The effect of tranexamic acid in fibrin sealant on adhesion formation in the rat

Safety and Efficacy of Local Tranexamic Acid for the Prevention of Surgical Bleeding in Soft-Tissue Surgery: A Review of the Literature and Recommendations for Plastic Surgery

BACKGROUND

Although high-bleed surgery routinely utilizes the antifibrinolytic drug tranexamic acid, most plastic surgical procedures are conducted in soft tissue with low-volume bleeding. Unease regarding possible systemic adverse effects prevents widespread systemic use, but local use of tranexamic acid is gaining popularity among plastic surgeons. Randomized controlled trials on topical use of tranexamic acid are mainly from high-bleed surgeries, and few studies address the effect in soft tissue. This article reviews the scientific evidence regarding local use of tranexamic acid in soft-tissue surgery, discusses pharmacological effects and possible adverse reactions, and presents recommendations for use in plastic surgery.

METHODS

A systematic search of databases for studies on local use of tranexamic acid in soft-tissue surgery was performed. Randomized controlled trials were included for a systematic review on effect; a narrative review regarding other clinically relevant aspects is based on extensive literature searches combined with the authors' own research.

RESULTS

Fourteen randomized controlled trials, including 1923 patients, were included in the systematic review on local use of tranexamic acid in soft-tissue surgery.

CONCLUSIONS

Local use of tranexamic acid may reduce blood loss comparably to intravenous prophylactic use with negligible risk of systemic adverse effects, but high-quality randomized controlled trials are few. Prolonged exposure to high local concentrations is discouraged, and direct contact with the central nervous system may cause seizures. No single superior means of administration or dosage is supported in the literature, and lowest effective dose is unknown. There may not be one single ideal dosing regimen, but rather many possibilities adaptable for different surgical situations.

Cytotoxicity and effect on wound re-epithelialization after topical administration of tranexamic acid

Background

Topical administration of tranexamic acid (TXA) reduces bleeding from surgical wounds similarly to intravenous use, but with negligible risk of adverse systemic events. Topical use is expanding, but is off‐label. Surgeons lack guidelines regarding safe topical dosages and modes of administration. The effects of topical TXA on skin cells and wound healing are unknown. This study investigated whether topical TXA might be cytotoxic or affect wound re‐epithelialization.

Methods

Human keratinocytes and fibroblast cell cultures and an ex vivo human skin wound model were subjected to both short (limited) and long (chronic) exposure to various clinically relevant concentrations of TXA to mimic different modalities of topical administration. Cytotoxicity and effects on wound re‐epithelialization were evaluated.

Results

In cell culture, toxicity from chronic exposure was associated with increasing concentration and exposure time. Limited exposure to TXA did not cause significant cytotoxicity even at high concentrations. Re‐epithelialization was completely absent in wounds chronically exposed to TXA concentrations of 25 mg/ml or above, and 50–100 mg/ml induced epidermolysis of normal epithelium, possibly by a non‐toxic mechanism. Wound re‐epithelialization was slightly delayed, but not impaired, by limited exposure to 100 mg/ml or chronic exposure to 6·25 mg/ml.

Conclusion

Although short exposure to even high concentrations of topical TXA seems well tolerated in vitro, prolonged exposure can be cytotoxic and may affect wound re‐epithelialization. Surgeons should adjust the TXA concentration to the planned mode of topical administration in clinical practice.

Tranexamic acid and hyaluronate/carboxymethylcellulose create cell injury

Background and Objectives:

Postoperative pelvic adhesions are associated with chronic pelvic pain, dyspareunia, and infertility. The aim of this study was to evaluate the adhesion prevention effects of tranexamic acid (TA) and hyaluronate/carboxymethylcellulose (HA/CMC) barrier in the rat uterine horn models on the basis of macroscopic and microscopic adhesion scores and histopathological as well as biochemical parameters of inflammation.

Methods:

Twenty-one Wistar rats were randomly divided into 3 groups. Ten lesions were created on the antimesenteric surface of both uterine horns by bipolar cautery. Three milliliters of 0.9% sodium chloride solution were administered in the control group. A single layer of 2 × 2 cm HA/CMC was plated in group 2. Two milliliters of TA was applied in the last group. All rats were sacrificed at postoperative day 21.

Results:

No significant difference was found among the control group, the HA/CMC group, and the TA group in terms of macro-adhesion score (P = .206) and microadhesion score (P = .056). No significant difference was found among the 3 groups in terms of inflammation score (P = .815) and inflammatory cell activity (P = .835). Malondialdehyde levels were significantly lower in the control group than in the TA group and HA/CMC group (P = .028). Superoxide dismutase and glutathione S-transferase activities were found to be higher in the control group than in the TA group (P = .005) and HA/CMC group (P = .009).

Conclusions:

TA and HA/CMC had no efficacy in preventing macroscopic or microscopic adhesion formation and decreasing inflammatory cell activity or inflammation score in our rat models. TA and HA/CMC increased the levels of free radicals and reduced the activities of superoxide dismutase and glutathione S-transferase enzymes, which act to reduce tissue injury.

Comparison of commercial fibrin sealants in facelift surgery: a prospective study

Background

The aim of this study was to compare the effects of two types of fibrin glue in patients undergoing facelift surgery.

Methods

A prospective, controlled “right-left side” study was carried out in 20 patients. The two fibrin sealants used were Quixil® and Tissucol®. The two sealants were used at the same time, ie, one on one side of the face and the other on the contralateral side. Comparisons were made with regard to rates of hematoma and seroma, degree of induration, edema, ecchymosis, pain levels, and patient satisfaction.

Results

The results were almost equivalent. The only exception was a significant (40 mL) hematoma in a patient treated with Quixil. Bleeding was most likely due to a sudden rise in blood pressure during the immediate postoperative period. However, it must be emphasized that, while Tissucol actually seals the undermined area, thus virtually eliminating the dead space, Quixil acts differently, in that its effectiveness in preventing hematoma is linked mainly to its hemostatic effect.

Conclusion

The two fibrin sealants used were nearly identical with regard to patient safety and quality of the result. Nevertheless, it is noted that, while Tissucol has both hemostatic and “gluing” effects, Quixil is mainly effective in securing hemostasis.

Evaluation of a fibrin preparation containing tranexamic acid (Adhexil) in a rabbit uterine horn model of adhesions with and without bleeding and in a model with two surgical loci

OBJECTIVE

To compare the efficacy of a fibrin preparation supplemented with tranexamic acid (Adhexil) with that of established devices, and to determine whether its effect is limited to the site of application.

DESIGN

Rabbit uterine horns were abraded in nonbleeding and bleeding variants of an established adhesions model. In a separate study, a sidewall excision with approximation of the abraded cecum was added. Animals randomly received Adhexil at both, neither, or either loci.

SETTING

Laboratory study.

ANIMAL(S)

Seventy-two female New Zealand White rabbits (Oryctolagus cuniculus).

INTERVENTION(S)

Adhexil, Seprafilm or SprayGel and Interceed.

MAIN OUTCOME MEASURE(S)

The extent of adhesions was evaluated 13 to 16 days after surgery.

RESULT(S)

Adhexil reduced adhesions (15 +/- 7%; 15 +/- 4%) compared with controls (74 +/- 13%; 78 +/- 9%) in the bleeding and nonbleeding models, respectively. The reductions resulting from the use of Seprafilm (39 +/- 17%; 34 +/- 14%) or SprayGel (61 +/- 18%; 43 +/- 14%) (n = 4) were not statistically significant. In the bleeding model, Interceed (48 +/- 15%) reduced adhesions only modestly.

CONCLUSION(S)

In the combined uterine and sidewall model, Adhexil reduced selectively the extent and incidence of adhesions. The absolute and relative performance of Adhexil in an established adhesions model and in the presence of bleeding justifies its further investigation.

Commercial Fibrin Sealants Are Not Equivalent in a Rabbit Liver-Resection Model Which Quantitatively Evaluates Hemostasis and Formation of Adhesions

A rabbit partial liver resection model was used to determine the hemostatic effectiveness of a new fibrin sealant. Persistent bleeding, with a mean bleeding time of 372 s and blood loss of 18 ml, from a resected lobe of the liver was achieved after rabbits in the untreated control group had been infused continuously with unfractionated heparin over 20 min with 0.2 IU/ml at a rate of 1 ml/min. Spraying the resected surface with the new fibrin sealant, Quixil, reduced bleeding to < 1 ml and the post-resection bleeding times was 25 s. Bleeding time, blood loss and the volume of sealant used in the rabbit model were inversely correlated with the thrombin concentration in the sealant. In direct comparisons with Tissucol and Beriplast, Quixil was associated with the shortest bleeding times, the lowest volume of sealant used and the lowest score of abdominal adhesions.

Significance of cyclooxygenase-2 induced via p38 mitogen-activated protein kinase in mechanical stimulus-induced peritoneal adhesion in mice

Postoperative peritoneal adhesion represents a major complication of surgery, but the molecular mechanism underlying pathogenesis of adhesion is not fully understood. The present study investigated the roles of cyclooxygenase (COX)-1 and COX-2 in peritoneal adhesion induced by scraping the surface of the cecum and abdominal wall in mice. Slight, but macroscopically observable, peritoneal adhesion was induced even on day 1, and the extent of adhesion reached a maximum on day 7 and beyond. COX-1 mRNA was constitutively expressed in the intact cecum, and its expression level was not altered after the mechanical stimulus. In contrast, expression of the COX-2 gene was markedly increased after the stimulus, and maximum expression was observed on days 3 to 7. Mofezolac, a specific COX-1 inhibitor, had no effect on peritoneal adhesion at 30 mg/kg and had only marginal effects on prostaglandin (PG)E2 levels in the cecum or peritoneal fluid. On the other hand, two highly selective inhibitors for COX-2, NS-398 (N-[2-(cyclohexyloxy)-4-nitrophenyl]-methanesulfonamide) and CAY10404 [3-(4-methylsulphonylphenyl)-4-phenyl-5-trifluoromethylisoxazole], dose-dependently inhibited both adhesion formation and the increase in PGE2 levels (3-30 mg/kg). The effects of NS-398 were eliminated when PGE2 or (R)-butaprost was administered exogenously. A COX-2 antisense oligonucleotide also attenuated adhesion formation. Activation of p38 mitogen-activated protein (MAP) kinase was observed in the traumatized cecum, and an MAP kinase inhibitor, SB202190 [4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)-1H-imidazole], inhibited adhesion formation (54% inhibition at 15 microM) and also reduced the COX-2 mRNA level and PGE2 levels. In conclusion, COX-2, but not COX-1, plays a significant role in mechanical stimulus-induced peritoneal formation in the mouse cecum.

Fibrin sealants in surgical or traumatic hemorrhage

PURPOSE OF REVIEW

Fibrin sealants have been used to control surgical hemorrhage for three decades, and numerous articles have reported their use in a variety of surgical procedures in both animal models and humans. This article reviews the recent literature on fibrin sealants with the specific aim of highlighting the use of fibrin sealants in planned and simulated trauma to provide background for clinicians who may consider using fibrin sealants in specific cases. An overview of the mechanisms of action of fibrin sealants, their indications, and current commercial formulations is also provided.

RECENT FINDINGS

Recent studies have evaluated the use of fibrin sealants in vascular surgery, including aortic anastomosis in an animal model, gastrointestinal anastomoses, plastic surgery, urologic procedures including heminephrectomy, and other procedures.

SUMMARY

Fibrin sealants continue to be used and evaluated in animal models and surgery. Their use in military settings and in civilian trauma centers, explored for several years, is not reported extensively in the literature. Recent events and the current tempo of military operations dictate that many potential scenarios exist for using fibrin sealants to control traumatic hemorrhage.