Does low molecular weight heparin impair anastomotic wound healing?

Effects of montelukast on the healing of ischemic colon anastomoses

BACKGROUND

The aim of this study was to examine whether treatment with montelukast, a selective leukotriene antagonist, would affect anastomotic healing in a reperfused colon rat model with remote ischemia/reperfusion injury.

METHODS

Rats (n = 12 per group) were intraperitoneally administered normal saline or 10 mg/kg montelukast sodium 60 minutes before and for 5 days after surgery. Ischemia was induced for 45 minutes through superior mesenteric artery occlusion. A left colon anastomosis was made. Blood and perianastomotic tissue samples were obtained on postoperative day 5.

RESULTS

Mean anastomotic bursting pressures of the control and montelukast groups were 159.17 ± 29.99 and 216.67 ± 26.40, respectively (P < .001). Compared with saline, montelukast treatment increased the mean tissue hydroxyproline level (2.46 ± .30 vs 3.61 ± .33 μmol/L) and decreased tissue caspase-3 activity (36.06 ± 5.72 vs 21.78 ± 3.87) and malondialdehyde levels (3.43 ± .34 vs 2.29 ± .34 nmol/g) (P < .001 for all). Other plasma markers of injury also showed differences.

CONCLUSIONS

Montelukast prevented ischemia/reperfusion-induced damage in a rat model of colonic anastomotic wound healing.

Is it really necessary to delay intranasal steroid treatment after FESS? An animal study

OBJECTIVES

The aim of this study is to investigate the effect of early intranasal steroid administration on wound healing after sinus surgery.

STUDY DESIGN

Randomized, placebo-controlled, blinded animal study.

SETTING

Animal laboratory.

SUBJECTS AND METHODS

Forty-two male New Zealand rabbits underwent bilateral 3-mm punch resection of the concha nasalis ventralis. The animals were divided into 3 groups: saline, late steroid, and early steroid. The saline group received saline drops, the late steroid group received saline drops for 7 days followed by intranasal mometasone furoate 50 µg/nostril/d, and the early steroid group received intranasal mometasone furoate (same dose) starting on postoperative day 1. The animals were sacrificed on postoperative days 10 and 21. Left nasal specimens were examined histopathologically with hematoxylin-eosin and matrix metalloproteinase-9 (MMP-9) stains. Right nasal specimens were examined with high-performance liquid chromatography, and hydroxyproline levels were measured as mg/g in wet tissue.

RESULTS

Late steroid and early steroid groups were similar with regard to MMP-9 staining on days 10 and 21. On day 10, the early steroid group revealed significantly intense MMP-9 staining when compared with the saline group, and the late steroid and early steroid groups revealed significant fibrosis when compared with the saline group. Hydroxyproline levels were similar in all groups on day 10. The early steroid group revealed significantly higher hydroxyproline levels when compared with the late steroid group on day 21.

CONCLUSION

Our findings showed that early intranasal steroid administration after sinus surgery in an animal model has no detrimental effects with regard to wound-healing parameters.

Dual Inhibition of Wound Healing and Oxidative Process by Montelukast in Experimental Colon Anastomoses

Background. The authors aimed to investigate the effects of montelukast (ML) on the experimental rat colon anastomosis. Methods. A total of 80 Wistar albino rats were divided into 4 groups: sham-operated, colon anastomosis, and colon anastomosis with oral administration (OAML) and rectal administration of 10 mg/kg/d ML (RAML). Anastomotic bursting pressure, anastomotic hydroxyproline contents, malondialdehyde (MDA), glutathione (GSH), glutathione peroxidase (GPX), and superoxide dismutase (SOD) levels, and the expressions of Ki-67, vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF) with immunohistochemistry were assessed on postoperative day 5. Results . Anastomotic bursting pressures and bFGF expressions were not changed, whereas tissue hydroxyproline concentrations and MDA levels and the expressions of Ki-67 and VEGF were significantly decreased, and GSH, GPX, and SOD levels were significantly increased in the OAML and RAML groups. Conclusion. ML causes impairment of wound healing without altering the anastomosis bursting pressure and reverses the oxidative damage of the colon anastomoses in rats.

The effect of prophylactic dose of a low molecular weight heparin on skin wound healing of rats

PURPOSE: To investigate the effect of prophylactic dose of a low molecular weight heparin, enoxaparin, on skin wound healing of rats. METHODS: Forty rats were used for the study. Rats were randomly assigned to two equal groups. Experimental group received prophylactic dose of enoxaparin. Physiologic saline was administered to the control group. Parameters of wound healing of experimental and control groups were compared. For comparison of the groups in terms of fibrosis, vascularization, inflammation, epithelization, and tensile strength test (Newton). Mann-Whitney-U test was used because variables were categorical data (fibrosis, vascularization, inflammation and epithelization). Differences between groups were analyzed with independent samples t-test (tensile strength). Significance was set at p<0.05. RESULTS: Skin wound of the experimental group presented tensile strength significantly decreased (p<0.001), histopathologic examination revealed a significant (p<0.001) delayed epithelization and decreased in fibrosis, vascularization, inflammation (p<0.001) in the experimental group. CONCLUSION: Enoxaparin delay wound healing by decreased inflammatory cells, fibroblast contents and their products (growth factors), and by promoted hemorrhage.