Comparison of Mechanical Characteristics of Commonly Used Vaginal Packing Materials.

INTRODUCTION: Clinically, vaginal packing provides the benefit of hemostasis and is designed to prevent the formation of postoperative hematomas. Despite the common use of vaginal packing in pelvic surgery, there is limited data to indicate which material has the ideal characteristics for vaginal packing. MATERIALS AND METHODS: Three packing materials were used: DeRoyal(R) Fluftex (DeRoyal Industries, Inc., Powell, Tennessee), NHP Surgi-Pak vaginal packing (NHP Industries, Inc., City of Industry, California), and Curad(R) Plain Packing Strips (Medline Industries, Inc., Northfield, Illinois). A fluid with similar viscosity to human blood, defibrinated sheep's blood (Remel Laboratories, Nenexa Kansas) was used to saturate the materials. The primary outcome was the amount of fluid absorbance of each product in both the handpacked and unpacked state. The number of drops used to saturate each material were counted and converted to mL/g. Each product was tested three times and the results were measured by counting the number of drops needed to saturate the material in each experiment. Experiment: Three materials were obtained and conducted into two different experiments to test absorbance. The packed trial consisted of 0.1g of material and was compacted in a 146mm standard Pasteur pipette (Sigma-Aldrich Corp., St. Louis, Missouri). Droplets of sheep's blood were dispensed until each material had reached its capacity, which was determined by counting the last sequential drop received onto the respective material before the first of the fluid fell from the material into the collecting container. Trials were conducted three times per material and an average of the three trials was calculated. The second experiment tested 1g of each material unpacked and folded into eight layers. Droplets of blood were placed onto the material until each material leaked, which was defined again as the first fluid to fall from the material into the collecting container that it was suspended above. The number of drops needed to produce this effect was recorded. All droplets were counted and converted to mL/g. Standard deviation was calculated for each material in both experiments and an analysis of variance (ANOVA) single factor test was done. RESULTS: Three trials were conducted per material and there was a difference in absorbance between each packing material (p=0.02 packed, p=0.001 unpacked). Additionally, the plain packing strip absorbed the least amount of blood product in the packed and unpacked state compared to DeRoyal(R) Fluftex and NHP Surgi-Pak vaginal packing. The average absorbance of the packed materials was 7.7mL/g for DeRoyal(R) Fluftex, 9.8mL/g for NHP Surgi-Pak vaginal packing, and 7.5mL/g for the Curad(R) Plain Packing Strips. There was a standard deviation of 2.08 drops for DeRoyal(R) Fluftex, 3.51 drops for NHP Surgi-Pak vaginal packing, and 1.73 drops for Curad(R) Plain Packing Strips. Absorbance for DeRoyal(R) Fluftex unpacked was 8.2mL/g, NHP Surgi-Pak vaginal packing unpacked was 7.00mL/g, and Curad(R) Plain Packing Strips was 4.8mL/g. The standard deviation for the unpacked experiment was 29.02 drops for DeRoyal(R) Fluftex, 13.61 drops for NHP Surgi-Pak vaginal packing, and 15.59 drops for Curad(R) Plain Packing Strips. A p-value of less than .05 in a confidence interval of 95% was determined. CONCLUSION: Even though there are studies showing the clinical benefits of vaginal packing after a variety of gynecological surgeries, there is less known about the characteristics of the ideal material. Minimal foreign body reaction, decreased adherence to surgical scars, X-ray visualization, low cost, and easy availability are among the ideal characteristics of the presumed ideal material used for vaginal packing. In this study, we compared the absorbance between three commonly used materials and did not find any statistical differences. Further studies are needed to show the clinical benefits and mechanical characteristics of material used for vaginal packing. Due to the lack of a statistically significant difference in absorbance between the materials, evaluation of mechanical characteristics may be beneficial in determining an ideal vaginal packing product.