Perioperative pain management with regional analgesia techniques for visceral cancer surgery: A systematic review and meta-analysis.

STUDY OBJECTIVE: Regional analgesia following visceral cancer surgery might provide an advantage but evidence for best treatment options related to risk-benefit is unclear. DESIGN: Systematic review of randomized controlled trials (RCT) with meta-analysis and GRADE assessment. SETTING: Postoperative pain treatment. PATIENTS: Adult patients undergoing visceral cancer surgery. INTERVENTIONS: Any kind of peripheral (PRA) or epidural analgesia (EA) with/without systemic analgesia (SA) was compared to SA with or without placebo treatment or any other regional anaesthetic techniques. MEASUREMENTS: Primary outcome measures were postoperative acute pain intensity at rest and during activity 24 h after surgery, the number of patients with block-related adverse events and postoperative paralytic ileus. MAIN RESULTS: 59 RCTs (4345 participants) were included. EA may reduce pain intensity at rest (mean difference (MD) -1.05; 95% confidence interval (CI): -1.35 to -0.75, low certainty evidence) and during activity 24 h after surgery (MD -1.83; 95% CI: -2.34 to -1.33, very low certainty evidence). PRA likely results in little difference in pain intensity at rest (MD -0.75; 95% CI: -1.20 to -0.31, moderate certainty evidence) and pain during activity (MD -0.93; 95% CI: -1.34 to -0.53, moderate certainty evidence) 24 h after surgery compared to SA. There may be no difference in block-related adverse events (very low certainty evidence) and development of paralytic ileus (very low certainty of evidence) between EA, respectively PRA and SA. CONCLUSIONS: Following visceral cancer surgery EA may reduce pain intensity. In contrast, PRA had only limited effects on pain intensity at rest and during activity. However, we are uncertain regarding the effect of both techniques on block-related adverse events and paralytic ileus. Further research is required focusing on regional analgesia techniques especially following laparoscopic visceral cancer surgery.

Adherence to fast track measures in colorectal surgery-a survey among German and Austrian surgeons.

PURPOSE: The effectiveness of modern perioperative treatment concepts has been demonstrated in several studies and meta-analyses. Despite good evidence, limited implementation of the fast track (FT) concept is still a widespread concern. To assess the status quo in Austrian and German hospitals, a survey on the implementation of FT measures was conducted among members of the German Society of General and Visceralsurgery (DGAV), the German Society of Coloproctology (DGK) and the Austrian Society of Surgery (OEGCH) to analyze where there is potential for improvement. METHODS: Twenty questions on perioperative care of colorectal surgery patients were sent to the members of the DGAV, DGK and OEGCH using the online survey tool SurveyMonkey®. Descriptive data analysis was performed using Microsoft Excel. RESULTS: While some of the FT measures have already been routinely adopted in clinical practice (e.g. minimally invasive surgical approach, early mobilization and diet buildup), for other components there are discrepancies between current recommendations and present implementation (e.g. the use of local nerve blocks to provide opioid-sparing analgesia or the use of abdominal drains). CONCLUSION: The implementation of the FT concept in Austria and Germany is still in need of improvement. Particularly regarding the use of abdominal drains and postoperative analgesia, there is a tendency to stick to traditional structures. To overcome the issues with FT implementation, the development of an evidence-based S3 guideline for perioperative care, followed by the founding of a surgical working group to conduct a structured education and certification process, may lead to significant improvements in perioperative patient care.

Preoperative combined mechanical and oral antibiotic bowel preparation for preventing complications in elective colorectal surgery.

BACKGROUND: The success of elective colorectal surgery is mainly influenced by the surgical procedure and postoperative complications. The most serious complications include anastomotic leakages and surgical site infections (SSI)s, which can lead to prolonged recovery with impaired long-term health.  Compared with other abdominal procedures, colorectal resections have an increased risk of adverse events due to the physiological bacterial colonisation of the large bowel. Preoperative bowel preparation is used to remove faeces from the bowel lumen and reduce bacterial colonisation. This bowel preparation can be performed mechanically and/or with oral antibiotics. While mechanical bowel preparation alone is not beneficial, the benefits and harms of combined mechanical and oral antibiotic bowel preparation is still unclear. OBJECTIVES: To assess the evidence for the use of combined mechanical and oral antibiotic bowel preparation for preventing complications in elective colorectal surgery. SEARCH METHODS: We searched MEDLINE, Embase, CENTRAL and trial registries on 15 December 2021. In addition, we searched reference lists and contacted colorectal surgery organisations. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of adult participants undergoing elective colorectal surgery comparing combined mechanical and oral antibiotic bowel preparation (MBP+oAB) with either MBP alone, oAB alone, or no bowel preparation (nBP). We excluded studies in which no perioperative intravenous antibiotic prophylaxis was given. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures as recommended by Cochrane. Pooled results were reported as mean difference (MD) or risk ratio (RR) and 95 % confidence intervals (CIs) using the Mantel-Haenszel method. The certainty of the evidence was assessed with GRADE. MAIN RESULTS: We included 21 RCTs analysing 5264 participants who underwent elective colorectal surgery. None of the included studies had a high risk of bias, but two-thirds of the included studies raised some concerns. This was mainly due to the lack of a predefined analysis plan or missing information about the randomisation process. Most included studies investigated both colon and rectal resections due to malignant and benign surgical indications. For MBP as well as oAB, the included studies used different regimens in terms of agent(s), dosage and timing.  Data for all predefined outcomes could be extracted from the included studies. However, only four studies reported on side effects of bowel preparation, and none recorded the occurrence of adverse effects such as dehydration, electrolyte imbalances or the need to discontinue the intervention due to side effects. Seventeen trials compared MBP+oAB with sole MBP. The incidence of SSI could be reduced through MBP+oAB by 44% (RR 0.56, 95% CI 0.42 to 0.74; 3917 participants from 16 studies; moderate-certainty evidence) and the risk of anastomotic leakage could be reduced by 40% (RR 0.60, 95% CI 0.36 to 0.99; 2356 participants from 10 studies; moderate-certainty evidence). No difference between the two comparison groups was found with regard to mortality (RR 0.87, 95% CI 0.27 to 2.82; 639 participants from 3 studies; moderate-certainty evidence), the incidence of postoperative ileus (RR 0.89, 95% CI 0.59 to 1.32; 2013 participants from 6 studies, low-certainty of evidence) and length of hospital stay (MD -0.19, 95% CI -1.81 to 1.44; 621 participants from 3 studies; moderate-certainty evidence). Three trials compared MBP+oAB with sole oAB. No difference was demonstrated between the two treatment alternatives in terms of SSI (RR 0.87, 95% CI 0.34 to 2.21; 960 participants from 3 studies; very low-certainty evidence), anastomotic leakage (RR 0.84, 95% CI 0.21 to 3.45; 960 participants from 3 studies; low-certainty evidence), mortality (RR 1.02, 95% CI 0.30 to 3.50; 709 participants from 2 studies; low-certainty evidence), incidence of postoperative ileus (RR 1.25, 95% CI 0.68 to 2.33; 709 participants from 2 studies; low-certainty evidence) or length of hospital stay (MD 0.1 respectively 0.2, 95% CI -0.68 to 1.08; data from 2 studies; moderate-certainty evidence). One trial (396 participants) compared MBP+oAB versus nBP. The evidence is uncertain about the effect of MBP+oAB on the incidence of SSI as well as mortality (RR 0.63, 95% CI 0.33 to 1.23 respectively RR 0.20, 95% CI 0.01 to 4.22; low-certainty evidence), while no effect on the risk of anastomotic leakages (RR 0.89, 95% CI 0.33 to 2.42; low-certainty evidence), the incidence of postoperative ileus (RR 1.18, 95% CI 0.77 to 1.81; low-certainty evidence) or the length of hospital stay (MD 0.1, 95% CI -0.8 to 1; low-certainty evidence) could be demonstrated. AUTHORS' CONCLUSIONS: Based on moderate-certainty evidence, our results suggest that MBP+oAB is probably more effective than MBP alone in preventing postoperative complications. In particular, with respect to our primary outcomes, SSI and anastomotic leakage, a lower incidence was demonstrated using MBP+oAB. Whether oAB alone is actually equivalent to MBP+oAB, or leads to a reduction or increase in the risk of postoperative complications, cannot be clarified in light of the low- to very low-certainty evidence. Similarly, it remains unclear whether omitting preoperative bowel preparation leads to an increase in the risk of postoperative complications due to limited evidence. Additional RCTs, particularly on the comparisons of MBP+oAB versus oAB alone or nBP, are needed to assess the impact of oAB alone or nBP compared with MBP+oAB on postoperative complications and to improve confidence in the estimated effect. In addition, RCTs focusing on subgroups (e.g. in relation to type and location of colon resections) or reporting side effects of the intervention are needed to determine the most effective approach of preoperative bowel preparation.

[Robot-assisted rectal resections-Scoping review for level 1a evidence and retrospective analysis of in-clinic data]. / Robotergestützte Rektumresektionen ­ Scoping-Review für Klasse-1a-Evidenz und retrospektive Analyse klinikinterner Daten.

BACKGROUND: Robot-assisted rectal resections are said to overcome the known difficulties of laparoscopic rectal surgery through technical advantages, leading to better treatment results; however, published studies reported very heterogeneous results. The aim of this paper is therefore to determine whether there is class 1a evidence comparing robotic versus laparoscopic rectal resections. Furthermore, we would like to compare the treatment results of our clinic with the calculated effects from the literature. MATERIAL AND METHODS: A systematic literature search for class 1a evidence was performed and the calculated effects for 7 preselected outcomes were compared. We then analyzed all elective rectal resections performed in our hospital between 2017 and 2020 and compared the treatment outcomes with the results of the identified meta-analyses. RESULTS: The results of the 7 identified meta-analyses did not show homogeneous effects for the outcomes operating time and conversion rate, while the calculated effects of the other outcomes studied were largely consistent. Our patient data showed that robotic rectal resections were associated with significantly longer operation times, while the other outcomes were hardly influenced by the surgical technique. DISCUSSION: Although class 1a meta-analyses comparing robotic and laparoscopic rectal resections already exist, they do not enable an evidence-based recommendation regarding the preference of one of the two surgical techniques. The analysis of our patient data showed that the results achieved in our clinic are largely consistent with the observed effects of the meta-analyses.

Predictors of Morbidity and Mortality After Colorectal Surgery in Patients With Cirrhotic Liver Disease-A Retrospective Analysis of 54 Cases at a Tertiary Care Center.

Background: Despite various existing scores that predict morbidity and mortality of patients with cirrhotic liver disease (CLD), data on specific risk stratification of patients with CLD undergoing colorectal surgery (CRS) are rare. The aim of this study was to assess in-hospital morbidity and mortality of patients with liver cirrhosis scheduled for CRS, with specific focus on possible pitfalls of surgery in this special cohort. Methods: Between 1996 and 2018, 54 patients with CLD undergoing CRS were identified and included in this study cohort. Postoperative morbidity and mortality were assessed using the Clavien/Dindo (C/D) classification as well as by type of complication. Univariate and multivariate analyses were performed to analyze the predictive factors for increased postoperative morbidity. Results: Of the patients, 37% patients died during the procedure or postoperatively. Major complications were seen in 23.1% of patients (>C/D IIIb). Patients with Child B or C cirrhosis as well as patients undergoing emergency surgery experienced significantly more major complications (p = 0.04 and p = 0.023, respectively). The most common complications were bleeding requiring blood transfusion (51.1%) and cardiocirculatory instability due to bleeding or sepsis (44.4%). In 53.7% of patients, an anastomosis was created without a protective ostomy. Anastomotic leakage occurred in 20.7% of these patients. Multivariate analysis showed that a primary anastomosis without a protective ostomy was the strongest risk factor for major complications (p = 0.042). Discussion: Morbidity and mortality after CRS in patients with CLD remains high and is not only influenced by liver function but also by surgical variables. Considering the high rate of anastomotic leakage, creating a protective or definitive ostomy must be considered with regard to the underlying pathology, the extent of CLD, and the patient's condition. Moreover, our data suggest that surgery in these most fragile patients should be performed only in experienced centers with immediate contact to hepatologists and experts in hemostasis.

Surgical treatment of mechanical bowel obstruction: characteristics and outcomes of geriatric patients compared to a younger cohort.

PURPOSE: Mechanical bowel obstruction (MBO) is one of the most common indications for emergency surgery. Recent research justifies the method of attempting 3-5 days of nonoperative treatment before surgery. However, little is known about specific characteristics of geriatric patients undergoing surgery compared to a younger cohort. We aimed to analyze patients with MBO that required surgery, depending on their age, to identify potential targets for use in the reduction in complications and mortality in the elderly. METHODS: Thirty-day and in-hospital mortality were determined as primary outcome. We retrospectively identified all patients who underwent surgery for MBO at the University Hospital of Bonn between 2009 and 2019 and divided them into non-geriatric (40-74 years, n = 224) and geriatric (≥ 75 years, n = 88) patients, using the chi-squared-test and Mann-Whitney U test for statistical analysis. RESULTS: We found that geriatric patients had higher 30-day and in-hospital mortality rates than non-geriatric patients. As secondary outcome, we found that they experienced a longer length of stay (LOS) and higher complication rates than non-geriatric patients. Geriatric patients who suffered from large bowel obstruction (LBO) had a higher rate of bowel resection, stoma creation, and a higher 30-day mortality rate. The time from admission to surgery was not shown to be crucial for the outcome of (geriatric) patients. CONCLUSION: Geriatric patients suffering from mechanical bowel obstruction that had to undergo surgery had higher mortality and morbidity than non-geriatric patients. Especially in regard to geriatric patients, clinicians should treat patients in a risk-adapted rather than time-adapted manner, and conditions should be optimized before surgery.

Transcutaneous vagal nerve simulation to reduce a systemic inflammatory response syndrome and the associated intestinal failure: study protocol of a prospective, two-armed, sham-controlled, double-blinded trial in healthy subjects (the NeuroSIRS-Study).

PURPOSE: Surgery initiates pro-inflammatory mediator cascades leading to a variably pronounced sterile inflammation (SIRS). SIRS is associated with intestinal paralysis and breakdown of intestinal barrier and might result in abdominal sepsis. Technological progress led to the development of a neurostimulator for transcutaneous auricular vagal nerve stimulation (taVNS), which is associated with a decline in inflammatory parameters and peristalsis improvement in rodents and healthy subjects via activation of the cholinergic anti-inflammatory pathway. Therefore, taVNS might be a strategy for SIRS prophylaxis. METHODS: The NeuroSIRS-Study is a prospective, randomized two-armed, sham-controlled, double-blind clinical trial. The study is registered at DRKS00016892 (09.07.2020). A controlled endotoxemia is used as a SIRS-mimicking model. 2 ng/kg bodyweight lipopolysaccharide (LPS) will be administered after taVNS or sham stimulation. The primary objective is a reduction of clinical symptoms of SIRS after taVNS compared to sham stimulation. Effects of taVNS on release of inflammatory cytokines, intestinal function, and vital parameters will be analyzed. DISCUSSION: TaVNS is well-tolerated, with little to no side effects. Despite not fully mimicking postoperative inflammation, LPS challenge is the most used experimental tool to imitate SIRS and offers standardization and reproducibility. The restriction to healthy male volunteers exerts a certain bias limiting generalizability to the surgical population. Still, this pilot study aims to give first insights into taVNS as a prophylactic treatment in postoperative inflammation to pave the way for further clinical trials in patients at risk for SIRS. This would have major implications for future therapeutic approaches.

Electrical vagus nerve stimulation as a prophylaxis for SIRS and postoperative ileus.

Abdominal surgery results in an activation of immune cells of the bowel wall and a consecutive cytokine and nitric oxide (NO) release leading to an inflammation of the muscularis externa and a bowel paralysis, the so-called postoperative ileus (POI). In addition to the local inflammation, major surgical trauma can also lead to a variable pronounced systemic inflammation up to its maximum variant, the systemic inflammatory response syndrome (SIRS), with hypotension, capillary leak and a breakdown of the intestinal barrier function followed by multi-organ dysfunction (MODS). Until now, neither for SIRS nor for POI, a prophylaxis or an evidence-based treatment exists. Since the pioneering work from Kevin Tracey and his group in the late 90s characterizing the role of the vagus nerve in inflammation and describing the cholinergic anti-inflammatory pathway (CAIP) for the first time, substantial efforts have been made in the research field of neuro-immune interactions. Today, the anti-inflammatory potential of vagus nerve stimulation is moving more and more into focus resulting in new therapeutic approaches. This review focuses on the role of the CAIP in the development of SIRS and POI. Furthermore, new therapeutic options like transcutaneous vagus nerve stimulation are highlighted.

[Background, Necessity and Methodology of the S3 Guideline "Perioperative Management of Gastrointestinal Tumours (POMGAT)"]. / Hintergrund, Notwendigkeit und Methodik der S3-Leitlinie "Perioperatives Management bei gastrointestinalen Tumoren (POMGAT)".

Malignancies are among the most common diseases, especially in old age, and are responsible for 25% of all deaths in Germany. Especially carcinomas of the gastrointestinal tract can be cured in most cases only through extensive surgery with significant morbidity. About 25 years ago, the multimodal, perioperative Fast Track (FT) concept for reducing postoperative complications was introduced and additional elements were added in the following years. Meanwhile, there is growing evidence that adherence to the key elements of more than 70% leads to reduction in postoperative adverse events as well as a shorter hospital stay and could be associated with an improved oncological outcome. Despite the high level of awareness and the proven advantages of the FT concept, the implementation and maintenance of the measures is difficult and results in an adherence of only 20 - 40%. There are many reasons for this: In addition to a lack of interdisciplinary and interprofessional cooperation and the time consuming and extended logistical efforts, limited human resources are often listed as one of the main causes. We took these aspects as an opportunity and started to develop a S3 guideline for perioperative treatment to accelerate the recovery of patients with gastrointestinal malignancies. By creating a consensus- and evidence-based, multidisciplinary guideline, many of the problems listed above could probably be solved by optimising and standardising interdisciplinary care, which is particularly important in a setting with many different disciplines and their competing interests. Furthermore, the standardisation of the perioperative procedures will reduce the time and logistical effort. The presentation of the evidence allows increased transparency and justifies the additional personnel expenditure on hospital medicine and health insurance companies. In addition, the evidence-based quality indicators generated during the development of the guideline make it possible to include perioperative standards in certification systems and thus to measure and check the quality of perioperative care.

[Evaluation of the Effectiveness of a Standard Operating Procedure (SOP) for the Perioperative Management of Colorectal Surgery]. / Evaluation der Effektivität einer Standard Operating Procedure (SOP) zur perioperativen Therapie bei kolorektalen Operationen.

INTRODUCTION: In recent years, perioperative care of patients after colorectal surgery has been increasingly standardised according to the fast-track concept and is accepted as a structured method of care to reduce perioperative complications. Indeed, initial studies have indicated that there is a long-term favourable effect on the oncological outcome, if the adherence to the individual measures is at least 70%. Even though there is unambiguous evidence for the efficacy of the modern perioperative treatment concept, it is often difficult to comply with the protocol during normal clinical work, particularly in Germany. The objective of this study was to record the rate of compliance before and after the introduction of the SOP and to evaluate its efficacy. METHODS: We performed a retrospective analysis of the patient data after all elective colorectal surgery in the Bonn University Hospital from 2017 to 2020. 153 patients were operated on before the implementation of the SOP in January 2019 (group I); the remaining 153 patients were operated on after the implementation of the SOP and received appropriate care (group II). Compliance to the protocol was analysed for both the individual key interventions and the overall concept. RESULTS: There was significant improvement in the compliance for both the individual measures (prehabilitation group I: 5.9%, group II: 42.5%, p < 0.001; preparation of the intestine I: 16.5%, II: 73.9%, p < 0.001; intraoperative volume management I: 14,00 ml/kg BW/h, II: 9.12 ml/kg BW/h, p < 0.001, BW: body weight; minimally invasive surgical technique I: 53.6%, II: 73.9%, p < 0.001; etc.) and for the overall perioperative treatment concept (I: 39%, II: 54%, p = 0.02). However, we fell far short of compliance of at least 70%. Nevertheless, patient autonomy was achieved earlier after introduction of the SOP (I: day 15, II: day 9, p < 0.001) and the postoperative hospital stay was shortened (I: 14 [6 - 99] days, II 11 [4 - 64] days; p = 0.007). CONCLUSION: Although the implementation of the SOP led to significant improvements, further optimisation is required to attain the recommended protocol compliance of 70%. Measures within the hospital could include foundation of an interdisciplinary fast-track team and a specialised nurse as the connecting link between the patients, nursing and physicians. On the other hand, implementation throughout Germany can only be achieved by more influential actions. One possible support would be the S3 guideline on perioperative management of gastrointestinal tumours, which is under development. This could, for example, be used to support argumentation with funding providers.

Risk Factors for Postoperative Morbidity and Mortality after Small Bowel Surgery in Patients with Cirrhotic Liver Disease-A Retrospective Analysis of 76 Cases in a Tertiary Center.

(1) Purpose: As it is known, patients with liver cirrhosis (LC) undergoing colon surgery or hernia surgery have high perioperative morbidity and mortality. However, data about patients with LC undergoing small bowel surgery is lacking. This study aimed to analyze the morbidity and mortality of patients with LC after small bowel surgery in order to determine predictive risk factors for a poor outcome. (2) Methods: A retrospective analysis was performed of all patients undergoing small bowel surgery between January 2002 and July 2018 and identified 76 patients with LC. Postoperative complications were analyzed using the classification of Dindo/Clavien (D/C) and further subdivided (hemorrhage, pulmonary complication, wound healing disturbances, renal failure). A total of 38 possible predictive factors underwent univariate and multivariate analyses for different postoperative complications and in-hospital mortality. (3) Results: Postoperative complications [D/C grade ≥ II] occurred in 90.8% of patients and severe complications (D/C grade ≥ IIIB) in 53.9% of patients. Nine patients (11.8%) died during the postoperative course. Predictive factors for overall complications were "additional surgery" (OR 5.3) and "bowel anastomosis" (OR 5.6). For postoperative mortality, we identified the model of end-stage liver disease (MELD) score (OR 1.3) and portal hypertension (OR 5.8) as predictors. The most common complication was hemorrhage, followed by pulmonary complications, hydropic decompensation, renal failure, and wound healing disturbances. The most common risk factors for those complications were portal hypertension (PH), poor liver function, emergency or additional surgery, ascites, and high ASA score. (4) Conclusions: LC has a devastating influence on patients' outcomes after small bowel resection. PH, poor liver function, high ASA score, and additional or emergency surgery as well as ascites were significant risk factors for worse outcomes. Therefore, PH should be treated before surgery whenever possible. Expansion of the operation should be avoided whenever possible and in case of at least moderate preoperative ascites, the creation of an anastomotic ostomy should be evaluated to prevent leakages.