Do Intra-incisional Subdermal Antibiotics Alter the Colony Count of P. Acnes
试验速览
- 阶段
- 早期 1 期
- 入组人数
- 20
- 主要终点
- Change in P.acnes colony count
研究概览
简要总结
The specific outcome is to determine whether the colony count of Propionibacterium acnes, one of the commonest causes of shoulder infection and not eradicated by conventional forms of surgical preparatory solutions and antibiotics, in a shoulder surgical wound will be altered by the use of subdermal cefazolin.
详细描述
Purpose The purpose of the study is to review if the subdermal injection of antibiotics intraoperatively reduces the bacterial load in the subcutaneous tissue during the course of an open shoulder operation.
Null Hypothesis There will be no change in the colony count of P.acnes following administration of subdermal antibiotics.
Justification. P. Acnes is the most common cause of shoulder infection. The incidence of post-operative shoulder joint infection varies from 4-18%. The P.acnes organism is a Gram positive, largely anaerobic but aerotolerant commensal of the deep skin follicles and standard skin preparation may inadequately penetrate the pilosebaceous follicles. It has also been shown in a study by Levy et al that 41.8% of patients had a positive biopsy or aspirate result for P.acnes prior to implantation of components. This study will determine whether intraoperative subdermal antibiotic administration reduces the bacterial load and in turn reduce the incidence of shoulder joint infection. Cefazolin has been chosen because cephalosporins and penicillins have the lowest minimum inhibitory concentration (MIC) against P.acnes. There is a lower incidence of allergy to cephalosporins than penicillins. This study has the potential to change clinical practice world wide.
Objectives The specific outcome is to compare the bacterial cell count on either side of a surgical wound and determine if subcutaneous antibiotics on a single side reduces subcutaneous cell counts over various time courses throughout the operation.
Research Method. Targeted recruitment is 20 patients in this pilot study. This figure has been arrived at after determining the power of the study, significance levels and the anticipated drop in P.acnes count colonisation after the use of local antibiotics. It is also a number that can be achieved rapidly, enabling us to assess whether there is an observed difference between the groups and thereby gauge the feasibility of a larger trial.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Prevention
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 90 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •age greater than or equal to 18
- •patients requiring deltopectoral approach and opening of joint capsule for primary shoulder surgery
排除标准
- •allergy to cefazolin or cephalosporins
- •tattoos over operative site
- •previous surgical site infections in either shoulder
- •revision surgical procedure
- •immunocompromised patients
研究组 & 干预措施
Subcutaneous cefazolin arm
A patient receiving a standard deltopectoral approach will have the planned incision site divided into thirds. This will produce 6 segments. Each segment will be biopsied using a commercially available dermatology punch and sent for colony count prior to local antibiotic infiltration. Cefazolin will be administered to one half of the incision only, into three segments. Following 60 minutes of operative time, the biopsies will be repeated and sent for colony count for comparison.
Cefazolin administered will be 100mg/mL in 3 aliquots for 3 site administrations leading to a total subcutaneous injection of approximately 900mg. There will be a one time administration of the antibiotics in a subcutaneous route.
干预措施: Cefazolin (Drug)
结局指标
主要结局
Change in P.acnes colony count
时间窗: Baseline tissue sampling prior to subcutaneous antibiotic administration, and tissue sampling 60 minutes after
Colony count before and 60 minutes after subcutaneous cefazolin administration
次要结局
未报告次要终点
研究者
William D Regan
Associate professor
University of British Columbia