Table 3.

Summary of recommendations

1. Definition, epidemiology, and risk factors of SSI

(1) Surgical site infection is defined as an infection that involves the skin and subcutaneous tissue of the incision (superficial incisional) and/or the deep soft tissue (for example, fascia, muscle) of the incision (deep incisional) and/or any part of the anatomy other than the incision that was opened or manipulated during an operation (organ/space)

(2) The incidence of surgical site infection after gastrointestinal surgery was 9.6% according to the Japan Nosocomial Infections surveillance. The incidence of SSI is highest after esophageal surgery, followed by rectal surgery and hepatobiliary surgery (3) The risk factors for surgical site infection are ASA, wound class, prolonged operation time, diabetes, obesity, hyponutritional status, history of smoking, and intraoperative blood transfusion

2. Diagnosis criteria, surveillance, and causal bacterium of SSI

(1) The criteria suggested by the Centers for Disease Control and Prevention (CDC)/National Healthcare Saftety Netowrk (NHSN) are used for the diagnosis of SSI. In Japan, some of these criteria have been modified slightly (2) Some reports suggest that the incidence of SSI after gastrointestinal surgery decreases with surveillance. Surveillance is necessary to assess the true incidence of SSI (D, Consensus) (3) Surveillance for more than 30 days after surgery is necessary, including for discharged patients (C, Consensus). It is preferable that the surveillance include many examination methods such as bacterial culture in combination with surveillance by an infection control team (ICT) for evaluation (D, Consensus) (4) In Japan, a surveillance system such as JANIS and JHAIS report the latest detection methods. Reference to these data for each surgical procedure is recommended 3. Preoperative management of SSI (1) In digestive surgery, the incidence of SSI in patients with known nasal carriage of S. aureus may be high (2) Preoperative decolonization may be useful for preventing SSI in patients who are known nasal carriers of S. aureus (C, 2a). However, universal decolonization without screening is not recommended, to prevent the spread of resistance (B, 4). Candidacy for screening of S. aureus carriage should be determined based on the local epidemiology in the hospital, the patient’s risk factors for S. aureus infection, and the surgical procedure to be performed (3) Although it may be desirable to give effective antibiotic prophylaxis to patients carrying resistant bacteria, there is no clear foundation to recommend it (D, 3) (4) Since patients with preoperative malnutrition who undergo digestive operations have a high incidence of SSI, the committee recommends that the malnutrition status should be improved before surgery (B, 2a) (5) It is not effective to administer enhanced nutritional formulas before surgery for the purpose of preventing SSI in non-malnourished patients who undergo digestive operations (B, 3) (6) Preoperative smoking is a high-risk factor for SSI (B). Patients who discontinue smoking for 1 month before surgery may decrease their risk of SSI (C, 2a) (7) Preoperative regular alcohol consumption is a risk factor for SSI (C). The effectiveness of abstinence from alcohol to prevent SSI is not clearly indicated, but we suggest preoperative abstinence (D, 2b) (8) Long-term or high-dose steroids are risk factors for SSI (C). The administration of immunomodulators and biologics before surgery is not a risk factor for SSI (C). However, the effect of reducing these drugs on SSI incidence has not been studied. Reduction or withdrawal of these drugs should be planned based on the original disease (D) (9) Preoperative mechanical bowel preparation (MBP) alone does not appear to have a preventive effect on SSI (A). However, MBP with oral antibiotics added (OAMBP) is recommended since it may have a preventative effect on SSI (B, 2a) (10) Preoperative cleansing of the skin with chlorhexidine gluconate has no effect on preventing SSI (B, 4) (11) It has been recommended to shave to prevent SSI, and not to do so (A, 5). There is no difference in the incidence of SSI between clipper hair removal, no hair removal, or using hair depilation cream (B) 4. Prophylactic antibiotics (1) Treatment with prophylactic antibiotics is considered beneficial in gastrointestinal surgery because of its effectiveness in the prevention of SSIs after laparoscopic cholecystectomy (A, 2a) and inguinal hernia surgery (B, 2a) (2) Although evidence is limited, administration within 60 min before the surgical incision is preferred (D, 2b) (3) No high-quality studies have shown that the intraoperative re-administration of prophylactic antibiotics reduces SSI incidence, and the utility of re-administration is not known. Therefore, there is no basis for recommending when re-administration is appropriate (C) (4) In patients undergoing elective gastrectomy for gastric cancer when prophylactic antibiotics were administered only before surgery (including patients given additional intraoperative treatment when surgery exceeded 3 h), there was no increase in SSI incidence compared with those who also received prophylactic antibiotic treatment after surgery. For this reason, only administration before surgery (including additional intraoperative treatment when surgery exceeds 3 h) is recommended (B, 2a). Evidence of the duration of prophylactic antibiotic treatment in elective colectomy for colorectal cancer is limited, and at this point, the difference in the benefit of administration only before surgery (including additional intraoperative treatment when surgery exceeds 3 h) and administration both before and after surgery is unknown (C, 3). Note that this analysis focuses mainly on laparotomy data, and laparoscopic surgery is a topic for future investigation 5. Intraoperative management (1) Surgical hand scrubbing and rubbing exhibit are equally effective for SSI prevention. Either method is acceptable but should be performed appropriately (A, no recommendation) (2) The panel recommends alcohol-based antiseptic solutions with chlorhexidine gluconate for surgical site skin preparation for patients undergoing gastrointestinal surgical procedures (B, 2a) (3) The effectiveness of adhesive drapes in preventing SSI is unclear (C, 3) (4) The use of wound protector devices, especially the double-ring wound protector device used in gastrointestinal surgical procedures, reduces the rate of SSI (A, 2a) (5) We suggest the use of double-gloving during surgery to address safety concerns since glove perforation may cause occupational exposures, injuries, or infections (A, 2b) (6) The value of changing instruments during surgery for preventing SSI is unclear due to the lack of evidence; hence, we do not actively recommend this practice. However, it is recommended to change instruments to avoid the use of potentially dirty or contaminated surgical operations (D, 2b) (7) We recommend the use of antimicrobial-coated sutures for preventing SSI during digestive surgery (B, 2a) (8) We recommend wound irrigation, especially with high pressure, for preventing SSI (C, 2a). However, we cannot provide a recommendation for wound irrigation with disinfectant, antibiotics, or electrolyzed acidic aqueous solution due to the lack of evidence (D, 3) (9) We do not recommend peritoneal lavage for preventing SSI due to the lack of evidence (D, 3) (10-1) Drain placement after surgery for gastric cancer did not show any benefit for SSI prevention. Drain placement is not necessary because mortality and complication rates are also low (B, 3) (10-2) Complications, SSI incidence and mortality are similar with or without drains after laparoscopic cholecystectomy, but the operation time was shortened with non-drainage. Therefore, drain placement is not required (A, 4) (10-3) The absence of a drain after hepatectomy without biliary reconstruction tends to have a lower SSI rate, less ascites, and shorter hospitalization. Therefore, the committee recommended that drain placement after hepatectomy was unnecessary. (A, 4) (10-4) SSI after pancreatoduodenectomy tends to be higher in the no-drain group, and some studies have been discontinued due to increased mortality rates, so it is recommended to use a drain (B, 2b). As far as duration of the drain placement, the committee recommended that it be removed early according to the criteria for postoperative pancreatic juice and that patients should be selected carefully (10-5) No drain is preferable after appendectomy for preventing SSI. Drain placement may increase the incidence of complications and mortality. Therefore, we do not recommend drain placement after appendectomy. (B, 4) (10-6) In colon surgery, drain placement is unnecessary in the prevention of SSI (A, 4). The clinical benefit of the drain placement is unclear, and it might be unnecessary. On the other hand, drain placement could be considered in specific cases when it might contribute to reducing severe complications (A, 3) (10-7) Although subcutaneous drain placement may reduce the incidence of SSI, it is necessary to consider the indications for appropriate cases, methods, and duration. (B, 3) (11-1) Subcutaneous suturing using absorbed materials is recommended. (B, 3) (11-2) Continuous sutures tended to result in less wound dehiscence and fewer wound infections than interrupted sutures for subcutaneous suturing after gastroenterological surgery. Therefore, continuous sutures rather than interrupted sutures are recommended for subcutaneous suturing (B, 2a). In fascia closure, incidences of SSI and wound hernia did not differ between continuous sutures and interrupted sutures. Therefore, either method can be used (B, 3) (11-3) Subcutaneous sutures using absorbable materials do not reduce the incidence of SSI versus skin closure using a stapler. However, it is recommended for cosmetic purposes and patient satisfaction (B, 2b) (11-4) The rates of SSI and wound dehiscence associated with bioadhesives for primary wound closure were comparable to those of sutures alone. Bioadhesives may improve cosmetic results and shorten operation time in primary wound closure after laparoscopic surgery (C, 3) 6. Perioperative management (1) Implementation of an early recovery program is recommended to reduce the incidence of SSI in patients undergoing digestive surgery, as well as for shortening the length of hospital stay and accelerating the recovery of gut function (A, 2a). However, it remains unclear which components of the program are optimal for SSI prevention in various types of digestive surgery (2) Preoperative carbohydrate loading does not prevent SSI after digestive surgery. Therefore, implementation of preoperative carbohydrate loading prevention is not recommended for SSI prevention (A, 3) (3) A blood glucose level of less than 150 mg/dL is desirable because strict blood glucose control during the postoperative period reduces the incidence of SSI significantly in digestive surgery patients with and those without diabetes mellitus (B, 2b). On the other hand, blood glucose should be monitored closely because of the inherent risk of a hypoglycemic event (4) There are no guidelines on whether perioperative oral hygiene contributes to the prevention of SSI in gastrointestinal surgery because of the lack of evidence (D). On the other hand, perioperative oral care may help to prevent postoperative pneumonia after esophagectomy (5) Intraoperative warming for maintaining normothermia is recommended for SSI prevention. (B, 2a) (6) High oxygen concentrations (FIO2 of 0.8) during and within 2–6 h after colorectal surgery may reduce the risk of SSI (B, 3). However, high concentrations of oxygen also have adverse effects such as absorption atelectasis and oxygen toxicity. Furthermore, the safety of high oxygen concentrations during long operations is not supported. The indication for high FIO2 should be evaluated carefully (7) Although early postoperative oral and enteral feeding does not reduce the risk of SSI (B), it is recommended because of other benefits such as shortening the hospital stay 7. Wound management (1) It is preferable to use protective wound dressings for relatively large incisional wounds after abdominal surgery, rather than covering them with gauze (B, 2b) (2) Although negative-pressure wound therapy at primary closure during abdominal surgery may reduce incisional SSI, the indications and costs need to be considered (B, 3)