A simple ex vivo model of human renal allograft preservation using the gonadal vein

INTRODUCTION

Hypothermic machine perfusion, an organ preservation modality, involves flow of chilled preservation fluid through an allograft's vasculature. This study describes a simple, reproducible, human model that allows for interrogation of flow effects during ex vivo organ perfusion.

MATERIALS AND METHODS

Gonadal veins from deceased human renal allografts were subjected to either static cold storage or hypothermic machine perfusion for up to 24 hours. Caspase-3, Krüppel-like factor 2 expression and electron microscopic analysis were compared between 'flow' and 'no-flow' conditions, with living donor gonadal vein sections serving as negative controls.

RESULTS

The increase in caspase-3 expression was less pronounced for hypothermic machine-perfused veins compared with static cold storage (median-fold increase 1.2 vs 2.3; P < 0.05). Transmission electron microscopy provided ultrastructural corroboration of endothelial cell apoptosis in static cold storage conditions. For static cold storage preserved veins, Krüppel-like factor 2 expression diminished in a time-dependent manner between baseline and 12 hours (P < 0.05) but was abrogated and reversed by hypothermic machine perfusion (P < 0.05).

CONCLUSIONS

Our methodology is a simple, reproducible and successful model of ex vivo perfusion in the context of human organ preservation. To demonstrate the model's utility, we establish that two widely used markers of endothelial health (caspase-3 and Krüppel-like factor 2) differ between the flow and no-flow conditions of the two predominant kidney preservation modalities. These findings suggest that ex vivo perfusion may mediate the induction of a biochemically favourable endothelial niche which may contribute tohypothermic machine perfusion's association with improved renal transplantation outcomes.

4118Cisplatin therapy as a risk factor for incident atrial fibrillation

Background

Although aging is a major contributor to the rising epidemic of atrial fibrillation (AF), increased numbers of cancer survivors who suffer from chemotherapy and radiotherapy mediated cardiovascular disease also appear to be especially vulnerable to developing the arrhythmia. Currently, little is known about the long-term risk of AF in patients treated with these two treatment modalities for cancer.

Purpose

To define the incidence and prevalence of AF in a thoracic tumour cohort following radiotherapy and chemotherapy.

Methods

We conducted a retrospective study from the electronic health records (EHR) of patients who had a primary tumour of the breast and lung. Patients with AF, radiotherapy or chemotherapy prior to cancer diagnosis were excluded. All patients were followed for incident AF until last censoring or death using a validated AF algorithm (positive predictive value 96%). Radiation oncology treatment reports were reviewed and chemotherapy data was extracted from the EHR and manually reviewed for 43 chemotherapeutic agents.

Results

In the tumour registry, 17,402 patients were identified by histological and pathological reports. We examined 3,336 patients with a thoracic tumour diagnosis (breast and lung) with a mean age of 62.7±12.5 (SD) years. The AF incident rate for breast and lung cancer was 1.2 and 13.5 cases per every 100 persons with a cumulative rate of 2.49 and 0.67 respectively. We observed an overall AF prevalence of 3.4% and 7.4% in the breast and lung cohorts respectively. The average follow-up duration was 4.69 years (0.0–17.8 years) in breast cancer and 1.36 years (0.0–13.9 years) in lung cancer patients. A Cox regression model revealed no association between radiotherapy and AF in either cancer type (breast: P=0.18 and lung: P=0.16). However, patients who received cisplatin had 4-fold increased risk of developing AF after covariate adjustment (HR = 4.22, 95% CI: 0.10–17.85, P=0.05).

Conclusions

We show for the first time in a large thoracic tumour registry and using the EHR that patients treated with cisplatin were more likely to develop AF. Additional studies are needed to validate our findings and to further investigate the underlying mechanisms of these cardiotoxic effects.

Acknowledgement/Funding

This work was supported in part by grants from the AHA 17MCPRP33420153 (Brandon Chalazan) and NIH/NHLBI R01 HL092217 and HL138737 (Dawood Darbar).

P4415Long obstructive sleep apneas as a biomarker of atrial fibrillation

Background

Even though obstructive sleep apnea (OSA) is strongly associated with atrial fibrillation (AF), the use of traditional OSA scoring by apnea hypopnea index (AHI) did not result in improved arrhythmia outcomes in recent randomized trials. Longer OSA episodes lead to stronger pro-arrhythmic changes, and whether very long OSA episodes are more prevalent in AF patients remains unknown.

Purpose

We hypothesized that AF patients with mild-moderate OSA manifest greater percentage of long (>20s), very long (>30s), and extremely long (>40s) OSA episodes, compared to control OSA patients matched to AHI, age and sex.

Methods

From patients studied with diagnostic polysomnography in our laboratory between 2016 and 2018, we selected 22 patients with mild-moderate untreated OSA of which 11 patients had history of paroxysmal AF and 11 patients did not have any cardiac history. The length, oxygen desaturation, and relationship to neighboring events was manually re-measured in all recorded apnea and hypopnea events.

Results

In the 22 included patients (age 62.5±9.1 years, AHI 12.8±6.1, 40% female) we recorded 1021 apneas: 508 in the AF group and 513 in the control group. AF patients had longer apneas compared to the patients without AF history (mean length 28.7±11.7s vs. 23.3±9.9s; p<0.0001). The proportion of apneas that were long (>20s), very long (>30s), and extremely long (>40s) was greater in the AF group as compared to the control (p=0.0039, p=0.0215, p=0.0104, respectively; see figure). The acute oxygen saturation drops (>2%) during apneas were comparable between the AF group and control groups (p=0.13), but the long (>20s) apneas were prone to greater oxygen desaturations.

Length of Apneas

Conclusions

While traditional scoring of OSA focuses on episodes lasting >10s, our data newly show that longer durations of OSA events are particularly prevalent in AF patients. These results, combined with recent mechanistic studies showing that longer apneas exert greater pro-arrhythmic effect on atrial conduction, suggest that novel scoring of OSA placing more weight on longer apneas should be explored, especially when screening and titrating OSA therapy in patients at risk of AF.

Relationships among bedding materials, bedding bacteria counts, udder hygiene, milk quality, and udder health in US dairy herds

Bedding is an important source of teat end exposure to environmental mastitis pathogens. To better control environmental mastitis, we need an improved understanding of the relationships among bedding selection and management, bedding bacteria counts (BBC), and udder health (UH). The objectives of this cross-sectional observational study were (1) to describe BBC, bedding characteristics, udder hygiene scores, bulk tank milk (BTM) quality, and UH in US dairy herds using 1 of 4 bedding materials; (2) describe the relationship between BBC and herd measures of UH; and (3) identify benchmarks for monitoring bedding hygiene. Local dairy veterinarians and university researchers enrolled and sampled 168 herds from 17 states. Herds were on a Dairy Herd Improvement Association (DHIA) testing program and used 1 of 4 bedding types for lactating cows: new sand, reclaimed sand, manure solids (MNS), or organic non-manure materials. Each herd was sampled twice (winter and summer) in 2016. Samples and data collected included unused and used bedding, BTM samples, udder hygiene scores, DHIA test data, and descriptions of facilities and herd management practices. Bedding was cultured to determine the total bacteria count and counts of Bacillus spp., coliforms, Klebsiella spp., non-coliform gram-negative organisms, streptococci or streptococci-like organisms (SSLO), and Staphylococcus spp. Bedding dry matter, organic matter, and pH were also measured. Bulk tank milk samples were cultured to determine counts of coliforms, NAS, SSLO, Staphylococcus aureus, and Mycoplasma spp. Udder health measures included DHIA test-day average linear score (LS); the proportion of cows with an intramammary infection (IMI), where infection was defined as LS ≥4.0; the proportion of cows with a new IMI, where new IMI was defined as LS changing from <4.0 to ≥4.0 in the last 2 tests; the proportion of cows with a chronic infection, where chronic was defined as LS ≥4.0 on the last 2 tests; and the cumulative incidence of clinical mastitis in the 30-d period preceding sample collection. Although much variation existed within and among bedding types, mixed linear regression showed the use of MNS bedding to be generally associated with higher BBC, dirtier udders, increased coliform and SSLO counts in BTM, and poorer UH measures compared with organic non-manure materials, reclaimed sand, or new sand bedding materials. While controlling for important farm traits and management practices, mixed linear regression showed that increased counts of coliforms, Klebsiella spp., SSLO, and Staphylococcus spp. in both unused and used bedding were associated with poorer values for 1 or more herd-level measures of UH. Achievable benchmarks identified for counts of coliforms (unused: ≤500 cfu/cm³; used: ≤10,000 cfu/cm³), Klebsiella spp. (0 cfu/cm³ for unused and used), Staphylococcus spp. (0 cfu/cm³ for unused and used), and SSLO (unused: 0 cfu/cm³; used: ≤500,000 cfu/cm³) can be used to monitor bedding hygiene in most bedding materials, with minor variations suggested for SSLO in unused MNS (≤1,000 cfu/cm³).

Sodium-Glucose Cotransporters as Potential Therapeutic Targets in Patients With Type 1 Diabetes Mellitus: An Update on Phase 3 Clinical Trial Data

Objective: To review phase 3 trials of sodium-glucose cotransporter (SGLT) inhibitors in type 1 diabetes mellitus (T1DM) patients. Data Sources: A literature search of Ovid MEDLINE databases (1946 through May 17, 2019) limited to English-language human clinical trials was conducted using the following terms: sodium-glucose transporter 2 inhibitors, canagliflozin, dapagliflozin, empagliflozin, sotagliflozin, ertugliflozin, ipragliflozin, or remogliflozin combined with type 1 diabetes mellitus. Results were verified via Google Scholar and clinicaltrials.gov. Study Selection and Data Extraction: Articles were included if they were phase 3 trials in adults with T1DM. Data Synthesis: Phase 3 trials are available for dapagliflozin, empagliflozin, and sotagliflozin. All 3 drugs demonstrated statistically significant reductions in hemoglobin A1C, weight, and total daily insulin dose without an increased risk of hypoglycemia in up to 52 weeks of therapy. The incidence of diabetic ketoacidosis (DKA) was higher in patients on a SGLT inhibitor at all doses, with the exception of empagliflozin 2.5 mg (0.8% vs 1.2% with placebo). Relevance to Patient Care and Clinical Practice: SGLT inhibitors are potential adjuncts to insulin in T1DM patients, providing clinically meaningful benefits. Regulatory bodies have either approved or are reviewing these agents for use in T1DM. Clinicians should be familiar with the DKA risk associated with SGLT inhibitors and utilize DKA risk-mitigation strategies. Empagliflozin 2.5 mg warrants additional investigation given its efficacy without an increased incidence of DKA. Conclusions: Phase 3 trial data of SGLT inhibitors provide evidence for sustained efficacy in T1DM patients. Appropriate patient selection for therapy and routine monitoring are essential to minimize associated risks.

Bedding and bedding management practices are associated with mesophilic and thermophilic spore levels in bulk tank raw milk

Mesophilic and thermophilic spore-forming bacteria represent a challenge to the dairy industry, as these bacteria are capable of surviving adverse conditions associated with processing and sanitation and eventually spoil dairy products. The dairy farm environment, including soil, manure, silage, and bedding, has been implicated as a source for spores in raw milk. High levels of spores have previously been isolated from bedding, and different bedding materials have been associated with spore levels in bulk tank (BT) raw milk; however, the effect of different bedding types, bedding management practices, and bedding spore levels on the variance of spore levels in BT raw milk has not been investigated. To this end, farm and bedding management surveys were administered and unused bedding, used bedding, and BT raw milk samples were collected from dairy farms (1 or 2 times per farm) across the United States over 1 yr; the final data set included 182 dairy farms in 18 states. Bedding suspensions and BT raw milk were spore pasteurized (80°C for 12 min), and mesophilic and thermophilic spores were enumerated. Piecewise structural equation modeling analysis was used to determine direct and indirect pathways of association among farm and bedding practices, levels of spores in unused and used bedding, and levels of spores in BT raw milk. Separate models were constructed for mesophilic and thermophilic spore levels. The analyses showed that bedding material had a direct influence on levels of spores in unused and used bedding as well as an indirect association with spore levels in BT raw milk through used bedding spore levels. Specific bedding and farm management practices as well as cow hygiene in the housing area were associated with mesophilic and thermophilic spore levels in unused bedding, used bedding, and BT raw milk. Notably, levels of spores in used bedding were positively related to those in unused bedding, and used bedding spore levels were positively related to those in BT raw milk. The results of this study increase the understanding of the levels and ecology of mesophilic and thermophilic spores in raw milk, emphasize the possible role of bedding as a source of spores on-farm, and present opportunities for dairy producers to reduce spore levels in BT raw milk.

Metastasis of squamous cell carcinoma of the head and neck to the thyroid: a single institution's experience with a review of relevant publications

The thyroid gland is a rare site of metastasis, and in particular of those of squamous cell carcinoma (SCC) from the head and neck region. We have reviewed the aetiology, pathogenesis, clinical characteristics, radiological features, immunohistochemical profile, prognosis, and management of metastatic SCC from the head and neck region to the thyroid, and searched current publications on the Medline, Embase, and Cochrane databases using the following keywords: "SCC of thyroid", "secondary SCC of thyroid", and "metastasis to the thyroid", for papers published during the last 33 years (April 1984 to October 2017).We found a total of 19 papers that reported a total of 32 cases that were relevant. Four further cases were discovered as an incidental finding on follow-up positron emission tomographic/computed tomographic scans with magnetic resonance imaging of the head and neck at our hospital, which were confirmed with an ultrasound-guided core needle biopsy followed by immunohistochemical examination. For patients who are doing well, whose disease is controlled at the primary site, and who have no evidence of distant metastatic disease, total thyroidectomy could be considered followed by adjuvant radiation or chemoradiotherapy, depending on the presence of intermediate or high-risk features on pathological examination and previous history of radiation. This may help to control the disease and avoid local morbidity.

Prospective cohort study of surgical trainee experience of access to gastrointestinal endoscopy training in the UK and Ireland

INTRODUCTION

Surgical trainees are reporting barriers to training in gastrointestinal (GI) endoscopy. This snapshot survey aimed to gather data on variation in access to quality GI endoscopy training for Colorectal and Upper Gastrointestinal (GI) surgical trainees across the UK and Ireland.

MATERIALS AND METHODS

An online 20-point survey was designed and distributed nationally to surgical trainee members of the Association of Surgeons in Training (ASiT), Dukes and The Roux Group (formerly Association of Upper Gastrointestinal Surgeons of Great Britain and Ireland Trainees). The survey was designed in collaboration with The Roux Group for Upper GI trainees and the Dukes' Club for Colorectal trainees.

RESULTS

218 responses were received, most with a Colorectal or Upper GI sub-specialty interest (colorectal 56.0%; upper GI surgery 25.7%). Only 28.6% of trainees attended a dedicated training endoscopy list at least once a week with 28.1% not attending any at all. Less than half of trainees reported having endoscopy formally timetabled on rotas (36.9%). Most trainees (88.0%) encountered difficulties in gaining endoscopy training including lack of available lists (77.2%), conflicting operative commitments (59.4%), preferential allocation of lists to gastroenterology trainees (57.9%) and resistance from endoscopy departmental leads (38.6%). Regarding JAG accreditation, 77.1% respondents felt it should be mandatory prior to CCT with 80.3% believing this would lead to better access to dedicated endoscopy training equivalent to gastroenterology trainees. 93.1% trainees felt that attaining JAG accreditation by surgical trainees was important to patient care.

DISCUSSION

This study demonstrates significant barriers in accessing GI endoscopy training for general surgical trainees which urgently needs to be improved. In order to meet JAG training requirements for surgical trainees, a multifaceted collaborative approach from surgical and gastroenterology training bodies, local JAG trainers and the General Surgery SAC and JCST is required. This is to ensure that endoscopy is promoted and a robust model of training is successfully designed and delivered to general surgery trainees.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Using an Integrated Care Pathway for Late-Life Schizophrenia Improves Monitoring of Adverse Effects of Antipsychotics and Reduces Antipsychotic Polypharmacy

OBJECTIVE

Antipsychotic use in older patients is associated with many adverse effects, including tardive dyskinesia and extrapyramidal symptoms, which, in turn, increase the risk of falling. Antipsychotics are also associated with metabolic syndrome and cognitive impairment in older patients. Integrated care pathways (ICPs) are designed to manage specific conditions using standardized assessments and measurement-based interventions. This study aims to compare the use of recommended tools to monitor for adverse effects associated with antipsychotics in older patients managed within an ICP and those managed under usual care conditions-i.e., treatment as usual (TAU).

METHODS

We reviewed and compared the health records of 100 older patients enrolled in an ICP for late-life schizophrenia with those of 100 older patients treated with antipsychotics under TAU conditions.

RESULTS

Monitoring rates were significantly higher in the ICP group than in the TAU group for all assessments: extrapyramidal symptoms (94% versus 5%), metabolic disturbances (91% versus 25%), fall risk (82% versus 35%), and cognitive impairment (72% versus 28%). Rates of antipsychotic polypharmacy were also six times higher in the TAU group.

CONCLUSION

Older patients with schizophrenia treated with antipsychotics within an ICP experience higher rates of monitoring and less psychotropic polypharmacy than older patients treated with antipsychotics under TAU conditions. These findings suggest that an ICP can improve the quality of antipsychotic pharmacotherapy in older patients and thus possibly its effectiveness. This needs to be confirmed by a randomized controlled trial.

Survival of patients with subglottic squamous cell carcinoma

Objective

Subglottic squamous cell carcinoma is a rare subsite of laryngeal cancer that behaves more aggressively and portends a worse prognosis. Using a population-based cancer registry, our objective was to report overall survival (os) and laryngectomy-free survival (lfs) in patients diagnosed with subglottic squamous cell carcinoma, and to determine whether primary laryngectomy results in improved survival.

Methods

This retrospective population-based study considered patients with a new diagnosis of squamous cell carcinoma in the province of Ontario over a 15-year period (1995-2009). The Ontario Cancer Registry was examined for patients with the diagnosis of interest during the period of interest. Linked population-based databases were used to obtain patient demographics, comorbidity measures, staging, survival, and primary treatment with laryngectomy.

Results

Of 4927 patients identified to have laryngeal carcinoma, 89 were defined as having primary subglottic carcinoma (1.8%). In the subglottic cohort, 68 patients were men (76.4%), and mean age at diagnosis was 68 years (interquartile range: 60-77 years). The 5-year os was 47.2%, and the 5-year lfs was 31.5%. In 13 patients (15%), the primary treatment was laryngectomy, which, compared with primary radiation, did not predict for improved os. No differences in os or lfs were observed during the 15-year study period (os p = 0.42, lfs p = 0.83).

Conclusions

The survival of patients with subglottic carcinoma is poor and has remained stable over time (1995-2009). Compared with primary radiation, primary treatment with laryngectomy does not appear to improve os.