山下 千鶴

INTRODUCTION: This is a systematic review and meta-analysis of the efficacy of wound coverage using advanced dressings specifically for the prevention of surgical site infections (SSI) in gastrointestinal surgery, as part of the update of the SSI prevention guidelines of the Japan Society for Surgical Infection (JSSI). METHODS: After searching CENTRAL, PubMed, and ICHUSHI-Web in July 2024, we included randomized controlled trials (RCTs) comparing advanced dressings and standard dressings for surgical wounds in gastrointestinal surgery (PROSPERO No. CRD42024569084). Three authors independently screened the RCTs. We assessed the risk of bias and certainty of the body of evidence for the extracted data. The primary outcome was superficial SSI, and the secondary outcomes were length of postoperative hospital stay, costs, and allergy. This study was partially supported by the JSSI. RESULTS: A total of seven RCTs and 927 patients were included. The use of advanced dressings significantly lowered the risk of SSI compared to that associated with standard dressings (risk ratio: 0.54, 95% confidence intervals: 0.34-0.88). The certainty of the evidence was rated as moderate. According to the subgroup analysis, advanced dressings reduced the risk of SSI in colorectal surgery. Advanced dressings did not reduce the length of postoperative hospital stay or costs compared to that of standard dressings. Allergies were reported in only one patient using silver-impregnated dressings. CONCLUSION: The use of advanced dressings for primary wounds in gastrointestinal surgery was associated with a significantly lower risk of SSI than that associated with standard dressings.

BACKGROUND: Appropriate antibiotic prophylaxis is essential for preventing surgical site infections (SSI); however, the clinical benefit of intraoperative redosing remains unclear and controversial owing to insufficient reliable evidence. Therefore, we performed a systematic review and meta-analysis to assess the effectiveness of prophylactic antibiotic redosing in lengthy surgical procedures. METHODS: We systematically searched the PubMed, Cochrane Library, Web of Science, and Ichushi-Web databases for articles published until 31 December, 2023. We compared the incidence of SSI between patients receiving and not receiving intraoperative redosing of antibiotics in surgeries lasting ≥3 h. Subgroup analyses were conducted across study characteristics. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using the Mantel-Haenszel random effects model. The risk of bias was assessed using the ROBINS-I. RESULTS: Overall, seven observational studies involving 4,671 patients were included. Intraoperative antibiotic redosing significantly reduced the risk of SSI compared with non-redosing (OR = 0.65, 95% CI = 0.45-0.94, p = 0.02). Subgroup analyses showed that intraoperative redosing decreased SSI risk in studies with a minimum 4-h operative time, no postoperative antibiotic continuation, and a moderate risk of bias. However, the statistical heterogeneity of the analyses was high among the studies. CONCLUSIONS: Intraoperative redosing with prophylactic antibiotics during lengthy surgeries may be associated with a lower risk of SSI than non-redosing. Therefore, we recommend intraoperative redosing for surgeries lasting beyond 3-4 h to reduce the risk of infection. Further research is required to clarify the optimal redosing interval, which should be prioritized in future studies.

BACKGROUND: Polymyxin-B direct hemoperfusion (PMX-DHP) is an endotoxin adsorption column-based blood purification therapy. Since one of the most potent effects of PMX-DHP is blood pressure elevations, it may be the most effective when it is introduced at the time when the need for vasopressors is the greatest, which, in turn, may reduce mortality. METHODS: A multicenter retrospective study was conducted at 24 ICUs in Japan. In each ICU, the 20 most recent consecutive cases of septic shock treated with PMX-DHP were analyzed. The duration between the time of the peak vasopressive agent dose, expressed as the noradrenaline equivalent dose (NEq), and the time of PMX initiation was evaluated. The primary outcome was 28-day mortality, and a multivariable analysis was performed to investigate factors associated with mortality. RESULTS: A total of 480 septic shock patients were included in the analysis. Among all patients, the 28-day mortality group was older, more severely ill, and had a higher body mass index. The NEq peak and NEq on PMX-DHP initiation were both higher in deceased patients. Regarding the timing of PMX-DHP initiation from the NEq peak, -4 << 4 h had more survivors (229/304, 75.3%) than ≤-4 h (50/75, 66.7%) and ≥4 h (66/101, 65.4%) (p = 0.085). When -4 << 4 h was assigned as a reference, the timing of PMX-DHP initiation from the NEq peak of ≤-4 h had an odds ratio of 1.96 (1.07-3.58), p = 0.029, while ≥4 h had an odds ratio of 1.64 (0.94-2.87), p = 0.082 for 28-day mortality, in the multivariable regression analysis. A spline curve of the relationship between the probability of death and the timing of PMX-DHP initiation from the NEq peak showed a downward convex curve with a nadir at timing = 0. The odds ratios of the timing of PMX-DHP initiation other than -4 << 4 h were significantly higher in an older age, male sex, lower BMI, more severe illness, and higher oxygenation. CONCLUSIONS: The induction of PMX-DHP at the time of the peak vasopressor dose correlated with lower mortality. PMX-DHP is one of the options available for elevating blood pressure in septic shock, and its initiation either too early or late for shock peak may not improve the outcome.

BACKGROUND: Surgical site infections (SSIs) can affect mortality, morbidity, and medical costs. Although it has recently been reported that washing with antiseptic/antibiotic solution can prevent SSI in clean surgery, the clinical impact in gastrointestinal surgery is still uncertain. Therefore, we performed a systematic review and meta-analysis to evaluate the efficacy of antiseptic/antibiotic solution during wound irrigation or peritoneal lavage in gastroenterological surgery. METHODS: The database search used PubMed, MEDLINE, and Cochrane Library. The following inclusion criteria were set for the systematic review. 1) Studies comparing with or without antiseptic/antibiotic irrigation/lavage during gastrointestinal surgery. 2) Studies that described surgical site infections and adverse events. 3) Studies conducted after 2000. RESULTS: A total of 8 randomized controlled studies (RCTs) and 3 observational studies were included in this meta-analysis. Three RCTs of wound irrigation with povidone iodine (PVI) solution revealed no significant difference between the PVI and control groups [RR 1.41, 95% CI (0.92 to 2.17): p = 0.69]. Three RCTs of peritoneal lavage with antibiotic solution showed no significant difference between the interventional group and control groups [RR 0.39, 95% CI (0.10 to 1.55): p = 0.18]. Regarding other antiseptic or antibiotic solutions, the number of studies and participants were too small for evaluation. CONCLUSION: Wound irrigation and peritoneal lavage with antiseptic/antibiotic solution did not have enough efficacy for preventing SSI during gastroenterological surgery.