Continuous Lidocaine Infusion for Management of Perioperative Burn Pain: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Continuous Lidocaine Infusion for Management of Perioperative Burn Pain (NCT02059902), a randomized phase 4 study. The primary outcome is Narcotic Consumption (Measured in mg/kg Narcotic Consumption).

2. Clinical Question

The trial asks whether perioperative lidocaine infusion is associated with differences in narcotic consumption and pain management among patients undergoing surgery for thermal burn injuries. The registry describes a comparison of lidocaine with normal saline, alongside usual postoperative pain management. Its stated rationale is that opioid requirements in burn patients may be underestimated and that relying on greater opioid use may not resolve perioperative pain concerns. Lidocaine is described in the record as having analgesic and other pharmacologic properties, but the trial results should be read as a comparison of posted outcomes, not as proof of a clinical benefit or harm.

The registry also describes comparisons of pain scores, opioid use, and narcotic equivalents related to body weight and burn surface area grafted. However, it posts one outcome measure and no secondary outcomes. The primary outcome is narcotic consumption rather than a direct measure of pain, so it addresses medication use and does not, by itself, establish how participants experienced pain.

3. Trial Design

This is a phase 4, randomized, parallel-group trial with quadruple masking. The two registered groups are Lidocaine and Normal Pain Management. The control group received normal saline as a bolus followed by continuous infusion; the intervention group received lidocaine by infusion. The registry lists an enrollment of 36 and a trial status of completed. The posted primary outcome data include 14 participants in each group. The record does not explain the difference between the enrollment figure and the number included in the primary outcome results.

The registry gives a start date of 2012-09 and primary completion date of 2014-09. Its intervention description specifies a pre-operative lidocaine dose over at least 30 minutes, a higher infusion rate at incision, and a reduced rate for the remainder of the post-operative period. The normal saline arm is described as receiving an equal-volume placebo infusion. The record also says clinical staff followed a standardized postoperative pain-management strategy using morphine and oxycodone based on a standardized pain-scale rating tool.

Random allocation is intended to make treatment groups comparable on average, while masking is intended to reduce the influence of treatment knowledge on care and assessment. Those design features do not guarantee that groups were balanced in this particular trial, especially with the posted outcome counts. The registry record does not report the allocation sequence method, concealment procedures, who was included in the quadruple masking, or whether masking was assessed. It also does not report the detailed eligibility criteria, the sites where participants were treated, or how the reported analysis population was defined. Those omissions limit how fully the design and implementation can be evaluated from the registry record alone.

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.

Before assignment: 36 patients were consented during the study period, 28 patients randomized and treated: 14 placebo vs. 14 lidocaine. Patients were excluded after signing consent for: arriving to the pre-op area wearing a Lidocaine patch, changes in surgery times, lack of grafting/surgery needs, and medical contraindications (such as lidocaine with metoprolol).

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 Narcotic Consumption (Measured in mg/kg Narcotic Consumption), measured over 24-hours post surgery.

The primary endpoint is narcotic consumption, measured in mg/kg and reported as a median with an inter-quartile range. The registry lists the measurement timeframe as 24-hours post surgery. Narcotic consumption is a measure of the amount of opioid medication used, rather than a direct measurement of pain intensity. In this trial, it is relevant because the stated research question concerns whether adding perioperative lidocaine changes opioid use during burn surgery recovery.

A median describes the center of the observed values: half of the values are at or below it and half are at or above it. The inter-quartile range describes the middle half of the observations, from the lower quartile to the upper quartile. These summaries are useful when outcome values are not normally distributed, as the registry says was the case for its analysis. They do not show every participant’s consumption, and overlapping or non-overlapping ranges do not by themselves establish whether a group difference is statistically persuasive.

The posted median was 57.5 mg/kg in the Normal Pain Management arm, with an inter-quartile range from 35.0 to 105.0. In the Lidocaine arm, the median was 67.75 mg/kg, with an inter-quartile range from 50.0 to 134.0. The outcome description also refers to comparisons over the 72-hour post-operative period, while the primary endpoint timeframe is listed as 24-hours post surgery. The registry record does not clarify this difference in the stated time window.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a randomized, parallel-group comparison and identifies an unadjusted Wilcoxon rank sum test for the outcome data, with non-normal data distribution given as the reason for choosing that test. No inferential results for the test are posted. Understanding what the method does helps distinguish the descriptive summaries from a formal comparison, but cannot replace the missing analysis results.

Why use a rank-sum test?

General statistical explanation: a rank-sum test converts the observed values from both groups into ranks and assesses whether values in one group tend to be higher or lower than values in the other. It does not require the outcome itself to follow a normal distribution. This can be useful when the outcome distribution is skewed or contains extreme values. The registry identifies non-normality as the reason for using this test, but does not describe the distribution’s shape or how that assessment was made.

A rank-sum test is not simply a test of the difference between two medians in every situation. Its interpretation concerns the relative distributions of observations. If the distributions have similar shapes, a difference in location can be a reasonable shorthand, but the record does not report whether that condition held. The medians and inter-quartile ranges describe the groups; without a test statistic, p-value, or confidence interval, they do not reveal the result of the stated rank-sum test.

What does “unadjusted” mean?

General statistical explanation: an unadjusted comparison evaluates the groups without statistically controlling for other measured characteristics. That can be an appropriate simple comparison in a randomized trial, since random allocation is intended to balance characteristics on average. In a small trial, however, chance imbalances can still occur. The registry does not report adjusted analyses or details of baseline characteristics, so it is not possible to assess whether adjustment was considered or whether groups differed at baseline.

The record says the comparison used an unadjusted Wilcoxon rank sum test, but does not state the exact test implementation, whether a continuity correction was used, how ties were handled, or whether a one-sided or two-sided test was prespecified. The record also does not include a confidence interval for a treatment effect. A confidence interval would express the uncertainty around an estimated difference or other effect measure; its absence means readers cannot assess the range of effect sizes compatible with the analysis.

How should medians and inter-quartile ranges be read?

General statistical explanation: the median is a robust measure of the center of a distribution, and the inter-quartile range describes its central spread. This pair of summaries is often informative for skewed data, but it omits details such as the tails, clustering, and individual observations. The posted median was 57.5 mg/kg in the Normal Pain Management group and 67.75 mg/kg in the Lidocaine group. The corresponding inter-quartile ranges were 35.0 to 105.0 and 50.0 to 134.0. These values describe the observed groups; they do not by themselves quantify the uncertainty in a between-group effect.

What do the planning illustrations represent?

The registry record includes assumptions for planning illustrations based on the observed effect: a two-sided significance level of 0.05, equal allocation between the arms, a normal approximation, and an effect to detect expressed as a stated fraction of the observed effect. Such calculations are hypothetical planning exercises. They do not show the trial’s actual design rationale, and they are not observed power. The record does not report the original sample-size justification, the target effect used when planning the trial, or whether any planning calculation formed part of the protocol.

General statistical explanation: sample-size planning asks how many participants would be needed under specified assumptions to detect a target effect with a chosen probability, if the assumptions hold. When the target is derived from the observed effect, the illustration is retrospective and can be sensitive to the particular estimate observed in a small study. It should not be treated as evidence that the completed trial had adequate precision or that a nonsignificant finding, if one were reported, showed equivalence. No such finding is posted in the registry record.

What remains unavailable?

The record reports zero posted analyses and does not include an inferential result for the primary outcome. It also does not describe missing-data procedures, analysis populations, sensitivity analyses, interim analyses, or multiplicity procedures. Those omissions make it impossible to reconstruct the complete statistical analysis or to evaluate whether the posted summaries represent all randomized participants. The stated test and descriptive values are therefore the extent of the statistical evidence that can be interpreted from the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists one outcome measure and no posted secondary outcomes. Its study description mentions pain scores, opioid use, and narcotic equivalents based on body weight and burn surface area grafted, but those additional outcomes are not posted as outcome measures in the record. The registry therefore does not provide a complete set of results for the broader outcome comparisons described in the study summary.

Multiplicity refers, in general, to the increased chance of finding an apparently unusual result when many outcomes or comparisons are tested. The registry record does not report a multiplicity adjustment, a hierarchy of outcomes, or a prespecified strategy for handling multiple comparisons. It is not possible to determine from the record whether such procedures were included in a protocol or analysis plan.

The record gives an enrollment of 36, while the primary outcome summaries include 14 participants in each arm. It does not explain the difference. The number of participants with missing primary outcome data, reasons for any missingness, and methods used to address missing data are not reported in the registry record. The analysis population is also not reported: readers cannot tell whether the summaries reflect all randomized participants, participants who received treatment, or participants with available outcome measurements.

The registry does not report whether outcomes were analyzed according to randomized assignment, whether protocol deviations occurred, or whether sensitivity analyses were conducted. It also does not report interim analyses or stopping rules. These details matter because they affect how prespecified and complete the reported comparison is. With no analysis results posted beyond the descriptive arm summaries, the treatment effect and its uncertainty cannot be evaluated from the registry record.

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.

The posted adverse-event figures list 14 participants at risk in each arm. In both the Normal Pain Management and Lidocaine arms, the record reports zero serious adverse events, zero other adverse events, and zero deaths. No serious adverse-event terms are listed.

These are counts in the registry record, not evidence that no adverse events occurred outside the record’s reporting framework. The record does not specify the adverse-event collection period, definitions, ascertainment procedures, or whether all randomized participants were included in safety follow-up. It also does not provide event-level descriptions or explain how the number at risk was determined. The posted figures should therefore be read as what was recorded, not as proof that the interventions are risk-free.

With 14 participants at risk in each arm, the safety summaries cover a limited number of participants. A count of zero cannot rule out uncommon harms or establish that risks are the same between groups. The registry also does not report a formal comparative safety analysis or uncertainty intervals for adverse-event rates. The record supports only the narrow statement that no serious adverse events, other adverse events, or deaths were recorded in either listed group.

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

The posted results describe narcotic consumption in the two randomized groups. The median was 57.5 mg/kg in the Normal Pain Management arm and 67.75 mg/kg in the Lidocaine arm. The inter-quartile ranges were 35.0 to 105.0 and 50.0 to 134.0, respectively. The values show a higher posted median in the Lidocaine group, with variation among participants in both groups. The registry does not post an inferential test result or an uncertainty interval for this comparison.

That pattern does not establish a causal effect, a statistically persuasive difference, or equivalence between treatments. Randomization supports a comparative design, but the posted analysis information is too limited to evaluate the result beyond the descriptive summaries. The registry’s stated use of a Wilcoxon rank sum test is not accompanied by its result. Without that result and a measure of uncertainty, readers cannot determine how compatible the observed group summaries are with random variation.

The outcome is medication consumption, not pain intensity or quality of recovery. The registry’s broader description mentions pain scores and medication doses, but those results are not posted as secondary outcomes. Accordingly, the primary outcome cannot show whether pain differed, whether a given amount of narcotic use was adequate, or whether other aspects of perioperative care changed.

The registry lists 36 enrolled participants but reports primary outcome results for 14 participants in each arm. It does not explain who was omitted from the outcome summaries or why. The absence of reported missing-data methods and analysis populations further limits interpretation. The record also does not report a sample-size justification, so the precision and design adequacy cannot be judged from the enrollment figure alone.

The appropriate conclusion is descriptive and limited to the posted endpoint: the two groups have the reported medians and inter-quartile ranges, and no inferential result is available in the registry record. The summaries do not establish that lidocaine improves or worsens pain management, nor do they resolve the safety of the intervention.

13. Why This Trial Matters Statistically

This trial is statistically informative as an example of why design labels and descriptive summaries are not enough to interpret a clinical comparison. It is randomized, parallel-group, and quadruple-masked, features that can strengthen a comparison by reducing some sources of systematic bias. At the same time, the posted primary outcome results include 14 participants in each arm, and the registry does not explain how those numbers relate to the enrollment of 36.

The outcome is reported as a median and inter-quartile range, consistent with the registry’s statement that the data were non-normal and compared using an unadjusted Wilcoxon rank sum test. These summaries make the scale and spread of observed narcotic consumption visible, but they do not replace an inferential result. Without a test result or confidence interval, the reader cannot assess statistical uncertainty or the range of effects compatible with the data.

The trial also illustrates the importance of aligning the outcome description with its measurement window. The primary outcome is listed at 24-hours post surgery, while the outcome description refers to a comparison over the 72-hour post-operative period. The record does not clarify the relationship between those statements. Such ambiguity makes it harder to know precisely which observation period the reported summary represents.

Finally, the distinction between registry enrollment and the reported analysis group, the absence of posted secondary outcomes, and the missing analysis details all affect how much can be concluded. Statistical interpretation depends not only on the treatment comparison but also on clear definitions of outcomes, analysis populations, and uncertainty. The record illustrates why these details are essential for evaluating clinical trial evidence without over-reading descriptive results.

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.

Several limitations are specific to what this registry record reports. Although the trial lists an enrollment of 36, the primary outcome is summarized for 14 participants per arm. The reason these figures differ is not reported in the registry record. The record does not state how many participants were randomized, how many received their assigned infusion, or whether the outcome summaries include all participants with available data.

The primary outcome timeframe is listed as 24-hours post surgery, while its description says the difference in narcotic consumption and number of pain medication doses over the 72-hour post-operative period was compared. The registry record does not clarify whether the posted median refers to the 24-hour or 72-hour period. That uncertainty complicates interpretation of the endpoint’s precise time window.

The record describes an unadjusted Wilcoxon rank sum test but does not post its result. No p-value, confidence interval, test statistic, or effect estimate is reported. The record also does not report the distribution of individual outcomes, baseline characteristics, missing-data handling, analysis populations, or sensitivity analyses. It is therefore not possible to assess the degree of uncertainty, determine whether groups differed at baseline, or establish how robust the comparison might be.

The broader study description mentions pain scores and other medication-related outcomes, but only one outcome measure is posted and no secondary results are available. The registry record does not report a sample-size justification or enough information to evaluate the adequacy of the planned sample. Finally, the intervention dose is transcribed in the arm description with units written as 1.5kg/mg for the pre-operative and post-operative doses; the registry record does not clarify that notation. These reporting gaps constrain conclusions from the posted data.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Continuous Lidocaine Infusion for Management of Perioperative Burn Pain — NCT02059902.
• Registry record last updated 2018-07-03; status last verified 2018-06.
• Results first posted 2017-06-07.
• 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

The registry record describes NCT02059902, a completed phase 4 randomized, quadruple-masked, parallel-group trial of lidocaine infusion versus normal saline for perioperative burn pain. It lists an enrollment of 36 and dates the trial from 2012-09 to primary completion in 2014-09. The posted primary outcome is median narcotic consumption in mg/kg, with an inter-quartile range, at 24-hours post surgery.

The Normal Pain Management arm had 14 participants in the primary outcome summary, with a median of 57.5 and an inter-quartile range from 35.0 to 105.0. The Lidocaine arm also had 14 participants, with a median of 67.75 and an inter-quartile range from 50.0 to 134.0. The record describes an unadjusted Wilcoxon rank sum test because the data were non-normal, but no test result is posted. It lists zero serious adverse events, other adverse events, and deaths in each arm. Missing-data methods, analysis populations, and the reason the outcome counts differ from enrollment are not reported in the registry record.