Objective: We investigated the incidence of surgical site infection (SSI) following emergency abdominal surgery (EAS) in China and further explored its risk factors, providing a reference for preventing and controlling SSI after EAS. Methods: This was an observational study. Data of patients who had undergone EAS and been enrolled in the Chinese SSI Surveillance Program during 2018-2021were retrospectively analyzed. All included patients had been followed up for 30 days after surgery. The analyzed data consisted of relevant patient characteristics and perioperative clinical data, including preoperative hemoglobin, albumin, and blood glucose concentrations, American Society of Anesthesiologists (ASA) score, grade of surgical incision, intestinal preparation, skin preparation, location of surgical site, approach, and duration. The primary outcome was the incidence of SSI occurring within 30 days following EAS. SSI was defined as both superficial and deep incisional infections and organ/space infections, diagnoses being supported by results of microbiological culture of secretions and pus. Secondary outcomes included 30-day postoperative mortality rates, length of stay in the intensive care unit (ICU), duration of postoperative hospitalization, and associated costs. The patients were classified into two groups, SSI and non-SSI, based on whether an infection had been diagnosed. Univariate and multivariate logistic regression analyses were performed to identify risk factors associated with SSI following EAS. Results: The study cohort comprised 5491 patients who had undergone EAS, comprising 3169 male and 2322 female patients. SSIs were diagnosed in 168 (3.1%) patients after EAS (SSI group); thus, the non-SSI group consisted of 5323 patients. The SSIs comprised superficial incision infections in 69 (41.1%), deep incision infections in 51 (30.4%), and organ or space infections in 48 (28.6%). Cultures of secretions and pus were positive in 115 (68.5%) cases. The most frequently detected organism was Escherichia coli (47/115; 40.9%). There were no significant differences in sex or body mass index between the SSI and non-SSI groups (both P>0.05). However, the proportion of individuals aged 60 years or older was significantly greater in the SSI than in the non-SSI group (49.4% [83/168] vs. 27.5% [1464/5323), χ2=38.604, P<0.001). Compared with the non-SSI group, the SSI group had greater proportions of patients with diabetes (11.9% [20/168] vs. 4.8% [258/5323], χ2=16.878, P<0.001), hypertension (25.6% [43/168] vs. 12.2% [649/5323], χ2=26.562, P<0.001); hemoglobin <110 g/L (27.4% [46/168] vs. 13.1% [697/5323], χ2=28.411, P<0.001), and albuminemia <30 g/L (24.4% [41/168] vs. 5.9% [316/5323], χ2=91.352, P<0.001), and a reduced rate of preoperative skin preparation (66.7% [112/168] vs. 75.9% [4039/5323], χ2=7.491, P=0.006). Furthermore, fewer patients in the SSI group had preoperative ASA scores of between one and two (56.0% [94/168] vs. 88.7% [4724/5323], χ2=162.869, P<0.001) in the non-SSI group. The incidences of contaminated and infected incisions were greater in the SSI group (63.1% [106/168] vs. 38.6% [2056/5323], χ2=40.854, P<0.001). There was a significant difference in surgical site distribution between the SSI and non-SSI groups (small intestine 29.8% [50/168] vs. 10.6% [565/5323], colorectal 26.2% [44/168] vs. 5.6% [298/5 323], and appendix 24.4% [41/168] vs. 65.1% [3465/5323]) χ2=167.897, P<0.001), respectively. There was a significantly lower proportion of laparoscope or robotic surgery in the non-SSI group (24.4 % [41/168] vs. 74.2% [3949/5323], χ2=203.199, P<0.001); the percentage of operations of duration less than 2 hours was significantly lower in the SSI than non-SSI group (35.7% [60/168] vs. 77.4% [4119/5323], χ2=155.487, P<0.001). As to clinical outcomes, there was a higher 30-day postoperative mortality rate (3.0%[5/168] vs. 0.2%[10/5323], χ2=36.807, P<0.001) and higher postoperative ICU occupancy rate (41.7% [70/168] vs. 19.7% [1046/5323], χ2=48.748, P<0.001) in the SSI group. The median length of stay in the ICU (0[2] vs. 0[0] days, U=328597.000, P<0.001), median total length of stay after surgery (16[13] vs. 6[5] days, U=128146.000, P<0.001), and median hospitalization cost (ten thousand yuan, 4.7[4.4] vs. 1.7[1.8], U=175965.000, P<0.001) were all significantly greater in the SSI group. Multivariate logistic regression analysis revealed that the absence of skin preparation before surgery (OR=2.435,95%CI: 1.690-3.508, P<0.001), preoperative albuminemia <30 g/L (OR=1.680, 95%CI: 1.081-2.610, P=0.021), contaminated or infected incisions (OR=3.031, 95%CI: 2.151-4.271, P<0.001), and laparotomy (OR=3.436, 95% CI: 2.123-5.564, P<0.001) were independent risk factors of SSI. Operative duration less than 2 hours (OR=0.465, 95%CI: 0.312-0.695, P<0.001) and ASA score of 1-2 (OR=0.416, 95% CI: 0.289-0.601, P<0.001) were identified as independent protective factors for SSI. Conclusions: It is important to consider the nutritional status in the perioperative period of patients undergoing EAS. Preoperative skin preparation should be conducted and, whenever possible, laparoscope or robot-assisted surgery. Duration of surgery should be as short as possible while maintaining surgery quality and improving patient care.
目的： 调查中国急诊腹部手术（EAS）后发生手术部位感染（SSI）的情况，进一步探讨其风险因素，为EAS后防控SSI的出现提供参考依据。 方法： 采用观察性研究的方法。对国家SSI监测网2018—2021年期间前瞻性录入接受EAS的患者信息数据进行回顾性分析，所有患者随访至术后30 d。分析数据包括患者的一般资料，围手术期相关临床数据包括术前血红蛋白和白蛋白及血糖水平、美国麻醉医师协会（ASA）评分、手术切口等级、是否肠道准备及其方式、是否备皮、手术部位、手术方式以及手术时间等资料。主要结局指标为EAS术后30 d内SSI的发生情况，包括SSI发生率、感染类型［浅部切口感染、深部切口感染和器官（腔隙）感染］以及分泌物及脓液培养结果；次要结局指标为术后30 d内病死率、术后重症监护室（ICU）入住率和入住时间、术后总住院时间以及住院费用。依据是否发生感染，将患者分为SSI组和非SSI组，采用单因素及多因素logistic回归分析EAS后SSI发生的风险因素。 结果： 共纳入5 491例接受EAS的患者，其中男性3 169例，女性2 322例。168例（3.1%）EAS术后发生SSI（SSI组），非SSI组患者5 323例。SSI组中，浅部切口感染69例（41.1%），深部切口感染51例（30.4%），器官（腔隙）感染48例（28.6%）；分泌物及脓液培养结果阳性者115例（68.5%），其中大肠埃希菌检出率最高为40.9%（47/115）。SSI组与非SSI组比较，性别及体质指数差异无统计学意义（均P>0.05）；但SSI组年龄≥60岁者的比例［49.4%（83/168）比27.5%（1 464/5 323），χ2=38.604，P<0.001］、伴有糖尿病和高血压患者的比例［11.9%（20/168）比4.8%（258/5 323），χ2=16.878，P<0.001；25.6%（43/168）比12.2%（649/5 323），χ2=26.562，P<0.001］以及术前血红蛋白<110 g/L者［27.4%（46/168）比13.1%（697/5 323），χ2=28.411，P<0.001］和白蛋白<30 g/L者［24.4%（41/168）比5.9%（316/5 323），χ2=91.352，P<0.001］比例均偏高；术前备皮占比偏低［66.7%（112/168）比75.9%（4 039/5 323），χ2=7.491，P=0.006］；术前ASA评分1~2分者比例同样偏低［56.0%（94/168）比88.7%（4 724/5 323），χ2=162.869，P<0.001］；手术污染和感染切口的比例高［63.1%（106/168）比38.6%（2 056/5 323），χ2=40.854，P<0.001］；SSI组与非SSI组手术部位比较，小肠29.8%（50/168）比10.6%（565/5 323），结直肠26.2%（44/168）比5.6%（298/ 5 323），阑尾24.4%（41/168）比65.1%（3 465/5 323），差异有统计学意义（χ2=167.897，P<0.001）；腹腔镜或机器人手术比例明显低于非SSI组［24.4%（41/168）比74.2%（3 949/5 323），χ2=203.199，P<0.001］；手术持续时间<2 h患者的比例较低［35.7%（60/168）比77.4%（4 119/5 323），χ2=155.487，P<0.001］。而在临床结局上，与非SSI组比较，SSI组术后30 d病死率更高［3.0%（5/168）比0.2%（10/5 323），χ2=36.807，P<0.001］，术后ICU入住率也高［41.7%（70/168）比19.7%（1 046/5 323），χ2=48.748，P<0.001］，ICU中位住院时间［0（2）d比0（0）d，U=328 597，P<0.001］、术后中位总住院时间［16（13）d比6（5）d，U=128 146.000，P<0.001］和中位住院费用［4.7（4.4）万元比1.7（1.8）万元，U=175 965.000，P<0.001］均显著增加。多因素logistic回归分析显示，术前未备皮（OR=2.435，95%CI：1.690~3.508，P<0.001）、术前白蛋白<30 g/L（OR=1.680，95%CI：1.081~2.610，P=0.021）、污染或感染切口（OR=3.031，95%CI：2.151~4.271，P<0.001）和开腹手术（OR=3.436，95%CI：2.123~5.564，P<0.001）是发生SSI的独立危险因素；手术持续时间<2 h（OR=0.465，95%CI：0.312~0.695，P<0.001）及ASA评分1~2分（OR=0.416，95%CI：0.289~0.601，P<0.001）是SSI的独立保护因素。 结论： 针对接受EAS的患者，在围手术期应重点关注患者的营养状态，做好术前皮肤准备，尽量选择腹腔镜或机器人辅助的手术方式，在保证手术质量的前提下，尽可能缩短手术时间，对于切口污染或感染严重的患者应加强护理。.