腹腔镜手术可以减少住院感染率

根据发表于美国肠胃道与内视镜外科医师学会2008年会并登载于4月号Surgical Endoscopy期刊的一篇回溯分析，相较于开放手术，腹腔镜手术可以减少50%的住院感染率和65%的再住院率；项分析的病患是接受胆囊切除术、阑尾切除术、子宫切除术。
　　
　　担任发表人的主要作者Andrew I. Brill医师向Medscape General Surgery表示，这些结果以及此一领域之前的研究，强力支持腹腔镜手术的好处，可以运用到研究中三项手术以外的其他手术，估计每年可减少美国170万件住院感染导致的100,000例死亡；Brill医师是旧金山加州太平洋医学中心的妇科微创主任。
　　
　　此外，Brill医师表示，该研究是首度检视在这些手术出院后30天内的感染；研究发现，40%的感染发生在出院后30天内；之前有关出院后感染的研究有限 ，主要是比较腹腔镜手术和开放手术的不确定风险。
　　
　　研究者回溯分析22间医院、11,662名手术住院病患的资料，使用院内感染标记( nosocomial infection marker，NIM)辨识住院和出院后发生的院内感染。
　　
　　NIM是电脑演算系统，可以确认微生物的院内感染存在，分辨病源和污染、辨识独立的复制品、暂时确认院内或社区感染病源；之前的多医院研究显示，NIM电脑演算侦测院内感染有86%的敏感性和98.5%的专一性。
　　
　　的研究中，腹腔镜或开放式胆囊切除术的病患占32.7%、阑尾切除术占24.0%、子宫切除术占 43.3%；利用感染源分析资料，包括泌尿道、伤口、呼吸道、血液以及其他；其他共变项，如性别、年纪、保险类型、住院复杂度、急诊住院、病例组合指标（case mix index）住院，均以单一变项和多变项逻辑回归分析。
　　
　　开放式手术的整体感染率是4.09%，腹腔镜手术是 2.11%；根据337名病患的399件NIMs资料，相较于开放手术，腹腔镜胆囊切除术和子宫切除术均可减少超过50%的院内感染整体风险(腹腔镜比开放式胆囊切除术减少66%；腹腔镜比开放式子宫切除术减少 52%：两者的P < .01)；至于腹腔镜和开放式阑尾切除术，在院内感染率风险则没有明显差异。
　　
　　交叉比较子宫切除术、胆囊切除术、阑尾切除术，与开放式手术相比，腹腔镜手术可以减少各类型的院内感染整体的风险比 (OR)：呼吸道感染减少 80%、血液感染减少 69%、伤口感染减少 59%、泌尿道感染39%、其他类型的院内感染减少48%。
　　
　　奥兰多市佛罗里达纪念医院骨盆健康中心主任、妇科外科主任Steven D. McCarus医师表示，必须呼吁的是减少开放式子宫切除术，因为增加了院内感染风险；McCarus医师并未参加此研究，由Medscape General Surgery邀请提出建议。
　　
　　McCarus医师表示，妇科和一般外科需持续微创方式，以改善病患的结果；这篇报告特别注明并强调女性病患的微创手术好处。
　　
　　虽然有27%的病患在出院之后发现有院内感染而再度住院，但相较于开放式手术，腹腔镜胆囊切除和子宫切除术可以减少65%的再度住院(P < .01)。
　　
　　Brill医师表示，藉由减少感染率，腹腔镜手术可以相当程度地减少健康照护体系用于院内感染的费用达数十亿美金；该研究也显示，相较于开放式手术，当病患接受腹腔镜胆囊移除和子宫切除术时，可以减少65%因院内感染的再住院率，这表示可以节省住院花费。
　　
　　本研究的限制包括，缺少一些潜在影响结果的资料，例如抗生素的使用、麻醉分数、伤口类型、身体质量指数、之前的住院史、心血管疾病或糖尿病以及免疫不全等共病症。
　　
　　Brill 医师表示，这模式中有一些明确的变项未被考量，包括校正共病症状况、疾病严重度、以及诊断相关的内因性限制；不过，此分析中的统计干扰因为样本数够大而消弭，研究期间使用的资料没有任何排除，单一变项和多变项分析的结果都一致。
　　
　　若论及研究的弱点，McCarus医师表示，因为缺乏一些资料以及没有校正病患的共病症而受到限制；不过，研究的强项在于从22间医院超过11,000名以上的住院病患资料进行分析。
　　
　　McCarus医师表示，资料分析适当的进行，比较腹腔镜与开放式胆囊切除术和子宫切除术的结论是明显的；这篇报告有其重要性，因为院内感染问题是全面性的；这鼓励我们这些医师继续研究以表达感染率和风险。
　　
　　除了降低院内感染，腹腔镜手术还有其他好处；不过，在选择这两种手术时要衡量潜在的伤害。
　　
　　Brill 医师表示，虽然腹腔镜手术可能会有伤害腹内脏器与构造的风险，但相较于开腹手术，腹腔镜手术可以提供比较好的美观效果、比较迅速的恢复、比较少的术后疼痛，以及适合门诊手术。
　　
　　McCarus医师表示，若未经训练，腹腔镜手术有其风险；腹腔镜手术须由有适当训练的医师执行才有好处，医师持续学习微创手术技术改善或改变，是达到最终目标的重要环节— 目标就是迅速恢复、减少住院天数、术后恢复较快速。
　　
　　至于其他研究，Brill医师建议将这项研究扩展到其他现在以开腹和腹腔镜方式进行的手术类型，例如结肠切除术；他也建议比较这两类型手术的花费，记住，院内感染会造成较高的花费。
　　
　　Brill医师结论表示，这类的回溯研究利用挖掘资料以提供比其他研究多的资讯，使得这些研究可以整合新治疗方式的实际影响，帮助确认需要手术之病患的最佳与最有效率的照护。
　　
　　Johnson & Johnson集团旗下的 Ethicon Endo-Surgery公司发展及行销微创手术与开放手术的进阶装置，并赞助此项研究；Brill医师和 McCarus医师都是Ethicon Endo-Surgery公司的谘询顾问。
　　
　　美国肠胃道与内视镜外科医师学会2008年会暨毕业后课程。发表于2008年4月12日。

Laparoscopic Surgery May Reduc

By Laurie Barclay, MD
Medscape Medical News

Laparoscopic surgery was linked to a 50% reduction in hospital-acquired infection rates and a 65% reduction in hospital readmissions vs open surgery, according to the results of a retrospective analysis presented recently at the Society of American Gastrointestinal and Endoscopic Surgeons 2008 Annual Scientific Session and published in the April issue of Surgical Endoscopy. This analysis was limited to patients undergoing cholecystectomy, appendectomy, or hysterectomy.

"These results, combined with previous research into this area, strongly suggest the benefits of laparoscopic surgery may apply to procedures beyond the 3 types included in this particular study to reduce the estimated 100,000 deaths associated with the 1.7 million hospital-acquired infections that occur annually in the [United States]," presenter and lead author Andrew I. Brill told Medscape General Surgery. Dr. Brill is director of minimally invasive gynecology at the California Pacific Medical Center in San Francisco.

"Additionally, this study is the first to examine infections specific to these procedures 30 days postdischarge," Dr. Brill said. "The study discovered that 40% of the infections identified occurred within 30 days after hospital discharge. Previous studies on postdischarge infections have been very limited, and it is likely that comparisons of laparoscopic and open surgeries have underestimated risks."

The investigators retrospectively analyzed data from 11,662 surgical admissions to 22 hospitals that used the nosocomial infection marker (NIM) to identify nosocomial infections occurring during hospitalization and postdischarge.

NIM is a computer algorithm that identifies the existence of nosocomial infections at the microbiological level, distinguishing likely pathogens from contaminants, identifying duplicate isolates, and temporally determining hospital- vs community-acquired pathogen acquisition. A previous multihospital study showed 86% sensitivity and 98.5% specificity of the NIM algorithm for detecting nosocomial infections.

In the present study, admission was for laparoscopic or open cholecystectomy in 32.7% of patients, for appendectomy in 24.0%, and for hysterectomy in 43.3%. Data were analyzed by source of infection, including urinary tract, wounds, respiratory tract, bloodstream, and others. The effect of certain potentially confounding variables, such as sex, age, insurance type, complexity of admission, admission through the emergency department, and hospital case mix index, was examined with single and multivariable logistic regression analyses.

Overall infection rates were 4.09% for open surgery and 2.11% for laparoscopic procedures. In analyses based on 399 NIMs identified in 337 patients, laparoscopic cholecystectomy and hysterectomy were each associated with a greater than 50% reduction in the overall odds of acquiring nosocomial infections compared with open surgery (66% reduction for laparoscopic vs open cholecystectomy; 52% reduction for laparoscopic vs open hysterectomy; P < .01 for each).

Laparoscopic and open appendectomy were not significantly different in terms of the odds of acquiring nosocomial infections.

Across hysterectomies, cholecystectomies, and appendectomies, laparoscopic surgery vs open surgery was associated with a reduction in the overall odds ratio (OR) for each type of nosocomial infection: an 80% reduction in the OR for respiratory tract infection, a 69% reduction in the OR for bloodstream infection, a 59% reduction in the OR for wound infection, a 39% reduction in the OR for urinary tract infection, and a 48% reduction in the OR for other types of nosocomial infections.

"A call to action must be heard to decrease open hysterectomy techniques, which have an increased nosocomial infection risk," said Steven D. McCarus, MD, chief of gynecological surgery and director of the Center for Pelvic Health at Florida Hospital Celebration in Orlando. Dr. McCarus was not involved with this study but was asked to provide independent commentary for Medscape General Surgery.

"Gynecologists and general surgeons will continue minimally invasive approaches to improve patient outcomes," Dr. McCarus said. "This paper especially endorses and emphasizes the benefits of minimally invasive surgery in the female patient."

Although 27% of patients found to have a nosocomial infection after discharge were readmitted to the hospital, laparoscopic cholecystectomy and hysterectomy were associated with a 65% reduction in readmissions for infections compared with open surgery (P < .01).

"By reducing the rate of infection, laparoscopic surgery has the potential to dramatically cut into the billions of dollars [in costs] incurred by the healthcare system due to hospital-acquired infections," Dr. Brill said. "The study also showed a 65% reduction in hospital readmissions for hospital-acquired infections when a patient underwent laparoscopic gallbladder removal and hysterectomy when compared to open surgery. This translates into cost savings for hospitals and payors."

Limitations of this study include absence of certain data that could potentially confound the results, such as antibiotic use, anesthesia scores, wound class, body mass index, prior hospitalization, and comorbidities of cardiovascular disease, diabetes mellitus, and immunodeficiency.

"There were definitely variables that were not considered in the model, including no adjustments for comorbid conditions, the severity of disease, and the intrinsic limits of present [diagnosis-related groups]," Dr. Brill said. "However, the statistical noise in this analysis is well balanced by the very large sample size, the use of all data during the time frame without any exclusions, and the fact that univariate and multivariate findings were consistent."

In terms of study weaknesses, Dr. McCarus agreed that the controls were limited by the absence of certain data and that there was no adjustment for patient comorbidities. However, a major strength was analysis of more than 11,000 admissions to 22 hospitals.

"Analysis of data was appropriately done, and conclusions were significant in comparing laparoscopic cholecystectomy and hysterectomy to their open counterparts," Dr. McCarus said. "Certainly this paper is an important one because of the associated nosocomial infection problem that is global. This encourages us as surgeons to continue additional research where we can address infection rates and risks."

In addition to potential reduction in nosocomial infections, laparoscopic surgery may confer other benefits over open surgery. However, potential harms should also be considered when choosing between these approaches.

"Whereas laparoscopic surgery carries the irreducible but small risk of injury to intraabdominal visceral and vascular structures, compared to laparotomy it provides superior cosmesis, more rapid recovery, less postoperative pain, and the option for outpatient surgery," Dr. Brill said.

"In untrained hands, laparoscopy has associated risks," Dr. McCarus agreed. "Laparoscopic surgery has benefits when performed by properly trained surgeons. A commitment on the part of the surgeon to learn and relearn minimally invasive techniques as technologies improve or change is paramount in reaching our endpoint — the endpoint being quicker recovery, decreased hospital stays, and faster recovery."

In terms of additional research, Dr. Brill recommends extending this research to other types of surgical procedures now routinely performed by both laparotomic and laparoscopic methods, such as colectomy. He also suggests investigating the comparative cost components of conventional vs laparoscopic surgery, keeping in mind the high costs related to nosocomial infections.

"This type of retrospective study utilizing data mining provides access to much more information than is available in other types of studies, making these studies integral in measuring the real-world impact of newer treatments and helping to determine the best and most efficient care for patients who need surgery," Dr. Brill concluded.

Ethicon Endo-Surgery, a Johnson & Johnson company that develops and markets advanced medical devices for minimally invasive and open surgical procedures, supported this study. Dr. Brill and Dr. McCarus are both consultants to Ethicon Endo-Surgery Inc.

Society of American Gastrointestinal and Endoscopic Surgeons 2008 Annual Scientific Session and Postgraduate Course. Presented April 12, 2008.

Surg Endosc. 2008;22:1112-1118.