Patient evaluation of outpatient venous thromboembolism prophylaxis service following lower limb injuries using a developed validated questionnaire.

This paper explores patients' perceptions of a new service and protocol for managing outpatient venous thromboembolism (VTE) prophylaxis, using either subcutaneous Dalteparin or oral off-license Dabigatran in patients with lower limb injury requiring immobilisation. Establishing a patient's perspective is part of good practice as, when this is positive, it aids patient compliance and protocol dissemination. A questionnaire consisting of fifty questions was given at random to one hundred patients over a six month period when they attended the trauma clinic. Each question was scored on a five point Likert scale (1 = poor, 5 = excellent) by the patient. The internal consistency of the questionnaire (Cronbach's alpha reliability coefficient) was more than 0.9 in all domains. Qualitative analysis was done for open-ended questions. One hundred respondents completed the questionnaire, two were void due to significant amounts of incomplete data. The gender split was 54 females, 43 males, and one did not answer the question. The average age was 43 (range 18-72). Sixty seven respondents were first-time attenders, 22 were follow-up patients and nine did not complete this section. The overall average score was 4.26 (range 1-5), with 90% of the patients recommending the service. The overall patient satisfaction for a VTE prophylaxis service is high although there is room for improvement as demonstrated by the range of the scores.

The impact of surgeon handedness in total hip replacement.

INTRODUCTION: Total hip replacement (THR) is successful and performed commonly. Component placement is a determinant of outcome. Influence of surgeon handedness on component placement has not been considered previously. This study was a radiographic assessment of component positioning with respect to handedness. Early data from 160 patients are reported. METHODS: Overall, 160 primary THRs for osteoarthritis were included. Equal numbers of left and right THRs were performed by four surgeons, two right-handed and two left-handed. Postoperative radiography was assessed for THR component position by measurement of leg length inequality, acetabular inclination and centre of rotation. Surgeons' handedness was assessed using the Edinburgh inventory. RESULTS: For leg length inequality, no significant interaction was seen between hip side and surgeon handedness. Acetabular inclination angles showed a statistically significant difference, however, depending on hand dominance, with higher inclination angles recorded when operating on the dominant side. There was a trend towards greater medialisation of the centre of rotation on the non-dominant side although this did not reach statistical significance. CONCLUSIONS: Surgeon handedness appears to influence acetabular component position during THR but it is one factor of many that interact to achieve a successful outcome.

Long-term outcome of deep brain stimulation in generalised dystonia: a series of 60 cases.

BACKGROUND: There is solid evidence of the long term efficacy of deep brain stimulation of the globus pallidus pars interna in the treatment of generalised dystonia. However there are conflicting reports concerning whether certain subgroups gain more benefit from treatment than others. We analysed the results of a series of 60 cases to evaluate the effects of previously proposed prognostic factors including dystonia aetiology, dystonia phenotype, age at onset of dystonia, and duration of dystonia prior to treatment. METHODS: 60 patients with medically intractable primary or secondary generalised dystonia were treated with deep brain stimulation of the globus pallidus pars interna during the period 1999-2010 at the Department of Neurosurgery in Oxford, UK. Patients were assessed using the Burke-Fahn-Marsden (BFM) Dystonia Rating Scale prior to surgery, 6 months after implantation and thereafter at 1 year, 2 years and 5 years follow-up. RESULTS: The group showed mean improvements in the BFM severity and disability scores of 43% and 27%, respectively, by 6 months, and this was sustained. The results in 11 patients with DYT gene mutations were significantly better than in non-genetic primary cases. The results in 12 patients with secondary dystonia were not as good as those seen in non-genetic primary cases but there remained a significant beneficial effect. Age of onset of dystonia, duration of disease prior to surgery, and myoclonic versus torsional disease phenotype had no significant effect on outcome. CONCLUSIONS: The aetiology of dystonia was the sole factor predicting a better or poorer outcome from globus pallidus pars interna stimulation in this series of patients with generalised dystonia. However even the secondary cases that responded the least well had a substantial reduction in BFM scores compared with preoperative clinical assessments, and these patients should still be considered for deep brain stimulation.

Deep brain stimulation for tremor resulting from acquired brain injury.

OBJECTIVES: To evaluate the efficacy of deep brain stimulation (DBS) in the treatment of tremor resulting from acquired brain injury (ABI). METHODS: A series of eight consecutive patients with post-ABI tremor were treated with DBS of the ventro-oralis posterior (VOP)/zona incerta (ZI) region, and subsequently underwent blinded assessments using Bain's tremor severity scale. RESULTS: VOP/ZI DBS produced a mean reduction in tremor severity of 80.75% based on Bain's tremor severity scale, with significant reductions in all five component tremor subscores: rest, postural, kinetic, proximal and distal. No adverse neurological complications were reported, although one patient experienced exacerbation of pre-existing gait ataxia. CONCLUSION: VOP/ZI stimulation is demonstrated here to be an effective and safe approach for the treatment of post-ABI tremor in the largest series published at the time of writing.

The cost of outpatient venous thromboembolism prophylaxis following lower limb injuries.

This paper reports the cost of outpatient venous thromboembolism (VTE) prophylaxis following 388 injuries of the lower limb requiring immobilisation in our institution, from a total of 7408 new patients presenting between May and November 2011. Prophylaxis was by either self-administered subcutaneous dalteparin (n = 128) or oral dabigatran (n = 260). The mean duration of prophylaxis per patient was 46 days (6 to 168). The total cost (pay and non-pay) for prophylaxis with dalteparin was £107.54 and with dabigatran was £143.99. However, five patients in the dalteparin group required nurse administration (£23 per home visit), increasing the cost of dalteparin to £1142.54 per patient. The annual cost of VTE prophylaxis in a busy trauma clinic treating 12 700 new patients (2010/11), would be £92 526.33 in the context of an income for trauma of £1.82 million, which represents 5.3% of the outpatient tariff. Outpatient prophylaxis in a busy trauma clinic is achievable and affordable in the context of the clinical and financial risks involved.

Diagnostic and prognostic markers in gliomas - an update.

Gliomas are the most common primary central nervous system tumour seen in adults. There have been many advances over the last two decades as we widen our search for a molecular basis of gliomagenesis. Many biomarkers have been discovered to be important in the management of gliomas, including 1p19q co-deletion, MGMT promoter methylation, BRAF and IDH1 mutations. In this review, we attempt to summarise the available literature on these biomarkers and their use in the diagnosis and management of gliomas. We pay special attention to the recently discovered IDH1 mutation, which is already proving to be a valuable new marker for favourable prognosis and may also indicate a greater response to therapy. 1p19q co-deletions have been shown to delineate a clinically distinct tumour type and are now routinely tested for in certain situations and can help direct treatment. MGMT promoter methylation is one of the most commonly studied biomarkers in gliomas. It has been shown to be a strong positive prognostic marker in gliomas, with positive tumours being more sensitive to chemotherapy. However, a lack of alternatives means that it is not yet a routine mutation tested for clinically. BRAF mutations are new markers found in pilocytic astrocytomas. Although the prognostic value of such mutations is not yet known, they may play a significant role in the diagnosis and treatment of such tumours. IDH1 mutations are 'the new kid on the block' and seem to play a central role in the pathogenesis of gliomas. They represent an independent and favourable prognostic marker and are a new molecular marker for disease diagnosis. Its role in determining response to chemotherapy is still controversial but with further study, IDH1 mutations may prove to be an invaluable marker in the management of gliomas.

A national survey of acute hospitals in England on their current practice in the use of femoral nerve blocks when splinting femoral fractures.

INTRODUCTION: Missed compartment syndrome can have devastating long-term impact on a patient's function. Femoral fracture has been reported in 52-58% of acute thigh compartment syndromes in the existing literature. Time to diagnosis of compartment syndrome is cited as a key determinant of outcome. Use of femoral nerve blocks in splinting of femoral fractures may mask signs of early compartment syndrome. We present the attitudes of emergency department and orthopaedic staff in NHS trusts in England with regard to this issue. METHODS AND MATERIALS: Survey of all 171 acute hospitals in the United Kingdom accepting trauma admissions. On-call middle grade doctors in emergency and orthopaedic department completed a telephone survey into departmental protocol and their experience of femoral nerve blocks for lower limb fractures. RESULTS: Middle grades from all 171 trusts completed the survey (100% response rate). 54 emergency departments (30.8%) had a protocol for the use of femoral nerve blocks. Middle grades in the ED reported using a nerve block routinely in 95 hospitals (54%) with 63 using a long-acting and 32 a short-acting agent. Of those that did not 70% (n=53) felt they were unnecessary, 21% (n=16) were not confident in the technique and 9% (n=7) had worries over compartment syndrome. 68% would be worried about compartment syndrome in high-energy injuries. Orthopaedic departmental protocols for nerve block use were reported in 16 trusts (9%). 45 orthopaedic middle grades (26%) indicated that they would use them routinely with 17 using long-acting and 28 using short-acting agents. 59.5% (n=75) of orthopaedic middle grades felt nerve blocks were unnecessary, whilst 22% (n=28) had worries about compartment syndrome and 18% (n=23) were not confident with the technique. 77% orthopaedic middle grades would be more worried about compartment syndrome in high energy injuries. CONCLUSION: Femoral nerve block is an under-utilised, effective mode of analgesia following femoral fractures. There is a low risk of associated compartment syndrome, but clinicians should be especially vigilant in high-energy injuries. We recommend that all acute trusts receiving trauma should have a protocol for the use of femoral nerve blocks agreed by the emergency and orthopaedic departments.

Deep brain stimulation of the pedunculopontine nucleus in Parkinson's disease. Preliminary experience at Oxford.

Deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) is a novel neurosurgical therapy developed to address symptoms of gait freezing and postural instability in Parkinson's disease and related disorders. Here, we summarize our non-human primate and neuroimaging research of relevance to our surgical targeting of the PPN. We also describe our clinical experience of PPN DBS with greatest motor improvements achieved by stimulation at low frequencies.

Proposals for the management of gastrointestinal stromal tumours of the stomach.

BACKGROUND AND AIMS: It has been reported that gastric gastrointestinal stromal tumours (GIST) are aggressive, rare and difficult to treat. Some have advocated radical resection as the only potential cure. We present data to support treatment of gastric GISTs with a limited surgical approach and minimal morbidity. Furthermore, we propose that surveillance for recurrence is unnecessary based upon the follow-up of a cohort of patients with gastric GISTs. METHODS: Database and case notes analysis of 20 patients diagnosed with gastric GIST (1998-2004) and managed by one surgeon in a single centre over seven years. Main outcome measures were inpatient adverse events, positive resection margins and symptom free survival. OUTCOMES: Three cases have been managed with surveillance only. Successful resection was performed in 17 patients without mortality. No patient had positive margins on histological assessment. Fifteen out of seventeen samples were positive for the c-Kit proto-oncogene (CD117) and 14117 positive for CD34. Only two patients required en-bloc resections due to the tumour size and involvement of adjacent structures. One patient developed metastatic disease during follow-up of 19-86 months. CONCLUSIONS: We recommend local excision of gastric GISTs to allow macroscopically clear margins. This policy then allows symptomatic follow-up due to the indolent nature of the majority of the tumours resected. A tailored follow-up with endoscopy and radiological imaging has been advocated by others but appears unnecessary in most cases. Imatinib (anti c-Kit) can now be offered to patients presenting with recurrent GIST, if further surgery is deemed inappropriate.

Using magnetoencephalography to investigate brain activity during high frequency deep brain stimulation in a cluster headache patient.

PURPOSE: Treatment-resistant cluster headache can be successfully alleviated with deep brain stimulation (DBS) of the posterior hypothalamus [1]. Magnetoencephalography (MEG) is a non-invasive functional imaging technique with both high temporal and high spatial resolution. However, it is not known whether the inherent electromagnetic (EM) noise produced by high frequency DBS is compatible with MEG. MATERIALS AND METHODS: We used MEG to record brain activity in an asymptomatic cluster headache patient with a DBS implanted in the right posterior hypothalamus while he made small movements during periods of no stimulation, 7 Hz stimulation and 180 Hz stimulation. RESULTS: We were able to measure brain activity successfully both during low and high frequency stimulation. Analysis of the MEG recordings showed similar activation in motor areas in during the patient's movements as expected. We also observed similar activations in cortical and subcortical areas that have previously been reported to be associated with pain when the patient's stimulator was turned on or off [2,3]. CONCLUSION: These results show that MEG can be used to measure brain activity regardless of the presence of high frequency deep brain stimulation.

Dose-related effect of sevoflurane sedation on higher control of eye movements and decision making.

BACKGROUND: Saccadic latency may provide an objective method to assess sedative doses of anaesthetic on cortical oculomotor mechanisms and decision making. METHODS: We tested the effects of random doses of 0, 0.1, 0.2 and 0.3 MAC sevoflurane in six subjects, in a double-blind study using two measures of behavioural impairment: saccadic latency and stop signal reaction time (SSRT) in a countermanding task. RESULTS: Saccadic latency and SSRT both increased with increasing doses of sevoflurane. In both measures, reciprocal reaction time was linearly related to dose in each subject: all but two of the twelve regression coefficients were statistically significant (P<0.05). In one subject, SSRT was significantly more sensitive than simple latency (P<0.05); for the others there was no significant difference. CONCLUSION: Measurements of this kind could potentially provide estimates of cortical effects of sevoflurane sedation, and give a clinically useful measure of cognitive fitness.

Memory and judgment: availability versus explanation-based accounts.

Two theories about the relationship between memory and decisions are examined. In an explanation-based model, the organization in memory of decision-relevant information determines decisions. In an availability model, the amount of information sampled from memory that supports competing decisions is crucial. In Experiment 1, subjects read evidence from a legal trial, made decisions, and provided free-recall data. Evidence presentation order was manipulated to produce differences in evidence coherence. When the prosecution evidence order was coherent, the subjects were more likely to choose guilty verdicts, and recall of prosecution evidence, relative to defense evidence, was greater. Thus, both evidence coherence and availability of information in memory could account for the basic findings. In Experiment 2, recall differences were eliminated as a function of evidence order. The results show that verdict effects favoring the more coherent prosecution evidence are obtained even when the relative amounts of prosecution and defense recall are equated across conditions.

Reasoning in explanation-based decision making.

A general theory of explanation-based decision making is outlined and the multiple roles of inference processes in the theory are indicated. A typology of formal and informal inference forms, originally proposed by Collins (1978a, 1978b), is introduced as an appropriate framework to represent inferences that occur in the overarching explanation-based process. Results from the analysis of verbal reports of decision processes are presented to demonstrate the centrality and systematic character of reasoning in a representative legal decision-making task.

Preliminary assessment of the acute toxicity of malathion in animals.

Laboratory studies were conducted to acquire information concerning the acute toxicity of malathion in animals under various conditions of exposure. The responses in rabbits and quail exposed to aerosols generated from technical grade malathion (95%) and approximating an ultra-low volume ground spray were compared with those from a 6% malathion/No. 2 fuel oil mixture simulating a high volume spray. Results indicate that technical grade malathion (95%) as an ultra-low volume spray and at effective insecticidal concentrations in particle sizes having a mass median diameter of about 12 mu is relatively nonhazardous compared to the possible toxic fuel oil effects of a 6% malathion/No. 2 fuel oil mixture with a mass median diameter of 25 mu. Based on blood plasma cholinesterase activity analyses, quail were more sensitive to equivalent malathion exposure concentrations than were rabbits. Oral administration of technical grade malathion to rabbits resulted in reduction of plasma and erythrocyte cholinesterase activity at dosages of 120, 300, and 600 mg/kg with death resulting from 1200 mg/kg.

Diatom diversity as a function of insecticidal treatment with a controlled-release formulation of chlorpyrifos.

Following treatment with a controlled-release formulation of chlorpyrifos, no substantial differences between diversity estimates were evident for 6 post-treatment weeks for both treated and control plots. By post-treatment week 12, significant decreases in diversity estimates occurred in treated plots, suggesting that a directly proportional relationship exists between chlorpyrifos concentrations and reduced diatom colonization through time. Comparatively, diatom colonization progress "normally" and populations proceeded toward "maturity" in the control plots as indicated by the increase in the diversity estimates between post-treatment weeks 6 and 12. Any adverse effects due to the insecticidal treatment, however, were not considered to be environmentally deleterious in light of the restricted type of habitat (rice culture) in which the chlorpyrifos was used.