Optimization of anastomotic technique and gastric conduit perfusion with hyperspectral imaging and machine learning in an experimental model for minimally invasive esophagectomy

INTRODUCTION

Esophagectomy is the mainstay of esophageal cancer treatment, but anastomotic insufficiency related morbidity and mortality remain challenging for patient outcome. Therefore, the objective of this work was to optimize anastomotic technique and gastric conduit perfusion with hyperspectral imaging (HSI) for total minimally invasive esophagectomy (MIE) with linear stapled anastomosis.

MATERIAL AND METHODS

A live porcine model (n = 58) for MIE was used with gastric conduit formation and simulation of linear stapled side-to-side esophagogastrostomy. Four main experimental groups differed in stapling length (3 vs. 6 cm) and simulation of anastomotic position on the conduit (cranial vs. caudal). Tissue oxygenation around the anastomotic simulation site was evaluated using HSI and was validated with histopathology.

RESULTS

The tissue oxygenation (ΔStO₂) after the anastomotic simulation remained constant only for the short stapler in caudal position (-0.4 ± 4.4%, n.s.) while it was impaired markedly in the other groups (short-cranial: -15.6 ± 11.5%, p = 0.0002; long-cranial: -20.4 ± 7.6%, p = 0.0126; long-caudal: -16.1 ± 9.4%, p < 0.0001). Tissue samples from avascular stomach as measured by HSI showed correspondent eosinophilic pre-necrotic changes in 35.7 ± 9.7% of the surface area.

CONCLUSION

Tissue oxygenation at the site of anastomotic simulation of the gastric conduit during MIE is influenced by stapling technique. Optimal oxygenation was achieved with a short stapler (3 cm) and sufficient distance of the simulated anastomosis to the cranial end of the gastric conduit. HSI tissue deoxygenation corresponded to histopathologic necrotic tissue changes. The experimental model with HSI and ML allow for systematic optimization of gastric conduit perfusion and anastomotic technique while clinical translation will have to be proven.

Robotic colorectal resection in combination with a multimodal enhanced recovery program - results of the first 100 cases

PURPOSE

In Germany, colorectal robot-assisted surgery (RAS) has found its way and is currently used as primary technique in colorectal resections at our clinic. We investigated whether RAS can be extensively combined with enhanced recovery after surgery (ERAS®) in a large prospective patient group.

METHODS

Using the DaVinci Xi surgical robot, all colorectal RAS from 09/2020 to 01/2022 were incorporated into our ERAS® program. Perioperative data were prospectively recorded using a data documentation system. The extent of resection, duration of the operation, intraoperative blood loss, conversion rate, and postoperative short-term results were analyzed. We documented the postoperative duration of Intermediate Care Unit (IMC) stay and major and minor complications according to the Clavien-Dindo classification, anastomotic leak rate, reoperation rate, hospital-stay length, and ERAS® guideline adherence.

RESULTS

One hundred patients (65 colon and 35 rectal resections) were included (median age: 69 years). The median durations of surgery were 167 min (colon resection) and 246 min (rectal resection). Postoperatively, four patients were IMC-treated (median stay: 1 day). In 92.5% of the colon and 88.6% of the rectum resections, no or minor complications occurred postoperatively. The anastomotic leak rate was 3.1% in colon and 5.7% in rectal resection. The reoperation rate was 7.7% (colon resection) and 11.4% (rectal resection). The hospital stay length was 5 days (colon resection) and 6.5 days (rectal resection). The ERAS® guideline adherence rate was 88% (colon resection) and 82.6% (rectal resection).

CONCLUSION

Patient perioperative therapy per the multimodal ERAS® concept is possible without any problems in colorectal RAS, leading to low morbidity and short hospital stays.

Thrombotischer Verschluss der extrakorporalen Zirkulation während hepatischer Chemosaturation trotz zielgerechter Antikoagulation

Die perkutane hepatische Chemosaturation ist eine Behandlungsoption bei nichtresektablen primären oder sekundären Lebertumoren. Dabei wird der Bereich der Lebervenenmündung der Vena cava inferior (VCI) mittels 2 Ballons von der Zirkulation isoliert, sodass die systemische Verteilung des über die Leberarterie applizierten Chemotherapeutikums Melphalan verhindert wird. Nach Passage der Leber und venöser Drainage aus der retrohepatischen VCI durchläuft das chemosaturierte Blut 2 parallel geschaltete extrakorporale Filter. Anschließend wird das gereinigte Blut jugulär rückgeführt. Das Verfahren geht oft mit einer ausgeprägten hämodynamischen Instabilität einher, deren Ursache nicht abschließend geklärt ist. Zusätzlich stellt das Gerinnungsmanagement eine Herausforderung dar. Die Autoren berichten von einem Fall, bei dem sich trotz ausreichender „activated clotting time“ (ACT) ein Thrombus im rückführenden Schenkel der extrakorporalen Zirkulation bildete. Gezielte Problemsuche und -lösung waren parallel zur hämodynamischen Stabilisierung und interdisziplinären Zusammenarbeit notwendig, um die Intervention erfolgreich durchzuführen und der Patientin eine sichere Therapie zukommen zu lassen.

Maternal and Child Health Pipeline Training Programs: A Description of Training Across 6 Funded Programs

Purpose

The HRSA-funded maternal and child health pipeline training programs (MCHPTPs) are a response to the critical need to diversify the MCH workforce, as a strategy to reduce health disparities in MCH populations. These MCHPTPs support students from undergraduate to graduate education and ultimately into the MCH workforce.

Description

The models and components of training across the six MCHPTPs funded in 2016–2021 are summarized, to examine the design and delivery of undergraduate pipeline training and the insights gained across programs.

Assessment

Strategies that emerged across training programs were organized into three themes: recruitment, support for student persistence (in education), and pipeline-to-workforce intentionality. Support for student persistence included financial support, mentoring, creating opportunity for students to develop a sense of belonging, and the use of research as a tool to promote learning and competitiveness for graduate education. Finally, the link to Maternal and Child Health Bureau (MCHB) long-term training and other MCHB opportunities for professional development contributed significant nuance to the pipeline-to-workforce objectives of these programs.

Conclusions

The MCHPTPs not only increase the diversity of the MCH workforce, they also actively prepare the next generation of MCH leaders. The intentional connection of undergraduates to the infrastructure and continuum of MCH training, underscores the comprehensive impact of this funding.

[First 18 months as certified ERAS® center for colorectal cancer : Lessons learned and results of the first 261 patients]

BACKGROUND

Enhanced recovery after surgery (ERAS®) describes a multimodal, interdisciplinary and interprofessional treatment concept that optimizes the postoperative convalescence of the patient through the use of evidence-based measures.

GOAL OF THE WORK

The aim of this article is to present the experiences of our center certified by the ERAS® Society for colorectal resections 18 months after successful implementation.

MATERIAL AND METHODS

Since the beginning of the certification 261 patients have been treated in our clinic according to the specifications of the ERAS® concept. As a comparison group the last 50 patients prior to implementation were evaluated in terms of compliance with ERAS® requirements, length of hospital stay and readmission rate, the need for care in an intensive or intermediate care ward, the number of necessary reoperations and the complication rate.

RESULTS

Compliance increased from 39.3% preERAS® to 81.1% after ERAS® implementation (p < 0.001). At the same time the length of stay of ERAS® patients was reduced from 7 days to 5 days (p = 0.001). While the rate of surgical complications was the same between the two groups (p = 0.236), nonsurgical complications occurred significantly less frequently in the ERAS® cohort (p = 0.018).

DISCUSSION

There are well-known stumbling blocks in implementing and maintaining an ERAS® concept; however, it is worthwhile for the patient to circumnavigate this and establish ERAS® as the standard treatment path.

Bedside hyperspectral imaging indicates a microcirculatory sepsis pattern - an observational study

INTRODUCTION

Microcirculatory alterations are key mechanisms in sepsis pathophysiology leading to tissue hypoxia, edema formation, and organ dysfunction. Hyperspectral imaging (HSI) is an emerging imaging technology that uses tissue-light interactions to evaluate biochemical tissue characteristics including tissue oxygenation, hemoglobin content and water content. Currently, clinical data for HSI technologies in critical ill patients are still limited.

METHODS AND ANALYSIS

TIVITA® Tissue System was used to measure Tissue oxygenation (StO2), Tissue Hemoglobin Index (THI), Near Infrared Perfusion Index (NPI) and Tissue Water Index (TWI) in 25 healthy volunteers and 25 septic patients. HSI measurement sites were the palm, the fingertip, and a suprapatellar knee area. Septic patients were evaluated on admission to the ICU (E), 6 h afterwards (E+6) and three times a day (t3-t9) within a total observation period of 72 h. Primary outcome was the correlation of HSI results with daily SOFA-scores.

RESULTS

Serial HSI at the three measurement sites in healthy volunteers showed a low mean variance expressing high retest reliability. HSI at E demonstrated significantly lower StO2 and NPI as well as higher TWI at the palm and fingertip in septic patients compared to healthy volunteers. StO2 and TWI showed corresponding results at the suprapatellar knee area. In septic patients, palm and fingertip THI identified survivors (E-t4) and revealed predictivity for 28-day mortality (E). Fingertip StO2 and THI correlated to SOFA-score on day 2. TWI was consistently increased in relation to the TWI range of healthy controls during the observation time. Palm TWI correlated positively with SOFA scores on day 3.

DISCUSSION

HSI results in septic patients point to a distinctive microcirculatory pattern indicative of reduced skin oxygenation and perfusion quality combined with increased blood pooling and tissue water content. THI might possess risk-stratification properties and TWI could allow tissue edema evaluation in critically ill patients.

CONCLUSION

HSI technologies could open new perspectives in microcirculatory monitoring by visualizing oxygenation and perfusion quality combined with tissue water content in critically ill patients - a prerequisite for future tissue perfusion guided therapy concepts in intensive care medicine.

[Perioperative fluid management in major abdominal surgery]

Intravascular fluid administration belongs to the cornerstones of perioperative treatment with a substantial impact on surgical outcome especially with respect to major abdominal surgery. By avoidance of hypovolemia and hypervolemia, adequate perioperative fluid management significantly contributes to the reduction of insufficient tissue perfusion as a determinant of postoperative morbidity and mortality. The effective use of intravascular fluids requires detailed knowledge of the substances as well as measures to guide fluid therapy. Fluid management already starts preoperatively and should be continued in the postoperative setting (recovery room, peripheral ward) considering a patient-adjusted and surgery-adjusted hemodynamic monitoring. Communication between all team members participating in perioperative care is essential to optimize fluid management.

Efficacy of antiseptics in a novel 3-dimensional human plasma biofilm model (hpBIOM)

The increasing incidence of non-healing wounds constitutes a pivotal socio-economic burden. 60-80% of chronic wounds are colonized by pathogenic microorganisms within a protective extracellular polymeric substance, bearing a great challenge in wound management. Human plasma was used to prepare the biofilm model (hpBIOM), adding pathogens to the plasma and forming Coagula-like discs with integrated pathogens were produced. The antiseptics Octenisept and Lavasorb were tested regarding their antibacterial properties on clinically relevant biofilm-growing bacteria (MRSA, P. aeruginosa) in the hpBIOM. Biofilm-typical glycocalyx-formation was confirmed using immunohistochemical staining. Treatment of a 12 h-maturated biofilm with Octenisept resulted in complete eradication of P. aeruginosa and MRSA after 48 h. Lavasorb proved less effective than Octenisept in this setting. In more mature biofilms (24 h), both antiseptics showed a delayed, partially decreased efficacy. Summarized, the hpBIOM provides essential factors for a translational research approach to be used for detailed human biofilm analyses and evaluation of antimicrobial/-biofilm properties of established and novel therapeutic strategies and products. Octenisept and Lavasorb showed an attenuated efficacy in the hpBIOM compared to planktonic conditions and previously published biofilm-studies, prompting the question for the necessity of introducing new international standards and pre-admission requirements on a translational base.

SUN-097 AgRP Neurons Determine Survival in Activity-Based Anorexia Model

Anorexia Nervosa (AN) is an eating disorder characterized by severe hypophagia, high levels of physical activity, harsh weight loss and an intense fear of weight gain. It has the highest mortality rate among psychiatric illnesses and, due to the unknown underlying neurobiology, it is challenging to treat. Agouti-related protein (AgRP) neurons, which are localized in the arcuate nucleus in the hypothalamus, are both necessary and sufficient or feeding in adult animals.To uncover new neural circuits that may contribute towards vulnerability to AN or might be affected by AN, we employed the specific diphtheria toxin receptor-expressing mice (AgRP-DTR) which, by the selective ablation of AgRP neurons, allow to test the impact of an impaired AgRP circuit function under the activity-based anorexia (ABA) paradigm. ABA is a bio-behavioral phenomenon described in rodents and refers to the weight loss, hypophagia and paradoxical hyperactivity that develops in rodents exposed to running wheels and restricted food access, and provides a model for the key symptoms of AN. Mice that express DTR only in AgRP neurons and subcutaneously injected with diphtheria toxin (DTX) at postnatal day 3 lost more than 50% of AgRP neurons on postnatal day 7 compared to control. The same percentage of neuronal loss was detected in 8 weeks old mice. In addition, the neonatal animals developed normally after AgRP ablation, did not show any phenotypic effects and maintained normal food intake and weight when fed ad libitum. On postnatal day 36 (P36), males and females animals were housed with access on a running wheel and fed ad libitum for 4 days (acclimation phase). On P40, for 72 hours animals were fed for only two hours daily. Following the fasting phase, free access to food was returned and the running wheel was removed. Continuous multi-day analysis of running wheel activity showed that both controls and AgRP-DTR mice kept constant weight and food intake during acclimation. In contrast, although mice became hyperactive within the 24 hours following the onset of food restriction (FR), we noted a 10% mortality on day 2 and 70% mortality at day 4 among the AgRP DTR mice. Moreover, the survived AgRP-DTR mice failed to return to normal food intake and weight even when ad libitum food was provided. Overall, AgRP neurons showed to be crucial for the full development of ABA symptoms. The results suggest that our new experimental setting is able to correlate particular neurons populationto vulnerability, onset and progression of anorexia nervosa.

Elevated Thrombomodulin Plasma Levels as a Result of Endothelial Involvement in Plasmodium falciparum Malaria

We used thrombomodulin (TM) to assess the participation of the vascular endothelium in human Plasmodium falciparum (P. F.) malaria. Before therapy TM plasma levels were elevated in P. F. malaria and fell to normal values during therapy. Parasitemia, TNFα, elastase and TAT levels correlated directly with TM. Elevated TM levels can not be explained by increased synthesis, since incubating HUVEC with pretherapy serum of patients with P. F. malaria, but not reconvalescence serum, suppressed TM transcription. This was partially prevented by adding a TNFα neutralizing antibody to patient serum before incubation with HUVEC. However, TNFα does not release TM from cultured HUVEC in vitro. Coincubation of HUVEC with pretherapy serum together with neutrophils resulted in endothelial cell destruction, which could be partly prevented by a TNFα neutralizing antibody. Hence the increase of TM during P. F. malaria might reflect the concerted action of cytokines and neutrophils on HUVEC.

Antiparasitic Treatment of Patients with P. falciparum Malaria Reduces the Ability of Patient Serum to Induce Tissue Factor by Decreasing NF-κB Activation

Serum from patients with P. falciparum malaria at day 1 (pretherapy) induces tissue factor (TF) in cultured endothelial cells. TF induction depends on de novo transcription as shown in Nuclear Run On assays. Electrophoretic mobility shift assays demonstrated binding of AP-1 and NF- κB/Rel proteins to their recognition sites in the TF promotor. After therapy (day 28), stimulation of TF antigen by patient serum is reduced by 70%. When serum obtained before and after therapy was compared, a decrease of NF-κB activation was evident. Activation of NF-κB-like proteins was in part dependent on TNFα in patient serum, since a TNFα neutralizing antibody reduced induction of TF transcription and translation and induction of NF-κB-like proteins. Induction of TF activity was suppressed by pDTC, an inhibitor of NF-κB activation. When different promotor constructs of the TF gene were tested, induction was dependent upon the presence of the intact NF-κB-like binding site in the TF promotor. A mutant with deleted NF-κB, but intact AP-1 sites was not inducible. Mutation of the AP-1 sites did not prevent induction, but reduced inducibility by pretherapy serum. Therefore, NF-κB/Rel proteins are responsible for induction of TF transcription by pretherapy serum, but AP-1 is needed for highest inducibility. The effect of antiparasitic therapy on the induction of TF by serum from patients with complicated P. falciparum malaria is dependent on a therapy-mediated loss of activation of NF-κB-like proteins in post-treatment patient serum.

Tetracycline alters gene expression in Salmonella strains that harbor the Tn10 transposon

In this report, we show that bacterial plasmids that harbor the Tn10 transposon (i.e., the IncHI1 plasmid R27) modify expression of different Salmonella regulons responding to the presence of tetracycline (Tc) in the medium. By using as a model the Tc-dependent upregulation of the ibpAB operon (which belongs to the heat shock regulon), we have identified Tn10-tetA (coding for a Tc efflux pump) and adjacent tetC sequences as required for ibpAB upregulation. Characterization of transcripts in the tetAC region showed that tetA transcription can continue into tetC sequences, generating a long 3'UTR sequence, which can protect transcripts from RNA processing, thus increasing the expression of TetA protein. In the presence of Tc, the DnaK and IbpA chaperones are overexpressed and translocated to the periplasm and to the membrane fraction respectively. DnaK targeting unfolded proteins is known to induce heat shock by avoiding RpoH proteolysis. We correlate expression levels of Tn10-encoded TetA protein with heat shock induction in Salmonella, likely because TetA activity compromises protein secretion.

Systematically assessed symptoms as outcome predictors in emergency patients

INTRODUCTION

It is known that symptoms are predictive of mortality in "nonsurgical" emergency patients. It is unknown whether a prospective, systematic, and "unscreened" assessment of all symptoms is of any prognostic value. Therefore, we aimed to examine the association between symptoms and outcomes in an all-comer population.

METHODS

Data were acquired during 6weeks at the ED of the University Hospital Basel, a tertiary hospital. Consecutive patients presenting to the ED were included. Symptoms at presentation were systematically assessed using a comprehensive questionnaire.

RESULTS

A consecutive sample of 3960 emergency patients with a median age of 51years (51.7% male) was studied. The median number of symptoms was two. In the group of patients with the most prevalent symptoms, the median number of symptoms ranged between two and five. Overall, hospitalisation rate was 31.2%, referral to intensive care was 5.5%, in-hospital-mortality was 1.4%, and one-year mortality was 5.8%. In-hospital mortality ranged from 0% to 4.3%, and one-year mortality from 0% to 14.4% depending on the presenting symptoms. Dyspnoea and weakness were significant predictors of one-year mortality (14.4% and 9.2%, respectively).

DISCUSSION

Most emergency patients indicated two or more symptoms. Systematically assessed symptoms at presentation can be used for prediction of outcomes. While dyspnoea is a known predictor, weakness has not been identified as predictor of mortality before. This knowledge could be used to improve risk stratification- thereby reducing the risk of adverse outcomes.

Abstract OT3-07-01: A randomized trial evaluating bioimpedance spectroscopy vs. tape measurement in the prevention of lymphedema following breast cancer treatment

Background: Breast cancer related lymphedema (BCRL) represents a common treatment associated complication following surgery, radiation and/or chemotherapy. Increasing data has demonstrated the ability of new diagnostic modalities to detect BCRL in the subclinical phase of the process allowing for early intervention.

Trial Design: This 2-group stratified randomized clinical trial evaluates the effectiveness of bioimpedance spectroscopy (BIS) for early detection and prevention of BCRL compared to tape measurement (TM). Baseline assessments are made pre-operatively. Two-months post-op, patients are censored out if they have developed any of the exclusion conditions, did not have a mastectomy, axillary dissection, &gt;6 sentinel nodes removed, radiation therapy, or taxane. Remaining patients are randomized within site to either BIS or TM; monitored at 3 to 6-month intervals up to 36-months post-op for a change over baseline specified to trigger a compression sleeve & gauntlet intervention. Cohort trigger thresholds are change of ≥10 L-Dex units or 5 to &lt;10% volume. If the intervention is triggered, measurements by the other method are taken before initiating the 4-week intervention. Post intervention, patients are monitored only with TM. Volume change of ≥10% results in study removal and physician referral. At the 2 study endpoints (36 month visit or volume change of ≥10%) measurements are taken with each method.

Eligibility Criteria: Inclusion criteria: ≥ 18 with histologically confirmed stage I-III breast cancer (BC) or DCIS with planned surgery. Exclusion criteria include history of BC therapy or lymphedema.

Specific Aims: The primary hypothesis is that subclinical detection of BCRL with BIS and early intervention will reduce the rate of lymphedema progression (as measured by referral to complex decongestive physiotherapy) compared to TM. Secondary outcomes include BCRL risk factors, quality of life, and time to treatment.

Statistical Methods: Sample size and powering were based on the hypothesis that BIS would reduce progression rate by 20%. A rate of 50% progression in the TM group was used as the standard. 1100 patients will be enrolled to result in randomized groups of 100 (Total N=200) Statistics include relative risks with respective bootstrapped 95% C.I. and Cochran-Mantel-Haenszel tests.

Present Accrual and Target Accrual: Overall, the study target or expected enrollment as of the end of March 31, 2016 was 690 participants, 534 were actually enrolled (actual accrual 77% of target). Accrual at the study sites ranged from 15 to 104% of target.

Contact Information: Sheila Ridner: 615-322-0831, Sheila.ridner@vanderbilt.edu

Support: ImpediMed Limited, ImpediMed, Inc. and medi USA.

Citation Format: Ridner S, Shah C, Dietrich M, Vicini F. A randomized trial evaluating bioimpedance spectroscopy vs. tape measurement in the prevention of lymphedema following breast cancer treatment [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT3-07-01.