European Surgical Research最新文献

Introduction: Anastomotic leaks (ALs) are serious postoperative complications. Current experimental studies designed to investigate leaks are based on acute intraoperative dehiscence of the anastomosis. Clinically, however, AL usually happens later in the postoperative course. Presented here is a clinically relevant colonic AL model in swine.

Methods: Seventeen Yorkshire pigs were divided into 2 groups: the control group (n = 6) and the experimental group (n = 11). An enterotomy was performed on the descending colon and an end-to-end handsewn anastomosis was created in the groups. The proximal and distal ends of the suture were exteriorized and tied to a plastic tube. Subsequently, the suture was cut and pulled to induce breakdown of the anastomosis in the experimental group 3-4 h postoperatively. Study endpoints included behavioral changes, clinical assessment, laboratory indicators, and macroscopic indicators of leakage.

Results: Leaks were successfully created in 8/11 of the experimental group animals and confirmed through exploratory relaparotomy. Seven of the experimental pigs showed complete anastomotic breakdown and one showed partial rupture. Fecal peritonitis and enteric spillage were observed macroscopically within the abdomen of the experimental pigs, confirming the presence of a leak. The remaining (3/11) experimental pigs did not experience those findings due to either a tamponade/containment by the abdominal wall or surrounding organs. Statistical significance (p < 0.05) was achieved between the experimental and control cohorts for laboratory and clinical indicators including fever, leukocytosis, and decreased blood potassium.

Conclusion: This animal model generated postoperative induced leak in approximately three-quarters (8/11) of experimental pigs, allowing control over the time of leak onset to simulate clinical settings.

Introduction: Post-hepatectomy liver failure (PHLF) is a serious complication associated with major hepatectomies. An accurate prediction of PHLF is necessary to determine the feasibility of major hepatectomy. This study aimed to assess the association between PHLF and preoperative laboratory and computed tomography (CT) findings.

Methods: Medical records of 65 patients who underwent major hepatectomy and preoperative CT were retrospectively reviewed. We evaluated future remnant liver volume evaluation models and remnant liver hemodynamics, which were assessed by arterial enhancement fraction (AEF) by using preoperative CT. Variables, including CT findings, were compared between patients with and without PHLF after major hepatectomy, and the preoperative PHLF-predicting nomogram was constructed using multivariate logistic regression.

Results: The PHLF group included 21 patients (32.3%). The AEF was not significantly different between the two groups. In the future remnant liver volume evaluation models, future remnant liver proportion (fRLP) had the highest concordance index (C-index) in the receiver operating characteristic curve analysis (C-index, 0.755). Multivariate analysis of preoperative evaluable factors revealed that alanine aminotransferase levels (p = 0.034), prothrombin time activity (p = 0.021), and fRLP (p = 0.012) were independent predictive factors of PHLF. A nomogram (APART score) was constructed using these three factors, with a receiver operating curve showing a C-index of 0.894. According to the APART score, scores of 51-60 indicated moderate risk (40.0%), and scores over 60 indicated a high risk of PHLF (83.3%) (p < 0.001).

Discussion: The APART score may help predict PHLF in patients indicated for major hepatectomies.

In kidney transplantation (KTx), renal graft thrombosis (RGT) is one of the main reasons for early graft loss. Although evidence-based guidance on prevention of RGT is lacking, thromboprophylaxis is widely used. The aim of this survey was to obtain a European view of the different thromboprophylactic strategies applied in KTx. An online 22-question survey, addressed to KTx professionals, was distributed by email and via platforms of the European Society for Organ Transplantation. Seventy-five responses (21 countries, 51 centers) were received: 75% had over 10 years' clinical experience, 64% were surgeons, 29% nephrologists, and 4% urologists. A written antithrombotic management protocol was available in 75% of centers. In 8 (16%) centers, respondents contradicted each other regarding the availability of a written protocol. Thromboprophylaxis is preferred by 78% of respondents, independent of existing antithrombotic management protocols. Ninety-two percent of respondents indicated that an anticipated bleeding risk is the main reason to discontinue chronic antithrombotic therapy preoperatively. Intraoperatively, 32% of respondents administer unfractionated heparin (400-10,000 international units with a median of 5,000) in selected cases. Despite an overall preference for perioperative thromboprophylaxis in KTx, there is a high variation within Europe regarding type, timing, and dosage, most likely due to the paucity of high-quality studies. Further research is warranted in order to develop better guidelines.

Introduction: Hemorrhage is a challenging complication of pelvic surgery. This study aimed to analyze the causes, management, and factors associated with morbidity in patients experiencing major pelvic hemorrhage during complex abdominopelvic surgery.

Methods: Patients who had major intraoperative pelvic hemorrhage during complex abdominopelvic surgery at 11 tertiary referral centers between 1997 and 2017 were included. Patient characteristics, management strategies to control bleeding, short- and long-term postoperative outcomes were evaluated retrospectively.

Results: There were 120 patients with a mean age of 56.6 ± 2.4 years and a mean BMI of 28.3 ± 1 kg/m2. While 104 (95%) of the patients were operated for malignancy, 16 (5%) of the patients had surgery for a benign disease. The most common bleeding site was the presacral venous plexus 90 (75%). Major pelvic hemorrhage was managed simultaneously in 114 (95%) patients. Electrocauterization 27 (23%), pelvic packing 26 (22%), suturing 7 (6%), thumbtacks application 7 (6%), muscle welding 4 (4%), use of energy devices 2 (2%), and topical hemostatic agents 2 (2%) were the management tools. Combined techniques were used in 43 (36%) patients. Short-term morbidity and mortality rates were 48 (40%) and 2 (2%), respectively. High preoperative CRP levels (p = 0.04), history of preoperative radiotherapy (p = 0.04), longer bleeding time (p = 0.006), and increased blood transfusion (p = 0.005) were the factors associated with postoperative morbidity.

Conclusion: Postoperative morbidity related to major pelvic hemorrhage can be reduced by optimizing the risk factors. Prehabilitation prior to surgery to moderate inflammatory status and prompt action with proper technique to control major pelvic hemorrhage can prevent excessive blood loss in complex abdominopelvic surgery.

Background: Wound healing of the skin is a very complex biological activity. For a better understanding, an attempt is made to describe and subdivide the different players (cell types and signaling molecules), patterns (different regeneration or repair mechanisms), and processes (division of the overall process into categories, phases, and steps). However, this is always based on different points of view. On the one hand, the temporality of the phases and on the other hand, the dominant activity in each step can play a role. In addition, classifications according to wound theory and wound treatment are possible.

Summary: To gain an initial overview of (human) skin wound healing, simple classifications are advantageous for understanding and thus deserve to exist. The complexity of the underlying biology of skin wound healing takes on a multidimensional configuration upon closer examination, in which new actors are constantly being identified, making the events more precise and comprehensible but also significantly confusing when viewed as a whole. From this point of view, the healing process must be categorized so that the observer does not get lost in the multitude of interacting processes. In view of the steadily increasing knowledge, which includes in parallel the physiological as well as the pathophysiological processes of wound healing, the classification according to function in the sense of consecutive and overlapping phases seems the most convenient and considers the corresponding processes more precisely. Despite that many mechanisms and specific cellular functions in wound healing have been identified, many underlying (patho-)physiological processes still remain unknown.

Key messages: Currently, a substantial part of research activities in medicine is limited to molecular levels, while evidence for therapies currently in use is lacking or newly gained knowledge is quite far from clinical applicability and reality. This article aimed to shed more light on the various classifications of skin wound healing and presents the underlying paradigms starting from simple approaches and ending with more detailed concepts.

Introduction: Sheep are frequently used in translational surgical orthopedic studies. Naturally, a good pain management is mandatory for animal welfare, although it is also important with regard to data quality. However, methods for adequate severity assessment, especially considering pain, are rather rare regarding large animal models. Therefore, in the present study, accompanying a surgical pilot study, telemetry and the Sheep Grimace Scale (SGS) were used in addition to clinical scoring for severity assessment after surgical interventions in sheep.

Methods: Telemetric devices were implanted in a first surgery subcutaneously into four German black-headed mutton ewes (4-5 years, 77-115 kg). After 3-4 weeks of recovery, sheep underwent tendon ablation of the left M. infraspinatus. Clinical scoring and video recordings for SGS analysis were performed after both surgeries, and the heart rate (HR) and general activity were monitored by telemetry.

Results: Immediately after surgery, clinical score and HR were slightly increased, and activity was decreased in individual sheep after both surgeries. The SGS mildly elevated directly after transmitter implantation but increased to higher levels after tendon ablation immediately after surgery and on the following day.

Conclusion: In summary, SGS- and telemetry-derived data were suitable to detect postoperative pain in sheep with the potential to improve individual pain recognition and postoperative management, which consequently contributes to refinement.

Background: Tympanic membrane perforations (TMPs) are a common complication of trauma and infection. Persisting perforations result from the unique location of the tympanic membrane. The wound is surrounded by air of the middle ear and the external auditory canal. The inadequate wound bed, growth factor, and blood supply lead to circular epithelialization of the perforation's edge and premature interruption of defect closure. Orthotopic animal models use mechanical or chemical tympanic membrane laceration to identify bioactive wound dressings and overcome premature epithelialization. However, all orthotopic models essentially lack repetitive visualization of the biomaterial-wound interface. Therefore, recent progress in 3D printing of customized wound dressings has not yet been transferred to the unique wound setup of the TMP. Here, we present a novel application for the mice dorsal skinfold chamber (DSC) with an epithelialized full-thickness defect as TMP model.

Methods: A circular 2-mm defect was cut into the extended dorsal skinfold using a biopsy punch. The skinfold was either perforated through both skin layers without prior preparation or perforated on 1 side, following resection of the opposing skin layer. In both groups, the wound was sealed with a coverslip or left unclosed (n = 4). All animals were examined for epithelialization of the edge (histology), size of the perforation (planimetry), neovascularization (repetitive intravital fluorescence microscopy), and inflammation (immunohistology).

Results: The edge of the perforation was overgrown by the cornified squamous epithelium in all pre-parations. Reduction in the perforation's size was enhanced by application of a coverslip. Microsurgical preparation before biopsy punch perforation and sealing with a coverslip enabled repetitive high-quality intravital fluorescence microscopy. However, spontaneous reduction of the perforation occurred frequently. Therefore, the direct biopsy punch perforation without microsurgical preparation was favorable: spontaneous reduction did not occur throughout 21 days. Moreover, the visualization of the neovascularization was sufficient in intravital microscopy.

Conclusions: The DSC full-thickness defect is a valuable supplement to orthotopic TMP models. Repetitive intravital microscopy of the epithelialized edge enables investigation of the underlying pathophysiology during the transition from the inflammation to the proliferation phase of wound healing. Using established analysis procedures, the present model provides an effective platform for the screening of bioactive materials and transferring progress in tissue engineering to the special conditions of tympanic membrane wound healing.

Introduction: We investigated the effect of the gastrojejunostomy position on the postoperative oral intake in patients who have undergone pancreaticoduodenectomy (PD).

Methods: We investigated 119 patients who underwent PD between June 2013 and December 2019 and examined the effect of the horizontal and vertical distance rates of the gastrojejunostomy position on the postoperative oral intake. The patients were categorized as having poor or good oral intake based on whether their intake was up to half the required calorie intake.

Results: There were significant differences in the number of cases with grade B or C postoperative pancreatic fistula (good, 20.3% vs. poor, 60.0%; p < 0.001), horizontal distance rate (good, 0.57 vs. poor, 0.48; p = 0.02), and postoperative hospitalization period (good, 15 vs. poor, 35 days; p < 0.001). However, there was no significant difference in the vertical distance rate (good, 0.67 vs. poor, 0.71; p = 0.22). The horizontal distance rate was the independent risk factor for postoperative poor oral intake at 2-3 weeks (risk ratio, 3.69; 95% CI: 1.48-9.20).

Discussion: The oral intake was greater in patients whose gastrojejunostomy position in PD was farther from the median, suggesting the necessity of intraoperative placement of the gastrojejunostomy position as far from the median as possible.

Introduction: Preoperative carbohydrate oral (CHO) drinks attenuate the surgical stress response; however, the effects of CHO supplementation on the neutrophil-to-lymphocyte ratio (NLR) as an inflammatory and immunology-based predictor remain unclear. This study evaluated the effects of preoperative CHO loading on NLR values and complications following open colorectal surgery compared with a conventional fasting protocol.

Methods: Sixty eligible participants having planned for routine and open colorectal cancer surgery from May 2020 to January 2022 were prospectively and randomly allocated to either the control (fasting) group, whose members discontinued oral intake beginning the midnight before surgery, or the intervention (CHO) group, whose members consumed a CHO solution the night before surgery and 2 h prior to anaesthesia. NLR was assessed at 06:00 h before surgery (baseline) and at 06:00 h on postoperative days 1, 3, and 5. The incidence and severity of postoperative complications were assessed by Clavien-Dindo Classification up to postoperative day 30. All data were analysed using descriptive statistics.

Results: Postoperative NLR and delta NLR values were significantly higher in controls (p < 0.001; p < 0.001). Control group participants also demonstrated grade IV (n = 5; 16.7%, p < 0.01) and grade V (n = 1; 3.3%, p < 0.313) postoperative complications. There were no major postoperative complications in the CHO group.

Conclusion: Preoperative CHO consumption reduced postoperative NLR values and the incidence and severity of postoperative complications following open colorectal surgery, compared with a preoperative fasting protocol. Preoperative carbohydrate loading may improve recovery following colorectal cancer surgery.

Although rat liver transplantation (LT) is useful in training surgeons to perform microsurgery, mastering these surgical techniques remains difficult. Systematized training protocols that enable learning of the proper skills in a short period of time are needed. The present study describes an efficient five-step rat LT training protocol for surgeons designed to be mastered within 3 months through continuous training. The first step was to review all procedures by watching full videos of rat LT and to watch actual LT operations performed by a skilled surgeon, enabling recognition of the anatomy of rat abdominal organs. The second step was to perform ten donor operations, including ex vivo graft preparation, to learn the atraumatic and delicate techniques. The third step was to perform ten LTs, with the goal of achieving an anhepatic time <20 min and surviving until the next day. The fourth step was to perform ten additional LTs, with the goal of achieving 7 days of survival. The fifth step was to perform 5-10 more LTs, with the goal of achieving 7 days of survival in five consecutive LT operations. Systematizing the training was found to increase its efficiency. Furthermore, determining the specific number of operations in advance is useful to maintain motivation for training. Mastering efficient rat LT will not only enhance the success of preclinical research but will enable young surgeons to better perform vascular anastomoses under a microscope in humans.