Mitral Regurgitation Complicated by Cardiogenic Shock: Reassessing Risk Stratification and Therapeutic Strategies

Mitral regurgitation complicated by cardiogenic shock creates a unique and devastating risk profile for patients and poses significant difficulties for physicians who lack a comprehensive range of effective management strategies. Supportive measures such as intravenous vasodilators, intra-aortic balloon pumps, and percutaneous ventricular assist devices are often necessary to stabilize patients prior to definitive treatment with surgical mitral valve replacement or trans-catheter edge-to-edge repair. This review evaluates the evidence for the available supportive and definitive management strategies in patients with mitral regurgitation complicated by cardiogenic shock and presents a framework to aid clinicians in navigating the complex clinical decision-making process. Additionally, the authors review emerging transcatheter mitral valve replacement technologies that hold promise for expanding the therapeutic armamentarium and improving patient outcomes.

Comprehensive Quality of Life Report from a Prospective Clinical Trial of 4DCT-Ventilation Functional Lung Avoidance Radiation Therapy

PURPOSE/OBJECTIVE(S)

Functional imaging has been developed that uses 4DCT images and image processing to generate lung ventilation maps (4DCT-ventilation). 4DCT-ventilation functional avoidance uses 4DCT-images to generate plans that avoid functional regions of the lung with the goal of reducing pulmonary toxicity. A 4DCT-ventilation functional avoidance, phase II, multi-center clinical trial was completed, and patient reported outcomes (PRO) measured. PROs are an essential measure of quality-of-life following radiotherapy. The purpose of this work is to quantify PRO changes for lung cancer patients treated with functional avoidance and to compare PROs against clinical pneumonitis.

MATERIALS/METHODS

Patients with locally advanced lung cancer receiving curative intent radiotherapy (prescriptions of 45-75 Gy) and chemotherapy were accrued. Each patient had a 4DCT-ventilation image generated using 4DCT data. Favorable arc geometry and optimization techniques were used to generate functional avoidance plans. PRO instruments included the Functional Assessment of Cancer Therapy Lung (FACT-L) questionnaire and the Visual Analog Scale (VAS) administered pre-treatment and 3-, 6-, and 12-months post-treatment to gather data on physical, social, emotional, functional, and pulmonary well-being. The percentage of patients with clinically significant decline was calculated using the FACT-TOI (Trial Outcome Index), FACT-LCS (Lung Cancer Subscale), and VAS instruments. To evaluate the correlation between PROs and clinical toxicity, the percentage of clinically significant FACT-LCS decline was compared (Chi-square test) for patients who did or did not experience grade 2+ pneumonitis.

RESULTS

Fifty-nine patients completed baseline PRO surveys. Median age was 65, 83% of patients had non-small-cell lung cancer, with 75% having stage III disease. Clinically significant FACT-TOI decline at, 3, 6, and 12 months was 46.3%, 38.5%, and 26.8%, respectively. The percentage of patients with clinically significant FACT-LCS decline was 33.3%, 33.3%, and 29.3%, at 3 months, 6 months, and 12 months, respectively. The percentage of patients with clinically significant VAS decline at 3, 6, and 12 months was 18.9%, 20.0%, and 18.6%, respectively. Patients who experienced grade 2+ pneumonitis had a greater percentage of clinically significant decline at all time-points with the results reaching significance (p = 0.045) at 6 months.

CONCLUSION

The study presents the first comprehensive evaluation of PROs for patients treated with 4DCT-ventilation functional avoidance. The data show that 20-40% of patients had clinically significant decline and that PROs had a strong correlation with pneumonitis. The PRO data demonstrate that functional avoidance results in low rates of patient reported outcome clinical decline and provide seminal results to be used in phase III studies.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

CCR5 Receptor Occupancy Analysis Reveals Increased Peripheral Blood CCR5+CD4+ T Cells Following Treatment With the Anti-CCR5 Antibody Leronlimab

CCR5 plays a central role in infectious disease, host defense, and cancer progression, thereby making it an ideal target for therapeutic development. Notably, CCR5 is the major HIV entry co-receptor, where its surface density correlates with HIV plasma viremia. The level of CCR5 receptor occupancy (RO) achieved by a CCR5-targeting therapeutic is therefore a critical predictor of its efficacy. However, current methods to measure CCR5 RO lack sensitivity, resulting in high background and overcalculation. Here, we report on two independent, flow cytometric methods of calculating CCR5 RO using the anti-CCR5 antibody, Leronlimab. We show that both methods led to comparable CCR5 RO values, with low background on untreated CCR5+CD4+ T cells and sensitive measurements of occupancy on both blood and tissue-resident CD4+ T cells that correlated longitudinally with plasma concentrations in Leronlimab-treated macaques. Using these assays, we found that Leronlimab stabilized cell surface CCR5, leading to an increase in the levels of circulating and tissue-resident CCR5+CD4+ T cells in vivo in Leronlimab-treated macaques. Weekly Leronlimab treatment in a chronically SIV-infected macaque led to increased CCR5+CD4+ T cells levels and fully suppressed plasma viremia, both concomitant with full CCR5 RO on peripheral blood CD4+ T cells, demonstrating that CCR5+CD4+ T cells were protected from viral replication by Leronlimab binding. Finally, we extended these results to Leronlimab-treated humans and found that weekly 700 mg Leronlimab led to complete CCR5 RO on peripheral blood CD4+ T cells and a statistically significant increase in CCR5+CD4+ T cells in peripheral blood. Collectively, these results establish two RO calculation methods for longitudinal monitoring of anti-CCR5 therapeutic antibody blockade efficacy in both macaques and humans, demonstrate that CCR5+CD4+ T cell levels temporarily increase with Leronlimab treatment, and facilitate future detailed investigations into the immunological impacts of CCR5 inhibition in multiple pathophysiological processes.

EP.FRI.1020 The necessity of colonoscopy to rule out colorectal malignancy after computerised tomography proven diagnosis of acute diverticulitis

Introduction

The current Royal College of Surgeons commissioning guideline on colonic diverticular disease suggests that patients should undergo endoscopic evaluation of the colonic lumen after an episode of computed tomography (CT) proven acute diverticulitis to rule out malignancy. The necessity of routine endoscopic assessment of CT proven diverticulitis remains debatable.

Aim

To establish whether routine endoscopic assessment should be carried out for patients after an episode of acute diverticulitis.

Method

Data was collected retrospectively from all patients diagnosed with acute diverticulitis on CT and who subsequently had follow up endoscopic assessment from January to July 2019.

Results

Total number of patients were 64.Median age of the cohort was 58.Of all patients, 48 had diagnosis of uncomplicated diverticulitis whereas 16 patients had diagnosis of complicated diverticulitis on CT scan. All patients had follow up colonoscopy after an acute attack with following findings: 2 patients had no pathology, 56 patients had diagnosis of only diverticulosis, 4 patients had both diverticulosis and polyps and 2 patients had bowel cancer. All 4 cases of polyps had benign pathology and uncomplicated diverticulitis on CT scan. Two bowel cancer patients, one had complicated diverticulitis with thickening of proximal sigmoid and the other patient had abnormal sigmoid colon suggestive of malignancy on CT scan.

Conclusion

Recent meta-analysis showed no difference between diverticulitis and normal population group in terms of risk of bowel cancer. Routine colonoscopy may not be appropriate in patients with acute uncomplicated diverticulitis but endoscopic assessment after an episode of complicated diverticulitis is necessary.

219 Have New National Guidelines Changed Practice in Referrals with Suspected Ureteric Colic?

Aim

To assess how many patients had a non-contrast CT as first-line investigation for suspected renal colic, and how this was affected by the release of the 2019 NICE guidelines. A secondary aim was to assess the proportion of patients who had CT KUBs that demonstrated a ureteric calculus.

Method

CT KUB scans performed over two separate 3 month periods were identified. These reflected periods of time before and after the new NICE guidelines. Electronic records were used to assess if the patients had an ultrasound performed as the initial diagnostic investigation, instead of a CT scan. The results of the scans were reviewed to identify if a ureteric or renal calculus had been positively identified.

Results

In the period before the new guidelines, 61 patients were scanned. 4 had an ultrasound to assess for a stone prior to a CT. All of these patients were medical inpatients. None of the ultrasounds diagnosed a stone. 22/61 patients had CT-proven stones (36%) In the period after the new guidelines, 79 patients were scanned. 12 had an ultrasound to assess for a stone prior to a CT. 8 were medical patients, 3 were surgical and 1 was gynaecological. 1 ultrasound diagnosed a stone. 28/79 patients had CT-proven stones (35.4%)

Conclusions

The release of new guidelines did not improved compliance with suggested imaging pathways. This clearly demonstrates an area for improvement. It is also worth noting that only 1/3 of referrals with suspected renal colic did actually have a stone, which has implications for specialty referral pathways.

218 The Impact on Minimally Invasive Urological Cancer Surgery During the Covid-19 Pandemic

Aim

Learned bodies recommended restricted use of, or extensive precautions when using, laparoscopic/robotic surgery during the Covid-19 pandemic. We aimed to determine whether minimally invasive surgery (MIS) in uro-oncology patients was safe for patients and staff.

Method

From 16 March to 16 June 2020, patients having MIS in a tertiary referral urology centre were identified from a prospectively collected database. Patient characteristics, operative details and 30-day follow-up for adverse events were recorded including Covid-19 tests and results. Any theatre staff Covid-19 event was traced back 14 days to determine any involvement in these cases.

Results

87 patients were eligible for inclusion (33 robotic prostatectomies, 38 laparoscopic prostatectomies, 11 laparoscopic nephrectomies, 5 robotic nephrectomies). All patients were assessed for symptoms of Covid-19 on the day of theatre. 18(21%) patients had pre-operative screening (all swabs, no CT chest). 46(53%) underwent 14 days pre-operative self-isolation. 38(44%) cases were performed with FFP3 protection. No modification to operating procedure was made for any cases. No patients tested positive for Covid-19 in the 30-day postoperative period. No staff member involved tested positive in the postoperative period. 1 patient tested positive pre-operatively, delaying the operation by 7 weeks. No patients tested positive after the introduction of mandatory screening.

Conclusions

Based on our case-series MIS urological surgery appears to be safe for patients and staff, with no increased risk of Covid-19 complications in patients who are asymptomatic pre-operatively. The introduction of mandatory pre-operative swabs for elective patients, and the use of FFP3 protection, did not significantly alter results.

367 Improving Handover Documentation in Surgical Inpatients Using Weekend Handover Stickers

Introduction

Transfer to the care to the oncoming team is the point at which inpatients are most vulnerable. Effective handover is vital to protect patient safety and clinical governance. The Royal College of Surgery (RCS) Safe Handover guidelines highlight relevant information required for comprehensive handover. This QI project aimed to determine if implementation of weekend handover stickers in surgical patients’ notes improved handover documentation.

Method

A retrospective records-based audit of patients admitted under general surgery over a 4-week period was performed. Standards were set using the RCS guidelines to determine if sufficient weekend handover was documented.

We designed weekend handover stickers to be inserted in notes based on guidelines. A re-audit cycle over a 4-week period was performed to determine if the intervention improved handover documentation.

Results

119 patients were in the initial audit. 125 patients were in the re-audit. Documented handover in the notes improved from 43.7% to 89.6% after intervention.

Documentation of the following clinical information also improved: clinical situation (43.7% to 92.0%); co-morbidities (14.3% to 89.6%); current issues (71.4% to 94.4%); weekend blood tests (32.8% to 92.0%); antibiotic therapy (21.8% to 92.0%).

Conclusions

Weekend handover stickers resulted in a significant improvement in handover documentation improving patient safety.

A Modified AUGIS Delphi Process to Establish Future Research Priorities in Benign Upper Gastrointestinal Surgery

BACKGROUND

The aim of our study was to use a modified Delphi process to determine the research priorities amongst benign upper gastrointestinal (UGI) surgeons in the United Kingdom.

METHODS

Delphi methodology may be utilised to develop consensus opinion amongst a group of experts. Members of the Association of Upper Gastrointestinal Surgeons of Great Britain and Ireland were invited to submit individual research questions via an online survey (phase I). Two rounds of prioritisation by multidisciplinary expert healthcare professionals (phase II and III) were completed to determine a final list of high-priority research questions.

RESULTS

Four hundred and twenty-seven questions were submitted in phase I, and 51 with a benign UGI focus were taken forward for prioritisation in phase II. Twenty-eight questions were ranked in phase III. A final list of 11 high-priority questions had an emphasis on acute pancreatitis, Barrett's oesophagus and benign biliary disease.

CONCLUSION

A modified Delphi process has produced a list of 11 high-priority research questions in benign UGI surgery. Future studies and awards from funding bodies should reflect this consensus list of prioritised questions in the interest of improving patient care and encouraging collaborative research.

Measurements of the Thermal Resistivity of InAlAs, InGaAs, and InAlAs/InGaAs Superlattices

Thermal management efforts in nanoscale devices must consider both the thermal properties of the constituent materials and the interfaces connecting them. It is currently unclear whether alloy/alloy semiconductor superlattices such as InAlAs/InGaAs have lower thermal conductivities than their constituent alloys. We report measurements of the crossplane thermal resistivity of InAlAs/InGaAs superlattices at room temperature, showing that the superlattice resistivities are larger by a factor of 1.2-1.6 than that of the constituent bulk materials, depending on the strain state and composition. We show that the additional resistance present in these superlattices can be tuned by a factor of 2.5 by altering the lattice mismatch and thereby the phonon-mode mismatch at the interfaces, a principle that is commonly assumed for superlattices but has not been experimentally verified without adding new elements to the layers. We find that the additional resistance in superlattices does not increase significantly when the layer thickness is decreased from 4 to 2 nm. We also report measurements of 250-1000 nm thick films of undoped InGaAs and InAlAs lattice-matched to InP substrates, for there is no published thermal conductivity value for the latter, and we find it to be 2.24 ± 0.09 at 22 °C, which is ∼2.7 times smaller than the widely used estimates.

Evaluation of healing in feline femoral defects filled with cancellous autograft, cancellous allograft or Bioglass

Cancellous bone grafting is a widely accepted technique in human and veterinary orthopaedic surgery. However, the use of autogenous bone graft is limited by the additional surgical time required to harvest the graft, the morbidity associated with the donor site, and the limited availability of cancellous bone, especially in feline patients. Various allografts and bone graft substitutes are available commercially but have not been fully evaluated for efficacy in the cat. The purpose of this study was to compare the incorporation of autogenous and allogenous cancellous bone graft and Bioglass®, a synthetic bone graft substitute, in femoral defects in cats. Four (4.0 mm diameter) defects were created in the lateral diaphyseal cortex of the left femur with an orthopaedic drill. In each femur, one of the cortical defects was filled with autogenous cancellous graft (harvested from the tibia), one was filled with allogenic cancellous graft, and one was filled with Bioglass. The fourth defect remained unfilled. Graft incorporation within the femoral defects was evaluated by radiographic evaluation every two weeks. Six weeks after the grafting procedure, the cats were euthanatized and high detailed radiography, dual energy X-ray absorptiometry (DEXA), histopathology and histomorphometry of the defects were performed. Satisfactory bone healing was observed within all of the defects.

Comfort and performance of power line maintainers' gloves during electrical utility work in the cold

BACKGROUND

Electrical utility workers wear thick rubber gloves and often work in the cold.

OBJECTIVE

To document the challenge of working in the cold and the effectiveness of different glove/liner combinations in keeping workers' hands warm.

METHODS

Ten experienced male electrical utility employees worked in a controlled temperature walk-in chamber at -20 °C for 45 minutes for each of five glove conditions: standard five-finger rubber gloves with cotton liners and gauntlets, mitten style gloves, a prototype wool liner, and two heating options; glove or torso. Dependent measures were maximum grip force, skin temperatures, finger dexterity and sensitivity to touch, ratings of perceived effort and a rating of thermal sensation.

RESULTS

Participants' hand skin temperatures decreased, they perceived their hands to be much colder, their finger sensitivity decreased and their ratings of perceived exertion increased, however their performance did not degrade over the 45 minute trials. The mitten-style gloves showed a smaller drop in skin temperature for the 3rd and 5th digits (p< 0.05) than the other glove conditions.

CONCLUSIONS

Mitten style gloves kept workers' hands warmer than the standard five finger glove.