A second chance for a new heart? The role of metabolic and bariatric surgery in patients with end-stage heart failure

BACKGROUND

Obesity is an independent risk factor for heart failure (HF). Substantial weight loss has been shown to reverse obesity-related cardiomyopathy. This study aimed to report our institution's experience with laparoscopic sleeve gastrectomy (LSG) in patients with morbid obesity and end-stage HF.

METHODS

Between 2018 and 2022, 26 patients with end-stage HF were referred for LSG. Of 26 patients, 16 underwent an operation, and 10 did not. After institutional review board approval, a retrospective electronic medical record review was performed to evaluate (i) age, (ii) preoperative weight, (iii) decrease in body mass index (BMI) score, (iv) whether the patient underwent heart transplantation, and (v) mortality. Data analysis was performed using Stata/SE (version 17.0; StataCorp). The Wilcoxon rank-sum test was used to compare continuous variables between the cohorts, and the Pearson chi-square test was used for binary variables with Bonferroni correction applied.

RESULTS

The LSG and non-LSG cohorts had comparable ages (P = .088) and starting BMI score (P = .918), and a proportion of patients had a ventricular assist device (P = .191). Patients who underwent LSG lost significantly more weight than the patients who did not, with an average decrease in BMI score of 8.9 kg/m2 (SD, ±6.13) and 1.1 kg/m2 (SD, ±4.10), respectively (P = .040). Of note, 6 patients (37.5%) who underwent LSG eventually underwent transplantation, compared with 2 patients (20.0%) from the matched cohort (P = .884). Of the 26 patients, there were 6 deaths: 2 (12.5%) in the LSG cohort and 4 (40.0%) in the non-LSG cohort (P = .525).

CONCLUSION

LSG may be safe and effective for weight loss in patients with HF. This operation may provide patients affected by obesity with end-stage HF the lifesaving opportunity to achieve transplant candidacy.

An open-source platform for pediatric cancer data exploration: a report from Data for the Common Good

Objective

The Pediatric Cancer Data Commons (PCDC)-a project of Data for the Common Good-houses clinical pediatric oncology data and utilizes the open-source Gen3 platform. To meet the needs of end users, the PCDC development team expanded the out-of-box functionality and developed additional custom features that should be useful to any group developing similar data commons.

Materials and Methods

Modifications of the PCDC data portal software were implemented to facilitate desired functionality.

Results

Newly developed functionality includes updates to authorization methods, expansion of filtering capabilities, and addition of data analysis functions.

Discussion

We describe the process by which custom functionalities were developed. Features are open source and available to be implemented and adapted to suit needs of data portals that utilize the Gen3 platform.

Conclusion

Data portals are indispensable tools for facilitating data sharing. Open-source infrastructure facilitates a modular and collaborative approach for meeting needs of end users and stakeholders.

Fixed-Bearing Unicompartmental Knee Arthroplasty of the Lateral Compartment: A Series of 246 Cases

Background

Isolated osteoarthritis of the lateral compartment of the knee is less common than that of the medial compartment, resulting in significantly fewer lateral unicompartmental knee arthroplasties (UKAs) being performed. This study aimed to evaluate results of a fixed-bearing UKA for the treatment of lateral compartment osteoarthritis of the knee.

Methods

A prospectively collected cohort of 255 patients undergoing fixed-bearing UKA of the lateral compartment using the Triathlon PKR (Stryker, Warsaw, IND) implant with a minimum 2-year follow-up was reviewed. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, radiographic alignment, complications, reoperations, and revisions were recorded. Patient factors and pre- and post-surgical alignment were assessed for their association with a minimum important change (MIC) of the total WOMAC score.

Results

A total of 246 implants with a mean follow-up of 6.6 years (2-10.8 years) were included (4% lost to follow-up). The total WOMAC score increased from 61.3 ± 3.5 to 85.3 ± 7.5, exceeding the MIC in 215 patients (88%). Exceeding the MIC was not associated with age, body mass index, or alignment. The 5-year implant revision rate was 1.6% (3/187).

Conclusions

The fixed-bearing Stryker Triathlon PKR implant for lateral UKA resulted in good clinical outcomes with a low revision rate at midterm follow-up. Body mass index, age, and pre- and post-surgical alignment did not correlate with the clinical outcome. Long-term follow-up is necessary to determine if the clinical improvement and low revision rate can be maintained.

Intracardiac thrombosis and pulmonary thromboembolism during liver transplantation: A systematic review and meta-analysis

Intracardiac thrombosis and/or pulmonary thromboembolism (ICT/PE) is a rare but devastating complication during liver transplantation. Its pathophysiology remains poorly understood, and successful treatment remains a challenge. This systematic review summarizes the available published clinical data regarding ICT/PE during liver transplantation. Databases were searched for all publications reporting on ICT/PE during liver transplantation. Data collected included its incidence, patient characteristics, the timing of diagnosis, treatment strategies, and patient outcomes. This review included 59 full-text citations. The point prevalence of ICT/PE was 1.42%. Thrombi were most often diagnosed during the neohepatic phase, particularly at allograft reperfusion. Intravenous heparin was effective in preventing early-stage thrombus from progressing further and restoring hemodynamics in 76.32% of patients it was utilized for; however, the addition of tissue plasminogen activator or sole use of tissue plasminogen activator offered diminishing returns. Despite all resuscitation efforts, the in-hospital mortality rate of an intraoperative ICT/PE was 40.42%, with nearly half of these patients dying intraoperatively. The results of our systematic review are an initial step for providing clinicians with data that can help identify higher-risk patients. The clinical implications of our results warrant the development of identification and management strategies for the timely and effective treatment of these tragic occurrences during liver transplantation.

Does capsular distension and a short period of countertraction improve outcome following manipulation under anesthesia for the treatment of primary adhesive capsulitis of the glenohumeral joint?

BACKGROUND

Despite the fact that primary adhesive capsulitis of the glenohumeral joint is often considered a self-limiting condition, not all patients make a full recovery. Manipulation under anesthesia (MUA) is performed to forcibly rupture the contracted capsule in a controlled manner. However, the technique, timing, and use of additional injections are often debated. In this study, we report the outcomes following the addition of capsular distension and countertraction to MUA as a treatment for adhesive capsulitis.

METHODS

We performed a retrospective case-cohort study comparing 3 groups: Group 1 underwent MUA alone (n = 54); group 2, MUA with capsular distension (n = 114); and group 3, MUA with capsular distension and countertraction (n = 167). The re-MUA rate, Constant-Murley shoulder (CMS) score, and visual analog scale (VAS) score (for pain) were measured after 6 weeks and 6 months.

RESULTS

The re-MUA rate fell with the addition of both capsular distension and countertraction: 63% in group 1, 39% in group 2, and 18% in group 3. Patients in group 3 recorded the greatest improvement in the CMS score after 6 weeks (+90% vs. +68% in group 2 and +58% in group 1), with all groups showing improvements compared with before treatment. The only independent risk factor identified for re-MUA was smoking. If a second MUA was performed, the CMS (+67%) and VAS (+61%) scores improved, but at 6 months, the CMS score (74.57 ± 7.6 vs. 83.30 ± 5.5) and VAS score (10.57 ± 1.8 vs. 12.96 ± 1.5) remained inferior to those of patients who only needed a single MUA.

DISCUSSION AND CONCLUSION

MUA combined with capsular distension and countertraction reduces the need for a second MUA and results in a faster improvement in functional outcome (CMS score) and reduction of pain (VAS score) compared with MUA alone or MUA with capsular distension. The results of this case-cohort study are of clinical relevance because they show that the efficacy of an MUA can be improved through relatively simple adaptations of the treatment protocol.

Peritonsillar Abscess at a Dedicated Otolaryngology Emergency Department

Aim Peritonsillar abscess (PTA) is the most common suppurative complication of acute tonsillitis. It requires urgent specialist treatment due to the risk of progression to airway compromise. We aimed to review referral pathways to a dedicated otolaryngology emergency department (ORL-ED), identify causative organisms and discuss COVID-19 implications. Methods A retrospective review of patients presenting to the ORL-ED between January 2018 and December 2019 was undertaken. Data extracted included demographics, referral source, treatment, microbiology results and length of stay. Statistical analysis of seasonal variation of presentation and causative organisms employed Chi-Square and Fisher's Exact Test, respectively. Results There were 53 PTA presentations. 51 were admitted accounting for 44.3% (51/115) of ED admissions. The median patient age was 31 years (IQR 20-40yrs). GP referral accounted for 48/53 (90.6%). There was no statistically significant seasonality (χ2=5.94, p=0.11) in presentation. Microbiology samples were available for 44 patients. Streptococcus was identified in 19/44 (43.2%) patients. 85% (45/53) of patients received Co-amoxiclav. Discussion PTA is a perennial condition with diverse causative organisms. Antibiotic choice should reflect this. The majority of patients are referred from primary care, emphasising the role of the GP in initial diagnosis and the importance of clinical education in this regard.

Outcome of High-power Short-duration Radiofrequency Ablation in Combination with Half-Normal Saline Irrigation for the Treatment of Atrial Fibrillation

BACKGROUND

Data regarding the use of high-power short-duration (HPSD) radiofrequency (RF) in combination with half-normal saline irrigation for catheter irrigation is limited.

OBJECTIVES

This study investigated the safety and efficacy of using HPSD RF ablation in combination with half-normal saline irrigation for the treatment of AF.

METHODS

 One hundred consecutive patients with AF underwent RF ablation using HPSD combined with half-normal saline for catheter irrigation. In addition, the following ablation strategies were used: 1 mm tags for the display of ablation lesions on the mapping system, high-frequency jet ventilation (HFJV), low contact force, pacing after ablation to verify areas of noncapture, atrial/ventricular pacing at 500 to 700 ms to aid in catheter stability, use of two skin electrodes to reduce impedance, and post-ablation adenosine infusion. Power was started at 40-45 W and was modulated manually based on impedance changes.

RESULTS

 The average age of patients was 65.2 years and 70% were male. Forty-seven percent had paroxysmal AF and the average CHA₂ DS₂ -VASc score was 2.1±1.6. The average power and lesion duration were 38.1 ± 3.3 W and 8.1 ± 2.3 seconds, respectively. During a median follow-up period of 321 ± 139 days, 89% of the patients remained free from any atrial arrhythmias after a single RF ablation procedure. No procedure-related death, stroke, pericardial effusion, or atrioesophageal fistula occurred during follow-up.

CONCLUSIONS

 Catheter ablation using HPSD RF lesions in combination with half-normal saline irrigation and is safe and effective, and results in high rate of freedom from AF. This article is protected by copyright. All rights reserved.

Linked Entity Attribute Pair (LEAP): A Harmonization Framework for Data Pooling

PURPOSE

As data-sharing projects become increasingly frequent, so does the need to map data elements between multiple classification systems. A generic, robust, shareable architecture will result in increased efficiency and transparency of the mapping process, while upholding the integrity of the data.

MATERIALS AND METHODS

The American Association for Cancer Research’s Genomics Evidence Neoplasia Information Exchange (GENIE) collects clinical and genomic data for precision cancer medicine. As part of its commitment to open science, GENIE has partnered with the National Cancer Institute’s Genomic Data Commons (GDC) as a secondary repository. After initial efforts to submit data from GENIE to GDC failed, we realized the need for a solution to allow for the iterative mapping of data elements between dynamic classification systems. We developed the Linked Entity Attribute Pair (LEAP) database framework to store and manage the term mappings used to submit data from GENIE to GDC.

RESULTS

After creating and populating the LEAP framework, we identified 195 mappings from GENIE to GDC requiring remediation and observed a 28% reduction in effort to resolve these issues, as well as a reduction in inadvertent errors. These results led to a decrease in the time to map between OncoTree, the cancer type ontology used by GENIE, and International Classification of Disease for Oncology, 3rd Edition, used by GDC, from several months to less than 1 week.

CONCLUSION

The LEAP framework provides a streamlined mapping process among various classification systems and allows for reusability so that efforts to create or adjust mappings are straightforward. The ability of the framework to track changes over time streamlines the process to map data elements across various dynamic classification systems.

The Veterans Precision Oncology Data Commons: Transforming VA data into a national resource for research in precision oncology

The Department of Veterans Affairs (VA) has a strong track record providing high-quality, evidence-based care to cancer patients. In order to accelerate discoveries that will further improve care for Veterans with cancer, the VA has partnered with the Center for Translational Data Science at the University of Chicago and the Open Commons Consortium to establish a data sharing platform, the Veterans Precision Oncology Data Commons (VPODC). The VPODC makes clinical, genomic, and imaging data from the VA available to the research community at large. In this paper, we detail our motivation for data sharing, describe the VPODC, and outline our collaboration model. By transforming VA data into a national resource for research in precision oncology, the VPODC seeks to foster innovation through collaboration and resource sharing that will ultimately lead to improved care for Veterans with cancer.

Machine Learning Methods to Predict Lung Cancer Survival Using the Veterans Affairs Research Precision Oncology Data Commons

We completed a pilot study to guide the development of the VA Research Precision Oncology Data Commons infrastructure as a collaboration platform with the greater research community. Our results using a small subset of patients from the VA's Precision Oncology Program demonstrate the feasibility of our data sharing platform to build predictive models for lung cancer survival using machine learning, as well as highlight the potential of target genome sequencing data.

Harmonization of clinical data across Gen3 data commons

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Background: Gen3 is an open source software platform for developing and operating data commons. Gen3 systems are now used by a variety of institutions and agencies to share and analyze large biomedical datasets including clinical and genomic data. One of the challenges of working with these datasets is disparate clinical data standards used by researchers across different studies and fields. We have worked to address these hurdles in a variety of ways. Methods: Gen3 is an open source software platform for developing and operating data commons. Detailed specification and features can be found at https://gen3.org/ with code located on GitHub ( https://github.com/UC-cdis ). Results: The Gen3 data model is a graphical representation of the different nodes or classes of data that have been collected. Examples include diagnosis, demographic, exposure, and family history. The properties and values on each node are controlled by the data dictionary specified by the data commons creator. While each commons may have a unique data model and dictionary, specifying external standards allows for easier submission of new data and assists data consumers with interpretation of results. A variety of external references can be supported, but here we demonstrate the use of the National Cancer Institute Thesaurus (NCIt). NCIt provides reference terminologies and biomedical standards that contain a rich set of terms, codes, definitions, and concepts. Using the same reference standards across commons allows for the export of clinical data between commons. The Portable Format for Biomedical Data (PFB) was created to facilitate data export and to allow the data dictionary schema as well as the raw data to be compressed and exported. This new file format, which utilizes an Avro serialization, is small, fast, easy to modify, and enables simple data export and import. PFB also has the ability to house entire external reference ontologies and it is easy to update the PFB references as changes are introduced. Conclusions: We have shown here how the Gen3 data model, use of external reference standards for clinical data, and the export/import format of PFB enable the harmonization of clinical data across different data commons.

Management of Pulmonary Hemorrhage Complicating Pulmonary Thromboendarterectomy

Airway management during pulmonary thromboendarterectomy (PTE) can prove challenging, especially in the face of unexpected intraoperative pulmonary hemorrhage. Utilization of proper airway equipment on induction is crucial for the successful management of intraoperative pulmonary hemorrhage. Our case series describes the preoperative risk factors that can lead to intraoperative pulmonary hemorrhage, the preinduction airway equipment considerations for PTE, and the intraoperative management of pulmonary hemorrhage. We summarize the lessons learned at our institution from four cases of post perfusion pulmonary hemorrhage.

Developing Cancer Informatics Applications and Tools Using the NCI Genomic Data Commons API

The NCI Genomic Data Commons (GDC) was launched in 2016 and makes available over 4 petabytes (PB) of cancer genomic and associated clinical data to the research community. This dataset continues to grow and currently includes over 14,500 patients. The GDC is an example of a biomedical data commons, which collocates biomedical data with storage and computing infrastructure and commonly used web services, software applications, and tools to create a secure, interoperable, and extensible resource for researchers. The GDC is (i) a data repository for downloading data that have been submitted to it, and also a system that (ii) applies a common set of bioinformatics pipelines to submitted data; (iii) reanalyzes existing data when new pipelines are developed; and (iv) allows users to build their own applications and systems that interoperate with the GDC using the GDC Application Programming Interface (API). We describe the GDC API and how it has been used both by the GDC itself and by third parties. Cancer Res; 77(21); e15-18. ©2017 AACR.

Collaborating to Compete: Blood Profiling Atlas in Cancer (BloodPAC) Consortium

The cancer community understands the value of blood profiling measurements in assessing and monitoring cancer. We describe an effort among academic, government, biotechnology, diagnostic, and pharmaceutical companies called the Blood Profiling Atlas in Cancer (BloodPAC) Project. BloodPAC will aggregate, make freely available, and harmonize for further analyses, raw datasets, relevant associated clinical data (e.g., clinical diagnosis, treatment history, and outcomes), and sample preparation and handling protocols to accelerate the development of blood profiling assays.

Perampanel: An audit of clinical experience using the epilepsy electronic patient record

Perampanel is a non-competitive antagonist of AMPA glutamate receptors on post synaptic neurons. The aim of this study was to conduct an audit of the experience of perampanel treatment in Ireland based on the interrogation of the national epilepsy electronic patient record (EPR). A retrospective audit was compiled which reviewed the progress of patients who had been treated across two regional epilepsy centres. The EPR was used to identify patients and collect information relevant to their perampanel therapy. Collected data was entered into a statistical package for social sciences for analysis using descriptive statistics. Seventy patients were identified for inclusion in this audit. Partial onset epilepsy was the predominant epilepsy syndrome treated with perampanel. Eight milligrams daily was the maximum dose achieved in 31.45% (n=22). Complex partial seizures demonstrated the best seizure response to perampanel, which was optimal at doses of 4mgs to 8mgs once daily. Treatment was discontinued primarily due to side effect profile (28.5%; n=20). The common side effects reported were behavioural alteration, sedation and dizziness. Abnormal thoughts were identified in 4.2% (n=3). Overall perampanel has been shown to be an effective adjunct. The EPR was demonstrated as an effective tool for audit and research.

Towards the development of integrated epilepsy services: an audit of documented epilepsy care

Effective chronic disease management (CDM) requires the ready availability and communication of accurate, clinical disease specific information. Using epilepsy as a probe into CDM, we report on the availability and reliability of clinical information in the primary care records of people with epilepsy (PWE). The medical records of 374 PWE from 53 general practices in the Mid-West region of Ireland were examined. Confirmation of an epilepsy diagnosis by a neurologist was documented for 132 (35%) patients. 282 (75%) patients had no documented evidence of receiving specialist neurology review while 149 (40%) had not been reviewed by their GP in the previous two years for their epilepsy. Significant variation in documentation of epilepsy specific information together with an inadequacy and inconsistency of existing epilepsy services was highlighted.

A survey of reimbursement practices of private health insurance companies for pharmaceuticals not covered under the Pharmaceutical Benefits Scheme 2008

OBJECTIVE

To describe the current practices and policy of Australian private health insurance (PHI) companies with respect to cover for pharmaceuticals not subsidised under the Pharmaceutical Benefits Scheme (PBS).

DESIGN, SETTING AND PARTICIPANTS

A 2008 review of web-published policy statements for top-level hospital and comprehensive general treatment insurance, and survey of reimbursement practices by way of questionnaire, of 31 Australian-registered, open-membership PHI companies.

MAIN OUTCOME MEASURES(S)

Description of the level of pharmaceutical cover and important considerations identified by PHI companies for funding non-PBS pharmaceuticals through benefit entitlements or ex-gratia payments.

RESULTS

Nine of thirty-one PHI companies (29%) provided responses accounting for ~60% market share of PHI. The majority of smaller PHI firms either declined participation or did not respond. The maximum limits offered for non-PBS pharmaceuticals, under comprehensive general treatment insurance, varied significantly and typically did not adequately cover high-cost pharmaceuticals. Some companies occasionally offered ex-gratia payments (or discretionary payments in excess of the policyholder's entitlement benefits) for high cost-pharmaceuticals. Factors considered important in their decision to approve or reject ex-gratia requests were provided. All results were de-identified.

CONCLUSIONS

There is little consistency across PHI companies in the manner in which they handle requests for high-cost pharmaceuticals in excess of the defined benefit limits. Such information and processes are not transparent to consumers.

The health care journeys experienced by people with epilepsy in Ireland: what are the implications for future service reform and development?

Opportunities exist to significantly improve the quality and efficiency of epilepsy care in Ireland. Historically, epilepsy research has focused on quantitative methodologies that often fail to capture the invaluable insight of patient experiences as they negotiate their health care needs. Using a phenomenological approach, we conducted one-to-one interviews with people with epilepsy, reporting on their understanding of their health care journey from onset of symptoms through to their first interaction with specialist epilepsy services. Following analysis of the data, five major themes emerged: delayed access to specialist epilepsy review; uncertainty regarding the competency and function of primary care services; significant unmet needs for female patients with epilepsy; disorganization of existing epilepsy services; and unmet patient information needs. The findings reveal important insights into the challenges experienced by people with epilepsy in Ireland and identify the opportunities for future service reorganization to improve the quality and efficiency of care provided.

Epilepsy care in general practice

Epilepsy care in Ireland is shared between primary, secondary and tertiary care services with the General Practitioner (GP) managing the process. Barriers to effective epilepsy care in Irish general practice remain undocumented although sub-optimal and fragmented services are frequently anecdotally reported. This survey of Irish GPs reports on such barriers to epilepsy care and on the Information & Communication Technology (ICT) issues potentially relevant to the use of an epilepsy specific Electronic Patient Record (EPR). The response rate was 247/700 (35.3%). Respondents supported the concept of shared care for epilepsy 237 (96%) however they were very dissatisfied with existing neurology services, including pathways of referral 207 (84%) and access to specialist neurology advice and investigations 232 (94%). They reported that neurology services and investigations may be accessed more expeditiously by patients with private health insurance than those without 178 (72%). Consequently many patients are referred to the emergency department for assessment and treatment 180 (73%). A deficit in epilepsy care expertise among GPs was acknowledged 86 (35%). While computerisation of GP practices appears widespread 230 (93%), just over half the respondents utilise available electronic functionalities specific to chronic disease management. GP specific electronic systems infrequently link or communicate with external electronic sources 133 (54%). While the current pathways of care for epilepsy in Ireland appear fragmented and inadequate, further investigations to determine the quality and cost effectiveness of the current service are required.

Reliability of a repeated-sprint test for field-hockey

The purpose of this study was to assess the reliability of a repeated-sprint test, specifically designed for field-hockey, as it was based directly on the time-motion analysis of elite level competition. The test consisted of 6 x 30-m over-ground sprints departing on 25s, with an active recovery (approximately 3.1-3.3 ms(-1)) between sprints. Ten highly trained, male, field-hockey players (mean+/-S.D.: age, 23+/-3 years; body mass, 78.1+/-7.1 kg) participated in this study. Following familiarisation, the subjects performed the repeated-sprint test on two occasions, 7 days apart. The reliability of the test variables was assessed by the typical error of measurement (TE). The total sprint time was very reliable (T(1): 26.79+/-0.76 s versus T2: 26.83+/-0.74 s), as the TE was 0.7% (95% CL, 0.5-1.2%). However, the percent sprint decrement was less reliable (T1: 5.6+/-0.9% versus T2: 5.8+/-1.0%), with the TE being 14.9% (95% CL, 10.8-31.3%). In summary, it is suggested that this field-hockey-specific, repeated-sprint test is very reliable when the results are presented as the total sprint time.

Customer needs, expectations, and satisfaction with clinical neurophysiology services in Ireland: a case for tele-neurophysiology development

Although equitable access to services should be based on need, geographical location of patients and their clinicians can give rise to inequalities in healthcare delivery. Development of tele-medicine services can improve equity of access. The specialty of Clinical Neurophysiology (CN), currently under-developed in Ireland provides an example of such potential. This study aimed to determine the needs, expectations, and satisfaction of CN customers, namely patients and referring clinicians. The goal was to examine geographical impediments to access that might be addressed by the introduction of tele-neurophysiology. Two customer surveys were conducted: CN referring clinicians and CN patients. Thirty-one North Western Health Board (NWHB) consultant clinicians responded to a postal survey. Distance and delays caused by long waiting lists were felt to deter or make CN referral irrelevant. Ninety-seven percent believed the lack of a local service negatively impacts on patient management and 93% would welcome the introduction of a tele-neurophysiology service. The geographical location of patient's residence and/or the location of the referring clinician's practice influenced waiting lists for CN. Fifty-eight (105/182) percent of patients living in a region with a CN service compared to 39% (50/128) of those living in a region with no service received an appointment within one month. In addition to the current insufficient CN service capacity in Ireland, these surveys highlighted geographical inequities. Tele-neurophysiology has the potential to speed-up diagnosis, result in more patients being appropriately investigated and be fairer to patients.

Needs analysis for tele-neurophysiology in the Irish North-Western Health Board

No clinical neurophysiology (CN) service is currently provided by the North-Western Health Board (NWHB) region in Ireland. Digital technology associated with CN is compatible with tele-neurophysiology service development and may increase the efficiency of patient care in remote areas. This study was conducted to assess the need for CN in the NWHB with a view to implementing a tele-neurophysiology service for the region. A retrospective audit of investigations performed at six CN departments in Dublin compared patient groups from regions with (Eastern Regional Health Authority--ERHA) and without (NWHB) local CN departments. 4954 records were audited. CN activity was lower than internationally expected (ERHA group 52% of expected, NWHB group 23% of expected). The 2 groups differ in the specialty of referring clinician (p < 0.0001). NWHB patients are more likely to be referred by clinicians outside their region (p < 0.0001) and wait longer for appointment (p < 0.0001). While there is an unmet demand for CN services in Ireland generally, the population of the NWHB is further disadvantaged. Tele-neurophysiology has the potential to provide fairer access to CN services across the country. The data from this study provide a baseline against which the outcome of investment in CN can be monitored and evaluated.

Effect of wearing an ice cooling jacket on repeat sprint performance in warm/humid conditions

OBJECTIVE

To examine the effect of cooling the skin with an ice jacket before and between exercise bouts (to simulate quarter and half time breaks) on prolonged repeat sprint exercise performance in warm/humid conditions.

METHODS

After an initial familiarisation session, seven trained male hockey players performed two testing sessions (seven days apart), comprising an 80 minute intermittent, repeat sprint cycling exercise protocol inside a climate chamber set at 30 degrees C and 60% relative humidity. On one occasion a skin cooling procedure was implemented (in random counterbalanced order), with subjects wearing an ice cooling jacket both before (for five minutes) and in the recovery periods (2 x 5 min and 1 x 10 min) during the test. Measures of performance (work done and power output on each sprint), heart rates, blood lactate concentrations, core (rectal) and skin temperatures, sweat loss, perceived exertion, and ratings of thirst, thermal discomfort, and fatigue were obtained in both trials.

RESULTS

In the cooling condition, chest (torso) skin temperature, thermal discomfort, and rating of thirst were all significantly lower (p<0.05), but no significant difference (p>0.05) was observed between conditions for measures of work done, power output, heart rate, blood lactate concentration, core or mean skin temperature, perceived exertion, sweat loss, or ratings of fatigue. However, high effect sizes indicated trends to lowered lactate concentrations, sweat loss, and mean skin temperatures in the cooling condition.

CONCLUSIONS

The intermittent use of an ice cooling jacket, both before and during a repeat sprint cycling protocol in warm/humid conditions, did not improve physical performance, although the perception of thermal load was reduced. Longer periods of cooling both before and during exercise (to lower mean skin temperature by a greater degree than observed here) may be necessary to produce such a change.

Gender and the integration of acoustic dimensions of prosody: implications for clinical studies

This study was conducted to detect the existence of a relationship between spectral and temporal prosodic cues and to examine gender differences in any such relationship. The rationale for the investigation was to gain a greater understanding of normal prosody and the requirements for control groups in clinical studies of prosody. Ten male and 10 female speakers with no known speech or neurological deficits participated in the study. They performed a reading task which involved delivering 10 sentences first with a declarative and then repeated with an interrogative intonation (20 sentences per speaker). Intrasubject and intersubject analyses of the speech data revealed a dependence of pitch on duration that differed between male and female speakers. Significant differences between the genders were also found in speech rate, pitch range, and pitch slope. The findings suggest that an integrated treatment of acoustic cues may provide a more invariant feature of normal prosody against which clinical groups may be compared. The data also imply that in clinical studies of the production of prosody gender should be carefully controlled.

Accuracy and validity of stereology as a quantitative method for assessment of human temporal lobe volumes acquired by magnetic resonance imaging

The object of this study was to compare the accuracy and validity of stereology as a method for determining whole temporal lobe volume with the more established technique of semi-automated thresholding and tracing. Ten, fixed, post-mortem human brains, were imaged using a three dimensional (3D) acquisition protocol. The volume of the left temporal lobe, dissected from each brain, was determined by fluid displacement. Each volume was compared to measurements obtained from magnetic resonance images (MRI) of the post-mortem brain using each of the two segmentation methods. Post-acquisition processing was performed using MEASURE software. Three investigators performed each measurement three times using each method, yielding a total of 180 measurements. Stereology took, on average, half the time of thresholding/tracing. Using a clinically acceptable variation for 95% of repeat measures; both intra-observer and inter-observer variation were acceptable for each technique. However, validity, as demonstrated by graphs of agreement against water displacement showed that the "limits of agreement" using stereology were within the acceptable range, while those using the thresholding/tracing technique were not. Quantitative estimates of variation and a graphical representation of the limits of agreement show that stereology is at least as precise as the thresholding/tracing method but is superior in terms of speed and validity. This has broad implications for published estimates of brain region volumes in human diseases such as epilepsy, dementia and other neurodegenerative disorders.

An international survey of long-term video/EEG services

To determine current practices in the provision of video-EEG services, the authors conducted an international survey by post. The aim of the survey was to evaluate, by reference to other centres, how and why certain things are done, be assured that their own center is providing a quality service, identify weaknesses in their service, and from this, set improvement goals and objectives. A purposive sampling method was used by sending questionnaires to 78 hospitals where it was believed a long-term video-EEG monitoring service existed. Completed survey questionnaires were returned from 42 centers. Although the survey mechanism may have resulted in self-selection bias, evaluation of the responses provides information on patient management, staffing levels, equipment, and equipment management. Ultimately, these data may aid in identifying a minimum set of requirements for the provision of a video-EEG telemetry service.

The application of d.c. electrical stimulation in evoking and recording gustatory brain potentials

Evidence exists which supports the hypothesis that electrical stimulation of appropriate parameters can fulfil the fundamental requirements for an effective evoked potential taste stimulus. Nevertheless, it had previously been considered that electrical taste stimulation is inadequate for evoking gustatory brain potentials. Consequently, the majority of the earlier attempts to record gustatory evoked potentials (GEPs) reported in the literature have employed chemical stimulus techniques. The design of an electrical taste stimulator and its interface to an evoked potential recording unit is described. The first human brain potentials recorded with this system are presented, among which are those attributable to taste pathway activation. Following future work to unequivocally confirm that taste evoked brain potentials are achievable with this system, it has potential to become a clinically valuable tool.

Discrimination of prosody and music by normal children

Prosody or the melody of speech is the process used to alter the meaning (linguistic prosody) or emotional force (affective prosody) of a sentence. The components of prosody are rhythm, pitch, tone and stress and they are articulated by modulation of the acoustic correlates of prosody; frequency, duration and amplitude. Little is known about the development of prosody in normal children other than that it appears to be a precursor to the further acquisition of normal language. In order to examine the development of the perception of prosody in normal children, a group of 40 neurologically normal children aged between 5 and 9 years were subjected to a number of prosodic recognition tasks. The objective was to modify a number of existing tasks and to devise a number of new ones to test both linguistic and affective prosody and the appreciation of affective cues in music. The results indicate a step-wise improvement in perceptual contours up to 8.5 years old. However the perception of emotion in music appears highly developed early on in development. This study provides normative data and is the first report of a comparison between the development of prosodic and musical appreciation in this age group of normal children.

Prosodic preservation in Landau-Kleffner syndrome: a case report

Landau-Kleffner syndrome (LKS) is a rare acquired condition of auditory verbal agnosia and convulsive disorder in children. It has been proposed that there is a functional relationship between electrical disturbance and the speech defect. Prosody or the melody of language, as described by Monrad-Krohn (1947), is one aspect of non-verbal communication which is distributed bilaterally in the brain. Prosodic parameters of expression and perception in one 7.5-year-old child were tested to see if they were preserved as a means of communication. The child was observed during video-electroencephalogram (EEG) monitoring over a 48-hour period. All utterances were recorded and subject to analysis for the salience and variation of acoustic correlates of prosody. Prosodic comprehension was measured using specific perceptual tasks previously presented to normal children between the ages of 5.5 and 8.5. Despite being unable to meaningfully use or perceive phonemes, the child was able to use variations in fundamental frequency, duration and intensity of utterances, to convey both emotional and propositional intent. Similarly, the child was able to discriminate prosodic contours of a male adult voice to an age equivalent to 5.5 to 6.5 years. This argues in favour of the notion for educating such children not only through the visual channel but also through the auditory channel.

Changes in performance, muscle metabolites, enzymes and fibre types after short sprint training

In contrast to endurance training, little research has been carried out to investigate the effects of short (< 10 s) sprint training on performance, muscle metabolism and fibre types. Nine fit male subjects performed a mean of 16 outdoor sprint running training sessions over 6 weeks. Distances sprinted were 30-80 m at 90-100% maximum speed and between 20 and 40 sprints were performed in each session. Endurance (maximal oxygen consumption; VO2max), sprint (10 m and 40 m times), sustained sprint (supramaximal treadmill run) and repeated sprint (6 x 40 m sprints, 24 s recovery between each) performance tests were performed before and after training. Muscle biopsy samples (vastus lateralis) were also taken to examine changes in metabolites, enzyme activities and fibre types. After training, significant improvements were seen in 40 m time (P < 0.01), supramaximal treadmill run time (P < 0.05), repeated sprint performance (P < 0.05) and VO2max (P < 0.01). Resting muscle concentrations of ATP and phosphocreatine did not change. Phosphorylase activity increased (P < 0.025), citrate synthase activity decreased (P < 0.01), but no significant changes were recorded in myokinase and phosphofructokinase activities. The proportion of type II muscle fibres increased significantly (P < 0.05). These results demonstrate that 6 weeks of short sprint training can improve endurance, sprint and repeated sprint ability in fit subjects. Increases in the proportion of type II muscle fibres are also possible with this type of training.

Muscle phosphocreatine repletion following single and repeated short sprint efforts

Phosphocreatine (PCr) repletion following either single (1x6 s, n=7) or repeated (5x6 s, departing every 30 s, n=8) maximal short sprint cycling efforts was measured in separate groups of trained subjects. Muscle biopsies (vastus lateralis) were taken pre-exercise before warming up, and then at 10 s, 30 s and 3 min post-exercise. After the 1 x 6 s sprint PCr concentration was respectively, 55% (10 s; P<0.01), 69% (30 s; P<0.01) and 90% (3 min; NS) of the pre-exercise value (mean+/-SD) (81.1+/-7.4 mmol x kg(-1) DM), whereas after the 5x6 s sprints, PCr concentration was, respectively, 27% (10 s; P<0.01), 45% (30 s; P<0.01) and 84% (3 min; P<0.01) of the pre-exercise value (77.1+/-4.9 mmol x kg(-1) DM). PCr concentration was correlated with muscle lactate at 30 s (r=-0.82; P<0.05) and 3 min of recovery (r=-0.94; P<0.01) for the 1x6 s sprint, but not for the 5x6 s sprints. The extent of PCr repletion was significantly greater after the 5x6 s sprints than the 1x6 s sprint between both 10 s and 30 s and 30 s and 3 min, despite lower PCr levels at 10 s, 30 s and 3 min following the 5x6 s sprints. Full repletion of PCr is likely to take longer after repeated sprints than single short sprints because of a greater degree of PCr depletion, such that replenishment must commence from lower PCr levels rather than because of slower rates of repletion.

Image processing of videofluoroscopy of patients with velopharyngeal insufficiency and hypernasal speech

Eleven patients with hypernasal speech and velopharyngeal insufficiency (VPI), together with five normals, were evaluated by videofluoroscopy to assess velopharyngeal movement, velar lift and lateral pharyngeal wall movement. Computer processing of the images obtained was used to compensate for initial poor quality images by contrast and edge enhancement techniques and to provide objective measurement of the movements involved. It was demonstrated that objective computer aided analysis of videofluoroscopic images is feasible and may provide additional subtle diagnostic information when nasendoscopy is unavailable. In addition, results obtained showed an increased degree of velar lift and lateral pharyngeal wall movement for the more severely affected patients. These suggest a compensatory mechanism in operation for the more severe cases of VPI.

Model for a controlled-release drug delivery safety system with permeable and erodible coatings

Models of drug delivery devices that employ erodible permeable coatings must take care to avoid the unacceptably high rate of release that arises as the erodible coating disappears and the barrier to drug release vanishes. One solution to this safety problem has been to exhaust the drug reservoir just before this condition occurs. This design has the disadvantage of placing demands of high accuracy on the quality control in the fabrication of the device. A drug delivery system of cylindrical symmetry is proposed that uses two permeable coatings on a drug-containing core. Only the outer of the two coatings is erodible; the inner safety coating and the core are inert. Calculations are performed to design the device that can yield constant drug delivery rates while avoiding the possibility of explosive late drug release.