Heparin bonded lines offer a solution that is difficult to implement Rapid Response to Dobson,R "Half the cases of bacteraemia in hospitals in England are linked to devices)

[Full text] The BMJ news report[1] that devices, particularly central venous lines, are linked to over half the cases of hospital acquired bacteraemia has long been a source of concern to clinicians in intensive care. Unfortunately, one simple, effective and low-cost intervention is not being used because of restrictions on licensing and supply. A systematic review[2] of heparin bonding (1 trial) or heparin infusion (3 trials) versus no anti-thrombotic prophylaxis for central venous lines showed a strong trend for a reduction in bacteraemia (pooled RR 0.26; 95% CI: 007, 1.03). Our updated searches found one subsequent trial[3] (200 children), conducted at Great Ormond Street Hospital (GOSH) without commercial funding, in which heparin bonded lines reduced the risk of bacteraemia from 33% to 4% (risk difference 29%; 19%, 39%). As heparin bonded central venous lines are not licensed for use in the UK, GOSH has been able to maintain their supply only by agreeing to take full legal responsibility should problems arise. This means that lines can be used but only on a named-patient basis with their use audited. It is therefore not surprising that a recent survey of 36 consultant and specialist trainee anaesthetists from across the south east of England found that no other trust was using heparin bonded lines. Policy regarding heparin bonded lines undoubtedly requires more and better quality studies[4,5]. However, satisfactory alternatives are few. Heparin infusion requires staff time, additional equipment, and provides the opportunity for drug errors. In contrast, adverse effects of heparin bonded lines remain theoretical. Although heparin bonded lines are licensed and widely used in the USA, the UK licensing authority requires further studies which the company appears to be reluctant to pursue. Focused commercial and research efforts are required to resolve this impasse. Reference List 1. Dobson R. Half the cases of bacteraemia in hospitals in England are linked to devices. BMJ 2003;326:10. 2. Randolph AG, Cook DJ, Gonzales CA, Andrew M. Benefit of heparin in central venous and pulmonary artery catheters: a meta-analysis of randomized controlled trials. Chest 1998;113:165-71. 3. Pierce CM, Wade A, Mok Q. Heparin-bonded central venous lines reduce thrombotic and infective complications in critically ill children. Intensive Care Med. 2000;26:967-72. 4. Randolph AG, Cook DJ, Gonzales CA, Andrew M. Benefit of heparin in peripheral venous and arterial catheters: systematic review and meta- analysis of randomised controlled trials. BMJ 1998;316:969-75. 5. Shah PS, Ng E, Sinha AK. Heparin for prolonging peripheral intravenous catheter use in neonates (Cochrane Review). Cochrane Database.Syst.Rev. 2002;CD00277

Anomalous Light Scattering by Topological PT{\mathcal{PT}}-symmetric Particle Arrays

Robust topological edge modes may evolve into complex-frequency modes when a physical system becomes non-Hermitian. We show that, while having negligible forward optical extinction cross section, a conjugate pair of such complex topological edge modes in a non-Hermitian $\mathcal{PT}$-symmetric system can give rise to an anomalous sideway scattering when they are simultaneously excited by a plane wave. We propose a realization of such scattering state in a linear array of subwavelength resonators coated with gain media. The prediction is based on an analytical two-band model and verified by rigorous numerical simulation using multiple-multipole scattering theory. The result suggests an extreme situation where leakage of classical information is unnoticeable to the transmitter and the receiver when such a $\mathcal{PT}$-symmetric unit is inserted into the communication channel.Comment: 16 pages, 8 figure

Making co-enrolment feasible for randomised controlled trials in paediatric intensive care.

Enrolling children into several trials could increase recruitment and lead to quicker delivery of optimal care in paediatric intensive care units (PICU). We evaluated decisions taken by clinicians and parents in PICU on co-enrolment for two large pragmatic trials: the CATCH trial (CATheters in CHildren) comparing impregnated with standard central venous catheters (CVCs) for reducing bloodstream infection in PICU and the CHIP trial comparing tight versus standard control of hyperglycaemia

A Fatal Case of Brainstem Encephalitis Caused by Human Parechovirus

There is increasing recognition of human parechovirus (HPeV) as a neurotropic virus, especially type 3, which can cause sepsis and encephalitis in young infants. We present a case of neonatal brainstem encephalitis caused by HPeV and review the fifteen published cases in the literature. This is the first report of HPeV causing brainstem encephalitis. Earlier use of polymerase chain reaction testing for HPeV should be considered in appropriate cases

Life-threatening mesenchymal hamartoma of the chest wall in a neonate

Mesenchymal hamartomas of the chest wall are unusual tumours diagnosed in neonates. They mostly resolve spontaneously hence conservative management has been advocated. Some compress vital structures in the thoracic cavity or bleed warranting surgical intervention. We present a neonate with mesenchymal hamartoma of the chest wall presenting as unilateral multifocal lesions with life threatening complications. He responded well to surgical intervention and was successfully discharged

Identification of genetic risk factors in the Chinese population implicates a role of immune system in Alzheimer's disease pathogenesis

Alzheimer’s disease (AD) is a leading cause of mortality among the elderly. We performed a whole-genome sequencing study of AD in the Chinese population. In addition to the variants identified in or around the APOE locus (sentinel variant rs73052335, P = 1.44 × 10−14), two common variants, GCH1 (rs72713460, P = 4.36 × 10−5 ) and KCNJ15 (rs928771, P = 3.60 × 10−6 ), were identified and further verified for their possible risk effects for AD in three small non-Asian AD cohorts. Genotype–phenotype analysis showed that KCNJ15 variant rs928771 affects the onset age of AD, with earlier disease onset in minor allele carriers. In addition, altered expression level of the KCNJ15 transcript can be observed in the blood of AD subjects. Moreover, the risk variants of GCH1 and KCNJ15 are associated with changes in their transcript levels in specific tissues, as well as changes of plasma biomarkers levels in AD subjects. Importantly, network analysis of hippocampus and blood transcriptome datasets suggests that the risk variants in the APOE, GCH1, and KCNJ15 loci might exert their functions through their regulatory effects on immune-related pathways. Taking these data together, we identified common variants of GCH1 and KCNJ15 in the Chinese population that contribute to AD risk. These variants may exert their functional effects through the immune system

Students’ perceived changes and benefits in a mandatory service learning course

2016-2017 > Academic research: refereed > Refereed conference paper201804_a bcmaVersion of RecordPublishe

Effect of impregnated central venous catheters on thrombosis in paediatric intensive care: Post-hoc analyses of the CATCH trial

Purpose: The CATheter infections in CHildren (CATCH) trial reported reduced risks of bloodstream infection with antibiotic impregnated compared with heparin-bonded or standard central venous catheters (CVC) in paediatric intensive care. CVC impregnation did not increase the risk of thrombosis which was recorded in 24% of participants. This post-hoc analysis determines the effect of CVC impregnation on the risk of thrombosis leading to CVC removal or swollen limb. Methods: We analysed patients in the CATCH trial, blind to CVC allocation, to define clinically relevant thrombosis based on the clinical sign most frequently recorded in patients where the CVC was removed because of concerns regarding thrombosis. In post-hoc, three-way comparisons of antibiotic, heparin and standard CVCs, we determined the effect of CVC type on time to clinically relevant thrombosis, using Cox proportional hazards regression. Results: Of 1409 participants with a successful CVC insertion, the sign most frequently resulting in CVC removal was swollen limb (37.6%; 41/109), with lower rates of removal of CVC following 2 episodes of difficulty withdrawing blood or of flushing to unblock the CVC. In intention to treat analyses (n = 1485), clinically relevant thrombosis, defined by 1 or more record of swollen limb or CVC removal due to concerns about thrombosis, was recorded in 11.9% (58/486) of antibiotic CVCs, 12.1% (60/497) of heparin CVCs, and 10.2% (51/502) of standard CVCs. We found no differences in time to clinically relevant thrombosis according to type of CVC. Conclusions: We found no evidence for an increased risk of clinically relevant thrombosis in antibiotic impregnated compared to heparin-bonded or standard CVCs in children receiving intensive care

The Microvasculature of Human Oral Mucosa Using Vascular Corrosion Casts and India Ink Injection I. Tongue Papillae

The microvasculature of human tongue papillae originating from 9 males and 6 females, aged 0.5 to 2 years was studied by scanning electron microscopy (SEM) of vascular corrosion casts and by light microscopy (LM) of India ink injected specimens. All papillae showed a microvasculature characterized by primary, secondary and tertiary capillary loops. In the filiform papillae the loops were generally arranged in a corolla-like pattern with the tertiary loops demonstrating a hair-pin shape. The fungiform papillae showed basically a similar architectural pattern although the loops were somewhat more compact and complex in structure. A small, shallow depression of the tertiary loops at the top of these papillae was found to be occupied by a prominent rete ridge of the surface epithelium. There was a gradual transition from filiform to foliate papillae, the latter appearing as rows of coalesced filiform papillae. The circumvallate papillae easily identified by the surrounding furrow showed a rather complex and compact pattern of capillary loops of which typical hair-pin shaped tertiary loops dominated the periphery of the papilla. Small grooves or depressions in the vascular network were found to be occupied by rete ridges of the overlying mucosal epithelium

Territory-Wide Chinese Cohort of Long QT Syndrome: Random Survival Forest and Cox Analyses

Introduction: Congenital long QT syndrome (LQTS) is a cardiac ion channelopathy that predisposes affected individuals to spontaneous ventricular tachycardia/fibrillation (VT/VF) and sudden cardiac death (SCD). The main aims of the study were to: (1) provide a description of the local epidemiology of LQTS, (2) identify significant risk factors of ventricular arrhythmias in this cohort, and (3) compare the performance of traditional Cox regression with that of random survival forests. / Methods: This was a territory-wide retrospective cohort study of patients diagnosed with congenital LQTS between 1997 and 2019. The primary outcome was spontaneous VT/VF. / Results: This study included 121 patients [median age of initial presentation: 20 (interquartile range: 8–44) years, 62% female] with a median follow-up of 88 (51–143) months. Genetic analysis identified novel mutations in KCNQ1, KCNH2, SCN5A, ANK2, CACNA1C, CAV3, and AKAP9. During follow-up, 23 patients developed VT/VF. Univariate Cox regression analysis revealed that age [hazard ratio (HR): 1.02 (1.01–1.04), P = 0.007; optimum cut-off: 19 years], presentation with syncope [HR: 3.86 (1.43–10.42), P = 0.008] or VT/VF [HR: 3.68 (1.62–8.37), P = 0.002] and the presence of PVCs [HR: 2.89 (1.22–6.83), P = 0.015] were significant predictors of spontaneous VT/VF. Only initial presentation with syncope remained significant after multivariate adjustment [HR: 3.58 (1.32–9.71), P = 0.011]. Random survival forest (RSF) model provided significant improvement in prediction performance over Cox regression (precision: 0.80 vs. 0.69; recall: 0.79 vs. 0.68; AUC: 0.77 vs. 0.68; c-statistic: 0.79 vs. 0.67). Decision rules were generated by RSF model to predict VT/VF post-diagnosis. / Conclusions: Effective risk stratification in congenital LQTS can be achieved by clinical history, electrocardiographic indices, and different investigation results, irrespective of underlying genetic defects. A machine learning approach using RSF can improve risk prediction over traditional Cox regression models