Duration of prophylactic antibiotics
By Laura J. Prokuski, MD
Surgical site infection is a problem that has recently come under increased scrutiny. The U.S. Centers for Disease Control and Prevention (CDC) estimates that approximately 500,000 surgical site infections occur annually in the United States. Surgical site infections are a major cause of increased health care costs, as well as patient morbidity and mortality.1
An orthopaedic surgical site infection can lead to an extended hospitalization and prolonged antimicrobial use. True bone infection is difficult to eradicate. Infected and devitalized bone must be debrided. Implants are commonly removed to eradicate a nonviable biofilm where organisms can evade antibiotics. After the infection is controlled, skeletal reconstruction is often required. Antimicrobials must be given for a prolonged period of time to control the contamination. The prolonged administration of antibiotics magnifies their adverse effects, including allergic reactions, organ toxicity and bone marrow suppression.
Perioperative antibiotic prophylaxis is effective in reducing the rate of surgical site infections in orthopaedic surgery, particularly in joint replacements and closed fracture care. Optimal prophylaxis requires that a safe, effective antimicrobial be administered on a timely basis that allows effective levels in tissue during the procedure and that the antimicrobial be discontinued when the patient is no longer receiving a benefit.
However, errors in the use of prophylactic antibiotic occur frequently. Selection of the correct antibiotic, appropriate timing of its administration and the correct duration of its use are important in preventing surgical site infections, while minimizing side effects such as toxicity and antibiotic-resistance in local organisms.
The selection of an antimicrobial agent should take into account the common organisms related to particular surgical site infections, duration of action, antimicrobial spectrum, adverse reactions and cost. In orthopaedic surgery, first- or second-generation cephalosporins such as cefazolin or cefuroxime are commonly used. (See “Selecting an appropriate prophylactic antibiotic agent,” Bulletin, June 2005.)
The antimicrobial should be administered within 60 minutes prior to incision to ensure adequate tissue concentrations at the operative site. Redosing during long procedures may be required to maintain tissue concentrations of the antimicrobial. (See “Timing of prophylactic antibiotics in TJA,” Bulletin, August 2005.)
The proper duration of antibiotics used in a prophylactic manner is usually short. The majority of published evidence demonstrates that continuing to administer antibiotic prophylaxis beyond wound closure is not necessary. Studies comparing single-dose prophylaxis to multiple-dose prophylaxis have not shown any benefit from the additional doses. Limiting the administration of antibiotics to within the first day after surgery promotes cost containment and limits the opportunity for antibiotic toxicity and the development of antibiotic resistance in local organisms.
No evidence exists that continuing prophylactic antibiotics until all catheters and drains have been removed will lower infection rates.1 In total joint arthroplasty and hip fracture surgery, drain use is controversial. Drains have been associated with infection, retained foreign bodies and soft tissue problems. Over time, there is increased bacterial colonization of the drain tip and migration of skin flora into the wound.2-4 The current recommendation by the Centers for Medicare and Medicaid Services and CDC’s Surgical Infection Prevention Project is to discontinue the antimicrobial agent within 24 hours postoperatively.1
The use of prophylactic antibiotics has been proven to decrease the rate of surgical site infections in elective orthopaedic surgery cases. The selection of the correct antibiotic and timing its administration to ensure adequate tissue concentrations during the procedure are important factors in the efficacy of these agents. The duration of antimicrobial use should not exceed 24 hours after the incision is made.
Laura J. Prokuski, MD, is an assistant professor in the department of orthopaedics and rehabilitation at the University of Wisconsin Hospital and a member of the AAOS Infections Committee. She can be reached at email@example.com
1. Bratzler DW and Houck PM for the Surgical Infection Prevention Guidelines Writers Workshop. Antimicrobial prophylaxis for surgery: an advisory statement from the National Surgical Infection Prevention Project. Clin Infect Dis 2004; 38: 1706-15.
2. Drinkwater CJ and Neil MJ. Optimal timing of wound drain removal following total joint arthroplasty. J Arthroplasty 1995; 10(2): 185-9.
3. Willett KM, Simmons CD, Bentley G. The effect of suction drains after total hip replacement. J Bone Joint Surg 1988; 70B(4): 607-10.
4. Cobb JP. Why use drains? J Bone Joint Surg 1990; 72B(6): 993-5.