Is a minimum duration of 5 days of unfractionated heparin infusion necessary before transition to oral anticoagulation in cerebral venous thrombosis? a retrospective chart review

In managing cerebral venous sinus thrombosis (CVT), the standard approach has been administering parenteral anticoagulation for at least five days, despite limited supporting evidence. This study aimed to determine the optimal duration of parenteral anticoagulation for CVT patients and its potential impact on their functional outcomes upon discharge. This retrospective observational cohort study was conducted across multiple healthcare centers and included adult CVT patients who received varying durations of parenteral anticoagulation: less than 5 days (n = 25) or 5 days or more (n = 16). The primary focus was on the duration of acute anticoagulation treatment, with secondary endpoints including hospital stay length and functional outcomes. The study found that a shorter duration of anticoagulation treatment (< 5 days) was linked to more favorable outcomes, as measured by the modified Rankin Scale (mRS) (68% vs. 25%, RR = 0.37, CI 0.15-0.90, p = 0.007). However, regression analysis showed non statistically significant associations for all variables except gender. Female patients were significantly more likely to receive a shorter duration of anticoagulation (Odds Ratio: 2.6, 95% CI: 2.2-3.1, P-Value: <0.001). These findings suggest a potential connection between shorter anticoagulation duration (< 5 days) and improved CVT patient outcomes, as indicated by their mRS scores at discharge. The observed relationship between female gender and shorter anticoagulation duration warrants further exploration. Nevertheless, caution is necessary when interpreting these findings due to the small sample size and specific patient characteristics. Further research in a larger and more diverse cohort is essential to validate these results and understand their implications fully.

Reviving Decades-Old Wisdom: Longitudinal Analysis of Renin-Angiotensin System Inhibitors and its effects on Acute Ischemic Stroke to Improve Outcomes

BACKGROUND

While Renin-Angiotensin System (RAS) inhibitors have a longstanding history in blood pressure control, their suitability as first-line in-patient treatment may be limited due to prolonged half-life and kidney failure concerns.

METHODS

Using a cohort design, we assessed the impact of RAS inhibitors, either alone or in combination with beta-blockers, on mortality, while exploring interactions, including those related to end-stage renal disease and serum creatinine levels. Eligible subjects were AIS patients aged 18 or older with specific subtypes who received in-patient antihypertensive treatment. The primary outcome was mortality rates. Statistical analyses included cross-sectional and longitudinal approaches, employing generalized linear models, G-computation, and discrete time survival analysis over a 20-day follow-up period.

RESULTS

In our study of 3058 AIS patients, those using RAS inhibitors had significantly lower in-hospital mortality (2.2%) compared to non-users (12.1%), resulting in a relative risk (RR) of 0.18 (95% CI 0.12-0.26). Further analysis using G-computation revealed a marked reduction in mortality risk associated with RAS inhibitors (0.0281 vs. 0.0913, Risk Difference (RD) of 6.31% or 0.0631, 95% CI 0.046-0.079). Subgroup analysis demonstrated notable benefits, with individuals having creatinine levels below and above 1.3 mg/dL exhibiting statistically significant RD (RD -0.0510 vs. -0.0895), and a significant difference in paired comparison (-0.0385 or 3.85%, CI 0.023-0.054). Additionally, longitudinal analysis confirmed a consistent daily reduction of 0.93% in mortality risk associated with the intake of RAS inhibitors.

CONCLUSION

RAS inhibitors are associated with a significant reduction in in-hospital mortality in AIS patients, suggesting potential clinical benefits in improving patient outcomes.

Unfractionated heparin versus enoxaparin for venous thromboembolism prophylaxis in intensive care units: a propensity score adjusted analysis

Venous thromboembolism (VTE) is a common complication in hospitalized patients. Pharmacologic prophylaxis is used in order to reduce the risk of VTE events. The main purpose of this study is to compare the prevalence of deep vein thrombosis (DVT) and pulmonary embolism (PE) in patients admitted to the intensive care unit (ICU) who received unfractionated heparin (UFH) versus enoxaparin as VTE prophylaxis. Mortality was evaluated as a secondary outcome. This was a Propensity Score Adjusted Analysis. Patients admitted to neurology, surgical, or medical ICUs and screened with venous doppler ultrasonography or computed tomography angiography for detection of VTE were included in the analysis. We identified 2228 patients in the cohort, 1836 (82.4%) patients received UFH and 392 (17.6%) patients received enoxaparin. Propensity score matching yielded a well-balanced cohort of 950 (74% UFH, 26% enoxaparin) patients. After matching, there was no difference in prevalence of DVT (RR 1.05; 95% CI 0.67-1.64, p = 0.85) and PE (RR 0.76; 95% CI, 0.44-1.30, p = 0.31). No significant differences in location and severity of DVT and PE between the two groups were detected. Hospital and intensive care unit stay was similar between the two groups. Unfractionated heparin was associated with a higher rate of mortality, (HR 2.04; 95% CI, 1.13-3.70; p = 0.019). The use of UFH as VTE prophylaxis in ICU patients was associated with a similar prevalence of DVT and PE compared with enoxaparin, and the site and degree of occlusion were similar. However, a higher mortality rate was seen in the UFH group.

Timing of anticoagulation for venous thromboembolism after recent traumatic and vascular brain Injury

Currently, there is no consensus guideline for initiating anticoagulation in patients with a traumatic or vascular brain injury. Initiating anticoagulation for management of venous thromboembolism (VTE) can vary significantly from 72 hours to 30 weeks due to the risk of hemorrhagic complications. The purpose of this study is to compare clinical outcomes using modified Rankin Score (mRS) in a patient population with early (≤ 3 days) versus late (> 3 days) initiation of therapeutic anticoagulation from the time VTE was diagnosed. This retrospective study included patients with a traumatic or vascular brain injury who developed either deep vein thrombosis (DVT) or pulmonary embolism (PE). Use of anticoagulation prior to admission, diagnosis with VTE on admission, or patients with a non-brain injury were exclusion criteria. Secondary outcomes measured were all-cause mortality, length of stay, and reasons for early interruption of anticoagulation. Therapeutic anticoagulation was started early in 76 (74%) patients compared to late initiation in 27 (26%) patients. Baseline characteristics were similar between the two groups. The mRS score 0-3 versus 4-6 was similar in patients who received early anticoagulation versus those who received it later. However, there was a trend favoring better outcomes in the early group [mRS 4-6; 78% vs. 93%; p = 0.085] and in subgroup analysis of patients with VTE diagnosed 4-7 days [mRS 4-6; 26% vs. 56%; p = 0.006] compared to the late group. In univariate and multivariable logistic regression, only age was associated with a significant worse outcome (median, IQR) 36 years (24-50) vs. 58 years (44-65) OR 1.07 (1.03-1.12); p < 0.001. In this study, early initiation of anticoagulation did not worsen clinical outcomes.

Open reduction and internal fixation without rigid maxillomandibular fixation: evidence based or merely a surgical dictum? A comparative pilot study on 24 cases

OBJECTIVE

The objective of the study was to evaluate the results and immediate postoperative complications following open reduction and internal fixation of mandibular fractures with or without postoperative maxillo-mandibular fixation MATERIALS AND METHODS: The study spanned over a period of 24 months, extending from October 2015 to October 2017. The study sample comprised 24 subjects between the age range of 18 to 65 years. They were randomly divided into two groups: Group A included subjects in whom open reduction and internal fixation was followed by maxilla-mandibular fixation for 15 days, and Group B subjects in whom only open reduction and internal fixation was done, followed by immediate mobilization. The outcomes evaluated were swelling, pain, simplified oral hygiene index and occlusion. The subjects were followed for all these outcomes on 1st, 7th and 15th days. The occlusion was assessed for 5 days. Any other intra/post-operative complications were additionally noted.

RESULTS

There was no statistical difference between the groups for swelling, pain and occlusion. The patients with postoperative maxilla-mandibular fixation had poorer oral hygiene when compared to the other group (p<0.001).

CONCLUSIONS

The use of maxilla-mandibular fixation post open reduction and internal fixation seems to offer no additional benefits to the patients. According to the results of the study, this traditional surgical dictum seems to be used by the surgeons due to the lack of any scientific evidence. However, further studies should be conducted to confirm this statement.

The role of mental health professionals in the climate crisis: an urgent call to action

The climate and ecological crisis will constitute the defining public health challenge of the twenty-first century, posing an unprecedented global threat to all determinants of health, and to healthcare delivery systems. We believe that mental health professionals have a crucial role to play in responding to this crisis. Whilst responding to the mental health consequences of the climate crisis will remain a key role for us as mental health professionals, we argue that our remit goes beyond this, and should include advancing public understanding of the climate crisis, highlighting its impact on physical and mental wellbeing, and advocating for systemic changes to limit its impending harms. This paper is an urgent call to action for all mental health professionals to take up a role in the context of the climate and ecological crisis. This paper will describe the relationship between mental health and climate change, and frame it within wider systemic and conceptual frameworks. It will demonstrate that as mental health professionals we are well placed to act as leaders of change-arguing that we have a duty to do so-and suggest actions that can be implemented depending on interests, skill sets and opportunities.

Reflections of mental health professionals on working with and in the climate crisis

The aim of this paper is to share our experiences of engaging with the climate crisis as citizens and mental health professionals (MHPs). We hope the outputs will usefully validate the experiences of fellow MHPs and support them to reflect on their role in this crisis. We came together as eight MHPs, participating in group discussions and one-one interviews with the first author to reflect on our experiences. The collaboratively generated themes reflect how engagement with the crisis has: (i) disrupted our personal and professional experiences; (ii) helped us adapt and grow; and (iii) enabled us to live, work and act in more accordance with our values. A key reflection was that these experiences are not linear and we continue to wrestle with our responses to the climate crisis. Discussions also elicited visions of how mental health paradigms could be better adapted to meeting the escalating public health need that this crisis is generating. We conclude by advocating for MHPs to process and respond to the climate crisis and recognize that their skills can make a vital contribution to this global challenge.

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.

326 Student Perceptions of Neurosurgery: Evaluating the Role of Undergraduate Neuroscience Societies

Introduction

Many institutions lack an organized system of informal network for medical students wishing to explore neurosurgery. We sought to evaluate the role of extracurricular neurosurgical events in influencing student perceptions of neurosurgery.

Method

Participants for this study were recruited from a neurosurgical careers seminar and practical workshop. Responses were collected prospectively using a multi-method strategy consisting of closed and open-ended questions. Additionally, semi-structured interviews were conducted to gain a deeper insight of students’ evaluation of these events and their perceptions of neurosurgery.

Results

A total of 124 students attended our extracurricular neurosurgery events. These events showed benefits in clinical knowledge and career planning. Students perceived the practical workshops to be useful in improving their basic surgical skills. Semi-structured interviews revealed that students felt their opportunities in exploring clinical neurosciences to be limited, which was seen as contributing towards the wider culture of neurophobia.

Conclusions

Undergraduate neuroscience societies provide useful educational platforms for students interested in neurosurgery, even in regions lacking institutional neuroscience networks. To help mitigate the wider culture of neurophobia, undergraduate neuroscience societies should focus on non-academic aspects of neurosurgery that are more personal and engaging, in an effort to spark interest in those who have had little exposure to the specialty.

Abstract P386: Reducing Laboratory Testing in Hospitalized Stroke Patients Using Machine Learning

Introduction: Despite previous studies indicating a high rate of overuse, in-hospital laboratory blood testing remains common. Repeated laboratory tests often return normal and lead to increased cost and even anemia. We hypothesize this situation is highly significant among hospitalized stroke patients. We used machine learning to reduce the freqeuency of repeated lab testing for stroke patients as a proof of concept.

Method: We used stroke patients in the MIMIC III database to develop a novel deep learning algorithm that takes into account the characteristics of all study patients to predict whether repeating a lab test is necessary and aid in decisions of obtaining subsequent laboratory tests. Our model jointly considers temporal and spatial correlations of lab tests to make predictions of future test abnormality. We included 12 tests for electrolytes, renal function, and Complete Blood Count. We defined an error as recommending the reduction of a laboratory study when the testing would have yielded a critical abnormal result which should have been tested (Table 1).

Results: We analyzed 3,178 stroke patients (293,433 lab results). Our training cohort was used to develop the algorithm and the testing data were used to generate results. In the testing cohort, we could maintain a 99.8% accuracy with a 52% reduction of all lab tests, which corresponded to a total reduction of 29,803 lab tests (74 false negatives). Different labs can be reduced at different rates. K and Cl were relatively easy to predict a critical abnormality on repeat testing while Ca and Mg displayed boundaries that were harder to predict abnormalties.

Conclusions: Reducing lab testing by 52% from this stroke patient cohort maintained accuracy of testing at 99.8%. Our data suggest that multiple or daily laboratory orders are unlikely to change patient management given the high accuracy proposed by the machine learning approach.

Table 1: normal range and critical abnormality for the 12 tests of interest

Guidelines for the Acute Treatment of Cerebral Edema in Neurocritical Care Patients

BACKGROUND

Acute treatment of cerebral edema and elevated intracranial pressure is a common issue in patients with neurological injury. Practical recommendations regarding selection and monitoring of therapies for initial management of cerebral edema for optimal efficacy and safety are generally lacking. This guideline evaluates the role of hyperosmolar agents (mannitol, HTS), corticosteroids, and selected non-pharmacologic therapies in the acute treatment of cerebral edema. Clinicians must be able to select appropriate therapies for initial cerebral edema management based on available evidence while balancing efficacy and safety.

METHODS

The Neurocritical Care Society recruited experts in neurocritical care, nursing, and pharmacy to create a panel in 2017. The group generated 16 clinical questions related to initial management of cerebral edema in various neurological insults using the PICO format. A research librarian executed a comprehensive literature search through July 2018. The panel screened the identified articles for inclusion related to each specific PICO question and abstracted necessary information for pertinent publications. The panel used GRADE methodology to categorize the quality of evidence as high, moderate, low, or very low based on their confidence that the findings of each publication approximate the true effect of the therapy.

RESULTS

The panel generated recommendations regarding initial management of cerebral edema in neurocritical care patients with subarachnoid hemorrhage, traumatic brain injury, acute ischemic stroke, intracerebral hemorrhage, bacterial meningitis, and hepatic encephalopathy.

CONCLUSION

The available evidence suggests hyperosmolar therapy may be helpful in reducing ICP elevations or cerebral edema in patients with SAH, TBI, AIS, ICH, and HE, although neurological outcomes do not appear to be affected. Corticosteroids appear to be helpful in reducing cerebral edema in patients with bacterial meningitis, but not ICH. Differences in therapeutic response and safety may exist between HTS and mannitol. The use of these agents in these critical clinical situations merits close monitoring for adverse effects. There is a dire need for high-quality research to better inform clinicians of the best options for individualized care of patients with cerebral edema.

Abstract WP362: Over-Utilization of Studies to Detect Deep Venous Thrombosis in Stroke Patients With Patent Foramen Ovale

Introduction: Cryptogenic stroke may result from paradoxical embolism through a patent foramen ovale (PFO). However, the association between deep vein thrombosis (DVT) and cryptogenic stroke has not been proven. The objective of our study is to compare the incidence of DVT in young and old patients who presented with acute ischemic stroke and were found to have a PFO.

Method: We conducted a single-centre retrospective study from January 2014-December 2018. Patients over the age of 18 with ischemic stroke and PFO, who underwent magnetic resonance venography (MRV) of the pelvis and venous doppler ultrasonography (VDU) for assessment of DVT were included. Primary endpoint was the incidence of DVT in patients that were age ≤ 60 (young group) compared to those age > 60 (old group). We further analyzed the incidence of DVT in cryptogenic stroke vs determined origin; and based on the Risk of Paradoxical Embolism (ROPE) score.

Results: We included 327 patients: 200 were young (Y) and 127 were old (O). Incidence of DVT was similar for patients in Y versus those in O group (7% vs 8%). A significantly higher ROPE score ≥ 6 was seen in the Y group (71% vs 9%; p<0.001). However, there was no difference in the incidence of DVT in patients with high (9%) or low ROPE scores (8%); OR 0.75, 95% CI (0.32-1.76) p=0.517. Among cryptogenic stroke with high ROPE score and young, incidence of DVT was (7% vs 9%) in determined origin; OR 0.74, 95% CI (0.28-1.96) p=0.557. MRV pelvis detected a clot in 5% of all patients. In a multivariable regression analysis; age, gender, and presence of PFO was not associated with the incidence of DVT. Length of stay and mRS at day 7 were the same between Y and O groups.

Conclusions: Detection of DVT was not associated with PFO, high ROPE scores or cryptogenic strokes. Our data indicate an over-reliance of testing for DVT, particularly MRV pelvis with contrast, in patients with PFO. Clinical studies are needed to identify other factors predictive of DVT in patients with ischemic stroke and PFO.

Comparison of polyspecific versus IgG specific ELISA in predominately cardiac patients with suspected heparin induced thrombocytopenia

A diagnosis of heparin induced thrombocytopenia (HIT) must often be made based on clinical and laboratory evidence. This was a quasi-experimental study of patients admitted from June 2016 to October 2017. The primary endpoint was the incidence of false positive results in polyspecific and IgG specific enzyme-linked immunosorbent assay (ELISA); then we compared the sensitivity and specificity of each assays in predominately cardiac patients with suspected HIT. A sensitivity/specificity analysis was conducted using serotonin release assay (SRA) as the 'gold standard'. The secondary outcome measures included length of hospital stay. We identified a total of 155 patients who met the inclusion criteria. Confirmatory tests with SRA on both groups were completed; false positive result was higher in the polyspecific group when compared to the IgG group [60% vs. 5%]. The IgG specific ELISA test yielded a sensitivity of 100% and a specificity of 95% however, the polyspecific ELISA had a low yield for specificity of 24% but maintained 100% sensitivity. In the IgG specific group with HIT-, their median length of stay was halved compared to those who were HIT + ; hospital LOS in days, IQR [30 (27-81) vs. 15 (7-33) p = 0.023] and a shorter median LOS in the ICU, IQR [24 (5-47) vs. 6 (2-14); p = 0.079]. Hospital or ICU LOS was the same in both (HIT+ and HIT-) groups managed with polyspecific ELISA. The IgG specific test had few false positive results and a high sensitivity score. Ensuring appropriate testing can bring a substantial decrease in drug expenditure, reduced length of stay and prevent unnecessary anticoagulation.

Review article: novel oral-targeted therapies in inflammatory bowel disease

BACKGROUND

There is a great unmet clinical need for efficacious, tolerable, economical and orally administrated drugs for the treatment of inflammatory bowel disease (IBD). New therapeutic avenues have become possible including the development of medications that target specific genetic pathways found to be relevant in other immune mediated diseases.

AIMS

To provide an overview of recent clinical trials for new generation oral targeted medications that may have a future role in IBD management.

METHODS

Pubmed and Medline searches were performed up to 1 March 2018 using keywords: "IBD", "UC", "CD", "inflammatory bowel disease" "ulcerative colitis", "Crohn's disease" in combination with "phase", "study", "trial" and "oral". A manual search of the clinical trial register, article reference lists, abstracts from meetings of Digestive Disease Week, United European Gastroenterology Week and ECCO congress were also conducted.

RESULTS

In randomised controlled trials primary efficacy endpoints were met for tofacitinib (JAK 1/3 inhibitor-phase III), upadacitinib (JAK 1 inhibitor-phase II) and AJM300 (α4-integrin antagonist-phase II) in ulcerative colitis. Ozanimod (S1P receptor agonist-phase II) also demonstrated clinical remission. For Crohn's disease, filgotinib (JAK1 inhibitor-phase II) met primary endpoints and laquinimod (quinolone-3-carboxide small molecule-phase II) was also efficacious. Trials using mongersen (SMAD7 inhibitor) and vidofludimus (dihydroorotate dehydrogenase inhibitor) have been halted.

CONCLUSIONS

This is potentially the start of an exciting new era in which multiple therapeutic options are at the disposal of physicians to treat IBD on an individualised basis. Head-to-head studies with existing treatments and longer term safety data are needed for this to be possible.

Elevated Blood Urea Nitrogen/Creatinine Ratio Is Associated with Venous Thromboembolism in Patients with Acute Ischemic Stroke

Objective

Although venous thromboembolism (VTE) is frequently related to dehydration, the impact of dehydration on VTE in acute ischemic stroke (AIS) is not clear. This study investigated whether dehydration, as measured by blood urea nitrogen (BUN)/creatinine (Cr) ratio, influences the occurrence of VTE in patients with AIS.

Methods

This is a retrospective study of patients with AIS between January 2012 and December 2013. Patients with newly diagnosed AIS who experienced prolonged hospitalization for at least 4 weeks were included in this study.

Results

Of 182 patients included in this study, 17 (9.3%) suffered VTE during the follow-up period; in two cases, VTE was accompanied by deep vein thrombosis and pulmonary embolism. Patients with VTE were more frequently female and had higher National Institutes of Health Stroke Scale (NIHSS) score, more lower limb weakness, and elevated blood urea nitrogen BUN/Cr ratio on admission. In a multivariate analysis, BUN/Cr ratio >15 (odds ratio [OR] 8.75) and severe lower limb weakness (OR 4.38) were independent risk factors for VTE.

Conclusion

Dehydration on admission in cases of AIS might be a significant independent risk factor for VTE.

Ustekinumab: a novel therapeutic option in Crohn's disease

INTRODUCTION

Although anti-tumour necrosis factor (TNF) agents have caused a paradigm shift in the management of moderate-to-severe Crohn's, they are sometimes associated with diminished or absent response in a considerable proportion of patients. Hence agents targeting pathways other than TNF are needed. Ustekinumab is a monoclonal antibody directed against the p40 subunit of IL-12 and 23.

AREAS COVERED

This manuscript summarises the available evidence on the efficacy and safety of Ustekinumab in Crohn's disease through data available from randomised controlled trials and compassionate use programs across the world.

EXPERT OPINION

Current literature strongly supports the fact that ustekinumab is clinically efficacious and reasonably safe for induction and maintenance of remission in moderate-to-severe Crohn's disease.

Assessment of the Relationship between Body Mass Index and Incidence of Venous Thromboembolism in Hospitalized Overweight and Obese Patients

STUDY OBJECTIVE

To assess whether a positive linear association exists between body mass index (BMI) and incidence of venous thromboembolism (VTE) in overweight and obese hospitalized patients.

DESIGN

Single-center retrospective observational cohort study.

SETTING

Large academic tertiary care medical center.

PATIENTS

A total of 1452 adults hospitalized between January 1, 2013, and December 31, 2014, who weighed more than 100 kg and had a BMI of 25 kg/m² or greater on admission, and received heparin subcutaneously for VTE prophylaxis. Patients were categorized into four subgroups based on World Health Organization BMI classification: overweight (141 patients), obese class I (305 patients), obese class II (324 patients), and obese class III (682 patients).

MEASUREMENTS AND MAIN RESULTS

The primary outcome was occurrence of VTE in each subgroup; all-cause mortality and length of hospital stay were secondary outcomes. A linear trend test did not show an association between occurrence of VTE and BMI of 25 kg/m² or greater. VTE occurred in 7 (5%) of 141 patients in the overweight group, 5 (2%) of 305 in the obese class I group, 8 (3%) of 324 in the class II group, and 18 (3%) of 682 in the class III group (p=0.573). In addition, no linear association was noted between all-cause mortality or length of hospital stay and BMI of 25 kg/m² or greater. Overall mortality was 10% (146/1452 patients). Ten deaths (7%) occurred in the overweight group, 45 (15%) in the obese class I group, 38 (12%) in the obese class II group, and 53 (8%) in the obese class III group (p=0.067). The median length of hospital stay was 5 days (interquartile range 3-9, p=0.122) for all patients.

CONCLUSION

In overweight and obese hospitalized patients who weighed more than 100 kg and had a BMI of 25 kg/m² or greater, the incidence of VTE did not increase incrementally with increasing severity of obesity.

Impact of practice change in reducing venous thromboembolism in neurocritical overweight patients: 2008-2014

Publications regarding early initiating venous thromboembolism (VTE) prophylaxis have been available since the early 1990s. These recommendations became available in current guidelines on and after 2012. The purpose of this study is to review the practice change in reducing the incidence of VTE in brain injury patients from 2008 to 2014. This was a single-center, retrospective, observational, cohort study. Data was extracted from our data base that included patients over 100 kg from January 2008 to August 2014. Included were all patients admitted with a primary diagnosis of acute brain and spinal injury to neurocritical care unit. Clinical endpoints examined were incidence of bleeding and VTE. A total of 509 patients who met the inclusion criteria were divided into two groups: The previous group (n = 212) included patients from 2008 to 2010, and the recent group (n = 297) included patients from 2011 to 2014. The time for initiating VTE prophylaxis from admission was (median, IQR) 73 h (37-140) vs. 34 h (20-46); p < 0.01. There were no differences in major and minor bleeding complications. Discontinuation of VTE prophylaxis for association with progressive bleeding was not documented in any of the study patients. The incidence of VTE was 10 % (22/212) vs. 5 % (15/297); p = 0.02. In hospital LOS in days was 16 (10-26) vs. 7 (4-15); P < 0.01. In multivariable logistic regression analysis, only the time of the initiation VTE prophylaxis after admission was significantly associated with the occurrence of VTE (median, IQR) 70 h (37-158) vs. 36 h (20-63); OR 1.004, 95 % CI 1.001-1.007; P < 0.01. In this 6-year review of data, early initiation of VTE prophylaxis has decreased the incidence of VTE without clinically documented bleeding complications.

Biodistribution Study of Intravenously Injected Cetuximab-IRDye700DX in Cynomolgus Macaques

PURPOSE

The use of receptor-targeted antibodies conjugated to photosensitizers is actively being explored to enhance treatment efficacy. To facilitate clinical testing, we evaluated cetuximab conjugated to IRDye700DX (IR700) in cynomolgus macaques.

PROCEDURES

Total IR700 and intact cetuximab-IR700 were measured in 51 tissues at 2 and 14 days after intravenous injection of 40 and 80 mg/kg cetuximab-IR700, respectively, and compared with an unlabeled cetuximab-dosed control group (two each per sex per time point per group).

RESULTS

The IR700 retrieved from all tissues at 2 and 14 days after dosing was estimated at 34.9 ± 1.8 and 2.53 ± 0.67% of the total dose, respectively. The tissues with the highest levels of intact cetuximab-IR700 at 2 days after dosing were the blood, lung, and skin. Formalin-fixed paraffin-embedded tissue sections at 2 days after dosing showed the highest IR700 signals in the axillary lymph node, mammary gland, and gall bladder.

CONCLUSIONS

Both IR700 and intact cetuximab-IR700 biodistributions were consistent with known epidermal growth factor receptor (EGFR) expression, and changes between 2 and 14 days were consistent with rapid metabolism and excretion of the cetuximab-IR700.

ZNF750 is a lineage-specific tumour suppressor in squamous cell carcinoma

ZNF750 controls epithelial homeostasis by regulating epidermal-differentiation genes, a role underscored by its pathogenic mutations in esophageal squamous cell cancers (SCCs). However, the precise role of ZNF750 in SCC cell biology remains unclear. In this study, we report that ZNF750 is exclusively deleted, mutated and underexpressed in human SCCs, and low ZNF750 expression is associated with poor survival. Restoration of wildtype, but not mutant ZNF750 protein uniquely inhibited the malignant phenotypes of SCC cells both in vitro and in vivo. Notably, ZNF750 promoted the expression of a long non-coding RNA (TINCR), which mediated both cancer-inhibition and differentiation-induction effects of ZNF750. In addition, ZNF750 potently suppressed cell migration by directly inhibiting the transactivation of LAMC2. Together, our findings characterize ZNF750 as a crucial SCC-specific suppressor and uncover its novel anticancer-associated functions.

Antifactor Xa levels vs. activated partial thromboplastin time for monitoring unfractionated heparin. A pilot study

WHAT IS KNOWN AND OBJECTIVES

The two most common methods for monitoring unfractionated heparin (UFH) infusion are the activated partial thromboplastin time (aPTT) and the antifactor Xa heparin assay (anti-Xa). The purpose of this study is to compare the performance of an aPTT protocol vs. an anti-Xa protocol in adult patients as defined by the time to reach therapeutic range, the percentage of time the values were within the goal range and the number of times laboratory monitoring was conducted. We then analysed the discordance between paired values of anti-Xa and aPTT.

METHODS

This was a single-centre prospective cohort pilot study conducted from 1 September 2013 to 31 May 2014.

RESULTS

Eighty-five patients were treated with UFH infusion, aPTT monitoring (n = 48), anti-Xa monitoring (n = 37). The number of times aPTT and anti-Xa values were ordered was (median, IQR) 14 (2-34) vs 7 (2-76); P = 0·23. The time to reach therapeutic range in hours was (mean, SD) 22 (20) aPTT vs 15 (13) anti-Xa; P = 0·08. Therapeutic range (>50-100% of the time) was achieved in only 5 (10%) patients in the aPTT group vs. 21 (57%) in the anti-Xa group; P < 0·01. Supratherapeutic values (>50-100%) were observed in 38 (78%) patients in the aPTT group vs. 14 (38%) in the anti-Xa group; P < 0·01. The discordance between aPTT and anti-Xa was evaluated using 234 paired values from 37 patients. There was discordance between anti-Xa and aPTT values 57% of the time. Two patients had bleeding complications requiring blood transfusion or discontinuation of post-pilot protocol.

WHAT IS NEW AND CONCLUSION

Utilizing an anti-Xa protocol to monitor heparin infusion showed favourable results compared with utilizing an aPTT protocol by maintaining values within the therapeutic goal range. The most common discordant pattern in our study was a disproportionate prolongation of aPTT to anti-Xa values. Patients with discordant values presenting with high aPTT to normal anti-Xa values may have an increased risk of bleeding complications.

Supplementation of ascorbic acid and α-tocopherol prevents arsenic-induced protein oxidation and DNA damage induced by arsenic in rats

Contamination of arsenic in drinking water is associated with several human diseases including cancer. It has been reported that oxidative stress plays a vital role in arsenic-induced biochemical and molecular alterations. The aim of the present study was to improve the understanding of arsenic-induced oxidative damage to proteins and to DNA and the role of antioxidants such as ascorbic acid and α-tocopherol in alleviating arsenic-induced damages in experimental rats. A significant increase in the levels of protein oxidation, DNA strand breaks, and DNA–protein cross-links was observed in blood, liver, and kidney of rats exposed to arsenic (100 ppm in drinking water) for 30 days. Co-administration of ascorbic acid and α-tocopherol to arsenic-exposed rats showed a substantial reduction in the levels of arsenic-induced oxidative products of protein and DNA. The results of this study support that free radical–mediated toxic manifestations of arsenic and also suggest that ascorbic acid and α-tocopherol supplementation can improve the arsenic-induced molecular alterations.

Safety and Efficacy of High-Dose Unfractionated Heparin for Prevention of Venous Thromboembolism in Overweight and Obese Patients

STUDY OBJECTIVE

To determine the safety and efficacy of high-dose subcutaneous unfractionated heparin (UFH) for prevention of venous thromboembolism (VTE) in overweight and obese patients.

DESIGN

Single-center retrospective observational cohort study.

SETTING

Large academic tertiary care medical center.

PATIENTS

A total of 1335 adults who weighed more than 100 kg on admission and received either subcutaneous UFH 7500 units every 8 hours (751 patients [high-dose group]) or 5000 units every 8 hours (584 patients [low-dose group]) for VTE prophylaxis during their hospitalization between January 1, 2013, and August 31, 2014.

MEASUREMENTS AND MAIN RESULTS

The incidences of VTE and bleeding complications were assessed in each group. Each group was further divided into four groups based on their body mass index (BMI): overweight (BMI 25-29.9 kg/m(2) ), obese class I (BMI 30-34.9 kg/m(2) ), obese class II (BMI 35-39.9 kg/m(2) ), and obese class III (BMI ≥ 40 kg/m(2) ). The incidence of VTE was similar for patients in the high-dose group versus those in the low-dose group for all BMI categories. Bleeding complications were significantly higher for patients in the high-dose group. The proportion of patients with at least a 2-g/dl hemoglobin drop from admission was higher in patients in the high-dose groups in obese classes II and III: obese class II, 46 (30%) of 152 patients in the high-dose group versus 30 (18%) of 171 patients in the low-dose group (p<0.01); obese class III, 109 (25%) of 432 patients in the high-dose group versus 31 (12%) of 249 patients in the low-dose group (p<0.01). In addition, the proportion of patients who received at least 2 units of packed red blood cell transfusion was significantly higher in patients in the high-dose group who were in obese class III: 47 (11%) of 432 in the high-dose group versus 13 (5%) of 249 in the low-dose group (p<0.01).

CONCLUSION

Administering a higher dose of heparin to patients weighing more than 100 kg may not impart additional efficacy in reducing the incidence of VTE. However, it may increase the risk for bleeding.

Recombinant human antibody fragment against tetanus toxoid produced by phage display

Phage display technology is a powerful in vitro method for the identification of specific monoclonal antibodies (antibody fragments) to an antigenic target and allows the rapid generation and selection of high affinity, fully human antibodies directed toward any disease target appropriate for antibody therapy. In the present study, we exploited the phage display technology for the selection of an antigen binding fragment (Fabs) toward tetanus toxoid using human naïve phage antibody library constructed from peripheral blood lymphocytes of naïve human donors. The phages displaying Fab were subjected to three rounds of bio-panning with tetanus toxoid as antigen on a solid phase. The high affinity antibody fragments were expressed in HB2151 strain of Escherichia coli and purified by immobilized metal affinity chromatography. The binding activity and specificity of the antibody fragment was established by its reactivity toward tetanus toxoid and non-reactivity toward other related toxins as determined by enzyme-linked immunosorbent assay and immunoblot analysis. The selected Fab fragment forming the antigen-binding complexes with the toxoid in flocculation assay indicates that the Fab may have a potential neutralizing ability toward antigen.

Intravenous ketamine for the treatment of refractory status epilepticus: a retrospective multicenter study

PURPOSE

To examine patterns of use, efficacy, and safety of intravenous ketamine for the treatment of refractory status epilepticus (RSE).

METHODS

Multicenter retrospective review of medical records and electroencephalography (EEG) reports in 10 academic medical centers in North America and Europe, including 58 subjects, representing 60 episodes of RSE that were identified between 1999 and 2012. Seven episodes occurred after anoxic brain injury.

KEY FINDINGS

Permanent control of RSE was achieved in 57% (34 of 60) of episodes. Ketamine was felt to have contributed to permanent control ("possible" or "likely" responses) in 32% (19 of 60) including seven (12%) in which ketamine was the last drug added (likely responses). Four of the seven likely responses, but none of the 12 possible ones, occurred in patients with postanoxic brain injury. No likely responses were observed when infusion rates were lower than 0.9 mg/kg/h, when ketamine was introduced at least 8 days after SE onset, or after failure of seven or more drugs. Ketamine was discontinued due to possible adverse events in five patients. Complications were mostly attributed to concurrent drugs, especially other anesthetics. Mortality rate was 43% (26 of 60), but was lower when SE was controlled within 24 h of ketamine initiation (16% vs. 56%, p = 0.0047).

SIGNIFICANCE

Ketamine appears to be a relatively effective and safe drug for the treatment of RSE. This retrospective series provides preliminary data on effective dose and appropriate time of intervention to aid in the design of a prospective trial to further define the role of ketamine in the treatment of RSE.

Amygdala activation in maltreated children during pre-attentive emotional processing

BACKGROUND

Childhood adversity is associated with significantly increased risk of psychiatric disorder. To date, functional magnetic resonance imaging (fMRI) studies of children have mainly focused on institutionalisation and investigated conscious processing of affect.

AIMS

To investigate neural response to pre-attentively presented affect cues in a community sample of children with documented experiences of maltreatment in the home.

METHOD

A masked dot-probe paradigm involving pre-attentive presentation of angry, happy and neutral facial expressions was employed. Eighteen maltreated children were compared with 23 carefully matched non-maltreated peers.

RESULTS

Increased neural response was observed in the right amygdala for pre-attentively presented angry and happy faces in maltreated v. non-maltreated children. Level of amygdala activation was negatively associated with age at onset for several abuse subtypes.

CONCLUSIONS

Maltreatment is associated with heightened neural response to positive and negative facial affect, even to stimuli outside awareness. This may represent a latent neural risk factor for future psychiatric disorder.

Reflections on wisdom and self

The end of the year is often a time of reflection. For most of us, 2012 will have brought events that were planned, perhaps for years, as well as others that were full of serendipity or unexpected misfortune. We are invariably older than we were in January. We approach December with our own rituals: summer holidays, Hanukkah, Christmas or New Year's Eve. We may reflect on our joys and disappointments, or our actions and lessons learnt.

WITHDRAWN: Distraction osteogenesis using monolateral external fixator for post-traumatic skeletal defects of the femur

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Chemoresistant colorectal cancer cells and cancer stem cells mediate growth and survival of bystander cells

BACKGROUND

Recent studies suggest that cancer stem cells (CSCs) mediate chemoresistance, but interestingly, only a small percentage of cells in a resistant tumour are CSCs; this suggests that non-CSCs survive by other means. We hypothesised that chemoresistant colorectal cancer (CRC) cells generate soluble factors that enhance survival of chemonaive tumour cells.

METHODS

Chemoresistant CRC cells were generated by serial passage in oxaliplatin (Ox cells). Conditioned media (CM) was collected from parental and oxaliplatin-resistant (OxR) cells. CRC cells were treated with CM and growth and survival were assessed. Tumour growth rates were determined in nude mice after cells were treated with CM. Mass spectrometry (MS) identified proteins in CM. Reverse phase protein microarray assays determined signalling effects of CM in parental cells.

RESULTS

Oxaliplatin-resistant CM increased survival of chemo-naive cells. CSC CM also increased growth of parental cells. Parental and OxR mixed tumours grew larger than tumours composed of parental or OxR cells alone. Mass spectrometry detected unique survival-promoting factors in OxR CM compared with parental CM. Cells treated with OxR CM demonstrated early phosphorylation of EGFR and MEK1, with later upregulation of total Akt .We identified progranulin as a potential mediator of chemoresistance.

CONCLUSION

Chemoresistant tumour cells and CSCs may promote resistance through soluble factors that mediate survival in otherwise chemosensitive tumour cells.