758 Pre-Incisional Infiltration of Local Anaesthetic Is Associated with Reduced Intra-Operative Fentanyl Requirements and Lower Pain Scores in Recovery

Introduction

Effective pain management is a pivotal component of day-surgical pathways. Intra-operative regional infiltration of long-acting local anaesthetic (LA) has been shown to be efficacious in reducing post-operative pain after general anaesthesia, yet few studies have explored the optimal timing of its use.

Method

Patients undergoing day-case breast/general surgical operations under a single consultant surgeon were randomised to receive LA infiltration (Levobupivicaine) before the initial incision, or during wound closure. All patients were given a propofol-based general anaesthetic. Primary outcomes were intra-operative/post-operative fentanyl requirements, and numerical pain scores (at 1 and 3 hours post-operatively). The study ran from October 2019 but was suspended during the COVID-19 pandemic. Non-parametric statistical tests were used.

Results

25 patients were randomised. Those receiving pre-incisional LA had lower fentanyl requirements intra-operatively (mean; 150mcg vs 186mcg, p < 0.05) but similar requirements post-operatively. Mean pain scores were lower in the pre-incisional LA group at 1 hour (1.2 vs 2.3, p < 0.05) and 3 hours post-operatively (0.7 vs 1.3, p > 0.4).

Conclusions

Pre-incisional infiltration of LA led to a significantly reduced requirement for intra-operative fentanyl, and significantly lower pain scores at 1 hour post-operatively. Larger studies should interrogate this effect at individual procedure level and assess for differences in rates of chronic pain.

Immunisation Status of Children with Cerebral Palsy in Rural Bangladesh: Results from the Bangladesh Cerebral Palsy Register (BCPR)

BACKGROUND

Cerebral palsy (CP) is the most common cause of physical disability in childhood, with an estimated 17 million cases worldwide. There is limited data concerning the general health of this population and the immunisation status of children with CP is largely unknown.

OBJECTIVE

We aimed to assess the immunisation status of children with CP in rural Bangladesh and determine the predictors of non-immunisation.

METHODS

This study is part of the Bangladesh CP Register (BCPR) study; a population based CP register commenced in January 2015 in the Shahjadpur sub-district of Bangladesh. As part of BCPR registration, all children with CP in the catchment area were assessed by a paediatrician and their clinical and immunisation history were collected.

RESULTS

Between January and December 2015, 615 children with CP were registered on the BCPR. The median age of the children was 7.5 years, and 38.5% were female. 91.7% of those children had a BCG vaccine scar (as an objective marker for immunisation at birth). However, only 43.2% reported to have received the rubella vaccine during the 2014 national rubella immunisation campaign. Timing of CP diagnosis was found to be an independent predictor for immunisation uptake; those diagnosed before the age of 3 were more likely to have received the rubella vaccine (95% confidence interval [CI] 1.6 - 4.3, odds ratio [OR] 2.6, p <0.0001).

CONCLUSIONS

To the best of our knowledge, this is the first paper to use a formal CP register to examine the relationship between CP and immunisation status in a low or middle income country like Bangladesh. Our data suggest that more than half of children with CP in rural Bangladesh did not receive immunisation during a recent national campaign.

Aquatic contaminants in Solomon Islands and Vanuatu: Evidence from passive samplers and Microtox toxicity assessment

Water Quality issues in many Pacific countries are rising, with the increase in coastal populations and associated urban runoff but management requires contamination issues in the aquatic environment to be identified and prioritised. In Vanuatu and Solomon Islands there are few laboratories and resources to assess for the presence or impact of complex chemical contaminants. The extent and impact of chemical contamination of the marine and coastal environment is poorly described. Passive chemical samplers were used to measure a range of aquatic pollutants around the capital cities, Honiara (Solomon Islands) and Port Vila (Vanuatu). We detected a range of chemicals indicative of agricultural and industrial contamination and a few sites had concerning concentrations of specific hydrocarbons and pesticides. The rapid ecotoxicology test, Microtox, indicated toxic impacts in rivers, coastal sites and urban drains This work provides new data on chemical contamination and possible impacts of that contamination for both countries. The techniques could be applied widely across the region to generate critical data for environmental management, guide monitoring efforts and measure the impact of policy or land-use changes.

76 This is (Probably) Not the Frailty Solution You are Looking For: Utilisation of A Novel Stand-Alone Community-Based Ambulatory Care Unit

Introduction/Aim

Our organisation wished to expand its “Care Closer To Home” capability, especially for older and/or frail patients. Our novel Ambulatory Care Unit (ACU) in a community hospital, staffed by GPs & nurses, opened a year ago. The ACU has some Point of Care (POCT) diagnostics, access to plain-film radiography and OT/physio. During the planning of the unit,” acute frailty” was anticipated to be core business. We wished to determine whether this turned out to be the case.

Method

Interrogation of the ACU patient log (spreadsheet collated from Data Collection Forms) Dec 2018-Nov 2019.

Results

Conclusion/Discussion

Recording of CFS by ACU staff was poor, limiting the validity of our results. Nevertheless, it is obvious that most patients seen in our ACU are not frail, and do not require therapies input. Those that are frail, however, have an acceptable conversion-to-admission rate of 8.6%, comfortably below the national target (20%).

Barriers to greater utilisation of our service for frail patients may include lack of urgent but non-emergency transport options for the less mobile, lack of access to certain commonly-used tests (e.g. CT, troponin) and referrer anticipation of difficulty discharging the frail patient in crisis without a new or boosted care package and/or access to respite beds. These aspects of service planning need to be addressed if the potential utility of community-based units like ours for frail patients is to be maximised.

AAPS Perspective on the EURL Recommendation on the use of Non-Animal-Derived Antibodies

In May 2020, the EU Reference Laboratory for alternatives to animal testing (EURL ECVAM) published a recommendation report entitled "Recommendation on nonanimal-derived antibodies". In this report, the EURL ECVAM specifically states: "Therefore, taking into consideration the ESAC Opinion on the scientific validity of replacements for animal-derived antibodies, EURL ECVAM recommends that animals should no longer be used for the development and production of antibodies for research, regulatory, diagnostic and therapeutic applications. The provisions of Directive 2010/63/EU should be respected, and EU countries should no longer authorise the development and production of antibodies through animal immunisation, where robust, legitimate scientific justification is lacking." (1). Here, we are providing the American Association of Pharmaceutical Scientists (AAPS) opinion on the EURL ECVAM recommendation report. In brief, there has been a clear and strong progress in reduction of animal use in the drug discovery and development process, including significant reduction of animal use in production of antibody reagents. Yet, it is proposed that more data need to be generated, shared and discussed within the scientific community before a decision to implement the change to non-animal derived antibodies is made.

The role of oxidised self-lipids and alveolar macrophage CD1b expression in COPD

In chronic obstructive pulmonary disease (COPD) apoptotic bronchial epithelial cells are increased, and their phagocytosis by alveolar macrophages (AM) is decreased alongside bacterial phagocytosis. Epithelial cellular lipids, including those exposed on uncleared apoptotic bodies, can become oxidized, and may be recognized and presented as non-self by antigen presenting cells. CD1b is a lipid-presenting protein, previously only described in dendritic cells. We investigated whether CD1b is upregulated in COPD AM, and whether lipid oxidation products are found in the airways of cigarette smoke (CS) exposed mice. We also characterise CD1b for the first time in a range of macrophages and assess CD1b expression and phagocytic function in response to oxidised lipid. Bronchoalveolar lavage and exhaled breath condensate were collected from never-smoker, current-smoker, and COPD patients and AM CD1b expression and airway 8-isoprostane levels assessed. Malondialdehyde was measured in CS-exposed mouse airways by confocal/immunofluorescence. Oxidation of lipids produced from CS-exposed 16HBE14o- (HBE) bronchial epithelial cells was assessed by spectrophotometry and changes in lipid classes assessed by mass spectrometry. 16HBE cell toxicity was measured by flow cytometry as was phagocytosis, CD1b expression, HLA class I/II, and mannose receptor (MR) in monocyte derived macrophages (MDM). AM CD1b was significantly increased in COPD smokers (4.5 fold), COPD ex-smokers (4.3 fold), and smokers (3.9 fold), and AM CD1b significantly correlated with disease severity (FEV₁) and smoking pack years. Airway 8-isoprostane also increased in smokers and COPD smokers and ex-smokers. Malondialdehyde was significantly increased in the bronchial epithelium of CS-exposed mice (MFI of 18.18 vs 23.50 for control). Oxidised lipid was produced from CS-exposed bronchial epithelial cells (9.8-fold of control) and showed a different overall lipid makeup to that of control total cellular lipid. This oxidised epithelial lipid significantly upregulated MDM CD1b, caused bronchial epithelial cell toxicity, and reduced MDM phagocytic capacity and MR in a dose dependent manner. Increased levels of oxidised lipids in the airways of COPD patients may be responsible for reduced phagocytosis and may become a self-antigen to be presented by CD1b on macrophages to perpetuate disease progression despite smoking cessation.

Healthcare staff perceptions and misconceptions regarding antibody testing in the United Kingdom: implications for the next steps for antibody screening

BACKGROUND

Healthcare workers have been at increased risk of exposure, infection and serious complications from COVID-19. Antibody testing has been used to identify staff members who have been previously infected by SARS-CoV-2, and has been rolled out rapidly in the United Kingdom. A number of comment and editorial articles have been published that raise concerns about antibody testing in this context. We present perceptions of National Health Service (NHS) healthcare workers in relation to SARS-CoV-2 antibody testing.

METHODS

An electronic survey regarding perceptions towards SARS-CoV-2 antibody testing was distributed to all healthcare workers at a major NHS tertiary hospital following implementation of antibody testing.

RESULTS

In total, 560 healthcare workers completed the survey (80% female; 25% of Black and Minority Ethnic background; 58% from frontline clinical staff). Exploring whether they previously had COVID-19 was the primary reported reason for choosing to undergo antibody testing (85.2%). In case of a positive antibody test, 72% reported that they would feel relieved, whilst 48% felt that they would be happier to work in a patient-facing area. Moreover, 12% responded that a positive test would mean "social distancing is less important", with 34% of the responders indicating that in this case they would be both less likely to catch COVID-19 and happier to visit friends/relatives.

CONCLUSIONS

NHS staff members primarily seek out SARS-CoV-2 antibody testing for an appropriate reason. Based on our findings and given the lack of definite data regarding the extent of immunity protection from a positive SARS-CoV-2 antibody test, significant concerns may be raised regarding the reported interpretation by healthcare workers of positive antibody test results. This needs to be further explored and addressed to protect NHS staff and patients.

Tokophobia and fear of birth: a workshop consensus statement on current issues and recommendations for future research

Objective: To discuss and develop a statement on the current state of the evidence and opinion in Fear of Childbirth (FoC) and Tokophobia (Tocophobia), and to provide recommendations. Background: A group met in 2019 to discuss the state of clinical and academic knowledge relating to FoC/Tokophobia. Five key areas were agreed as the focus of the meeting. Methods: 12 internationally acknowledged experts, in this or a closely related area (e.g. PTSD) met to discuss their understanding of the evidence for FoC/ Tokophobia and current practice. The consensus described in this paper constitutes the expression of the general opinion of the participants and does not necessarily imply unanimity. Keys points: Work focussed on tokophobia is recent and there remains a wide range of issues, which were addressed in the workshop including complexity in defining prevalence, a theoretical lack of understanding, which creates challenge for robust assessment and the identification of risk factors. An improved aetiological and developmental understanding of the tokophobia is required to underpin appropriate, effective and evidence-based interventions. Evaluation of pathways of care and relevant interventions, should be a focus of future research. Conclusion: Significant gaps remain within the FoC/tokophobia knowledge base. Further research is necessary.

Extended Polysaccharide Analysis within the Liposomal Encapsulation of Polysaccharides System

The Liposomal Encapsulation of Polysaccharides (LEPS) dual antigen vaccine carrier system was assessed across two distinct polysaccharides for encapsulation efficiency, subsequent liposomal surface adornment with protein, adjuvant addition, and size and charge metrics. The polysaccharides derive from two different serotypes of Streptococcus pneumoniae and have traditionally served as the active ingredients of vaccines against pneumococcal disease. The LEPS system was designed to mimic glycoconjugate vaccines that covalently couple polysaccharides to protein carriers; however, the LEPS system uses a noncovalent co-localization mechanism through protein liposomal surface attachment. In an effort to more thoroughly characterize the LEPS system across individual vaccine components and thus support broader future utility, polysaccharides from S. pneumoniae serotypes 3 and 4 were systematically compared within the LEPS framework both pre- and post-surface protein attachment. For both polysaccharides, ≥85% encapsulation efficiency was achieved prior to protein surface attachment. Upon protein attachment with either a model protein (GFP) or a pneumococcal disease antigen (PncO), polysaccharide encapsulation was maintained at ≥61% encapsulation efficiency. Final LEPS carriers were also evaluated with and without alum as an included adjuvant, with encapsulation efficiency maintained at ≥30%, while protein surface attachment efficiency was maintained at ≥~50%. Finally, similar trends and distributions were observed across the different polysaccharides when assessed for liposomal zeta potential and size.

Potential risk-factors affecting Salmonella sp. and Escherichia coli occurrence and distribution in Midwestern United States swine feed mills

AIM

This study aimed to evaluate the patterns and potential risk factors associated with the occurrence of Salmonella sp. and Escherichia coli in selected United States swine feed mills.

METHODS AND RESULTS

A total of 405 samples were collected during fall 2018, spring and summer 2019 from selected sites including floors, equipment, shoes and feed in six feed mills in the US Midwest region. Each sample was analysed for the presence of Salmonella and E. coli with culture methods and confirmed by PCR. A survey regarding production volumes, hygiene practices and microbial testing capabilities was conducted in each facility All mills had at least one sampling site positive for either Salmonella or E. coli. Of the 405 samples, 4·7, and 14·1% were positive for Salmonella sp., and E. coli respectively. Sites with higher percentages of positive samples were the receiving, manufacturing, and control area floors. The survey responses indicated that the age of the mill might be a risk factor for bacterial contamination: the older the facility, the higher the number of positive samples. Other risk factors evaluated, such as the production capacity, did not appear to relate to bacterial prevalence.

CONCLUSION

The data documents the presence of E. coli and Salmonella in selected US swine feed mills, and an association between E. coli occurrence and number of ingredient suppliers to feed mill.

SIGNIFICANCE AND IMPACT OF THE STUDY

This information could be used to understand risk factors affecting the occurrence of Salmonella sp. and E. coli in feed mills and help implement monitoring and mitigation strategies for public health.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

THU0553 A HEALTH ECONOMIC ANALYSIS OF THE USE OF COLOUR DOPPLER ULTRASONOGRAPHY AS THE PRIMARY DIAGNOSTIC MODALITY IN PATIENTS WITH SUSPECTED GIANT CELL ARTERITIS

Background:

EULAR has recommended ultrasonography (US) as first imaging modality for diagnosis of Giant Cell Arteritis (GCA)1. For patients with a high pre-test probability who have a negative scan, the recommendation is to use another diagnostic modality like temporal artery biopsy (TAB) to make a diagnosis1. We know that a fast-track pathway incorporating US, results in better clinical outcomes2; but there are little data on the health-economics of this approach. Since 2017, we have used ultrasonography as the primary diagnostic modality for suspected GCA. In patients with a high pre-test probability with a negative ultrasonography, we perform a temporal artery biopsy.

Objectives:

To compare the cost of investigating GCA using first-line US and second-line TAB the use of TAB only. To compare the cost per definite diagnosis of GCA.

Methods:

Number of cases from 2007-2009 and 2017-2019 were calculated by the number of TAB performed and number of referrals to hospital GCA clinic, respectively. Costs of the procedure were calculated as per the nationally agreed tariff by the United Kingdom National Health Service. For ease of comparison, we used the 2018/19 tariff (£1284/TAB; £51 for US)

Results:

In 2007-2009, 162 cases were referred to clinic and had a TAB, of which 86 were positive. No cases had US. The 2018/19 corrected cost was £208008; the cost per positive diagnosis was £2418.70 (Table 1).

In 2017-2019, 419 patients were referred to the GCA clinic, 416 of whom had US for diagnosis. 3 individuals had a TAB as the first diagnostic modality and 66 others were referred for a TAB because of a high pre-test probability and negative US. The 2018/19 corrected cost of this pathway was £109812 and the cost per positive diagnosis was £773.32 (Table 1).

Table 1.

Numbers of cases investigated for suspected GCA by TAB or US and the costs corrected to 2018/19 UK NHS tariff.

YearsNo of referralsNo of TABNo of USNo of patients with GCATotal costCost of making 1 positive diagnosis2007-09162162086£208008£2418.702017-1941969416142£109812£773.32

If all cases in 2017-2019 had a TAB for suspected GCA, the 2018/19 corrected cost would have been £537996. The estimated 2018/19 corrected savings in our center was £142728/year. The estimated 2018/19 corrected savings per definite diagnosis of GCA has dropped by £1645.37 (Table 1).

Conclusion:

The EULAR recommendation of using first-line US for diagnosis of GCA followed by a TAB in cases with uncertain diagnosis after US, is highly cost-effective in the UK, resulting in cost savings of >£140K per year.

References:

[1]Dejaco C, et al. Ann Rheum Dis. 2018 May;77(5):636-643.

[2]Diamantopoulos AP, et al. Rheumatology (Oxford). 2016 Jan;55(1):66-70.

Disclosure of Interests:

None declared

Postoperative decrease of regional volumetric bone mineral density measured by quantitative computed tomography after lumbar fusion surgery in adjacent vertebrae

We investigated the effect of posterior lumbar fusion surgery on the regional volumetric bone mineral density (vBMD) measured by quantitative computed tomography. Surgery negatively affected the regional vBMD in adjacent levels. Interbody fusion was independently associated with vBMD decline and preoperative epidural steroid injections (ESIs) were associated with less postoperative vBMD decline.

INTRODUCTION

Few studies investigate postoperative BMD changes after lumbar fusion surgery utilizing quantitative computed tomography (QCT). Additionally, it remains unclear what preoperative and operative factors contribute to postoperative BMD changes. The purpose of this study is to investigate the effect of lumbar fusion surgery on regional volumetric bone mineral density (vBMD) in adjacent vertebrae and to identify potential modifiers for postoperative BMD change.

METHODS

The data of patients undergoing posterior lumbar fusion with available pre- and postoperative CTs were reviewed. The postoperative changes in vBMD in the vertebrae one or two levels above the upper instrumented vertebra (UIV+1, UIV+2) and one level below the lower instrumented vertebra (LIV+1) were analyzed. As potential contributing factors, history of ESI, and the presence of interbody fusion, as well as various demographic/surgical factors, were included.

RESULTS

A total of 90 patients were included in the study analysis. Mean age (±SD) was 62.1 ± 11.7. Volumetric BMD (±SD) in UIV+1 was 115.4 ± 36.9 mg/cm³ preoperatively. The percent vBMD change in UIV+1 was - 10.5 ± 12.9% (p < 0.001). UIV+2 and LIV+1 vBMD changes showed similar trends. After adjusting with the interval between surgery and the secondary CT, non-Caucasian race, ESI, and interbody fusion were independent contributors to postoperative BMD change in UIV+1.

CONCLUSIONS

Posterior lumbar fusion surgery negatively affected the regional vBMDs in adjacent levels. Interbody fusion was independently associated with vBMD decline. Preoperative ESIs were associated with less postoperative vBMD decline, which was most likely a result of a preoperative decrease in vBMD due to ESIs.

0105 Working Memory Impairment Due to Chronic Sleep Restriction, Dose Response to Recovery and Re-Exposure

Introduction

Chronic sleep restriction negatively effects working memory. Recovery sleep following sleep restriction partially restores working memory performance. This study examines the impact of chronic sleep restriction and subsequent recovery sleep dose on the N-Back Task (N-Back), a valid measure of working memory.

Methods

N=223 participants (29.9±6.9 years; 48.4% female), completed two baseline nights of 8h time in bed (TIB), followed by five nights of 4h TIB, and were then randomized to a sleep dose of 0, 2, 4, 6, 8, 10, or 12 h TIB. A subset of participants (n=73) were re-exposed to another five nights of 4h TIB. Participants completed the three versions of the N-Back (i.e. 1-Back, 2-Back, and B-back) every two hours during wakefulness and daily averages were computed. Mixed effects and linear regression models were used to assess the impact of sleep restriction and the sleep dose response on percent correct on the N-Back corrected for baseline.

Results

N=219 participants had valid working memory data. The 2-Back (β =-4.5%; P&lt;0.0001) and the 3-Back (β =-12.5%; P&lt;0.0001) were more difficult than the 1-Back. Working memory performance declined across days of sleep restriction for all N-Backs: 1-Back (β =-1.10%; P&lt;0.0001), 2-Back (β =-0.99%; P&lt;0.0001), and 3-Back (β =-1.10%; P&lt;0.0001). The sleep dose analysis revealed a positive association with N-Back performance for all N-Back versions, 1-Back (β =0.99%; P=0.0002), 2-Back (β =1.46%; P&lt;0.0001), and 3-Back (β =1.43%; P&lt;0.0001). Re-exposure to only one night of 4h TIB following recovery sleep resulted in performance decrements equal to performance prior to recovery sleep for all N-Back versions (Ps&gt;0.41).

Conclusion

These data indicate that working memory is adversely impacted by sleep restriction, and that sufficient recovery sleep, possibly across consecutive days, is necessary to maintain optimal working memory performance.

Support

Funded by National Institute of Health NIH R01NR004281 and National Space and Biomedical Research Institute NSRBI NCC 5–98

The Light Role CCP: A Blueprint for Far Forward Medical Support to Contemporary Operations

November 2018 saw the deployment of a medical team with a remit to provide far forward medical support to UK, Coalition and indigenous forces. The delivery of this capability demanded a solution unique within the UK Defence Medical Services. The 'light role' casualty collection points provided emergency medical care to 475 casualties over a 4-month period. The success of the deployment was dependant on the ability to remain light and agile which brought with it logistical considerations. The clinical caseload was predominantly secondary blast injury and gunshot wound (GSW). The positioning of a Role 1 facility close to the front line of troops enabled early Damage Control Resuscitation including the delivery of blood products. MEDEVAC to Role 2 was enabled by indigenous forces. The unique situation demanded bespoke solutions for documentation and blood warming. The lessons learnt during the deployment may form a blueprint for future contingency operations.