Intraoperative Wound Irrigation for the Prevention of Surgical Site Infection After Laparotomy: A Randomized Clinical Trial by CHIR-Net.

Importance: Surgical site infections frequently occur after open abdominal surgery. Intraoperative wound irrigation as a preventive measure is a common practice worldwide, although evidence supporting this practice is lacking. Objective: To evaluate the preventive effect of intraoperative wound irrigation with polyhexanide solution. Design, Setting, and Participants: The Intraoperative Wound Irrigation to Prevent Surgical Site Infection After Laparotomy (IOWISI) trial was a multicenter, 3-armed, randomized clinical trial. Patients and outcome assessors were blinded to the intervention. The clinical trial was conducted in 12 university and general hospitals in Germany from September 2017 to December 2021 with 30-day follow-up. Adult patients undergoing laparotomy were eligible for inclusion. The main exclusion criteria were clean laparoscopic procedures and the inability to provide consent. Of 11 700 screened, 689 were included and 557 completed the trial; 689 were included in the intention-to-treat and safety analysis. Interventions: Randomization was performed online (3:3:1 allocation) to polyhexanide 0.04%, saline, or no irrigation (control) of the operative wound before closure. Main Outcome and Measures: The primary end point was surgical site infection within 30 postoperative days according to the US Centers for Disease Control and Prevention definition. Results: Among the 689 patients included, 402 were male and 287 were female. The median (range) age was 65.9 (18.5-94.9) years. Participants were randomized to either wound irrigation with polyhexanide (n = 292), saline (n = 295), or no irrigation (n = 102). The procedures were classified as clean contaminated in 92 cases (8%). The surgical site infection incidence was 11.8% overall (81 of 689), 10.6% in the polyhexanide arm (31 of 292), 12.5% in the saline arm (37 of 295), and 12.8% in the no irrigation arm (13 of 102). Irrigation with polyhexanide was not statistically superior to no irrigation or saline irrigation (hazard ratio [HR], 1.23; 95% CI, 0.64-2.36 vs HR, 1.19; 95% CI, 0.74-1.94; P = .47). The incidence of serious adverse events did not differ among the 3 groups. Conclusions and Relevance: In this study, intraoperative wound irrigation with polyhexanide solution did not reduce surgical site infection incidence in clean-contaminated open abdominal surgical procedures compared to saline or no irrigation. More clinical trials are warranted to evaluate the potential benefit in contaminated and septic procedures, including the emergency setting. Trial Registration: drks.de Identifier: DRKS00012251.

Effect of 2D vs. 3D laparoscopy on postoperative complications and operation time in a propensity-score-matched real-world data analysis.

BACKGROUND: Postoperative complication rates using 3D visualization are rarely reported. The primary aim of our study is to detect a possible advantage of using 3D on postoperative complication rates in a real-world setting. METHOD: With a sample size calculation for a medium effect size difference that 3D reduces significantly postoperative complications, data of 287 patients with 3D visualization and 832 with 2D procedure were screened. The groups underwent an exact propensity score-matching to be comparable. Comprehensive complication index (CCI) for every procedure was calculated and Operation Time was determined. RESULTS: Including 1078 patients in the study, 213 exact propensity score-matched pairs could finally be established. Concerning overall CCI (3D: 5.70 ± 13.63 vs. 2D: 3.37 ± 9.89; p = 0.076) and operation time (3D: 103.98 ± 93.26 min vs. 2D: 88.60 ±6 9.32 min; p = 0.2569) there was no significant difference between the groups. CONCLUSION: Our study shows no advantage of 3D over 2D laparoscopy regarding postoperative complications in a real-world setting, the second endpoint operation time, too, was not influenced by 3D overall.

Reducing Surgical Site Infection by Prophylactic Negative Pressure Wound Therapy in a Cohort of General Surgery Patients.

Background: Surgical site infection (SSI) is one of the leading complications in health care. Negative pressure wound therapy (NPWT) is meanwhile widely prophylactically used for preventing SSIs. For evaluating the results of the implantation of this technique, we used the Simon single-arm study design and examine whether NPWT has a prophylactic effect on reducing SSIs in a cohort of general surgery patients. Methods: This single-arm, two-stage study includes 81 elective general surgery patients and corresponds to the Simon's design. The sample size calculation was based on a reduction in the superficial SSI rate from 12 to 4% (power 80%, significance level 5%) using a NPWT system. In compliance with Simon's two-Stage design, the study required the recruitment of 34 patients in stage I and 47 patients in stage II. The two-stage design method would be discarded in case of a wound infection in 3 or more patients in stage I or 6 or more patients in stage II. Using the NPWT system in the operating room, a negative pressure wound dressing was applied post-operatively and removed after 7 days. According to the criteria of the Centres for Disease Control and Prevention (CDC), post-operative wound documentation followed on day 7 and 30. Results: In stage I, no SSI was apparent. In stage II, 3 patients had SSIs (CDC grade I). Conclusion: A prophylactic NPWT can significantly reduce the wound infection rate in elective general surgery.

Evaluating a Clinical Pathway in Laparoscopic Cholecystectomy: Effective in Reducing Complications? A Propensity Score Matching Analysis.

BACKGROUND: Care pathways are primarily aimed at decreasing length of hospital stay (LOS) and preventing unnecessary costs while maintaining or improving the quality of care. In laparoscopic cholecystectomy, there is insufficient evidence for proving an impact upon postoperative complications. METHODS: In this retrospective study, logistic regression was used to calculate a propensity score, and, after carrying out 1:1 nearest-neighbor matching, 296 patients were analyzed in both groups with regard to postoperative complications using the Clavien-Dindo classification system as a primary aim. In addition, secondary aims were LOS, compliance to care, and deviation from the care pathway with respect to patient discharge. Relative risk of the primary outcome was calculated and compared with the e-value as sensitivity testing approach. RESULTS: Due to the mandatory part of the care pathway, patient record compliance was 100%. Deviation from the care pathway with respect to the planned patient discharge on postoperative day 2 was noted in 16% of the cases. After adjustment for potential factors, the relative risk when comparing Clavien-Dindo complication grades 0 versus 1-4 is 1.64 (95% CI 0.87-3.11), which did not reach significance (p = 0.127). After matching, LOS lasted 3.69 days without and 3.26 days with the care pathway, respectively. CONCLUSIONS: Against the background of already implemented structured standard operation procedures, a care pathway is not able to reduce postoperative complications. Nevertheless, we consider our clinical pathway a highly valuable tool for the interdisciplinary management of patient hospitalization under the supervision of experienced specialized surgeons.

Graduated compression stockings in the prevention of postoperative pulmonary embolism. A propensity-matched retrospective case-control study of 24 273 patients.

INTRODUCTION: Recommendations for venous thromboembolism and deep venous thrombosis (DVT) prophylaxis using graduated compression stockings (GCS) is historically based and has been critically examined in current publications. Existing guidelines are inconclusive as to recommend the general use of GCS.Patients/Methods: 24 273 in-patients (general surgery and orthopedic patients) undergoing surgery between 2006 and 2016 were included in a retrospectively analysis from a single center. From January 2006 to January 2011 perioperative GCS was employed additionally to drug prophylaxis and from February 2011 to March 2016 patients received drug prophylaxis alone. According to german guidelines all patients received venous thromboembolism prophylaxis with weight-adapted LMWH. Risk stratification (low risk, moderate risk, high risk) was based on the guideline of the American College of Chest Physicians. Data analysis was performed before and after propensity matching (PM). The defined primary endpoint was the incidence of symptomatic or fatal pulmonary embolism (PE). A secondary endpoint was the incidence of deep venous thromboembolism (DVT). RESULTS: After risk stratification (low risk n = 16 483; moderate risk n = 4464; high risk n = 3326) a total of 24 273 patient were analyzed. Before to PM the relative risk for the occurrence of a PE or DVT was not increased by abstaining from GCS. After PM two groups of 11 312 patients each, one with and one without GCS application, were formed. When comparing the two groups, the relative risk (RR) for the occurrence of a pulmonary embolism was: Low Risk 0.99 [CI95% 0.998-1.000]; Moderate Risk 0.999 [CI95% 0.95-1.003]; High Risk 0.996 [CI95% 0.992-1.000] (p > 0.05). The incidence of PE in the total group LMWH alone was 0.1% (n = 16). In the total group using LMWH + GCS, the incidence was 0.3% (n = 29). RR after PM was 0.999 [CI95% 0.998-1.00]. CONCLUSION: In comparison to prior studies with only small numbers of patients our trial shows in a large group of patients with moderate and high risk developing VTE we can support the view that abstaining from GCS-use does not increase the incidence of symptomatic or fatal PE and symptomatic DVT.

Comparing large pore lightweight mesh versus small pore heavyweight mesh in open mesh plug repair of primary and recurrent unilateral inguinal hernia - A questionnaire study for a retrospective analysis of a cohort of elective groin hernia patients using propensity score matching.

PURPOSE: For surgical treatment of inguinal hernia, large-pore, lightweight mesh has been shown to offer advantages over small-pore, heavyweight options in terms of chronic post-operative inguinal pain, but without the disadvantage of having to deal with an increased recurrence rate. Limited data are available for the mesh plug repair technique. Therefore, the primary aim of this study is to compare large-pore, lightweight mesh versus small-pore, heavyweight mesh for mesh plug repair with regard to chronic pain and recurrences in elective primary unilateral hernias. In addition, we report our experience in repairing recurrent hernias. METHODS: Using a modified version of the questionnaire from the Danish Hernia Registry, two groups were surveyed: elective primary unilateral hernias and recurrent unilateral hernias. In both groups small-pore, heavyweight mesh (HWM) and lightweight, large-pore mesh (LWM) were compared with respect to chronic pain and recurrences. Propensity score matching (PS) was carried out on a pool of 1,782 patients. Effect sizes were assessed by using Cohen's d and Cramer's V. RESULTS: If the questionnaire item 'lump/swelling' is considered as a surrogate for recurrence (clinically verified in our study), the results in primary hernias after HWM show a 6.0% recurrence rate and 7.3% after LWM (p = 0.487) with a mean follow up of 31,3 months in HWM and 29,2 months in LWM respectively. The questionnaire item 'pain impacting on work/leisure activities' was answered with Yes in 11.5% following HWM and in 10.5% following LWM (p = 0.665). After the evaluation of the overall surgical results, we did not find differences. Comparing primary and recurrent hernia repair we found below small effect size differences with respect to the items of the questionnaire. CONCLUSIONS: The use of LWM in repairing elective unilateral primary hernias by the mesh plug technique does not result in less chronic pain and more recurrences when compared with HWM. Recurrent hernias repaired by the mesh plug technique may have same outcomes like in primary hernia repair when considering the magnitude of effect sizes.

Report of a Quality Improvement Program for Reducing Postoperative Complications by Using a Surgical Risk Calculator in a Cohort of General Surgery Patients.

PURPOSE: The study investigates whether postoperative complications in elective surgery can be reduced by using a risk calculator via raising the awareness of the surgeon in a preoperative briefing. Postoperative complications like wound infections or pneumonia result in a high burden for healthcare systems. Multiple quality improvement programs address this problem like the ACS NSQIP Surgical Risk Calculator® (SRC). METHODS: To determine whether the preoperative usage of the SRC could reduce inpatient postoperative complications, two groups of 832 patients each were compared using propensity score matching. The SRC was employed retrospectively in the period 2012/2013 in one group ("Retro") and prospectively in the other group ("Prosp") in the period 2014/2015. Actual inpatient postoperative complications were classified by SRC complication categories and compared with the Clavien-Dindo complication classification system (Dindo et al. in Ann Surg 240:205-213, 2004). RESULTS: Comparing SRC "serious complication" and SRC "any complication," a nonsignificant increase in the "Prosp"-group was apparent (serious complication: 6.6% vs. 8.5%, p = 0.164; any complication: 8.5% vs. 9.7%, p = 0.444). CONCLUSION: Use of the SRC neither reduces inpatient postoperative complications nor the severity of complications. The calculations of the SRC rely on a 30-day postoperative follow-up. Poor sensitivity and medium specificity of the SRC showed that the SRC could not make accurate predictions in a short follow-up time averaging 6 days. Alternatively, since the observed complication rate was low in our study, in an environment of already highly implemented risk management tools, reductions in complications are not easily achieved.

Correction to: ECMO-treatment in patients with acute lung failure, cardiogenic, and septic shock: mortality and ECMO-learning curve over a 6-year period.

[This corrects the article DOI: 10.1186/s40560-018-0352-2.].

Acute cholecystitis - a cohort study in a real-world clinical setting (REWO study, NCT02796443).

BACKGROUND: For decades, the optimal timing of surgery for acute cholecystitis has been controversial. Recent meta-analyses and population-based studies favor early surgery. One recent large randomized trial has demonstrated that a delayed approach increases morbidity and cost compared to early surgery within 24 hours of hospital admission. Since cases of severe cholecystitis were excluded from this trial, we argue that these results do not reflect real-world clinical situations. From our point of view, these results were in contrast to the clinical experience with our patients; so, we decided to analyze critically all our patients with the null hypothesis that the patients treated with a delayed cholecystectomy after an acute cholecystitis have a similar or even better outcome than those treated with an early operative approach. PATIENTS AND METHODS: We retrospectively analyzed clinical data from all patients with cholecystectomies in the period between January 2006 and September 2015. A total of 1,723 patients were categorized into four groups: early (n=138): urgent surgery of patients with acute cholecystitis within the first 72 hours of the onset of symptoms; intermediate (n=297): surgery of patients with acute cholecystitis within an average of 10 days after the onset of symptoms; delayed (n=427): initial non-surgical treatment of acute cholecystitis with surgery performed within 6-12 weeks of the onset of symptoms; and elective (n=868): cholecystectomy within a symptom-free interval of choice in patients with symptomatic cholecystolithiasis without signs of acute cholecystitis. RESULTS: In a real-world scenario, early/intermediate cholecystectomy in acute cholecystitis was associated with a significant increase in morbidity and mortality (Clavien-Dindo score) compared to a delayed approach with surgery performed 6-12 weeks after the onset of symptoms. The adjusted linear rank statistics showed a decrease in the complication score with values of 2.29 in the early group, 0.48 in the intermediate group, -0.26 in the delayed group and -2.12 in the elective group. The results translate into a continuous decrease of the complication score from early over intermediate and delayed to the elective group. CONCLUSION: These results demonstrate that delayed cholecystectomy can be performed safely. In cases with severe cholecystitis, early and/or intermediate approaches still have a relatively high risk of morbidity and mortality.

ECMO-treatment in patients with acute lung failure, cardiogenic, and septic shock: mortality and ECMO-learning curve over a 6-year period.

BACKGROUND: Based on promising results over the past 10 years, the method of extracorporeal membrane oxygenation (ECMO) has developed from being used as a 'rescue therapy' to become an accepted treatment option for patients with acute lung failure (ARDS). Subsequently, the indication was extended also to patients suffering from cardiogenic and septic shock. Our aim was to evaluate hospital mortality and associated prognostic variables in patients with lung failure, cardiogenic, and septic shock undergoing ECMO. Furthermore, a cumulative sum (CUSUM) analysis was used to assess the learning curve of ECMO-treatment in our department. METHODS: We retrospectively analysed the data of 131 patients undergoing ECMO treatment in the intensive care unit of the Asklepios Hospital of Langen over the time period from April 2011 to July 2016. We categorised the patients into three groups: lung failure (n = 54); cardiogenic shock (n = 58); and septic shock (n = 19). The primary outcome variable was hospital mortality along with identification of prognostic variables on mortality before initiating ECMO using logistic regression. Second outcome variable was the learning curve of our department in patients with ECMO. RESULTS: 6-year hospital mortality was 54% in patients with lung failure, 59% in patients with cardiogenic shock, and 58% in patients with septic shock.The CUSUM analysis revealed a typical learning curve with a point of inflection in the year 2014. Patients treated before 2014 had a worse outcome (p = 0.04 whole cohort; p = 0.03 for lung failure). Furthermore, less than 20 treatments per year respectively treatment before 2014 were associated negatively with hospital mortality of lung failure patients showing an odds ratio of 4.04, as well as in the entire cohort with an odds ratio of 3.19. CONCLUSION: For the first time, a steep ECMO-learning curve using the CUSUM tool has been described. Obviously, the experience with ECMO has to be taken into account when defining the role of ECMO in ARDS, cardiogenic, and septic shock.

2D vs. 3D imaging in laparoscopic surgery-results of a prospective randomized trial.

PURPOSE: 3D imaging is an upcoming technology in laparoscopic surgery, and recent studies have shown that the modern 3D technique is superior in an experimental setting. However, the first randomized controlled clinical trial in this context dates back to 1998 and showed no significant difference between 2D and 3D visualization using the first 3D generation technique, which is now more than 15 years old. METHODS: Positive results measured in an experimental setting considering 3D imaging on surgical performance led us to initiate a randomized controlled pragmatic clinical trial to validate our findings in daily clinical routine. Standard laparoscopic operations (cholecystectomy, appendectomy) were preoperatively randomized to a 2D or 3D imaging system. We used a surgical comfort scale (Likert scale) and the Raw NASA Workload TLX for the subjective assessment of 2D and 3D imaging; the duration of surgery was also measured. RESULTS: The results of 3D imaging were statistically significant better than 2D imaging concerning the parameters "own felt safety" and "task efficiency"; the difficulty level of the procedures in the 2D and 3D groups did not differ. Overall, the Raw NASA Workload TLX showed no significance between the groups. CONCLUSION: 3D imaging could be a possible advantage in laparoscopic surgery. The results of our clinical trial show increased personal felt safety and efficiency of the surgeon using a 3D imaging system. Overall of the procedures, the findings assessed using Likert scales in terms of own felt safety and task efficiency were statistically significant for 3D imaging. The individually perceived workload assessed with the Raw NASA TLX shows no difference. Although these findings are subjective impressions of the performing surgeons without a clear benefit for 3D technology in clinical outcome, we think that these results show the capability that 3D laparoscopy can have a positive impact while performing laparoscopic procedures.

Laparoscopic surgery: A qualified systematic review.

AIM: To review current applications of the laparoscopic surgery while highlighting the standard procedures across different fields. METHODS: A comprehensive search was undertaken using the PubMed Advanced Search Builder. A total of 321 articles were found in this search. The following criteria had to be met for the publication to be selected: Review article, randomized controlled trials, or meta-analyses discussing the subject of laparoscopic surgery. In addition, publications were hand-searched in the Cochrane database and the high-impact journals. A total of 82 of the findings were included according to matching the inclusion criteria. Overall, 403 full-text articles were reviewed. Of these, 218 were excluded due to not matching the inclusion criteria. RESULTS: A total of 185 relevant articles were identified matching the search criteria for an overview of the current literature on the laparoscopic surgery. Articles covered the period from the first laparoscopic application through its tremendous advancement over the last several years. Overall, the biggest advantage of the procedure has been minimizing trauma to the abdominal wall compared with open surgery. In the case of cholecystectomy, fundoplication, and adrenalectomy, the procedure has become the gold standard without being proven as a superior technique over the open surgery in randomized controlled trials. Faster recovery, reduced hospital stay, and a quicker return to normal activities are the most evident advantages of the laparoscopic surgery. Positive outcomes, efficiency, a lower rate of wound infections, and reduction in the perioperative morbidity of minimally invasive procedures have been shown in most indications. CONCLUSION: Improvements in surgical training and developments in instruments, imaging, and surgical techniques have greatly increased safety and feasibility of the laparoscopic surgical procedures.

Attributable mortality of ventilator-associated pneumonia: a meta-analysis of individual patient data from randomised prevention studies.

BACKGROUND: Estimating attributable mortality of ventilator-associated pneumonia has been hampered by confounding factors, small sample sizes, and the difficulty of doing relevant subgroup analyses. We estimated the attributable mortality using the individual original patient data of published randomised trials of ventilator-associated pneumonia prevention. METHODS: We identified relevant studies through systematic review. We analysed individual patient data in a one-stage meta-analytical approach (in which we defined attributable mortality as the ratio between the relative risk reductions [RRR] of mortality and ventilator-associated pneumonia) and in competing risk analyses. Predefined subgroups included surgical, trauma, and medical patients, and patients with different categories of severity of illness scores. FINDINGS: Individual patient data were available for 6284 patients from 24 trials. The overall attributable mortality was 13%, with higher mortality rates in surgical patients and patients with mid-range severity scores at admission (ie, acute physiology and chronic health evaluation score [APACHE] 20-29 and simplified acute physiology score [SAPS 2] 35-58). Attributable mortality was close to zero in trauma, medical patients, and patients with low or high severity of illness scores. Competing risk analyses could be done for 5162 patients from 19 studies, and the overall daily hazard for intensive care unit (ICU) mortality after ventilator-associated pneumonia was 1·13 (95% CI 0·98-1·31). The overall daily risk of discharge after ventilator-associated pneumonia was 0·74 (0·68-0·80), leading to an overall cumulative risk for dying in the ICU of 2·20 (1·91-2·54). Highest cumulative risks for dying from ventilator-associated pneumonia were noted for surgical patients (2·97, 95% CI 2·24-3·94) and patients with mid-range severity scores at admission (ie, cumulative risks of 2·49 [1·81-3·44] for patients with APACHE scores of 20-29 and 2·72 [1·95-3·78] for those with SAPS 2 scores of 35-58). INTERPRETATION: The overall attributable mortality of ventilator-associated pneumonia is 13%, with higher rates for surgical patients and patients with a mid-range severity score at admission. Attributable mortality is mainly caused by prolonged exposure to the risk of dying due to increased length of ICU stay. FUNDING: None.

Review of a large clinical series: Predicting death for patients with abdominal septic shock.

This paper reports the result of the MEDAN project that analyzes a multicenter septic shock patient data collection. The mortality prognosis based on 4 scores that are often used is compared with the prognosis of a trained neural network. We built an alarm system using the network classification results. Method. We analyzed the data of 382 patients with abdominal septic shock who were admitted to the intensive care unit (ICU) from 1998 to 2002. The analysis includes the calculation of daily sepsis-related organ failure assessment (SOFA), Acute Physiological and Chronic Health Evaluation (APACHE) II, simplified acute physiology score (SAPS) II, multiple-organ dysfunction score (MODS) scores for each patient and the training and testing of an appropriate neural network. Results. For our patients with abdominal septic shock, the analysis shows that it is not possible to predict their individual fate correctly on the day of admission to the ICU on the basis of any current score. However, when the trained network computes a score value below the threshold during the ICU stay, there is a high probability that the patient will die within 3 days. The trained neural network obtains the same outcome prediction performance as the best score, the SOFA score, using narrower confidence intervals and considering three variables only: systolic blood pressure, diastolic blood pressure and the number of thrombocytes. We conclude that the currently best available score for abdominal septic shock may be replaced by the output of a trained neural network with only 3 input variables.