Evaluation of 3 Alcohol-based Agents for Presurgical Skin Preparation in Mice

Preoperative skin asepsis protocols using chlorhexidine versus povidone-iodine in veterinary surgery: A systematic review and meta-analysis

OBJECTIVE

To provide a systematic assessment of the efficacy of preoperative skin asepsis using chlorhexidine versus povidone-iodine based protocols for surgical site infection (SSI) prevention in veterinary surgery.

STUDY DESIGN

Systematic meta-analytical review according to PRISMA-P guidelines.

SAMPLE POPULATION

Studies comparing preoperative skin asepsis protocols using chlorhexidine versus povidone-iodine in veterinary surgery identified by systematic search between 1990 and 2020.

METHODS

A search using MEDLINE/Pubmed, Web of Science and CAB Abstracts was performed, followed by secondary searches of Google Scholar, Proquest Dissertation and Theses, and relevant bibliographic articles. Primary and secondary outcome measures were the efficacy of skin asepsis protocols using chlorhexidine versus povidone-iodine on SSI incidence and skin bacterial colonization, respectively. A meta-analysis was performed with a random-effect model, with effect size calculated as risk ratio (RR) or mean standard deviation (MSD) with 95% CI. Statistical significance was set at P < .05.

RESULTS

Among 1067 publications that met the initial search criteria, 9 relevant studies were eligible for analysis. No difference in the incidence of postoperative SSI or skin bacterial colonization between preoperative asepsis protocols using chlorhexidine versus povidone-iodine was found. Insufficient information and detail were frequent among studies and precluded a clear assessment of bias.

CONCLUSION

This study showed that asepsis protocols using chlorhexidine were comparable to povidone-iodine in preventing postoperative SSI and reducing skin bacterial colonization.

CLINICAL SIGNIFICANCE

Given the limitations of the studies that were included in terms of both quality and quantity, more high-quality randomized controlled trials are needed to confirm these conclusions.

The Effect of Different Preoperative Depilation Ways on the Healing of Wounded Skin in Mice

Simple Summary

An increasing number of animals, including pets, may undergo surgery due to diseases or cesarean section nowadays. To reduce surgical site infection, hair removal is a necessary step before the surgical procedure because of the dense hair layer on the skin. However, previous studies showed that inappropriate hair removal methods might even increase surgical site infection rates. Although there are many commonly used preoperative depilation methods, it still has no detailed, unified selection criteria for animal preoperative hair removal. Therefore, we intend to provide a scientific and practical reference for veterinarians. To explore more specific details on whether depilation affects the condition of a surgical site, we established a skin wound model after the depilation step and then compared four commonly used hair-removal methods through morphological assessment and histopathological analysis. Ultimately, we concluded that the electric shaving method is the best method for preoperative depilation, followed by the depilatory cream method, and the sodium sulfide aqueous solution depilation method is the worst. We hope that the results of this study can provide useful reference points for veterinarians and researchers and help refine surgical procedures and maintain animal welfare.

Abstract

Hair removal is necessary before operating on animals with dense hair layers. To provide an appropriate hair removal method and maintain animal welfare, we introduced four commonly used depilation methods—namely, scissors shearing, electric shaving, depilatory cream, and sodium sulfide, and made systematic comparisons, instead of only examining one or two methods, as reported in the past. To further assess convenience and possible effects on skin wound healing, we performed a skin trauma model after depilation in C57BL/6J mice and recorded wound healing time. Meanwhile, the skin tissues around the wound were stained with H&E and Masson. The results showed that the wound contraction rate of the sodium sulfide group was significantly lower than other groups at different points in time. Furthermore, depilatory cream and sodium sulfide methods could induce a topical inflammatory response on the third day after the operation and delay the regeneration of collagen fibers. We concluded that sodium sulfide depilatory has a significant negative effect on wound healing. Depilatory cream is gentler, with mild skin irritation and symptoms of inflammation. The electric shaving method is more convenient and safer, and thus could be the best choice for preoperative depilation.

Using Waterless Alcohol-based Antiseptic for Skin Preparation and Active Thermal Support in Laboratory Rats

Rodents are frequently used for models that require surgical procedures. At our institution, laboratory rats are increasingly preferred for investigations of neurologic disorders, cardiovascular interventions, and assessment and treatment of addictive and depressive behaviors. For these types of studies, surgical preparations of the head and neck areas are necessary for catheterization and instrumentation. Based upon our former work in laboratory mice, we sought to improve rat surgery outcomes and confirm the efficacy of a waterless alcohol-based (WAB) antiseptic for skin disinfection prior to incision. In addition, we wanted to investigate whether active warming efforts improved perioperative body temperatures for rats to aid in return to consciousness. Prior to cranial surgical incision and placement in stereotactic equipment, rats were assessed after skin preparation with WAB and after thermal interventions, including prewarming cages for 30 min before anesthesia and delivery of warmed fluid (NaCl) supplementation. Core temperatures were recorded and aerobic culture swabs collected from surgical sites at multiple time points. As previously shown in mice, bacterial counts in rats were effectively diminished by WAB agents. Assessment of intraoperative body temperature trajectories did not identify appreciable differences between control rats and rats that were exposed to prewarming or warmed fluid supplementation or both. However, heavier male rats recovered more rapidly from isoflurane anesthesia than did lighter male and female rats. Although these thermal support measures did not significantly improve anesthetic recovery times in rats, animals warmed for 30 min trended toward a faster return to righting reflex after exposure to isoflurane. These findings confirm that WAB antiseptic is an acceptable option for skin preparation in rats and suggest that continued evaluation of thermal interventions remains of interest for improved outcomes in rat surgery.