omissions limit assessment of both the comparisons and the completeness of the analysis.

In general, reporting the outcome definitions, analysis populations, missing-data handling, and multiplicity strategy makes it easier to distinguish planned analyses from exploratory findings. Those details are needed to judge how robustly the posted results address the stated objectives. The available registry information does not provide them.

11. 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.

Most frequent non-serious adverse event terms

The registry reports serious adverse events for each chloroprocaine group. In Group 1, zero participants were affected by serious adverse events among five at risk; in Group 2, zero among five; and in Group 3, zero among five. The registry reports zero deaths in each group. The list of top serious adverse event terms is empty.

For other adverse events, the record reports one affected participant in Group 1, two in Group 2, and one in Group 3, with five at risk in each group. These are group-specific counts, not comparative estimates adjusted for differences between participants or other factors. No event descriptions, severity details, timing, or follow-up information are reported in the registry record.

As a general statistical point, observing no serious adverse events in a small study does not establish that serious events cannot occur. The counts describe what was recorded during the study; they do not provide a precise estimate of risk or rule out uncommon events. Likewise, the differences in other adverse-event counts should not be interpreted as evidence of a concentration effect. The nonrandomized design and limited information on event ascertainment constrain comparisons.

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

The record documents a completed early phase 1 study of intraperitoneal preservative-free chloroprocaine at three concentrations. Its immediate objectives were to characterize absorption into the blood, describe a plasma concentration-time profile, and determine the incidence of side effects. The primary endpoint is a mean venous plasma concentration at 1 minute, with a 95% confidence interval specified as the measure of dispersion.

The primary concentration estimate and its interval are not reported in the registry record. Therefore, the posted information does not show the measured concentration at 1 minute, the uncertainty around that estimate, or how concentrations compared across groups. It also does not show a complete concentration-time profile. The registry lists 8 outcome measures but does not report their results in the information.

The findings described in the record cannot establish the longer-term aims stated in the study summary. A concentration measurement does not directly demonstrate avoidance of general anesthesia, reduced surgical pain, fewer complications, or an improved birth experience. Results for those clinical outcomes are not reported in the registry record. The study’s stated objectives and its primary endpoint should be kept distinct from its broader motivation.

The safety counts show no participants affected by serious adverse events in the three groups and no deaths. Other adverse events were reported for one participant in Group 1, two in Group 2, and one in Group 3. These observations are descriptive, and the registry does not provide event terms or details needed for a fuller assessment. They do not establish comparative safety or exclude uncommon harms.

The nonrandomized allocation is an important interpretive limitation. The registry explicitly says the arms are not a like-for-like control comparison. Any apparent group differences would not, on this design information alone, establish that the concentration caused those differences. In general, causal interpretation depends on the assignment process, comparability of groups, outcome measurement, and analysis methods. Several of those details are not reported in the registry record.

13. Why This Trial Matters Statistically

This study is statistically notable because its stated immediate aims are chiefly about pharmacokinetics and safety: measuring chloroprocaine in blood, developing a concentration-time profile, and describing side effects. Those aims differ from the broader clinical goals in the brief summary, which concern anesthesia use, discomfort, complications, and birth experience. Keeping the measurement question separate from the longer-term objectives helps prevent a concentration endpoint from being read as a clinical outcome.

The record also illustrates the limits of interpreting groups formed without randomization. The three concentrations create a natural basis for descriptive comparison, but the registry identifies the study as nonrandomized and warns that the arms are not like-for-like control groups. As a general statistical principle, a difference between nonrandomized groups can reflect differences in participants or circumstances as well as an intervention. Clear reporting of assignment, baseline characteristics, and analysis choices is important for understanding such comparisons; those details are not reported in the registry record.

Precision is central to interpreting continuous outcomes. The registry specifies a mean and a 95% confidence interval for the primary concentration endpoint, but neither the estimate nor its interval is reported. Without them, readers cannot assess the observed level, variability, or precision. The method is named, but its numerical result is absent.

The safety counts further show why descriptive results should not be overstated. No serious adverse events or deaths are reported, while other adverse events are recorded in the groups. With the nonrandomized design and limited event detail, those counts do not establish a causal safety comparison. More broadly, a small early phase 1 study can inform characterization and future research questions, but its role should not be confused with demonstrating broader clinical outcomes. The record’s stated aims, design, and available results define what can be interpreted.

14. 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 most consequential limitation for statistical interpretation is that the primary endpoint result is not reported in the registry record. Although the endpoint is defined as a mean plasma concentration at 1 minute with a 95% confidence interval, neither the mean nor interval limits are available. Concentration measurements at other times, group-specific estimates, and results for the other listed outcome measures are also not reported in the registry record.

The nonrandomized allocation limits direct comparison among the three concentration groups. The registry itself cautions that the arms are not a like-for-like control comparison. The assignment procedure, baseline characteristics, and methods for addressing possible group differences are not reported. No placebo or untreated comparison group is described in the record.

The registry identifies the study as unmasked. It does not report details about laboratory procedures, sample handling, outcome assessment, or quality control. Although the primary outcome is a plasma concentration, those methodological details would help readers assess measurement reliability. Eligibility criteria, participant flow, and the analysis population are not reported in the registry record.

The record lists 8 outcome measures but 0 analyses. A detailed statistical analysis plan, multiplicity strategy, missing-data handling, interim analyses, and stopping rules are not reported. The available safety information is also limited: serious adverse event terms are not listed, and detailed descriptions and timing of other adverse events are not reported. These limitations prevent a fuller assessment of the study’s analysis, completeness, and safety findings.

Finally, the stated primary endpoint is a short-term concentration measurement. The registry does not report results for the broader clinical goals described in its summary, including anesthesia use, discomfort, complications, or birth experience. Those goals should not be inferred from the endpoint definition.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Chloroprocaine Lavage to Improve Outcomes Related to Operative Cesarean Delivery — NCT03760718.
• Registry record last updated 2024-09-19; status last verified 2024-04.
• Results first posted 2024-09-19.
• 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.

18. Record Summary

NCT03760718 is a completed early phase 1, parallel, nonrandomized study sponsored by Oregon Health and Science University. It evaluates intraperitoneal preservative-free chloroprocaine at concentrations of 1%, 2%, and 3%; each group description specifies 40 ml. The registry lists an enrollment of 15 and identifies no masking.

The primary endpoint is the mean chloroprocaine plasma concentration in a venous sample collected 1 minute after administration, with a 95% confidence interval specified. The registry’s broader objectives concern blood absorption, a plasma concentration-time profile, and side effects. The primary concentration estimate and other outcome results are not reported in the registry record.

Safety information reports no serious adverse events or deaths in the groups, and reports other adverse events affecting one participant in Group 1, two in Group 2, and one in Group 3. The registry warns that the nonrandomized arms are not a like-for-like control comparison. The record lists 8 outcome measures and 0 analyses.