Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT02918201 |
| Other study ID # |
2020/6808 |
| Secondary ID |
2015-004342-2620 |
| Status |
Completed |
| Phase |
Phase 2
|
| First received |
|
| Last updated |
|
| Start date |
January 1, 2020 |
| Est. completion date |
June 30, 2022 |
Study information
| Verified date |
November 2023 |
| Source |
St. Olavs Hospital |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
After surgical procedures, interventions to reduce postoperative bleeding are of great
importance. In this study, the effect will be investigated of administering tranexamic acid,
which is designed for injection, directly onto the raw wound surface (topical application)
created during surgery. In this way only a small amount of drug is to reach a large wound
area. There will be a higher drug concentration of it in the exposed wound surface than after
injection, but only a very low concentration in the body, and no risk of injury from needles.
The researchers have recently shown that topically applicated tranexamic acid reduces
bleeding in women who had two-sided breast reduction surgery. Now it will be studied whether
topically applicated tranexamic acid reduces bleeding from superficial wounds, using as a
study model the homogenous wounds created by tangential skin excision when harvesting split
skin grafts for skin transplants. Two identical wound surfaces in the same patient will serve
as case and control.
Description:
One or more paired donor sites will be created for each patient using the Zimmer dermatome.
Paired wounds withcomparable size, depth, and location and will be labeled "A" and "B." A
study nurse not involved in the operation will prepare two identical vials of 20 ml saline,
marking them "A" and "B." A sealed numbered study envelope will state which vial should
receive TXA. In the study drug vial, 5 ml will be replaced with 5 ml of 100 mg/ml TXA,
yielding a solution of 25 mg/ml TXA. Both vials will receive 0,1 ml epinephrine 1 mg/ml,
yielding an epinephrine concentration of 5 µg/ml to match the hemostatic saline-epinephrine
solution applied topically to donor wounds at the burn center. The sets of vials and the
corresponding study ID numbers will be delivered to the operating theatre. Prior to
bandaging, the respective study wounds will be moistened with the corresponding study fluid.
Gloves will be changed between each application to avoid cross-contamination. The study
wounds will then be covered with an innermost non-absorbent layer of Vaseline gauze and five
dry surgical gauzes to absorb the blood and exudate. The weight of a single dry gauze is
consistent (27.5 g). The dressings will be marked "A" and "B" according to the drug vials
used.
On the first postoperative day, the dressings will be removed except for the innermost
Vaseline gauze. The wound surface area and the area of the blood stain on the innermost gauze
will be measured. Dressing weight gain will be calculated by weighing the five dry gauzes and
subtracting the dry weight (137.5 g). The paired gauzes will be visually compared for
bleeding.and photo documented for later direct comparison.
During the first 24 h and over the following days and weeks, the participants will be
monitored for possible adverse events, postoperative complications, and time to
re-epithelialization.
Randomization Computer-generated randomization, production of corresponding sealed study
envelopes, and organization of electronic case report forms will be provided by the Clinical
Research Unit of St. Olav's University Hospital, Trondheim, Norway. Randomization
instructions will be executed by a study nurse who was otherwise not connected to surgical
procedures or patient follow-ups. All participants and personnel involved in surgery,
follow-up, data collection, and statistical analysis will be blinded to the randomization.
Study end points The primary endpoint will be postoperative bleeding, defined as the net
weight gain of the dressings per wound area. The secondary endpoints will be blood stain to
wound area ratio and visual comparison of the amount of blood between paired dressings. All
variables will be recorded on the first postoperative day. Additional secondary outcomes will
be time to re-epithelialization, defined as no oozing in the dressings, and the occurrence of
complications, such as wound infections and thromboembolic events.
Statistical analysis A ≥ 25 % reduction in bleeding in TXA donor wounds will be considered
clinically significant. A delay in healing time or an increase in infection rate of ≥ 25 %
will be considered clinically significant. The standard deviation (SD) was uncertain, as few
similar studies exist but were estimated to be 0.4, based on previous effect studies22,23. As
each patient will be his or her own control, using a paired samples t-test to detect a
difference of 0.25, and a standard deviation of 0.4, α of 0.05, and power of 0.80, a sample
size of 23 wound pairs is needed (power calculation.
http://www.biomath.info/power/prt.htm25). We choose to include a total of 36 wound pairs for
additional power in case of technical difficulties, since previous effect studies do not use
the surrogate variables for bleeding used in this study. Continuous data will be analyzed
using the paired samples t-test for normally distributed data and Wilcoxon signed rank test
for non-normally distributed data. Categorical data will be analyzed using the chi-squared
test.
