World Health Organization: In the presence of drains, does prolonged antibiotic prophylaxis prevent SSI?

One discussion this week included surgical drains and antibiotic PPX.


Reference: World Health Organization. Summary of a systematic review on antimicrobial prophylaxis in the presence of a drain and wound drain removal. WHO Surgical Site Infection Prevention Guidelines, Web Appendix 27 (30p.).

Summary: In the WHO SSI prevention guidelines, one of the PICO questions addressed is:

In the presence of drains, does prolonged antibiotic prophylaxis prevent SSI?

  • Population: inpatients and outpatients of any age undergoing a surgical
    operation (any type of procedure) with the presence of postoperative drainage
  • Intervention: prolonged antibiotic prophylaxis postoperatively
  • Comparator: single-dose antibiotic prophylaxis (or repeated intraoperatively
    according to the duration of the operation)
  • Outcomes: SSI, SSI-attributable mortality

Their findings are quoted below:

Seven RCTs were identified with an SSI outcome comparing prolonged antibiotic prophylaxis in the presence of a wound drain vs. single-dose perioperative prophylaxis, possibly repeated intraoperatively according to the duration of the procedure. The number of days for antibiotic prophylaxis prolongation in the postoperative period varied among studies. Three studies prolonged antibiotic administration until the wound drain was removed. In the remaining trials, patients continued intravenous administration for 3 or 5 days. Included patients were adults undergoing several types of surgical procedures (general surgery, kidney transplantation, and pilonidal sinus surgery). One trial evaluated whether prolonged antibiotic prophylaxis reduced the risk of infectious complications for patients undergoing elective thoracic surgery with tube thoracostomy. The antibiotic was continued for 48 hours after the procedure or until all thoracostomy tubes were removed, whichever came first.

Among the 7 RCTs, 6 studies showed no statistically significant difference between prolonged antibiotic prophylaxis in the presence of a wound drain vs. perioperative prophylaxis alone. Only one study reported that prolonged antibiotic prophylaxis reduced the risk of SSI. A meta-analysis of the 7 RCTs showed no statistically significant difference between the effect of prolonged antibiotic prophylaxis in the presence of a wound drain and perioperative prophylaxis alone for the risk of SSI (OR: 0.79; 95% CI: 0.53 –1.20]).

Overall, a low quality of evidence shows that prolonged antibiotic prophylaxis in the presence of a wound drain has neither benefit nor harm in reducing the SSI rate when compared to perioperative prophylaxis alone (single dose before incision and possible intraoperative additional dose/s according to the duration of the operation).

Risk of postoperative wound infections in neck dissections

One discussion this week focused on complications after neck dissections.


Reference: Man LX, Beswick DM, Johnson JT. Antibiotic prophylaxis in uncontaminated neck dissection. Laryngoscope. 2011 Jul;121(7):1473-1477. doi:10.1002/lary.21815.

Summary: Man et al (2011) performed a retrospective chart review of 273 uncontaminated neck dissections in order to identify risk factors for postoperative wound infections and to describe the outcomes of antibiotic prophylaxis use. Only 15%

Wound infection was not associated with age, sex, tobacco and alcohol use, history of head/neck surgery, history of radiation/chemotherapy, or number of drains placed during surgery.

Wound infection was independently associated with longer operative time, local/pedicled flap closure and radical or extended neck dissection (p.1474).

Their results for risk of wound infection by type of dissection are below. All 9 wound infections occurred in those receiving intraoperative antibiotics only (4) or intra- and postoperative antiobiotics (5).

neck dissection type

Additionally, this study found that antibiotics are prescribed more frequently to older patients, possibly because they are perceived as less healthy (p.1475). Patients requiring more extensive operations are at a higher risk of postoperative infection, as are those who undergo an operation involving the re-positioning of the patient’s head thus exposing the surgical field (p.1476). The under-reporting of postoperative complications in outpatient settings may also contribute to an underestimate of wound infection.

This review was not able to confirm or support the use of antibiotic prophylaxis in uncontaminated neck dissection significantly lowers the risk of infection. Still, the authors recommend its use “for more extensive lymphadenectomy procedures including radical neck dissection, extended neck dissection, or those requiring longer operative time” (p.1477).