Evaluation of neuraxial analgesia on outcomes for patients undergoing robot assisted abdominal surgery

STUDY OBJECTIVE

Following robot assisted abdominal surgery, the pain can be moderate in severity. Neuraxial analgesia may decrease the activity of the detrusor muscle, reduce the incidence of bladder spasm and provide effective somatic and visceral analgesia. In this systematic review, we assessed the role of neuraxial analgesia in robot assisted abdominal surgery.

DESIGN

Systematic review.

SETTINGS

Robot assisted abdominal surgery.

PATIENTS

Adults.

INTERVENTIONS

Subsequent to a search of the electronic databases, observational studies and randomized controlled trials that assessed the effect of neuraxial analgesia instituted at induction of anesthesia or intraoperatively in adult and robot assisted abdominal surgery were considered for inclusion. The outcomes of observational studies as well as randomized controlled trials which were not subjected to meta-analysis were presented in descriptive terms. Meta-analysis was conducted if an outcome of interest was reported by two or more randomized controlled trials.

MAIN RESULTS

We included 19 and 11 studies that investigated spinal and epidural analgesia in adults, respectively. The coprimary outcomes were the pain score at rest at 24 h and the cumulative intravenous morphine consumption at 24 h. Spinal analgesia with long acting neuraxial opioid did not decrease the pain score at rest at 24 h although it reduced the cumulative intravenous morphine consumption at 24 h by a mean difference (95%CI) of 14.88 mg (-22.13--7.63; p < 0.0001, I2 = 50%) with a low and moderate quality of evidence, respectively, on meta-analysis of randomized controlled trials. Spinal analgesia with long acting neuraxial opioid had a beneficial effect on analgesic indices till the second postoperative day and a positive influence on opioid consumption up to and including the 72 h time point. The majority of studies demonstrated the use of spinal analgesia with long acting neuraxial opioid to lead to no difference in the incidence of postoperative nausea and vomiting, and the occurrence of pruritus was found to be increased with spinal analgesia with long acting neuraxial opioid in recovery but not at later time points. No difference was revealed in the incidence of urinary retention. The evidence in regard to the quality of recovery-15 score at 24 h and hospital length of stay was not fully consistent, although most studies indicated no difference between spinal analgesia and control for these outcomes. Epidural analgesia in robot assisted abdominal surgery was shown to decrease the pain on movement at 12 h but it had not been studied with respect to its influence on the pain score at rest at 24 h or the cumulative intravenous morphine consumption at 24 h. It did not reduce the pain on movement at later time points and the evidence related to the hospital length of stay was inconsistent.

CONCLUSIONS

Spinal analgesia with long acting neuraxial opioid had a favourable effect on analgesic indices and opioid consumption, and is recommended by the authors, but the evidence for spinal analgesia with short acting neuraxial opioid and epidural analgesia was limited.

Prostate Cancer, Version 3.2024

The NCCN Guidelines for Prostate Cancer include recommendations for staging and risk assessment after a prostate cancer diagnosis and for the care of patients with localized, regional, recurrent, and metastatic disease. These NCCN Guidelines Insights summarize the panel's discussions for the 2024 update to the guidelines with regard to initial risk stratification, initial management of very-low-risk disease, and the treatment of nonmetastatic recurrence.

Deep learning based automatic segmentation of the Internal Pudendal Artery in definitive radiotherapy treatment planning of localized prostate cancer

Background and purpose

Radiation-induced erectile dysfunction (RiED) commonly affects prostate cancer patients, prompting clinical trials across institutions to explore dose-sparing to internal-pudendal-arteries (IPA) for preserving sexual potency. IPA, challenging to segment, isn't conventionally considered an organ-at-risk (OAR). This study proposes a deep learning (DL) auto-segmentation model for IPA, using Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) or CT alone to accommodate varied clinical practices.

Materials and methods

A total of 86 patients with CT and MRI images and noisy IPA labels were recruited in this study. We split the data into 42/14/30 for model training, testing, and a clinical observer study, respectively. There were three major innovations in this model: 1) we designed an architecture with squeeze-and-excite blocks and modality attention for effective feature extraction and production of accurate segmentation, 2) a novel loss function was used for training the model effectively with noisy labels, and 3) modality dropout strategy was used for making the model capable of segmentation in the absence of MRI.

Results

Test dataset metrics were DSC 61.71 ± 7.7 %, ASD 2.5 ± .87 mm, and HD95 7.0 ± 2.3 mm. AI segmented contours showed dosimetric similarity to expert physician's contours. Observer study indicated higher scores for AI contours (mean = 3.7) compared to inexperienced physicians' contours (mean = 3.1). Inexperienced physicians improved scores to 3.7 when starting with AI contours.

Conclusion

The proposed model achieved good quality IPA contours to improve uniformity of segmentation and to facilitate introduction of standardized IPA segmentation into clinical trials and practice.

Simulation and pre-planning omitted radiotherapy (SPORT): a feasibility study for prostate cancer

This study explored the feasibility of on-couch intensity modulated radiotherapy (IMRT) planning for prostate cancer (PCa) on a cone-beam CT (CBCT)-based online adaptive RT platform without an individualized pre-treatment plan and contours. Ten patients with PCa previously treated with image-guided IMRT (60 Gy/20 fractions) were selected. In contrast to the routine online adaptive RT workflow, a novel approach was employed in which the same preplan that was optimized on one reference patient was adapted to generate individual on-couch/initial plans for the other nine test patients using Ethos emulator. Simulation CTs of the test patients were used as simulated online CBCT (sCBCT) for emulation. Quality assessments were conducted on synthetic CTs (sCT). Dosimetric comparisons were performed between on-couch plans, on-couch plans recomputed on the sCBCT and individually optimized plans for test patients. The median value of mean absolute difference between sCT and sCBCT was 74.7 HU (range 69.5-91.5 HU). The average CTV/PTV coverage by prescription dose was 100.0%/94.7%, and normal tissue constraints were met for the nine test patients in on-couch plans on sCT. Recalculating on-couch plans on the sCBCT showed about 0.7% reduction of PTV coverage and a 0.6% increasing of hotspot, and the dose difference of the OARs was negligible (<0.5 Gy). Hence, initial IMRT plans for new patients can be generated by adapting a reference patient's preplan with online contours, which had similar qualities to the conventional approach of individually optimized plan on the simulation CT. Further study is needed to identify selection criteria for patient anatomy most amenable to this workflow.

Mapping Cellular Interactions from Spatially Resolved Transcriptomics Data

Cell-cell communication (CCC) is essential to how life forms and functions. However, accurate, high-throughput mapping of how expression of all genes in one cell affects expression of all genes in another cell is made possible only recently, through the introduction of spatially resolved transcriptomics technologies (SRTs), especially those that achieve single cell resolution. However, significant challenges remain to analyze such highly complex data properly. Here, we introduce a Bayesian multi-instance learning framework, spacia, to detect CCCs from data generated by SRTs, by uniquely exploiting their spatial modality. We highlight spacia's power to overcome fundamental limitations of popular analytical tools for inference of CCCs, including losing single-cell resolution, limited to ligand-receptor relationships and prior interaction databases, high false positive rates, and most importantly the lack of consideration of the multiple-sender-to-one-receiver paradigm. We evaluated the fitness of spacia for all three commercialized single cell resolution ST technologies: MERSCOPE/Vizgen, CosMx/Nanostring, and Xenium/10X. Spacia unveiled how endothelial cells, fibroblasts and B cells in the tumor microenvironment contribute to Epithelial-Mesenchymal Transition and lineage plasticity in prostate cancer cells. We deployed spacia in a set of pan-cancer datasets and showed that B cells also participate in PDL1/PD1 signaling in tumors. We demonstrated that a CD8+ T cell/PDL1 effectiveness signature derived from spacia analyses is associated with patient survival and response to immune checkpoint inhibitor treatments in 3,354 patients. We revealed differential spatial interaction patterns between γδ T cells and liver hepatocytes in healthy and cancerous contexts. Overall, spacia represents a notable step in advancing quantitative theories of cellular communications.

Community healthcare appointments as an alternative to emergency department assessment: an exploration of family acceptability and preferences

PURPOSE

Pediatric emergency departments are overcrowded, in part due to many non-emergent visits. We aimed to assess the proportion of parents interested in leaving the pediatric emergency department (ED) prior to physician assessment if they could be offered a scheduled community healthcare appointment. We explored differences in care children received in the ED stratified by interest in a community healthcare appointment and parents' reasons when they were not interested.

METHODS

We conducted a 14-item survey within the pediatric ED at a Canadian tertiary care teaching hospital to assess parents' interest if a program offered community healthcare appointments and we determined preferred appointment characteristics. All parents presenting with children triaged as CTAS 2-5 who met eligibility criteria were approached by a research assistant prior to physician assessment. Surveys were paired with the medical chart outlining the care received. Descriptive statistics and a regression model were used to describe characteristics of families and care received among those who were and were not interested in a community healthcare appointment.

RESULTS

In total, 403 surveys were completed. Overall, 236 participants (58.6%; 95% CI 53.8-63.4) were interested in a community healthcare appointment. In general, parents who were interested in a community healthcare appointment were younger and presented with younger children compared to those who were not interested. Among those interested, there was a preference to have the appointment with a pediatrician or family physician, timely access to an appointment, and appointments scheduled outside of regular business hours.

CONCLUSION

Our study provides evidence that there is interest in an alternative care access model positioned to reduce pediatric ED congestion. We found that parents would be interested in leaving the pediatric ED in favor of a community healthcare appointment, provided it was with a physician and available in a timely manner.

Bony structure enhanced synthetic CT generation using Dixon sequences for pelvis MR-only radiotherapy

BACKGROUND

MRI-only radiotherapy planning (MROP) is beneficial to patients by avoiding MRI/CT registration errors, simplifying the radiation treatment simulation workflow and reducing exposure to ionizing radiation. MRI is the primary imaging modality for soft tissue delineation. Treatment planning CTs (i.e., CT simulation scan) are redundant if a synthetic CT (sCT) can be generated from the MRI to provide the patient positioning and electron density information. Unsupervised deep learning (DL) models like CycleGAN are widely used in MR-to-sCT conversion, when paired patient CT and MR image datasets are not available for model training. However, compared to supervised DL models, they cannot guarantee anatomic consistency, especially around bone.

PURPOSE

The purpose of this work was to improve the sCT accuracy generated from MRI around bone for MROP.

METHODS

To generate more reliable bony structures on sCT images, we proposed to add bony structure constraints in the unsupervised CycleGAN model's loss function and leverage Dixon constructed fat and in-phase (IP) MR images. Dixon images provide better bone contrast than T2-weighted images as inputs to a modified multi-channel CycleGAN. A private dataset with a total of 31 prostate cancer patients were used for training (20) and testing (11).

RESULTS

We compared model performance with and without bony structure constraints using single- and multi-channel inputs. Among all the models, multi-channel CycleGAN with bony structure constraints had the lowest mean absolute error, both inside the bone and whole body (50.7 and 145.2 HU). This approach also resulted in the highest Dice similarity coefficient (0.88) of all bony structures compared with the planning CT.

CONCLUSION

Modified multi-channel CycleGAN with bony structure constraints, taking Dixon-constructed fat and IP images as inputs, can generate clinically suitable sCT images in both bone and soft tissue. The generated sCT images have the potential to be used for accurate dose calculation and patient positioning in MROP radiation therapy.

Prostate Cancer, Version 4.2023, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Prostate Cancer provide a framework on which to base decisions regarding the workup of patients with prostate cancer, risk stratification and management of localized disease, post-treatment monitoring, and treatment of recurrence and advanced disease. The Guidelines sections included in this article focus on the management of metastatic castration-sensitive disease, nonmetastatic castration-resistant prostate cancer (CRPC), and metastatic CRPC (mCRPC). Androgen deprivation therapy (ADT) with treatment intensification is strongly recommended for patients with metastatic castration-sensitive prostate cancer. For patients with nonmetastatic CRPC, ADT is continued with or without the addition of certain secondary hormone therapies depending on prostate-specific antigen doubling time. In the mCRPC setting, ADT is continued with the sequential addition of certain secondary hormone therapies, chemotherapies, immunotherapies, radiopharmaceuticals, and/or targeted therapies. The NCCN Prostate Cancer Panel emphasizes a shared decision-making approach in all disease settings based on patient preferences, prior treatment exposures, the presence or absence of visceral disease, symptoms, and potential side effects.

9 MOG associated encephalitis presenting as idiopathic intracranial hypertension

A young Caucasian male (7y) with normal BMI was atypical for his provisional diagnosis of Idiopathic Intracranial Hypertension (IIH), that resolved following a Lumbar Puncture (LP). At 8y he presented with a 2-week history of headaches and vomiting that started some weeks after flu vaccination and an upper respiratory infection.Visual Acuity (VA) and colour vision were normal. Ocular motility was full. Fundoscopy and OCT showed recurrence of papilloedema, with enlarged blind spots on Kinetic perimetry.LP opening pressure was 30cm H2O and CSF white cells were elevated (23). Repeat brain and spine imaging showed new white matter signal changes in keeping with neuroinflammation, as well as enhancement of the left optic nerve extending to the chiasm and optic tract. VA, colour vision and pupillary reactions remained normal.Pattern VEP peak times were prolonged from the left eye compared to right eye to small check widths, consistent with relative macular-cortex pathway dysfunction. Hemifield PVEPs were slightly prolonged and reduced from the bitemporal fields indicating chiasmal dysfunction. Normal PERGs excluded PVEP delay associated with primary RGC disease.Further investigations showed oligoclonal band and serum-MOG antibody positivity.Management: Initial treatment with Acetazolamide 125mg bd for a week, following LP, was changed to IV methylprednisolone followed by oral prednisolone.Symptoms improved significantly following LP and steroid treatment. He will be followed in a Demyelination Clinic.MOG-associated disease has been reported with raised intracranial pressure and should be considered especially in children with atypical clinical phenotype for IIH.

Organ sparing treatment for penile cancer using a 3D-printed high-dose-rate brachytherapy applicator

PURPOSE

We present a case study of the treatment of localized squamous cell carcinoma on the glans penis with a custom-fabricated high-dose-rate (HDR) brachytherapy applicator.

METHODS AND MATERIALS

A cylindrically shaped applicator was fabricated with eight embedded channels suitable for standard plastic brachytherapy catheters. An additional custom silicone bolus/sleeve was designed to be used with the 3D-printed applicator to provide an additional offset from the source to skin to reduce the surface dose and for patient comfort.

RESULTS

The patient (recurrent cT1a penile cancer) underwent CT simulation, and the brachytherapy plan was created with a nominal prescription dose of 40 Gy in 10 fractions given bidaily to the surface, and 35 Gy at 5 mm depth. Dose coverage to the clinical target volume was 94% (D90). Most fractions were treated with only 5-10 min of setup time. Follow up visits up to 1 year showed no evidence of disease with no significant changes in urinary and sexual function and limited cosmetic detriment to the patient.

CONCLUSIONS

Patient-specific organ-sparing HDR plesiotherapy using 3D printing technology can provide reliable and reproducible patient setup and may be effective in achieving disease control for superficial penile cancer, although preserving patient quality of life.

Cognitive aids in the management of clinical emergencies: a systematic review

Clinical emergencies can be defined as unpredictable events that necessitate immediate intervention. Safety critical industries have acknowledged the difficulties of responding to such crises. Strategies to improve human performance and mitigate its limitations include the provision and use of cognitive aids, a family of tools that includes algorithms, checklists and decision aids. This systematic review evaluates the usefulness of cognitive aids in clinical emergencies. Following a systematic search of the electronic databases, we included 13 randomised controlled trials, reported in 16 publications. Each compared cognitive aids with usual care in the context of an anaesthetic, medical, surgical or trauma emergency involving adults. Most trials used only clinicians in the development and testing of the cognitive aids, and only some trials provided familiarisation with the cognitive aids before they were deployed. The primary outcome was the completeness of care delivered to the patient. Cognitive aids were associated with a reduction in the incidence of missed care steps from 43.3% to 11% (RR (95%CI) 0.29 (0.15-0.16); p < 0.001), and the quality of evidence was rated as moderate. The use of cognitive aids was related to decreases in the incidence of errors, increases in the rate of correctly performed steps and improvement in the clinical teamwork skills scores, non-technical skills scores, subjective conflict resolution scores and the global assessment of team performance. Cognitive aids had an inconsistent influence on the time to first intervention and time to complete care of the patient's condition. It is possible that this was a reflection of how common or rare the crisis in question was as well as the experience and expertise of the clinicians and team. Sufficient thought should be applied to the development of the content and design of cognitive aids, with consideration of the pre-existing guideline ecosystem. Cognitive aids should be tested before their deployment with adequate clinician and team training.

Preliminary Evaluation of PTV Margins for Online Adaptive Radiation Therapy of the Prostatic Fossa

PURPOSE

In modern trials, traditional planning target volume (PTV) margins for postoperative prostate radiation therapy have been large (7-10 mm) to account for both daily changes in patient positioning and target deformation. With daily adaptive radiation therapy, these interfractional changes could be minimized, potentially reducing the margins required for treatment and improving adjacent normal-tissue dosimetry.

METHODS AND MATERIALS

A single-center retrospective study was conducted from March 2021 to November 2021. Patients receiving conventionally fractionated postoperative radiation therapy (PORT) for prostate cancer with pretreatment and posttreatment cone beam computed tomography (CBCT) imaging (pre-CBCT and post-CBCT, respectively) were included (248 paired images). Pretreatment and posttreatment clinical target volumes (pre-CTVs and post-CTVs) were contoured by a single observer on all CBCTs and verified by a second observer. Motion was calculated from pre-CTV to that of the post-CTV, and predicted margins were calculated with van Herk's formula. Adequate coverage of the proposed planning target volume (PTV) margin expansions (pre-PTV) were verified by determining overlap with post-CTV. In a smaller cohort (25 paired images), dosimetric changes with the proposed online adaptive margins were compared with conventional plans in the Ethos emulator environment.

RESULTS

The estimated margins predicted to achieve ≥95% CTV coverage for 90% of the population were 1.6 mm, 2.0 mm, and 2.2 mm (x-, y-, and z -xes, respectively), with 95% of the absolute region of interest displacement being within 1.9 mm, 2.8 mm, and 2.1 mm. After symmetrically expanding all pre-CTVs by 3 mm, the percentage of paired images achieving ≥95% CTV coverage was 97.1%. When comparing adaptive plans (3-mm margins) with scheduled plans (7-mm margins), rectum dosimetry significantly improved, with an average relative reduction in V40Gy[cc] of 59.2% and V65Gy[cc] of 79.5% (where V40Gy and V65Gy are defined as the volumes receiving 40 Gy and 65 Gy or higher dose, respectively).

CONCLUSIONS

Online daily adaptive radiation therapy could significantly decrease PTV margins for prostatic PORT and improve rectal dosimetry, with a symmetrical expansion of 3 mm achieving excellent coverage in this cohort. These results need to be validated in a larger prospective cohort.

NCCN Guidelines® Insights: Prostate Cancer, Version 1.2023

The NCCN Guidelines for Prostate Cancer address staging and risk assessment after a prostate cancer diagnosis and include management options for localized, regional, recurrent, and metastatic disease. The NCCN Prostate Cancer Panel meets annually to reevaluate and update their recommendations based on new clinical data and input from within NCCN Member Institutions and from external entities. These NCCN Guidelines Insights summarizes much of the panel's discussions for the 4.2022 and 1.2023 updates to the guidelines regarding systemic therapy for metastatic prostate cancer.

Association of Preoperative Pulse Pressure and Oxygen Delivery Index During Cardiopulmonary Bypass With Postoperative Acute Kidney Injury

OBJECTIVE

To investigate if oxygen delivery index during cardiopulmonary bypass (DO₂I) was more strongly associated with acute kidney injury (AKI), the higher the patient's preoperative pulse pressure (PP).

DESIGN

Retrospective cohort of 1064 patients undergoing cardiac surgery.

SETTING

Single academic healthcare center.

PARTICIPANTS

Adult patients undergoing coronary artery bypass grafting, valve, aortic, or combined surgery requiring cardiopulmonary bypass.

INTERVENTIONS

Hemoglobin, arterial oxygen saturation, and pump flow recorded no fewer than every 30 min were extracted from the patients' perfusion records, and DO₂I was calculated. The AKI was assessed from the pre- and postoperative creatinine and urine output values using the Acute Kidney Injury Network criteria. The sample was stratified in 5 categories of progressively higher PP. The patient characteristics and intraoperative variables were evaluated in univariate analysis for a relationship with AKI. The significant risk factors from the univariate analysis then were evaluated in a multivariate analysis and assessed for logistic fit with respect to AKI.

PRIMARY OUTCOME

The AKI assessed as a binary outcome.

MEASUREMENTS AND MAIN RESULTS

Age, body surface area, DO₂I, history of heart failure, and baseline creatinine were associated significantly with AKI, as was an interaction term between the PP category and DO₂I (p = 0.0067). The higher the PP category, the stronger the observed association between DO₂I and AKI, and the higher the variability in the predicted risk of AKI dependent on DO₂I.

CONCLUSIONS

A lower DO₂I during cardiopulmonary bypass appeared more strongly associated with a higher likelihood of developing AKI, the higher the patient's preoperative pulse pressure.

First experience of implementing Candida auris real-time PCR for surveillance in the UK: detection of multiple introductions with two international clades and improved patient outcomes

BACKGROUND

Candida auris has been associated with rapid transmission and high mortality. A novel PCR-based surveillance programme was initiated at a London teaching hospital from January 2018. The results of this implementation until March 2019 are presented along with the clinical, transmission and phylogenetic characteristics encountered in that setting.

METHODS

A real-time PCR assay for C. auris was developed, validated, and implemented for direct use on skin swabs and urine. Environmental swabs were also tested by PCR as an emergency outbreak-control measure. Clinical risk factors and outcomes of patients were determined. Environmental dispersal was assessed using 24 h settle plate cultures around nine colonized patients followed by air sampling around one colonized patient during high- and low-turbulence activities. Sequencing was performed using Illumina HiSeq and maximum likelihood phylogenies were constructed using rapid bootstrap analysis.

RESULTS

Twenty-one C. auris colonized patients were identified. Median turnaround time of colonization detection reduced from 141 h (5.8 days) to approximately 24 h enabling rapid infection-control precautions. Settle plates detected 70-600 cfu/m² around colonized patients over 24 h and air sampling suggested dispersal during turbulent activities. C. auris DNA was detected from 35.7% environmental swabs. Despite being in a high-risk setting, no patients developed invasive infection. Sequencing analysis of isolates from this centre identified two introductions of the South Asian (Clade I) and one of the South African (Clade III) strain.

CONCLUSION

The PCR offers a rapid, scalable method of screening and supports clinical risk reduction in settings likely to encounter multiple introductions.

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.

nab-Sirolimus for patients with advanced malignant PEComa with or without prior mTOR inhibitors: Biomarker results from AMPECT and an expanded access program

11574

Background: Malignant perivascular epithelioid cell tumor (PEComa) is a rare and aggressive sarcoma. nab-Sirolimus is an albumin-bound intravenous (IV) mTOR inhibitor (mTORi) approved for the treatment of adult patients with locally advanced unresectable or metastatic malignant PEComa. The AMPECT trial (NCT02494570) was the first prospective study in advanced malignant PEComa. In exploratory biomarker analyses, TSC1 or TSC2 alterations were associated with response. We report data from the final analysis of AMPECT patients, who were naïve to mTORi, and in patients with malignant PEComa with prior mTORi exposure treated with nab-sirolimus in an expanded access program (EAP) (NCT03817515). Methods: In AMPECT, patients with malignant PEComa naïve to mTORi received nab-sirolimus (100 mg/m2 IV days 1 and 8 of every 21-day cycle) until progression or unacceptable toxicity. The primary endpoint was ORR by independent radiology review. Other endpoints included duration of response (DOR) and disease control rate (DCR), defined as complete response (CR), partial response (PR), or stable disease (SD) at ≥12 weeks. In the EAP, patients with malignant PEComa and prior mTORi exposure received the same dose of nab-sirolimus as in AMPECT. Responses and DCR were evaluated post hoc via electronic medical record review. Genetic profiling, including TSC1 or TSC2 status, was assessed in both protocols, but no specific mutation criteria were required for enrollment. Results: Data include 47 total efficacy-evaluable patients, 31 in AMPECT and 16 with malignant PEComa and prior mTORi exposure treated in the EAP from July 2019–July 2021. Prior mTORi on the EAP included sirolimus, everolimus, temsirolimus, or sapanisertib; 12 patients had exposure to 1 prior mTORi and 4 to ≥2 prior mTORi, and 50% had had progressive disease as best response on mTORi. In AMPECT, ORR was 39% (12/31 patients), and DCR was 71%. Median DOR was not reached after 3 years of follow-up. On the EAP, 4/16 patients (25%) achieved PR (DOR range: 1.3+–25.2+ months, 3 ongoing), and 8/16 (50%) had SD as best response; the DCR was 63% (10/16). Of patients with known TSC1 or TSC2 inactivating alterations in the combined datasets (n = 23), 57% had a response (AMPECT, 64%; EAP, 44%). There were no Grade 4 or 5 treatment-related adverse events on either protocol Conclusions: nab-Sirolimus provided durable responses in mTORi-naïve patients with malignant PEComa and clinical benefit in an expanded access protocol for patients with malignant PEComa with prior mTORi therapy. Although AMPECT and the EAP cannot be directly compared, response rates showed similar trends regardless of prior mTORi exposure and in patients with TSC1 or TSC2 alterations. Based on the emerging biomarker results, a tissue-agnostic study in patients with TSC1 and TSC2 alterations has been initiated (NCT05103358). Clinical trial information: NCT02494570, NCT03817515.

Waning Immunity Against Respiratory Syncytial Virus During the Coronavirus Disease 2019 Pandemic

Health jurisdictions have seen a near-disappearance of respiratory syncytial virus (RSV) during the first year of the coronavirus disease 2019 (COVID-19) pandemic. Over this corresponding period, we report a reduction in RSV antibody levels and live virus neutralization in sera from women of childbearing age and infants between May to June 2020 and February to June 2021, in British Columbia (BC), Canada. This supports that antibody immunity against RSV is relatively short-lived and that maintaining optimal antibody levels in infants requires repeated maternal viral exposure. Waning immunity may explain the interseasonal resurgence of RSV cases observed in BC and other countries.

Meningitis following cerebrospinal fluid-cutaneous fistula secondary to combined spinal-epidural anaesthesia for elective caesarean delivery

Cerebrospinal fluid-cutaneous fistula is a rare complication associated with neuraxial procedures. Here, we describe a case of fistula formation related to combined spinal-epidural anaesthesia for elective caesarean delivery, where the epidural catheter was removed only two hours later. The clear fluid leaking persistently from the site of the skin puncture associated with the epidural insertion site was confirmed to be cerebrospinal fluid with an increased beta-trace protein, and the fistula was closed with skin sutures. Subsequently, the patient presented with neurological signs and symptoms consistent with meningitis and she was treated empirically with intravenous antibiotics. Cerebrospinal fluid-cutaneous fistula formation with secondary meningitis is an exceptionally rare event in obstetric anaesthesia.

PSA-Net: Deep learning-based physician style-aware segmentation network for postoperative prostate cancer clinical target volumes

PURPOSE

Automatic segmentation of medical images with deep learning (DL) algorithms has proven highly successful in recent times. With most of these automation networks, inter-observer variation is an acknowledged problem that leads to suboptimal results. This problem is even more significant in segmenting postoperative clinical target volumes (CTV) because they lack a macroscopic visible tumor in the image. This study, using postoperative prostate CTV segmentation as the test case, tries to determine 1) whether physician styles are consistent and learnable, 2) whether physician style affects treatment outcome and toxicity, and 3) how to explicitly deal with different physician styles in DL-assisted CTV segmentation to facilitate its clinical acceptance.

METHODS

A dataset of 373 postoperative prostate cancer patients from UT Southwestern Medical Center was used for this study. We used another 83 patients from Mayo Clinic to validate the developed model and its adaptability. To determine whether physician styles are consistent and learnable, we trained a 3D convolutional neural network classifier to identify which physician had contoured a CTV from just the contour and the corresponding CT scan. Next, we evaluated whether adapting automatic segmentation to specific physician styles would be clinically feasible based on a lack of difference between outcomes. Here, biochemical progression-free survival (BCFS) and grade 3+ genitourinary and gastrointestinal toxicity were estimated with the Kaplan-Meier method and compared between physician styles with the log rank test and subsequently with a multivariate Cox regression. When we found no statistically significant differences in outcome or toxicity between contouring styles, we proposed a concept called physician style-aware (PSA) segmentation by developing an encoder-multidecoder network with perceptual loss to model different physician styles of CTV segmentation.

RESULTS

The classification network captured the different physician styles with 87% accuracy. Subsequent outcome analysis showed no differences in BCFS and grade 3+ toxicity among physicians. With the proposed physician style-aware network (PSA-Net), Dice similarity coefficient (DSC) accuracy for all physicians was 3.4% higher on average than with a general model that does not differentiate physician styles. We show that these stylistic contouring variations also exist between institutions that follow the same segmentation guidelines, and we show the proposed method's effectiveness in adapting to new institutional styles. We observed an accuracy improvement of 5% in terms of DSC when adapting to the style of a separate institution.

CONCLUSION

The performance of the classification network established that physician styles are learnable, and the lack of difference between outcomes among physicians shows that the network can feasibly adapt to different styles in the clinic. Therefore, we developed a novel PSA-Net model that can produce contours specific to the treating physician, thus improving segmentation accuracy and avoiding the need to train multiple models to achieve different style segmentations. We successfully validated this model on data from a separate institution, thus supporting the model's generalizability to diverse datasets.

1602 A Quality Improvement Project on The Management of Patients with Traumatic Head Injury Presenting to A District General Hospital

Introduction

Traumatic Brain Injury (TBI) is associated with morbidity and mortality. All District General Hospitals (DGH) in West Midlands liaise with Neurosurgery centres for management of these patients through a referral system (NORSe). The aim of this study was to assess outcomes in TBI following the implementation of vital interventions.

Method

A retrospective data was collected between 1/1/2019 and 1/12/2020. We included all patients admitted with traumatic brain injury over the age of 16. We accessed the data from the hospital database, clinical notes, and NORSe. A re-audit was performed following implementations of recommendations (proforma and care of elderly input). Further data were collected prospectively.

Results

Our cohort included n1=61 patients (first cycle) and n2= 29 (second cycle). The demographic age and gender were comparable in both cycles. The median time for Neurosurgery advice was 229 minutes (IQR 60-690) in the first cycle as compared to 80 minutes (IQR 40-120, P &lt; 0.05) and the main cause for delay was inadequate information transfer. The mortality rate was 24% (5 were attributed to sepsis), as compared to 14% in the second cycle. The median length of stay (LOS) was 4 days (IQR 3-13.5) in the first cycle, which translates to a cost of £26,815 per quarter. In comparison, LOS was 3 days (IQR 2-4), which translates to the cost of bed occupancy of £12,771 and saving of £14,043 per quarter, in the second cycle.

Conclusions

The introduction of simple interventions in a DGH can help to significantly improve patient outcomes in those admitted with Traumatic brain injury.

Stereotactic Ablative Radiation Therapy for Oligoprogressive Renal Cell Carcinoma

PURPOSE

Oligoprogression, defined as limited sites of progression on systemic therapy, in patients with metastatic renal cell carcinoma (mRCC) is not uncommon, possibly because of inter- and intratumoral heterogeneity. We evaluated the effect of stereotactic ablative radiation therapy (SAbR) for longitudinal control of oligoprogressive mRCC.

METHODS AND MATERIALS

Patients with extracranial mRCC were included in this retrospective analysis if they progressed in ≤3 sites on systemic therapy while demonstrating response/stability at other sites and received SAbR to all progressing sites without switching systemic therapy. Our primary endpoint was modified progression-free survival (mPFS), which we calculated from the start of SAbR to the start of a subsequent systemic therapy, death, or loss to follow-up.

RESULTS

We identified 36 patients with a median follow-up of 20.4 months (interquartile range, 10.9-29.4). Forty-three sites were treated with SAbR with a median dose of 36 Gy (range, 18-50) in 3 fractions (range, 1-5). Median time to SAbR from the start of systemic therapy was 11.4 months (interquartile range, 6.1-17.1). Median mPFS was 9.2 months (95% confidence interval [CI], 5.9-13.2). Patients receiving SAbR while on immunotherapy exhibited a longer median mPFS (>28.4 months, log-rank P = .0001) than patients not on immunotherapy (9.2 months). Median overall survival from SAbR administration was 43.4 months (95% CI, 21.5-not Reached). The 1-year local control rate was 93% (95% CI, 78.7-97.5). Most SAbR-related toxicities were grade 1 to 2 (33% of patients), with one grade 5 hemoptysis event possibly related to SAbR or disease progression.

CONCLUSIONS

SAbR has the potential to extend the the duration of current systemic therapy for selected patients with mRCC, preserving subsequent therapies for later administration possibly enabling longer treatment duration.

P–212 Mitochondrial DNA content shows a significant association with timing of human embryo development and fertility diagnosis in euploid embryos

Study question

Does mitochondrial DNA content (mtDNA) correlate with clinical parameters and embryo morphokinetics using advanced time-lapse technology?

Summary answer

mtDNA correlated with embryo morphokinetics and the growth trajectory of euploid embryos. Maternal age, anti-mullerian hormone level and fertility diagnosis were significantly associated with mtDNA.

What is known already

With the push towards single embryo transfers, laboratories are working to improve embryo selection. In addition to conventional microscopy, preimplantation genetic testing and time-lapse microscopy have been utilized to aid in embryo selection. More recently, as mtDNA may represent the energy potential of an embryo, some data have supported the use of mtDNA as an additional tool. Limited studies have suggested that a lower amount of mtDNA is associated with higher rates of implantation and improved embryo quality.

Study design, size, duration

This is a retrospective chart review. All embryos that underwent preimplantation genetic testing for aneuploidy (PGT-A) between January to December of 2020 were studied.

Participants/materials, setting, methods

Women undergoing in vitro fertilization (IVF) with intracytoplasmic sperm injection undergoing PGT-A were studied. All patients were from a single academic institution. This study exclusively examined the characteristics of euploid embryos. Mitochondrial DNA content was expressed as a ratio of mtDNA:nDNA (MitoScore). Time-lapse imaging was utilized to evaluate embryo development every 15 minutes in 5–7 focal planes. Chi square test and Spearman correlation analysis were performed with a p-value of &lt; 0.05 considered significant.

Main results and the role of chance

A total of 494 embryos from 52 women who underwent 58 IVF cycles were cultured to blastocyst and 331 embryos were biopsied for PGT-A evaluation. Of these, 132 embryos were diagnosed as euploid. A moderate positive correlation was found between MitoScore and time to morula, time to blast and time to expanded blast (correlation value 0.54, 0.50 and 0.54, respectively; p &lt; 0.001). Consistent with this trend, day 5 blastocysts had a significantly lower MitoScore values than day 6 blastocysts (20.2 v. 29.2; p &lt; 0.001). When examining all biopsied euploid embryos, no significant association was found between MitoScore, blastocyst maturity, trophectoderm or inner cell mass scores.

Our data also demonstrated a positive correlation between MitoScore and maternal age (correlation factor 0.33; p &lt; 0.001). A negative association between MitoScore and serum anti-mullerian hormone levels (correlation factor –0.20; p &lt; 0.021) was also noted. Of particular interest was the significant association between fertility diagnosis and mitochondrial score (p &lt; 0.001).

Even amongst euploid embryos, mtDNA content varied widely, potentially reflecting differences in embryo potential and quality. Additionally, the significant difference in MitoScore between that day 5 and day 6 blastocysts may reflect a fundamental difference in cytoplasmic characteristics and requires further study.

Limitations, reasons for caution

Due to the study cohort of euploid embryos undergoing PGT-A, this study was biased for the selection of high grade embryos. This limited diversity in embryo quality may have masked other potential associations between mitochondrial content and blastocyst quality.

Wider implications of the findings: mtDNA may be additional tool aiding in embryo selection as IVF labs work to improve pregnancy rates while minimizing the risks of transferring multiple embryos. To our knowledge, this is the largest study assessing the relationship of mtDNA content of blastocysts and the timing of embryo development using time-lapse imaging.

Trial registration number

None

Effect of the COVID-19 Pandemic on Patient Volumes, Acuity, and Outcomes in Pediatric Emergency Departments: A Nationwide Study

OBJECTIVES

The aim of this study was to quantify the effect of the COVID-19 pandemic on pediatric emergency department (ED) utilization and outcomes.

METHODS

This study is an interrupted-time-series observational study of children presenting to 11 Canadian tertiary-care pediatric EDs. Data were grouped into weeks in 3 study periods: prepandemic (January 1, 2018-January 27, 2020), peripandemic (January 28, 2020-March 10, 2020), and early pandemic (March 11, 2020-April 30, 2020). These periods were compared with the same time intervals in the 2 preceding calendar years. Primary outcomes were number of ED visits per week. The secondary outcomes were triage acuity, hospitalization, intensive care unit (ICU) admission, mortality, length of hospital stay, ED revisits, and visits for trauma and mental health concerns.

RESULTS

There were 577,807 ED visits (median age, 4.5 years; 52.9% male). Relative to the prepandemic period, there was a reduction [-58%; 95% confidence interval (CI), -63% to -51%] in the number of ED visits during the early-pandemic period, with concomitant higher acuity. There was a concurrent increase in the proportion of ward [odds ratio (OR), 1.39; 95% CI, 1.32-1.45] and intensive care unit (OR, 1.20; 95% CI, 1.01-1.42) admissions, and trauma-related ED visits among children less than 10 years (OR, 1.51; 95% CI, 1.45-1.56). Mental health-related visits in children declined in the early-pandemic period (in <10 years, -60%; 95% CI, -67% to -51%; in children ≥10 years: -56%; 95% CI, -63% to -47%) relative to the pre-COVID-19 period. There were no differences in mortality or length of stay; however, ED revisits within 72 hours were reduced during the early-pandemic period (percent change: -55%; 95% CI, -61% to -49%; P < 0.001).

CONCLUSIONS

After the declaration of the COVID-19 pandemic, dramatic reductions in pediatric ED visits occurred across Canada. Children seeking ED care were sicker, and there was an increase in trauma-related visits among children more than 10 years of age, whereas mental health visits declined during the early-pandemic period. When faced with a future pandemic, public health officials must consider the impact of the illness and the measures implemented on children's health and acute care needs.

Effect of Repetitive Simulation Training on Emergency Medical Services Team Performance in Simulated Pediatric Medical Emergencies

OBJECTIVE

Emergency medical services (EMS) professionals infrequently transport children leading to difficulty in recognition and management of pediatric critical illness. Simulation provides an opportunity to train EMS professionals on pediatric emergencies. The objective of this study was to examine the effect of serial simulation training over 6 months on EMS psychomotor and cognitive performance during team-based care.

METHODS

This was a longitudinal prospective study of a simulation curriculum enrolling EMS professionals over a 6-month period during which they performed three high-fidelity simulations at 3-month intervals. The simulation scenarios included a 15-month-old seizure (T₀), 1-month-old with hypoglycemia (T₁), and 4-year-old clonidine ingestion (T₂). All scenarios were standardized and required recognition and management of respiratory failure and decompensated shock. Scenarios were videotaped and two investigators scored EMS team interventions during simulations using a standardized scoring tool. Inter-rater reliability was assessed on 30% of videos using kappa analysis. Volumes of administered intravenous fluid (IVF) and medications were measured to assess for errors in administration. The primary outcome was the change in scenario score from T₀ to T₂.

RESULTS

A total of 135 team-based simulations were conducted over the study period (48, 40, and 47 at T₀, T₁, and T₂, respectively). Inter-rater reliability between reviewers was very good (κ = 0.7). Median simulation score improved from T₀ to T₂ (24 vs 31, p < 0.001, maximum score possible = 42). The proportion of completed tasks increased across multiple categories including improved recognition of respiratory decompensation (19% vs. 56%), management of the pediatric airway (44% vs. 88%), and timeliness of vascular access (10% vs. 38%). Correct IVF administration varied by scenario (25% vs. 52% vs. 30%, p = 0.02).

CONCLUSION

Serial simulation improved EMS team-based care in both recognition and management of pediatric emergencies. A standardized pediatric simulation curriculum can be used to train EMS professionals on pediatric emergencies and improve performance.

Metastasis-directed radiation therapy after radical cystectomy for bladder cancer

PURPOSE

Metastasis-directed radiation therapy (MDRT) may improve oncologic and quality of life outcomes in patients with metastatic cancer, but data on its use in metastatic bladder cancer is severely limited. We sought to review our institutional experience with MDRT in patients with metastatic bladder cancer following radical cystectomy.

MATERIALS AND METHODS

We reviewed records of patients who underwent radical cystectomy and subsequent MDRT at our institution between 2009 and 2020. Baseline demographic and clinical/pathologic factors were collected, as were details of treatment including systemic therapy and MDRT. Cases were categorized by treatment intent as consolidative (intended to prolong survival) and palliative (intended only to relieve symptoms). Response to treatment, survival, and toxicity outcomes were reviewed.

RESULTS

A total of 52 patients underwent MDRT following radical cystectomy. MDRT was categorized as consolidative in 40% of cases and palliative in 60%. Toxicity (CTCAE Grade ≥ 2) was reported in 15% of patients, none of which exceeded Grade 3. Most patients undergoing consolidative MDRT were treated with SBRT techniques (76%) and a majority (67%) received concurrent treatment with an immuno-oncology agent. Among patients treated with consolidative intent, 2-year progression-free and overall survival were 19% and 60%, respectively.

CONCLUSION

MDRT is safe and well-tolerated by a majority of patients. A majority of patients treated with consolidative intent survived ≥ 2 years from treatment.

The scope of hospital medicine practice at night: a national survey of night shift hospitalists

Introduction: Although in-person hospitalist presence, increasingly staffed by dedicated nocturnists, has become the norm overnight in the hospital, the scope of nocturnist practice and typical workload has not been defined. This study examines the clinical responsibilities and patient safety perceptions of hospitalists who work night shifts in the United States.Methods: In the fall of 2019, a cross-sectional, web-based survey was administered to physician and nurse practitioner/physician assistant (NP/PA) hospitalists who work night shifts. The questionnaire assessed night staffing structure, typical responsibilities, patient volume, perceptions of safety overnight, as well as demographic information. The survey was posted on the Society of Hospital Medicine (SHM) Hospital Medicine Exchange (HMX) Online Discussion Forum. Additionally, the survey was distributed by 'snowball method' by respondents to other night hospitalists. Responses were collected anonymously.Results: Of the 167 respondents, 157 reported working night shifts. There was at least one respondent from 32 different states. In addition to performing admissions to medicine services and covering inpatients, night hospitalists cover ICU patients, participate in RRT/Code teams and procedure teams, perform consults, participate in medical education, and take outpatient calls. Across institutions, there was a large distribution in numbers of patients covered in a night shift; however, patient volume fell into typical ranges: 5-10 admissions for physicians, 0-6 admissions for NP/PAs, and 25-75 patient cross-coverage census. When physicians perform more than five admissions per night, hospitalists were less likely to agree that they could provide safe care (88% vs. 63%, p = 0.0006).Conclusions: This is the first national study to examine the clinical responsibilities of hospitalists working overnight. Overnight responsibilities are heterogeneous across institutions. As hospitals are increasingly employing nocturnists, more research is needed to guide night staffing and optimize patient safety.

A deep learning-based framework for segmenting invisible clinical target volumes with estimated uncertainties for post-operative prostate cancer radiotherapy

In post-operative radiotherapy for prostate cancer, precisely contouring the clinical target volume (CTV) to be irradiated is challenging, because the cancerous prostate gland has been surgically removed, so the CTV encompasses the microscopic spread of tumor cells, which cannot be visualized in clinical images like computed tomography or magnetic resonance imaging. In current clinical practice, physicians' segment CTVs manually based on their relationship with nearby organs and other clinical information, but this allows large inter-physician variability. Automating post-operative prostate CTV segmentation with traditional image segmentation methods has yielded suboptimal results. We propose using deep learning to accurately segment post-operative prostate CTVs. The model proposed is trained using labels that were clinically approved and used for patient treatment. To segment the CTV, we segment nearby organs first, then use their relationship with the CTV to assist CTV segmentation. To ease the encoding of distance-based features, which are important for learning both the CTV contours' overlap with the surrounding OARs and the distance from their borders, we add distance prediction as an auxiliary task to the CTV network. To make the DL model practical for clinical use, we use Monte Carlo dropout (MCDO) to estimate model uncertainty. Using MCDO, we estimate and visualize the 95% upper and lower confidence bounds for each prediction which informs the physicians of areas that might require correction. The model proposed achieves an average Dice similarity coefficient (DSC) of 0.87 on a holdout test dataset, much better than established methods, such as atlas-based methods (DSC<0.7). The predicted contours agree with physician contours better than medical resident contours do. A reader study showed that the clinical acceptability of the automatically segmented CTV contours is equal to that of approved clinical contours manually drawn by physicians. Our deep learning model can accurately segment CTVs with the help of surrounding organ masks. Because the DL framework can outperform residents, it can be implemented practically in a clinical workflow to generate initial CTV contours or to guide residents in generating these contours for physicians to review and revise. Providing physicians with the 95% confidence bounds could streamline the review process for an efficient clinical workflow as this would enable physicians to concentrate their inspecting and editing efforts on the large uncertain areas.

822 Lessons Learnt During the COVID-19 Pandemic on Emergency Surgical Admissions in A District General Hospital

Introduction

Coronavirus disease (COVID-19) is an acute severe respiratory distress syndrome which resulted in an unprecedented impact on NHS service provision. We aimed to assess the impact of COVID-19 on general surgical services in a district general hospital.

Method

Electronic health care record data was retrospectively collected from 6th of April to 6th of May for both 2019 and 2020.

Results

Despite fewer referrals and admissions in 2020 (133 vs 177 admissions in 2019), there were more failed discharges (29 vs 17 in 2019) and higher associated costs. Higher numbers of biliary related pathologies and pancreatitis (50 in 2020 vs 25 in 2019), and fewer complaints of non-specific abdominal pain (10 in 2020 vs 22 in 2019) were observed. The use of outpatient investigations decreased by approximately 40% in 2020; however, utilisation of inpatient investigations was comparable.

Conclusions

Better utilisation of outpatient investigations and virtual clinic services may surmount pressures from further peaks of COVID-19. The increase in biliary related cases and pancreatitis may be consequent upon lifestyle changes during lockdown. This merits further investigation and if appropriate, public health intervention. In the absence of an efficacious vaccine, further research would be essential to streamline general surgical services based on clinical risk stratification.

Combined immune checkpoint blockade and radiotherapy induces durable remission in relapsed natural killer/T-cell lymphoma: a case report and review of the literature

BACKGROUND

Extranodal natural killer/T-cell lymphoma is a rare, aggressive non-Hodgkin lymphoma that is treated upfront mostly with L-asparaginase containing regimens. Relapsed extranodal natural killer/T-cell lymphoma is associated with a poor prognosis, and there is no established standard of care.

CASE PRESENTATION

We report the case of a 72 year-old white male with a distant extranasal relapse of extranodal natural killer/T-cell lymphoma that has been managed successfully with a combination of radiation and immune checkpoint blockade with pembrolizumab. Pseudoprogression with new skin and bone lesions on positron emission tomography imaging was encountered during this Caucasian patient's immunotherapy and was successfully managed with supportive care and continuation of immune checkpoint blockade.

CONCLUSIONS

The patient has been in complete clinical, radiologic, and molecular remission for close to 3 years and has not had any immune-related adverse effects. Pseudoprogression is a clinical challenge that can be encountered while patients are treated with immunotherapy, and astute clinical acumen is needed for accurate management. We believe this is the longest duration of response to immune checkpoint blockade in relapsed extranodal natural killer/T-cell lymphoma reported to date in literature. There is a strong biologic rationale in combining radiation with immunotherapy. The optimal timing, dose, and duration of radiation combined with immunotherapy in extranodal natural killer/T-cell lymphoma need to be prospectively evaluated.

A multi-institutional phase I/II trial of focal salvage high-dose-rate brachytherapy for locally recurrent prostate cancer in patients treated with prior radiotherapy (F-SHARP)

TPS265

Background: Approximately 20% of patients with localized prostate cancer who undergo curative-intent radiotherapy develop a clinical recurrence after radiation. Half of these clinical recurrences are a local radio-recurrence (LRR). Patients with LRR have multiple potential salvage local therapy options, but there are limited data guiding management. Prospective clinical trials demonstrate 5-year freedom from biochemical recurrence of ~50-70% with salvage brachytherapy using primarily whole-gland low dose rate or high dose rate (HDR) brachytherapy. However, the risk of severe grade ≥3 late toxicity is 5-15% in prior series, suggesting an opportunity to improve the therapeutic ratio. The F-SHARP trial was designed to study focal salvage HDR brachytherapy as a means to treat LRR after definitive radiotherapy and reduce the toxicity of re-irradiation. Methods: F-SHARP is a two-staged non-randomized phase I/II trial of focal salvage HDR brachytherapy for LRR prostate cancer. The study originated at a single center but will be opening at 3 other institutions in late 2020. Eligibility criteria include biopsy-proven local recurrence after curative radiation therapy (any form) for cT1-T3a N0 M0 prostate adenocarcinoma, no radiographic evidence of nodal or metastatic disease prior to enrollment on CT/MRI and bone scan (fluciclovine PET/CT encouraged), current IPSS ≤20, and no grade ≥3 CTCAE v 4.03 toxicity from prior RT. Initially, study HDR was delivered as a single fraction of up to 30 Gy to the target volume (gross recurrent tumor + 5 mm), with priority given to normal tissue constraints. Based on data in the definitive HDR brachytherapy setting suggesting inferior outcomes with single fraction HDR, a 2 fraction regimen (again delivering up to 30 Gy to the gross recurrent tumor + 5 mm) was added as an option as well. The primary endpoint is Grade ≥3 CTCAE V4.03 RT-related toxicity at 3 months. Assuming that the true toxicity rate in the population is 10% or less, the study has 81% power to reject the null hypothesis that the toxicity rate is 33% or higher. In the first stage, 7 patients will be accrued. If there are 2 or more toxic responses in these 7 patients, the study will be stopped for safety reasons. Otherwise, 17 additional patients will be accrued for a total of 24 patients to evaluate the primary endpoint. After completion of the 24 patient toxicity assessment, the cohort expands to 50 subjects to study freedom from biochemical recurrence (secondary endpoint). Other secondary endpoints include local control, freedom-from local failure, freedom from elsewhere-prostate control, freedom from distant metastasis, freedom from hormonal therapy, disease-free survival, cause-specific survival, and overall survival. The study has completed the initial 24 patient toxicity assessment and continues accrual in the expansion cohort. Clinical trial information: NCT03312972.

NCCN Guidelines Insights: Prostate Cancer, Version 1.2021

The NCCN Guidelines for Prostate Cancer address staging and risk assessment after a prostate cancer diagnosis and include management options for localized, regional, and metastatic disease. Recommendations for disease monitoring and treatment of recurrent disease are also included. The NCCN Prostate Cancer Panel meets annually to reevaluate and update their recommendations based on new clinical data and input from within NCCN Member Institutions and from external entities. This article summarizes the panel’s discussions for the 2021 update of the guidelines with regard to systemic therapy for metastatic castration-resistant prostate cancer.

Local anaesthetic adjuncts for peripheral regional anaesthesia: a narrative review

Moderate-to-severe postoperative pain persists for longer than the duration of single-shot peripheral nerve blocks and hence continues to be a problem even with the routine use of regional anaesthesia techniques. The administration of local anaesthetic adjuncts, defined as the concomitant intravenous or perineural injection of one or more pharmacological agents, is an attractive and technically simple strategy to potentially extend the benefits of peripheral nerve blockade beyond the conventional maximum of 8-14 hours. Historical local anaesthetic adjuncts include perineural adrenaline that has been demonstrated to increase the mean duration of analgesia by as little as just over 1 hour. Of the novel local anaesthetic adjuncts, dexmedetomidine and dexamethasone have best demonstrated the capacity to considerably improve the duration of blocks. Perineural dexmedetomidine and dexamethasone increase the mean duration of analgesia by up to 6 hour and 8 hour, respectively, when combined with long-acting local anaesthetics. The evidence for the safety of these local anaesthetic adjuncts continues to accumulate, although the findings of a neurotoxic effect with perineural dexmedetomidine during in-vitro studies are conflicting. Neither perineural dexmedetomidine nor dexamethasone fulfils all the criteria of the ideal local anaesthetic adjunct. Dexmedetomidine is limited by side-effects such as bradycardia, hypotension and sedation, and dexamethasone slightly increases glycaemia. In view of the concerns related to localised nerve and muscle injury and the lack of consistent evidence for the superiority of the perineural vs. systemic route of administration, we recommend the off-label use of systemic dexamethasone as a local anaesthetic adjunct in a dose of 0.1-0.2 mg.kg^-1 for all patients undergoing surgery associated with significant postoperative pain.

Predicting Hemolytic Uremic Syndrome and Renal Replacement Therapy in Shiga Toxin-producing Escherichia coli-infected Children

BACKGROUND

Shiga toxin-producing Escherichia coli (STEC) infections are leading causes of pediatric acute renal failure. Identifying hemolytic uremic syndrome (HUS) risk factors is needed to guide care.

METHODS

We conducted a multicenter, historical cohort study to identify features associated with development of HUS (primary outcome) and need for renal replacement therapy (RRT) (secondary outcome) in STEC-infected children without HUS at initial presentation. Children aged <18 years who submitted STEC-positive specimens between January 2011 and December 2015 at a participating study institution were eligible.

RESULTS

Of 927 STEC-infected children, 41 (4.4%) had HUS at presentation; of the remaining 886, 126 (14.2%) developed HUS. Predictors (all shown as odds ratio [OR] with 95% confidence interval [CI]) of HUS included younger age (0.77 [.69-.85] per year), leukocyte count ≥13.0 × 103/μL (2.54 [1.42-4.54]), higher hematocrit (1.83 [1.21-2.77] per 5% increase) and serum creatinine (10.82 [1.49-78.69] per 1 mg/dL increase), platelet count <250 × 103/μL (1.92 [1.02-3.60]), lower serum sodium (1.12 [1.02-1.23 per 1 mmol/L decrease), and intravenous fluid administration initiated ≥4 days following diarrhea onset (2.50 [1.14-5.46]). A longer interval from diarrhea onset to index visit was associated with reduced HUS risk (OR, 0.70 [95% CI, .54-.90]). RRT predictors (all shown as OR [95% CI]) included female sex (2.27 [1.14-4.50]), younger age (0.83 [.74-.92] per year), lower serum sodium (1.15 [1.04-1.27] per mmol/L decrease), higher leukocyte count ≥13.0 × 103/μL (2.35 [1.17-4.72]) and creatinine (7.75 [1.20-50.16] per 1 mg/dL increase) concentrations, and initial intravenous fluid administration ≥4 days following diarrhea onset (2.71 [1.18-6.21]).

CONCLUSIONS

The complex nature of STEC infection renders predicting its course a challenge. Risk factors we identified highlight the importance of avoiding dehydration and performing close clinical and laboratory monitoring.

Incidence and outcomes of healthcare-associated COVID-19 infections: significance of delayed diagnosis and correlation with staff absence

BACKGROUND

The sudden increase in COVID-19 admissions in hospitals during the SARS-CoV-2 pandemic of 2020 led to onward transmissions among vulnerable inpatients.

AIMS

This study was performed to evaluate the prevalence and clinical outcomes of healthcare-associated COVID-19 infections (HA-COVID-19) during the 2020 epidemic and study factors which may promote or correlate with its incidence and transmission in a Teaching Hospital NHS Trust in London, UK.

METHODS

Electronic laboratory, patient and staff self-reported sickness records were interrogated from 1st March to 18th April 2020. HA-COVID-19 was defined as COVID-19 with symptom onset within >14 days of admission. Test performance of a single combined throat and nose swab (CTNS) for patient placement was calculated. The effect of delayed RNA positivity (DRP, defined as >48 h delay), staff self-reported COVID-19 sickness absence, hospital bed occupancy, and community incidence of COVID-19 was compared for HA-COVID-19. The incidence of other significant hospital-acquired bacterial infections (HAB) was compared with previous years.

RESULTS

Fifty-eight HA-COVID-19 (7.1%) cases were identified. When compared with community-acquired admitted cases (CA-COVID-19), significant differences were observed in age (P=0.018), ethnicity (P<0.001) and comorbidity burden (P<0.001) but not in 30-day mortality. CTNS-negative predictive value was 60.3%. DRP was associated with greater mortality (P=0.034) and incidence of HA-COVID-19 correlated positively with DRP (R = 0.7108) and staff sickness absence (R = 0.7815). For the study period HAB rates were similar to the previous 2 years.

CONCLUSIONS

Early diagnosis and isolation of COVID-19 patients would help to reduce transmission. A single CTNS has limited value in segregating patients into positive and negative pathways.

Mortality and readmission in non-ischemic compared with ischemic cardiomyopathies after implantable cardioverter-defibrillator implantation

Background/Introduction

Uncertainty remains regarding the benefit of primary prevention ICDs overall in contemporary practice, and particularly in those with NICM compared with ICM.

Purpose

To evaluate the contemporary risk of death and readmission following following implantable cardioverter-defibrillator (ICD) implantation in patients with non-ischemic cardiomyopathies (NICM) compared with ischemic cardiomyopathies (ICM) in a large nationally representative cohort in the United States.

Methods

We used data from the American College of Cardiology (ACC) National Cardiovascular Data Registry (NCDR) ICD Registry linked with Medicare claims from April 1, 2010 to December 31, 2013 to establish a cohort of NICM and ICM patients with a left ventricular ejection fraction ≤35% who received a de novo, primary prevention ICD. We compared mortality, all-cause readmission, and heart failure readmission using Kaplan-Meier curves and Cox proportional hazard regressions models. We also evaluated temporal trends in mortality.

Results

Among 31,044 NICM and 68,458 ICM patients with a median follow up of 2.4 years, one-year mortality was significantly higher in ICM patients (12.3%) compared with NICM (7.9%, p&lt;0.001). The higher mortality in ICM patients remained significant after adjustment for covariates (hazard ratio (HR) 1.40; 95% confidence interval (CI) 1.36 to 1.45), and was consistent in subgroup analyses. These findings were consistent across the duration of the study. ICM patients were also significantly more likely to be readmitted for all causes (adjusted HR 1.15, CI 1.12 to 1.18) and for heart failure (adjusted HR 1.25, CI 1.21 to 1.31).

Conclusions

The risks of mortality and hospital readmission after primary prevention ICD implantation were significantly higher in patients with ICM compared with NICM, and these findings were consistent across all patient subgroups tested and over the duration of the study.

Funding Acknowledgement

Type of funding source: None

Conventional landmark palpation vs. preprocedural ultrasound for neuraxial analgesia and anaesthesia in obstetrics - a systematic review and meta-analysis with trial sequential analyses

The aim of this systematic review and meta-analysis was to examine the efficacy, time taken and the safety of neuraxial blockade performed for obstetric patients with the assistance of preprocedural ultrasound, in comparison with the landmark palpation method. The bibliographic databases Central, CINAHL, EMBASE, Global Health, MEDLINE, Scopus and Web of Science were searched from inception to 13 February 2020 for randomised controlled trials that included pregnant women having neuraxial procedures with preprocedural ultrasound as the intervention and conventional landmark palpation as the comparator. For continuous and dichotomous outcomes, respectively, we calculated the mean difference using the inverse-variance method and the risk ratio with the Mantel-Haenszel method. In all, 22 trials with 2462 patients were included. Confirmed by trial sequential analysis, preprocedural ultrasound increased the first-pass success rate by a risk ratio (95%CI) of 1.46 (1.16-1.82), p = 0.001 in 13 trials with 1253 patients. No evidence of a difference was found in the total time taken between preprocedural ultrasound and landmark palpation, with a mean difference (95%CI) of 50.1 (-13.7 to 113.94) s, p = 0.12 in eight trials with 709 patients. The quality of evidence was graded as low and very low, respectively, for these co-primary outcomes. Sub-group analysis underlined the increased benefit of preprocedural ultrasound for those in whom the neuraxial procedure was predicted to be difficult. Complications, including postpartum back pain and headache, were decreased with preprocedural ultrasound. The adoption of preprocedural ultrasound for neuraxial procedures in obstetrics is recommended and, in the opinion of the authors, should be considered as a standard of care, in view of its potential to increase efficacy and reduce complications without significant prolongation of the total time required.

Addressing a national crisis: the spine hospital and department's response to the COVID-19 pandemic in New York City

In a very brief period, the COVID-19 pandemic has swept across the planet leaving governments, societies, and healthcare systems unprepared and under-resourced. New York City now represents the global viral epicenter with roughly one-third of all mortalities in the United States. To date, our hospital has treated thousands of COVID-19 positive patients and sits at the forefront of the United States response to this pandemic. The goal of this paper is to share the lessons learned by our spine division during a crisis when hospital resources and personnel are stretched thin. Such experiences include management of elective and emergent cases, outpatient clinics, physician redeployment, and general health and wellness. As peak infections spread across the United States, we hope this article will serve as a resource for other spine departments on how to manage patient care and healthcare worker deployment during the COVID-19 crisis.

Abstract 1826: CRISPR mediated KRAS mutant gene editing in pancreatic and colorectal cancer therapy

Background: KRASG12V and KRASG12D mutations are among the most commonly observed mutations in pancreatic (30% and 51%) and colorectal (27% and 45%) adenocarcinomas and have been associated with poor prognosis. Activating mutations in KRAS play potent roles in cancer initiation, propagation, and maintenance. Although they represent important therapeutic targets, no effective treatment for direct inhibition of KRASG12V and KRASG12D mutants have been reported. We have developed a new potent strategy combing the potency of CRISPR for gene editing with a tumor selective nanocarrier, to impair cancer cell proliferation by directly targeting G12V and G12D mutations of the KRAS oncogene.

Methods: ADGN-technology is based on short amphipathic peptides that form stable neutral nanoparticles with CRISPR/Cas9. ADGN nanoparticles containing Cas9mRNA and gRNA targeting either KRASG12D or KRASG12V were evaluated on pancreas (PANC1, PK-45H) and colorectal (LS513, SW480, SW403) cancer cells harboring KRASG12D or KRASG12V mutations. KRAS mutant indel frequency was evaluated by T7E1 method and compared to KRASWT (HT29, HS-69) cells. Cell proliferation was determined by flow cytometry. In-vivo efficacy of IV-administered ADGN/mRNACas9/gRNA complexes was evaluated in PANC1-LUC (KRASG12D) and SW403 (KRASG12V) mouse xenografts. The phosphorylation of ERK and AKT was measured by western blot, KRAS mutation level in the tumor and variation of housekeeping genes were estimated by deep sequencing.

Results: We have developed highly specific gRNAs targeting KRASG12V and KRASG12D mutants complexed with ADGN-nanoparticles. These complexes efficiently and selectively silenced KRASG12V and KRASG12D in colorectal and pancreatic cancer cells in vitro and in vivo. Silencing KRAS mutations reduced the cell proliferation by 70% and the phosphorylation of the downstream effector pathways ERK and AKT. ADGN-nanoparticles containing CRISPR/gRNA targeting KRASG12D abolished PANC1 tumor growth and induced KRASG12D gene editing in the tumor with an indel frequency of 76%. ADGN-nanoparticles containing CRISPR/gRNA targeting KRASG12V abolished SW403 tumor growth and induced KRASG12V gene editing in the tumor with an indel frequency of 82%. In contrast, no effect on tumor growth were observed with ADGN-nanoparticles containing non-specific gRNA or gRNA targeting other KRAS mutations. ADGN/mRNACas9/gRNA targeting KRASG12D or KRASG12V abolished pancreatic and colorectal tumor growth respectively in vivo, without inducing any significant toxicity, emergence of off target effects or other KRAS mutations.

Conclusions: ADGN-nanoparticle containing mRNACas9/gRNA targeting KRASG12D or KRASG12V were effective in selectively targeting mutated KRAS both in vitro and in vivo. Our study provides a proof-of-concept that ADGN/CRISPR can be applied to target driver mutations of cancers in vivo and permanently disrupt the oncogenic alleles, leading to inhibition of tumor growth. We proposed a new strategy for targeting KRAS oncogenes that can be useful in treatment of pancreatic and colorectal cancers.

Citation Format: Gilles Divita, Elodie Czuba, Melanie Guidetti, Audrey Gunenberger, Leslie Tempremant, Veronique Josserand, Neil Desai. CRISPR mediated KRAS mutant gene editing in pancreatic and colorectal cancer therapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1826.

Neuroimaging Appearance of Cerebral Malignant Epithelioid Glioneuronal Tumors in Children

Malignant epithelioid glioneuronal tumor is a rare high-grade, aggressive brain tumor that shows both glial and neuronal differentiation on histopathology but is not included in the current World Health Organization classification. The neuroimaging appearance is variable but may be secondary to the size of the mass and/or location of the tumor. In our series, all epithelioid glioneuronal tumors were encountered in the supratentorial space and included pineal, temporal, and extratemporal lobar cerebral hemisphere locations. When large, the tumors demonstrate cystic degeneration and necrosis, hemorrhage, contrast enhancement, and regions of low apparent diffusion coefficient scalars consistent with patterns seen with other high-grade pediatric brain tumors. The tumors also have a propensity to spread into the meninges at presentation and for distant CSF spread on follow-up imaging.

Quadratus lumborum block vs. transversus abdominis plane block for caesarean delivery: a systematic review and network meta-analysis. Anaesthesia 2020;76:393-403. [PMID: 32621529 DOI: 10.1111/anae.15160]

Caesarean delivery is the most commonly performed inpatient surgical procedure globally. Pain after caesarean delivery is moderate to severe if not adequately treated, and is a primary anaesthetic concern for patients. Transversus abdominis plane and quadratus lumborum blocks are fascial plane blocks that have the potential to improve analgesia following caesarean delivery. Although proponents of the quadratus lumborum block suggest that this technique may provide better analgesia compared with transversus abdominis plane block, there are limited data directly comparing these two techniques. We, therefore, performed a systematic review and network meta-analysis to compare transversus abdominis plane and quadratus lumborum block approaches, seeking randomised controlled trials comparing both techniques to each other, or to control, with or without intrathecal morphine. In all, 31 trials with 2188 patients were included and our primary outcome, the cumulative intravenous morphine equivalent consumption at 24 h, was reported in 12 trials. In the absence of intrathecal morphine, transversus abdominis plane and quadratus lumborum blocks were equivalent, and both were superior to control (moderate-quality evidence). In the presence of intrathecal morphine, no differences were found between control, transversus abdominis plane and quadratus lumborum blocks (moderate-quality evidence). Similar results were found for resting and active pain scores at 4-6 h, 8-12 h, 24 h and 36 h, although quadratus lumborum block was associated with lower pain scores at 36 h when compared with transversus abdominis plane block (very low-quality evidence). However, transversus abdominis plane block was associated with a reduced incidence of postoperative nausea and vomiting (moderate-quality evidence) and sedation when compared with inactive control following intrathecal morphine administration (low-quality evidence). There are insufficient data to draw definitive conclusions, but transversus abdominis plane and quadratus lumborum block appear to be superior to control in the absence of intrathecal morphine, but provide limited additional benefit over inactive control when intrathecal morphine is also used.