Human factors in anaesthesia: a narrative review

Healthcare relies on high levels of human performance, as described by the 'human as the hero' concept. However, human performance varies and is recognised to fall in high-pressure situations, meaning that it is not a reliable method of ensuring safety. Other safety-critical industries embed human factors principles into all aspects of their organisations to improve safety and reduce reliance on exceptional human performance; there is potential to do the same in anaesthesia. Human factors is a broad-based scientific discipline which aims to make it as easy as possible for workers to do things correctly. The human factors strategies most likely to be effective are those which 'design out' the chance of an error or adverse event occurring. When errors or adverse events do happen, barriers are in place to trap them and reduce the risk of progression to patient and/or worker harm. If errors or adverse events are not trapped by these barriers, mitigations are in place to minimise the consequences. Non-technical skills form an important part of human factors barriers and mitigation strategies and include: situation awareness; decision-making; task management; and team working. Human factors principles are not a substitute for proper investment and appropriate staffing levels. Although applying human factors science has the potential to save money in the long term, its proper implementation may require investment before reward can be reaped. This narrative review describes what is known about human factors in anaesthesia to date.

Implementing human factors in anaesthesia: guidance for clinicians, departments and hospitals: Guidelines from the Difficult Airway Society and the Association of Anaesthetists: Guidelines from the Difficult Airway Society and the Association of Anaesthetists

Human factors is an evidence-based scientific discipline used in safety critical industries to improve safety and worker well-being. The implementation of human factors strategies in anaesthesia has the potential to reduce the reliance on exceptional personal and team performance to provide safe and high-quality patient care. To encourage the adoption of human factors science in anaesthesia, the Difficult Airway Society and the Association of Anaesthetists established a Working Party, including anaesthetists and operating theatre team members with human factors expertise and/or interest, plus a human factors scientist, an industrial psychologist and an experimental psychologist/implementation scientist. A three-stage Delphi process was used to formulate a set of 12 recommendations: these are described using a 'hierarchy of controls' model and classified into design, barriers, mitigations and education and training strategies. Although most anaesthetic knowledge of human factors concerns non-technical skills, such as teamwork and communication, human factors is a broad-based scientific discipline with many other additional aspects that are just as important. Indeed, the human factors strategies most likely to have the greatest impact are those related to the design of safe working environments, equipment and systems. While our recommendations are primarily provided for anaesthetists and the teams they work with, there are likely to be lessons for others working in healthcare beyond the speciality of anaesthesia.

Intra-Areal Visual Topography in Primate Brains Mapped with Probabilistic Tractography of Diffusion-Weighted Imaging

Noninvasive diffusion-weighted magnetic resonance imaging (dMRI) can be used to map the neural connectivity between distinct areas in the intact brain, but the standard resolution achieved fundamentally limits the sensitivity of such maps. We investigated the sensitivity and specificity of high-resolution postmortem dMRI and probabilistic tractography in rhesus macaque brains to produce retinotopic maps of the lateral geniculate nucleus (LGN) and extrastriate cortical visual area V5/MT based on their topographic connections with the previously established functional retinotopic map of primary visual cortex (V1). We also replicated the differential connectivity of magnocellular and parvocellular LGN compartments with V1 across visual field positions. Predicted topographic maps based on dMRI data largely matched the established retinotopy of both LGN and V5/MT. Furthermore, tractography based on in vivo dMRI data from the same macaque brains acquired at standard field strength (3T) yielded comparable topographic maps in many cases. We conclude that tractography based on dMRI is sensitive enough to reveal the intrinsic organization of ordered connections between topographically organized neural structures and their resultant functional organization.

Regional analgesia for lower leg trauma and the risk of acute compartment syndrome: Guideline from the Association of Anaesthetists

Pain resulting from lower leg injuries and consequent surgery can be severe. There is a range of opinion on the use of regional analgesia and its capacity to obscure the symptoms and signs of acute compartment syndrome. We offer a multi-professional, consensus opinion based on an objective review of case reports and case series. The available literature suggested that the use of neuraxial or peripheral regional techniques that result in dense blocks of long duration that significantly exceed the duration of surgery should be avoided. The literature review also suggested that single-shot or continuous peripheral nerve blocks using lower concentrations of local anaesthetic drugs without adjuncts are not associated with delays in diagnosis provided post-injury and postoperative surveillance is appropriate and effective. Post-injury and postoperative ward observations and surveillance should be able to identify the signs and symptoms of acute compartment syndrome. These observations should be made at set frequencies by healthcare staff trained in the pathology and recognition of acute compartment syndrome. The use of objective scoring charts is recommended by the Working Party. Where possible, patients at risk of acute compartment syndrome should be given a full explanation of the choice of analgesic techniques and should provide verbal consent to their chosen technique, which should be documented. Although the patient has the right to refuse any form of treatment, such as the analgesic technique offered or the surgical procedure proposed, neither the surgeon nor the anaesthetist has the right to veto a treatment recommended by the other.

Nine-year prospective efficacy and safety of brain-responsive neurostimulation for focal epilepsy

OBJECTIVE

To prospectively evaluate safety and efficacy of brain-responsive neurostimulation in adults with medically intractable focal onset seizures (FOS) over 9 years.

METHODS

Adults treated with brain-responsive neurostimulation in 2-year feasibility or randomized controlled trials were enrolled in a long-term prospective open label trial (LTT) to assess safety, efficacy, and quality of life (QOL) over an additional 7 years. Safety was assessed as adverse events (AEs), efficacy as median percent change in seizure frequency and responder rate, and QOL with the Quality of Life in Epilepsy (QOLIE-89) inventory.

RESULTS

Of 256 patients treated in the initial trials, 230 participated in the LTT. At 9 years, the median percent reduction in seizure frequency was 75% (p < 0.0001, Wilcoxon signed rank), responder rate was 73%, and 35% had a ≥90% reduction in seizure frequency. We found that 18.4% (47 of 256) experienced ≥1 year of seizure freedom, with 62% (29 of 47) seizure-free at the last follow-up and an average seizure-free period of 3.2 years (range 1.04-9.6 years). Overall QOL and epilepsy-targeted and cognitive domains of QOLIE-89 remained significantly improved (p < 0.05). There were no serious AEs related to stimulation, and the sudden unexplained death in epilepsy (SUDEP) rate was significantly lower than predefined comparators (p < 0.05, 1-tailed χ2).

CONCLUSIONS

Adjunctive brain-responsive neurostimulation provides significant and sustained reductions in the frequency of FOS with improved QOL. Stimulation was well tolerated; implantation-related AEs were typical of other neurostimulation devices; and SUDEP rates were low.

CLINICALTRIALSGOV IDENTIFIER

NCT00572195.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that brain-responsive neurostimulation significantly reduces focal seizures with acceptable safety over 9 years.

Using RNA Sequencing to Characterize the Tumor Microenvironment

RNA sequencing (RNA-seq) is an integral tool in immunogenomics, allowing for interrogation of the transcriptome of a tumor and its microenvironment. Analytical methods to deconstruct the genomics data can then be applied to infer gene expression patterns associated with the presence of various immunocyte populations. High quality RNA-seq is possible from formalin-fixed, paraffin-embedded (FFPE), fresh-frozen, and fresh tissue, with a wide variety of sequencing library preparation methods, sequencing platforms, and downstream bioinformatics analyses currently available. Selection of an appropriate library preparation method is largely determined by tissue type, quality of RNA, and quantity of RNA. Downstream of sequencing, many analyses can be applied to the data, including differential gene expression analysis, immune gene signature analysis, gene pathway analysis, T/B-cell receptor inference, HLA inference, and viral transcript quantification. In this chapter, we will describe our workflow for RNA-seq from bulk tissue to evaluable data, including extraction of RNA, library preparation methods, sequencing of libraries, alignment and quality assurance of data, and initial downstream analyses of RNA-seq data to extract relevant immunogenomics features. Systems biology methods that draw additional insights by integrating these features are covered further in Chapters 28 - 30 .

White matter changes in the perforant path area in patients with amyotrophic lateral sclerosis

OBJECTIVE

The aim of this study was to test the hypothesis that white matter degeneration of the perforant path - as part of the Papez circuit - is a key feature of amyotrophic lateral sclerosis (ALS), even in the absence of frontotemporal dementia (FTD) or deposition of pTDP-43 inclusions in hippocampal granule cells.

METHODS

We used diffusion Magnetic Resonance Imaging (dMRI), polarized light imaging (PLI) and immunohistochemical analysis of post mortem hippocampus specimens from controls (n = 5) and ALS patients (n = 14) to study white matter degeneration in the perforant path.

RESULTS

diffusion Magnetic Resonance Imaging demonstrated a decrease in fractional anisotropy (P = 0.01) and an increase in mean diffusivity (P = 0.01) in the perforant path in ALS compared to controls. PLI-myelin density was lower in ALS (P = 0.05) and correlated with fractional anisotropy (r = 0.52, P = 0.03). These results were confirmed by immunohistochemistry; both myelin (proteolipid protein, P = 0.03) and neurofilaments (SMI-312, P = 0.02) were lower in ALS. Two out of the fourteen ALS cases showed pTDP-43 pathology in the dentate gyrus, but with comparable myelination levels in the perforant path to other ALS cases.

CONCLUSION

We conclude that degeneration of the perforant path occurs in ALS patients and that this may occur before, or independent of, pTDP-43 aggregation in the dentate gyrus of the hippocampus. Future research should focus on correlating the degree of cognitive decline to the amount of white matter atrophy in the perforant path.

Microstructural imaging of the human brain with a 'super-scanner': 10 key advantages of ultra-strong gradients for diffusion MRI

The key component of a microstructural diffusion MRI 'super-scanner' is a dedicated high-strength gradient system that enables stronger diffusion weightings per unit time compared to conventional gradient designs. This can, in turn, drastically shorten the time needed for diffusion encoding, increase the signal-to-noise ratio, and facilitate measurements at shorter diffusion times. This review, written from the perspective of the UK National Facility for In Vivo MR Imaging of Human Tissue Microstructure, an initiative to establish a shared 300 mT/m-gradient facility amongst the microstructural imaging community, describes ten advantages of ultra-strong gradients for microstructural imaging. Specifically, we will discuss how the increase of the accessible measurement space compared to a lower-gradient systems (in terms of Δ, b-value, and TE) can accelerate developments in the areas of 1) axon diameter distribution mapping; 2) microstructural parameter estimation; 3) mapping micro-vs macroscopic anisotropy features with gradient waveforms beyond a single pair of pulsed-gradients; 4) multi-contrast experiments, e.g. diffusion-relaxometry; 5) tractography and high-resolution imaging in vivo and 6) post mortem; 7) diffusion-weighted spectroscopy of metabolites other than water; 8) tumour characterisation; 9) functional diffusion MRI; and 10) quality enhancement of images acquired on lower-gradient systems. We finally discuss practical barriers in the use of ultra-strong gradients, and provide an outlook on the next generation of 'super-scanners'.

A comparison of electronic and manual fracture risk assessment tools in screening elderly male US veterans at risk for osteoporosis

This study compares four screening tools in their ability to predict osteoporosis. We found that there was no significant difference between the tools. These results provide support for the use of automated screening tools which work in conjunction with the electronic medical record and help improve screening rates for osteoporosis.

INTRODUCTION

The purpose of this study is to compare the performance of four fracture risk assessment tools (FRATs) in identifying osteoporosis by bone mineral density (BMD) T-score: Veterans Affairs Fracture Absolute Risk Assessment Tool (VA-FARA), World Health Organization's Fracture Risk Assessment Tool (FRAX), electronic FRAX (e-FRAX), and Osteoporosis Self-Assessment Screening Tool (OST).

METHODS

We performed a cross-sectional analysis of all patients enrolled in the VA Salt Lake City bone health team (BHT) who had completed a DXA scan between February 1, 2012, and February 1, 2013. DXA scan results were obtained by chart abstraction. For calculation of FRAX, osteoporosis risk factors were obtained from a screening questionnaire completed prior to DXA. For VA-FARA and e-FRAX, risk factors were derived from the electronic medical record (EMR). Clinical risk scores were calculated and compared against the gold standard of DXA-based osteoporosis. Sensitivity, specificity, and predictive values were calculated. Receiver operator characteristic (ROC) curves were plotted, and areas under the curve (AUC) were compared.

RESULTS

A cohort of 463 patients met eligibility criteria (mean age 80.4 years). One hundred twelve patients (24%) had osteoporosis as defined by DXA T-score ≤-2.5. Sensitivity, specificity, and predictive values were calculated. ROC statistics were compared and did not reach statistical significance difference between FRATs in identifying DXA-based osteoporosis.

CONCLUSIONS

Our study suggests that all FRATs tested perform similarly in identifying osteoporosis among elderly, primarily Caucasian, male veterans. If these electronic screening methods perform similarly for fracture outcomes, they could replace manual FRAX and thus improve efficiency in identifying individuals who should be sent for DXA scan.

PEAR: PEriodic and ApeRiodic signal separation for fast FMRI

Undersampling of functional MRI (fMRI) data leads to increased temporal resolution, as it allows shorter acquisition time per frame. High quality reconstruction of fMRI data from undersampled measurements requires proper modeling of the fMRI data. Recent publications suggest that the fMRI signal is a superposition of periodic and aperiodic signals. In this paper we develop an fMRI reconstruction approach based on this modeling. The fMRI data is assumed to be composed of two components: a component that holds a sum of periodic signals which is sparse in the temporal Fourier domain and an component that holds the remaining imaging information (consisting of the background and aperiodic signals) which has low rank. Data reconstruction is done by solving a constrained problem that enforces a fixed, moderate rank on one of the components, and a limited number of temporal frequencies on the other. Our approach is coined PEAR - PEriodic and ApeRiodic signal separation for fast fMRI. Experimental results are based on fMRI reconstruction using realistic timecourses. Evaluation was performed both quantitatively and visually versus ground truth. Results demonstrate PEAR's improvement in estimating the realistic timecourses versus state-of-the-art approaches at acceleration ratio of R=16.6.

Individual Differences in the Alignment of Structural and Functional Markers of the V5/MT Complex in Primates

Extrastriate visual area V5/MT in primates is defined both structurally by myeloarchitecture and functionally by distinct responses to visual motion. Myelination is directly identifiable from postmortem histology but also indirectly by image contrast with structural magnetic resonance imaging (sMRI). First, we compared the identification of V5/MT using both sMRI and histology in Rhesus macaques. A section-by-section comparison of histological slices with in vivo and postmortem sMRI for the same block of cortical tissue showed precise correspondence in localizing heavy myelination for V5/MT and neighboring MST. Thus, sMRI in macaques accurately locates histologically defined myelin within areas known to be motion selective. Second, we investigated the functionally homologous human motion complex (hMT+) using high-resolution in vivo imaging. Humans showed considerable intersubject variability in hMT+ location, when defined with myelin-weighted sMRI signals to reveal structure. When comparing sMRI markers to functional MRI in response to moving stimuli, a region of high myelin signal was generally located within the hMT+ complex. However, there were considerable differences in the alignment of structural and functional markers between individuals. Our results suggest that variation in area identification for hMT+ based on structural and functional markers reflects individual differences in human regional brain architecture.

Microscale screening of antibody libraries as maytansinoid antibody-drug conjugates

Antibody-drug conjugates (ADCs) are of great interest as targeted cancer therapeutics. Preparation of ADCs for early stage screening is constrained by purification and biochemical analysis techniques that necessitate burdensome quantities of antibody. Here we describe a method, developed for the maytansinoid class of ADCs, enabling parallel conjugation of antibodies in 96-well format. The method utilizes ∼ 100 µg of antibody per well and requires <5 µg of ADC for characterization. We demonstrate the capabilities of this system using model antibodies. We also provide multiple examples applying this method to early-stage screening of maytansinoid ADCs. The method can greatly increase the throughput with which candidate ADCs can be screened in cell-based assays, and may be more generally applicable to high-throughput preparation and screening of different types of protein conjugates.

Dentatorubrothalamic tract localization with postmortem MR diffusion tractography compared to histological 3D reconstruction

Diffusion-weighted imaging (DWI) tractography is a technique with great potential to characterize the in vivo anatomical position and integrity of white matter tracts. Tractography, however, remains an estimation of white matter tracts, and false-positive and false-negative rates are not available. The goal of the present study was to compare postmortem tractography of the dentatorubrothalamic tract (DRTT) by its 3D histological reconstruction, to estimate the reliability of the tractography algorithm in this specific tract. Recent studies have shown that the cerebellum is involved in cognitive, language and emotional functions besides its role in motor control. However, the exact working mechanism of the cerebellum is still to be elucidated. As the DRTT is the main output tract it is of special interest for the neuroscience and clinical community. A postmortem human brain specimen was scanned on a 7T MRI scanner using a diffusion-weighted steady-state free precession sequence. Tractography was performed with PROBTRACKX. The specimen was subsequently serially sectioned and stained for myelin using a modified Heidenhain–Woelke staining. Image registration permitted the 3D reconstruction of the histological sections and comparison with MRI. The spatial concordance between the two modalities was evaluated using ROC analysis and a similarity index (SI). ROC curves showed a high sensitivity and specificity in general. Highest measures were observed in the superior cerebellar peduncle with an SI of 0.72. Less overlap was found in the decussation of the DRTT at the level of the mesencephalon. The study demonstrates high spatial accuracy of postmortem probabilistic tractography of the DRTT when compared to a 3D histological reconstruction. This gives hopeful prospect for studying structure–function correlations in patients with cerebellar disorders using tractography of the DRTT.

Abstract 5442: Microscale methods for preparation and screening of antibody-drug conjugates

Antibody-drug conjugates (ADCs) are hybrid biotherapeutics that combine the targeting specificity of monoclonal antibodies with chemically conjugated, highly potent small molecule chemotherapeutics. Using established research scale approaches, the amount of antibody material needed to prepare candidate ADCs far exceeds the quantities required for initial in vitro screening. The need to scale up production across many antibodies slows down early lead selection efforts and wastes material. We have therefore developed methods for conjugating multiple antibodies with ADC payloads in parallel at the 50-150 μg scale in 96-well plates. Pilot reactions show that antibodies can be titrated to different final drug:antibody ratios (DARs) with different payloads, and that differences in pH can alter the reaction kinetics with useful effects. We show that 96-well centrifugal ultrafiltration enables highly parallel ADC purification while maintaining the rigorous removal of residual cytotoxic impurities observed with more established methods such as gel filtration chromatography. In addition, we describe characterization of microscale ADCs using a single chromatographic assay requiring ∼5 μg of material. The resulting platform reduces the required input quantity of antibody required for in vitro ADC screening by at least 5-10 fold. It also enables much higher conjugation throughput with concomitant decrease in time needed to generate and characterize ADCs.

To assess the utility of the platform for ranking candidate antibodies, we compare in vitro cytotoxicity results for a panel of ADCs produced by both microscale and research scale methods. We also present three example screens in which antibody libraries of 10-85 members against different targets were conjugated using microscale methods and the resulting ADCs ranked by in vitro potency. For each antibody library, the screen size, conjugation conditions, and target DAR range were adjusted to suit the target biology, antibody type,and payload class. For example, we present evidence suggesting that, for targets in which functional antibody activity is not observed, normalization of DAR to the 2-6 range is adequate for screening. Across the screens, the success rates for producing ADC in quantity and quality suitable for screening were in the 75-90% range, using 200-600 μg of input antibody. Cytotoxic potencies ranging over 2-3 orders of magnitude were observed in the resulting ADC libraries, suggesting that microscale conjugation can rapidly focus ADC discoverycampaigns on high potency molecules.

For early stage antibody and ADC screening efforts, we find that microscale conjugation methods yield ADCs that can substitute for traditionally prepared conjugates. We expect these methods will be applicable across many different ADC targets and payloads, and possibly applicable more generally to conjugated macromolecule therapeutic or diagnostic reagents.

Citation Format: Nicholas C. Yoder, Kalli C. Catcott, Molly A. McShea, Carl Uli Bialucha, Parmita Saxena, Chen Bai, Kathy L. Miller, Thomas G. Gesner, Mikias Woldegiorgis, Stuart W. Hicks, Megan E. Lewis, Michael S. Fleming, Hans K. Erickson, Seth E. Ettenberg, Thomas A. Keating. Microscale methods for preparation and screening of antibody-drug conjugates. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5442. doi:10.1158/1538-7445.AM2015-5442

Social network size affects neural circuits in macaques

It has been suggested that variation in brain structure correlates with the sizes of individuals' social networks. Whether variation in social network size causes variation in brain structure, however, is unknown. To address this question, we neuroimaged 23 monkeys that had been living in social groups set to different sizes. Subject comparison revealed that living in larger groups caused increases in gray matter in mid-superior temporal sulcus and rostral prefrontal cortex and increased coupling of activity in frontal and temporal cortex. Social network size, therefore, contributes to changes both in brain structure and function. The changes have potential implications for an animal's success in a social context; gray matter differences in similar areas were also correlated with each animal's dominance within its social network.

The danger of systematic bias in group-level FMRI-lag-based causality estimation

Schippers, Renken and Keysers (NeuroImage, 2011) present a simulation of multi-subject lag-based causality estimation. We fully agree that single-subject evaluations (e.g., Smith et al., 2011) need to be revisited in the context of multi-subject studies, and Schippers' paper is a good example, including detailed multi-level simulation and cross-subject statistical modelling. The authors conclude that "the average chance to find a significant Granger causality effect when no actual influence is present in the data stays well below the p-level imposed on the second level statistics" and that "when the analyses reveal a significant directed influence, this direction was accurate in the vast majority of the cases". Unfortunately, we believe that the general meaning that may be taken from these statements is not supported by the paper's results, as there may in reality be a systematic (group-average) difference in haemodynamic delay between two brain areas. While many statements in the paper (e.g., the final two sentences) do refer to this problem, we fear that the overriding message that many readers may take from the paper could cause misunderstanding.

Molecular alterations of the IDH1 gene in AML: a Children's Oncology Group and Southwest Oncology Group study

Recent whole-genome sequencing efforts led to the identification of IDH1^R132 mutations in AML patients. We studied the prevalence and clinical implications of IDH1 genomic alterations in pediatric and adult AML. Diagnostic DNA from 531 AML patients treated on Children’s Oncology Group trial COG-AAML03P1 (N=257), and Southwest Oncology Group trials SWOG-9031, SWOG-9333, and SWOG-9500 (N=274), were tested for IDH1 mutations. Codon R132 mutations were absent in the pediatric cohort, but were found in 12/274 adult patients (4.4%, 95% CI 2.3-7.5%). IDH1^R132 mutations occurred most commonly in patients with normal karyotype, and those with FLT3/ITD and NPMc mutations. Patients with IDH1^R132 mutations trended towards higher median diagnostic WBC counts (59.2 × 10⁹/L vs. 29.1 × 10⁹/L, P=0.19) than those without mutations, but the two groups did not differ significantly in age, bone marrow blast percentage, overall survival, or relapse-free survival. Eleven patients (2.1%) harbored a novel V71I sequence alteration, which was found to be a germline polymorphism. IDH1 mutations were not detected in pediatric AML, and are uncommon in adult AML.

Short-term oral corticosteroid therapy for acute haemarthrosis in haemophilia patients with high-titre inhibitors

Treatment of acute bleeding events is unsatisfactory in patients with haemophilia and high-titre factor VIII (FVIII) inhibitors. In order to determine whether short-term corticosteroid therapy enhances resolution of the signs and symptoms of acute haemarthrosis, we performed a randomized, double-blind, placebo-controlled study in children with FVIII deficiency and high-titre inhibitors receiving Factor Eight Inhibitor Bypass Activity (FEIBA) for acute haemorrhagic events. At each haemarthrosis, patients were randomized to receive either prednisolone 2 mg kg(-1) day(-1) or placebo-divided t.i.d. for 2 days (six doses) in addition to FEIBA. The primary endpoint was the number of subsequent doses of FEIBA required. The effect of the study medication was also assessed subjectively by patients or parents, by physical examination and by repeated haemorrhages into the joint. During the study period, seven patients were enrolled with 45 evaluable events, 24 treated with prednisolone and 21 with placebo. An average of 2.08 and 1.86 doses of FEIBA were infused in the prednisolone- and placebo-treated patients, respectively. By Wilcoxon Rank Sum Test, there was no statistically significant difference in number of additional infusions of FEIBA or duration of symptoms between the corticosteroid and placebo arms. We conclude that there is no significant benefit of a 2-day course of oral corticosteroids as adjunctive therapy for haemarthrosis in patients with haemophilia and a high-titre inhibitor.

Nuclear medicine technologists and unauthorized self-injections

An Office of Investigation (OI) investigation by the U.S. Nuclear Regulatory Commission (NRC) determined that, on three separate occasions over the past 10 years, technologists in one licensed nuclear medicine program were injected with radiopharmaceuticals without Authorized User knowledge or approval. The most recent instance, the one that precipitated the investigation, was discovered by the licensee and self-reported to the NRC; the other two instances were discovered during the OI investigation and came as a complete surprise to the licensee. In a mediated Alternative Dispute Resolution (ADR) involving the licensee, a professional, independent mediator and representatives of the NRC, an agreement was worked out whereby the licensee would admit to the violations and work with the NRC to inform other licensees that this is not an acceptable practice and that there are additional precautions that licensees can and should take to assure that such violations do not happen on their watch.

The CD200 receptor is a novel and potent regulator of murine and human mast cell function

CD200R is a member of the Ig supergene family that is primarily expressed on myeloid cells. Recent in vivo studies have suggested that CD200R is an inhibitory receptor capable of regulating the activation threshold of inflammatory immune responses. Here we provide definitive evidence that CD200R is expressed on mouse and human mast cells and that engagement of CD200R by agonist Abs or ligand results in a potent inhibition of mast cell degranulation and cytokine secretion responses. CD200R-mediated inhibition of FcepsilonRI activation was observed both in vitro and in vivo and did not require the coligation of CD200R to FcepsilonRI. Unlike the majority of myeloid inhibitory receptors, CD200R does not contain a phosphatase recruiting inhibitory motif (ITIM); therefore, we conclude that CD200R represents a novel and potent inhibitory receptor that can be targeted in vivo to regulate mast cell-dependent pathologies.

Determination of potential uterine (conceptus) doses from axial and helical CT scans

A tissue equivalent Rando Phantom and thermoluminescent dosimeters (TLDs) (LiF) were used to determine potential doses to the uterus at approximately the position of a conceptus from axial and helical CT scans of that region of the body. Doses were measured at the surface of the phantom and at various locations throughout the phantom. The results indicate that measurements taken on the surface of a patient or phantom are generally higher than the level at the location of the uterus within the patient. The results also indicate that the dose to tissue that is 12.7 cm (5 in) out of the direct beam is less than 10% of the dose within the beam. For tissues that are 20 cm (8 in) out of the beam, the dose is approximately 1% of the dose in the beam.

Consensus recommendations for use of central venous access devices in haemophilia

Venous access is essential for delivery of haemophilia factor concentrate. Wherever possible, peripheral veins remain the route of choice, and the use of central venous access devices (CVADs) should be limited to cases of clear need in patients with caregivers able to exercise diligence in CVAD care and should continue no longer than necessary. CVADs are of recognized value for repeated administration of coagulation factors in haemophilia, particularly for prophylaxis and immune tolerance therapy and in young children. Evidence to guide best practices has been fragmentary, and standardized methods for CVAD usage have yet to be established. We have developed management recommendations based upon available published evidence as well as extensive clinical experience. These recommendations address patient and CVAD selection; CVAD placement, care and removal; caregiver/patient guidance; and complications, including infection and thrombosis. In the absence of inhibitors, ports are recommended, primarily because of fewer associated infections than with external catheters. For patients with inhibitors, ports also appear to be associated with fewer infections. Infection is the most frequent complication, and recommendations to prevent and treat infections are supported by extensive clinical data and experience. Strict adherence to handwashing and aseptic technique are essential elements of catheter care. Evidence-based data regarding the detection and treatment of CVAD-related thrombotic complications are limited. Caregiver education is an integral part of CVAD use and the procedural practices of users should be regularly re-assessed. These recommendations provide a basis for sound current CVAD practice and are expected to undergo further refinements as new evidence is compiled and clinical experience is gained.

[Effect of infrared low power laser irradiation on blood acid-base balance and respiratory gases tension]

Small volume (0.5 ml) of arterial or venous rat's blood was subjected to impulse LPILR (lambda = 0.89 microns) in the light transparent cuvette. In arterial blood, a decrease of the pO2 (by 15.5 +/- 2.6%) and an increase of the pCO2 (by 22.0 +/- 4.8%) in respect to initial values, were determined. The acid-base shift from 7.39 +/- 0.02 to 7.34 +/- 0.02 was recorded. Only in few experiments, there were changes of pO2, pCO2 and pH in venous blood. Probable mechanism(s) of the mentioned parameters changes are discussed.

Assessment of the aesthetic quality of a selection of beaches in the Firth of Forth, Scotland

The aesthetic quality of fourteen beaches in the Firth of Forth, Scotland was surveyed between May and July 2002 using a protocol designed by the UK's National Aquatic Litter Group (NALG). Local authority beach cleaning regimes influence the amount of litter found on beaches. Frequent and thorough beach cleaning is necessary to maintain high aesthetic standards. Bathing and amenity beaches achieved higher aesthetic quality than non-bathing and non-amenity beaches. The aesthetic quality of rural and urban beaches was very similar. The NALG protocol appears more complicated to use than other beach litter surveys. However, the classification system generates results that are easily interpreted by the general public. Furthermore, the NALG protocol could be combined with coastal zone management plans as a useful environmental performance indicator.

Quest for a detrusor overactivity index

PURPOSE

Urge incontinence, which is the predominant type of geriatric incontinence, is generally attributed to detrusor overactivity. However, detrusor overactivity is present in up to half of continent elderly individuals. We postulated that detrusor overactivity associated with urge incontinence would be more severe but there are no established criteria for judging severity. Using urge incontinence frequency as a yardstick and controlling for nonurodynamic contributing factors we sought intrinsic lower urinary tract parameters that reflect detrusor overactivity severity. We postulated that parameters in 1 or more of 5 domains would be important, namely characteristics of uninhibited contraction, bladder capacity, bladder proprioception, detrusor contractility and sphincter adequacy.

MATERIALS AND METHODS

We analyzed data on 79 community dwelling incontinent individuals older than 60 years old. All subjects had urge incontinence on a 4-day voiding record and underwent multichannel videourodynamics. We examined the associations of urge incontinence frequency with the postulated key factors.

RESULTS

Multivariable analysis revealed that 24-hour urine output and functional bladder capacity consistently predicted urge incontinence frequency. Bladder proprioception was significant in some models. Uninhibited contraction pressure was another predictor. Surprisingly higher uninhibited contraction pressure was associated with lower urge incontinence frequency. This negative correlation was more pronounced in a subgroup with a less adequate sphincter but absent in those with good sphincter function, implying that low uninhibited contraction pressure does not necessarily indicate less severe detrusor overactivity but rather reflects sphincter inadequacy in many patients. Age was not independently associated with urge incontinence frequency.

CONCLUSIONS

We identified functional bladder capacity as a measure of detrusor overactivity severity. The measure commonly used, namely uninhibited contraction pressure, is inappropriate because it is severely confounded by sphincter function, especially in older individuals. Furthermore, we confirmed that urine output, and possibly bladder sensation and sphincter strength modify the clinical manifestation of detrusor overactivity.

Quest for a detrusor overactivity index

PURPOSE

Urge incontinence, which is the predominant type of geriatric incontinence, is generally attributed to detrusor overactivity. However, detrusor overactivity is present in up to half of continent elderly individuals. We postulated that detrusor overactivity associated with urge incontinence would be more severe but there are no established criteria for judging severity. Using urge incontinence frequency as a yardstick and controlling for nonurodynamic contributing factors we sought intrinsic lower urinary tract parameters that reflect detrusor overactivity severity. We postulated that parameters in 1 or more of 5 domains would be important, namely characteristics of uninhibited contraction, bladder capacity, bladder proprioception, detrusor contractility and sphincter adequacy.

MATERIALS AND METHODS

We analyzed data on 79 community dwelling incontinent individuals older than 60 years old. All subjects had urge incontinence on a 4-day voiding record and underwent multichannel videourodynamics. We examined the associations of urge incontinence frequency with the postulated key factors.

RESULTS

Multivariable analysis revealed that 24-hour urine output and functional bladder capacity consistently predicted urge incontinence frequency. Bladder proprioception was significant in some models. Uninhibited contraction pressure was another predictor. Surprisingly higher uninhibited contraction pressure was associated with lower urge incontinence frequency. This negative correlation was more pronounced in a subgroup with a less adequate sphincter but absent in those with good sphincter function, implying that low uninhibited contraction pressure does not necessarily indicate less severe detrusor overactivity but rather reflects sphincter inadequacy in many patients. Age was not independently associated with urge incontinence frequency.

CONCLUSIONS

We identified functional bladder capacity as a measure of detrusor overactivity severity. The measure commonly used, namely uninhibited contraction pressure, is inappropriate because it is severely confounded by sphincter function, especially in older individuals. Furthermore, we confirmed that urine output, and possibly bladder sensation and sphincter strength modify the clinical manifestation of detrusor overactivity.

Catheter-related deep venous thrombosis in children with hemophilia

Central venous catheters (CVCs) are a common adjunct to hemophilia therapy, but the risk of CVC-related deep venous thrombosis (DVT) in hemophiliacs is not well defined. In a previous study, 13 patients with CVCs had no radiographic evidence of DVT. However, recent abstracts and case studies demonstrate that DVT does occur. Therefore, this study sought to determine the frequency of DVT in children with hemophilia and long-term CVCs and to correlate venographic findings with clinical features. All hemophilia patients with tunneled subclavian CVCs in place for 12 months or more were candidates for evaluation. Patients were examined for physical signs of DVT and questioned about catheter dysfunction. Contrast venograms were obtained to identify DVT. Fifteen boys with severe hemophilia were evaluated, including 9 from the initially studied group of 13. Eight patients had evidence of DVT, 5 of whom previously had normal venograms. Five of 15 patients had clinical problems related to the CVC, all of whom had DVT. Four of 15 patients had suggestive physical signs; 3 had DVT. The mean duration of catheter placement for all patients was 57.5 months (range, 12-102 months). For patients with DVT, the mean duration was 66.6 +/- 7.5 months, compared to 49.5 +/- 7.2 months for patients without DVT (P =.06). No patient whose CVC was in place fewer than 48 months had an abnormal venogram. Many hemophilia patients with CVCs develop DVT of the upper venous system, and the risk increases with duration of catheter placement.

Some experiences with treating thyroid cancer patients

U.S. NRC Regulatory Guide 8.39 provides for the release of patients treated with 131I provided that predetermined calculations indicate that no member of the public will receive a total dose equivalent in excess of 5 mSv (500 mrem). When this condition cannot be met or there are other reasons for keeping the patient hospitalized after treatment, control of contamination and exposure from the patient must be taken into consideration. If the patients are hospitalized following treatment, decontaminating the patient's room after discharge and controlling the exposure potential from the patient are considerations for the hospital radiation safety staff. This paper reviews the experiences from fifty patients treated as inpatients over the past two years.

Contaminating incident investigation in medicine and biomedical research

Regardless of how well trained, experienced and careful individuals are, if they handle radioactive materials often enough they will eventually have a contaminating incident. When the incident occurs it is imperative that the proper actions are taken to control the incident, minimize contamination and exposure, assure that proper remediation is implemented, assure that the incident remains confined, that no others become contaminated or exposed and that effective remediation is documented. This paper discusses our approach to such incidents and discusses the incident report form and our philosophy of information recording.

Experience with a medical waste portal monitoring system

A portal monitor was installed to detect radioactivity in trash and laundry leaving the hospital facility. Experiences with selection, installation, calibration and detection capabilities are reviewed. Also reviewed are the topics used in training hospital employees on proper use of the monitor and response detected activity in trash or laundry.

A radiation safety infraction notification form

The use of a well constructed form can serve as an official notification of the violation of good radiation safety practice while providing a paper trail for documentation of corrective action.

Survey of distance technology use in AACN member schools

The American Association of Colleges of Nursing surveyed its members by using a 104-item instrument to determine the state of the art in distance technology use. Survey results indicated a recent acceleration of course offerings through distance technology at all levels of nursing education. The most cited reason for this was to improve access to nursing education. Resources for distance technology tended to reside in public, rather than private, institutions. Trends were for greater use of video and computer-based technologies. Although technology use is increasing, computers and other technologies are not used in the didactic or clinical educational experience in many schools. Areas for further evaluation are identified.

Transdermal estrogen replacement therapy in postmenopausal women previously treated for porphyria cutanea tarda

Oral contraceptives and postmenopausal estrogen replacement therapy are recognized as risk factors for the development of porphyria cutanea tarda (PCT) in women. The recommended clinical practice is to withhold estrogen therapy in women who have had phlebotomy therapy for PCT and are clinically and biochemically normal. We tested the safety and efficacy of transdermal estrogen replacement therapy in 7 women previously treated for PCT and compared them with 19 non-porphyric control subjects treated with transdermal or oral estrogens. Gonadotrophic hormone levels, estrogen levels, liver function studies, body iron stores, urine porphyrin excretion, and cytochrome P4501A2 (CYP1A2) activity were monitored for 1 year. Four of the women previously treated for PCT completed the study. None had evidence of a porphyric relapse. CYP1A2 activity, measured by three different methods, did not differ between study subjects receiving estrogens, patients with active PCT, and non-porphyric control subjects, nor did CYP1A2 activity change during the study period. Gonadotrophic hormone levels fell and estrogen levels rose in all women receiving estrogens. The administration of estrogens by the transdermal route appeared to be safe in the small number of subjects we studied and should be considered for women previously treated for PCT.

Adjuvant activity of monophosphoryl lipid A for nasal and oral immunization with soluble or liposome-associated antigen

The effectiveness of monophosphoryl lipid A (MPL) as a mucosal adjuvant was investigated following oral or intranasal (i.n.) administration of an aqueous adjuvant formulation of MPL (MPL-AF) added to soluble antigen or liposomal antigen or incorporated into liposomal antigen membranes. Groups of BALB/c female mice were immunized with 50 to 100 microg of free or liposomal Streptococcus mutans crude glucosyltransferase (C-GTF) with or without MPL-AF added to the vaccine or incorporated into the liposomal membrane. Plasma, saliva, vaginal wash, and fecal extract samples were collected biweekly following immunization and assessed for antigen-specific antibody activity by enzyme-linked immunosorbent assay (ELISA). Mice immunized by the i.n. route had higher levels of salivary, plasma, and vaginal immunoglobulin A (IgA) anti-C-GTF responses and higher levels of plasma IgG anti-C-GTF than the orally immunized groups. A second administration of the vaccine 14 weeks after the initial immunization resulted in an anamnestic response to C-GTF resulting in 10- and 100-fold increases in saliva and plasma IgA and plasma IgG, respectively (in the i.n. immunized groups). Mice receiving a second i.n. immunization with liposomal antigen and MPL-AF had higher salivary IgA anti-C-GTF responses than mice immunized with antigen plus MPL-AF or liposomal antigen (P < 0.05). Plasma IgG anti-C-GTF activity was highest in mice immunized by the i.n. route with antigen formulations containing MPL-AF (P < 0.05). These results demonstrate the effectiveness of MPL-AF as an adjuvant for potentiating mucosal and systemic immune responses to liposomal C-GTF following i.n. immunization.

Fertility and developmental neurotoxicity effects of inhaled hydrogen sulfide in Sprague-Dawley rats

In this study, we examined whether perinatal exposure by inhalation to hydrogen sulfide (H2S) had an adverse impact on pregnancy outcomes, offspring prenatal and postnatal development, or offspring behavior. Virgin male and female Sprague-Dawley rats (12 rats/sex/concentration) were exposed (0, 10, 30, or 80 ppm H2S; 6 h/day, 7 days/week) for 2 weeks prior to breeding. Exposures continued during a 2-week mating period (evidence of copulation = gestation day 0 = GD 0) and then from GD 0 through GD 19. Exposure of dams and their pups (eight rats/litter after culling) resumed between postnatal day (PND) 5 and 18. Adult male rats were exposed for 70 consecutive days. Offspring were evaluated using motor activity (PND 13, 17, 21, and 60+/-2), passive avoidance (PND 22+/-1 and 62+/-3), functional observation battery (PND 60+/-2), acoustic startle response (PND 21 and 62+/-3), and neuropathology (PND 23+/-2 and 61+/-2). There were no deaths and no adverse physical signs observed in F0 male or female rats during the study. A statistically significant decrease in feed consumption was observed in F0 male rats from the 80-ppm H2S exposure group during the first week of exposure. There were no statistically significant effects on the reproductive performance of the F0 rats as assessed by the number of females with live pups, litter size, average length of gestation, and the average number of implants per pregnant female. Exposure to H2S did not affect pup growth, development, or performance on any of the behavioral tests. The results of our study suggest that H2S is neither a reproductive toxicant nor a behavioral developmental neurotoxicant in the rat at occupationally relevant exposure concentrations (< or =10 ppm).

Radioisotope laboratory audits

Elsewhere in this issue, Robin Elliott outlined a successful program for performing annual radiation safety management program audits. The results of such audits provide a useful means of evaluating and correcting deficiencies or weaknesses in a radiation safety program. At our institution we also perform an annual audit of each radioisotope lab oratory for the same reasons.

The recovery of populations of dogwhelks suffering from imposex in the Firth of Forth 1987-1997/98

The impact of tributyltin (TBT) contamination on dogwhelk (Nucella lapillus) populations was assessed at 33 sites in the Firth of Forth, UK, during spring 1997 and summer 1998. The sex ratio of the animals; the ratio of juveniles to adults; the degree of imposex, as determined by the relative penis size index (RPSI); and the total tin concentration in a sample of dogwhelk tissue were used as measurements of TBT impact on dogwhelk populations. These data were compared with data from a similar survey carried out at the same sites in the Firth of Forth in 1987 (Bailey, S.K., Davies, I.M., 1988. Tributyltin contamination in the Firth of Forth (1975-1987). Science of the Total Environment 76, 185-192.) before restrictions were introduced on the use of TBT. The results demonstrate a general recovery in dogwhelk populations from the impact of TBT at the majority of the sites studied, although at six of the sites, the RPSI value remains high enough to suggest breeding problems in the population. It is suggested that large vessels are responsible for localised cases of imposex within the Firth of Forth.

Leginon: a system for fully automated acquisition of 1000 electron micrographs a day

We have developed a system to automatically acquire large numbers of acceptable quality images from specimens of negatively stained catalase, a biological protein which forms crystals. In this paper we will describe the details of the system architecture and analyze the performance of the system as compared to a human operator. The ultimate goal of the system if to automate the process of acquiring cryo-electron micrographs.

Variations in dose to the extremities of vascular/interventional radiologists

An evaluation was performed to determine the distribution of radiation dose received by vascular/interventional radiologists, hence forth called radiologists, to their hands and arms during interventional radiology procedures. During 87 patient procedures, measurements were made using thermoluminescent dosimeters to determine the distribution of dose to the hands and forearms. Measurements were made on a finger, the palm, wrist, elbow, and the mid-humerus of both hands and arms. Results suggested a non-uniformity of dose with the maximum dose being measured on the left hypothenar (fleshy side of the palm). The left hand receives a higher dose than the right hand due to positioning of the radiologist with respect to the patient.

Molecular characterization of six variant Fcgamma receptor class I (CD64) transcripts

In humans, three distinct but closely related classes of receptors that bind the Fc portion of IgG (FcgammaRI, II and III) have been identified. FcgammaRI can bind monomeric IgG with high affinity and has a unique third extracellular domain (EC3). Three very similar genes have been characterized for FcgammaRI (A, B, C). Although the sequences are remarkably similar, a number of coding-region differences discriminate between the genes and amongst their transcripts. Six distinct FcgammaRI transcripts were analysed. Three transcripts, one from each gene, contain all six exons. Only the gene A transcript appears to encode a bona fide high affinity receptor, a three Ig-domain membrane spanning receptor that can bind monomeric IgG. Stop codons in the EC3 domains of the gene B and gene C isoforms would be predicted to generate secreted receptors. Three transcripts are alternatively spliced isoforms, one from gene A and two from gene B. One gene B transcript encodes a two Ig-domain transmembrane receptor which has structural characteristics of a low affinity FcgammaR.

Diagnosis and radioablation treatment of toxic multinodular goiter in a hemodialysis patient

Toxic multinodular goiter is rare in hemodialysis patients. In addition, establishing the diagnosis of hyperthyroidism in the elderly patient with renal failure is difficult because abnormal thyroid function tests can erroneously be attributed to euthyroid sick syndrome. Treatment of hyperthyroidism in dialysis patients by radioiodine ablation involves careful calculation of 131I dose, determination of interval between 131I administration and its removal by hemodialysis, and minimization of radiation hazards during dialytic removal of 131I. We described the clinical presentation of an elderly dialysis patient with toxic multinodular goiter and discussed our diagnostic and therapeutic approaches. The patient's recovery after 131I ablation was complete and uneventful.

Interleukin-6 production by human neutrophils after Fc-receptor cross-linking or exposure to granulocyte colony-stimulating factor

Polymorphonuclear neutrophils (PMNs) are essential effector cells in host defense and tissue inflammatory responses. These responses may be initiated after cross-linking of cell surface Fc receptors that bind the constant portion of IgG (FcgammaR). We evaluated the effect of cross-linking FcgammaRI or FcgammaRII on interleukin-6 (IL-6) production by purified PMNs from normal donors or from patients being treated with recombinant human granulocyte colony-stimulating factor (rhG-CSF). In PMNs from normal donors, IL-6 mRNA was detected by reverse transcriptase-polymerase chain reaction only after FcgammaRI or FcgammaRII cross-linking. We also found that IL-6 mRNA could be detected in PMNs after either in vitro or in vivo rhG-CSF treatment in the absence of FcgammaR cross-linking. IL-6 protein was found to be produced intracellularly and secreted by PMNs after cross-linking FcgammaRI or FcgammaRII or after rhG-CSF stimulation. Cross-linking FcgammaRI or FcgammaRII on PMNs from patients treated with rhG-CSF resulted in a synergistic increase in IL-6 secretion. Upregulation of IL-6 production by PMNs after rhG-CSF treatment may contribute to a clinical engraftment syndrome that occurs during periods of rapid increase in PMN numbers in patients receiving rhG-CSF.