Electrical impedance tomography effectively used in a case of paediatric pulmonary Langerhans cell histiocytosis

A 2-year-old boy with severe pulmonary Langerhans cell histiocytosis presented in extreme respiratory failure. He was intubated and ventilated. Despite maximal support, he deteriorated and needed extremely high ventilator pressures. An electrical impedance tomography monitor was used to inform management. This is a monitoring technique which is not used in children due to the lack of suitable interface devices and a lack of randomised clinical evidence. Despite technical difficulties, a good signal was achieved. This informed management and enabled the selection of a suitable ventilator strategy, facilitating weaning. Electrical impedance tomography is a viable technology for use in paediatric critical respiratory failure. This is a non-invasive and safe technology which adds individual patient information which is not available through any other modalities. We urge equipment manufacturers to develop belts which will allow routine application of this life-saving technology in children.

Oxygen saturation and haemodynamic changes prior to circulatory arrest: Implications for transplantation and resuscitation

Aims

To describe the progression of oxygen saturations and blood pressure observations prior to death.

Introduction

The progression of physiological changes around death is unknown. This has important implications in organ donation and resuscitation. Donated organs have a maximal warm ischaemic threshold. In hypoxic cardiac arrest, an understanding of pre-cardiac arrest physiology is important in prognosticating and will allow earlier identification of terminal states.

Methods

Data were examined for all regional patients over a two-year period offering organ donation after circulatory death. Frequent observations were taken contemporaneously by the organ donation nurse at the time of and after withdrawal of intensive care.

Results

In all, 82 case notes were examined of patients aged 0 to 76 (median 52, 4 < 18 years). From withdrawal of intensive care to death took a mean of 28.5 min (range 4 to 185). A terminal deterioration in saturations (from an already low baseline) commenced 14 min prior to circulatory arrest, followed by a blood pressure fall commencing 8 min prior to circulatory arrest, and finally a rapid fall in heart rate commencing 4 min prior to circulatory arrest. Two patients had a warm ischaemic time of greater than 30 min; 15 patients had a warm ischaemia time of 10 min or greater; and 53 patients had a warm ischaemia time of 5 min or less. It was observed that 0/82 patients had saturations of less than 40% for more than 3 min prior to cardiac arrest and 74/82 for more than 2 min.

Conclusions

There is a perimortem sequence of hypoxia, then hypotension, and then bradycardia. The heart is extremely resistant to hypoxia. A warm ischaemic time of over 30 min is rare.

Effects of chair vibration on indoor annoyance ratings of sonic booms

The effects of perceptible whole-body vibrations on annoyance ratings of sonic booms and other impulsive environmental sounds experienced indoors were studied. Fifteen pairs of test subjects made annoyance ratings while seated in a living room environment. There were two chairs, one isolated from floor vibrations and the other not isolated, and every test subject rated all signals in both chairs. Halfway through each test session, subjects changed seats. Subjects who sat in the isolated chair first gave lower mean annoyance ratings in both halves of the test than subjects who sat in the non-isolated chair first. Annoyance predictions from models using both sound and vibration measures were closer to average annoyance ratings than predictions from a model using sound measures alone. Reformulation of the annoyance model revealed that the presence of perceptible vibration is equivalent to increasing acoustic metric Perceived Level by 4.8 dB when calculated on exterior signals and by 5.6 dB when calculated on interior signals.

Discovery of ^{72}Rb: A Nuclear Sandbank Beyond the Proton Drip Line

In this Letter, the observation of two previously unknown isotopes is presented for the first time: ^{72}Rb with 14 observed events and ^{77}Zr with one observed event. From the nonobservation of the less proton-rich nucleus ^{73}Rb, we derive an upper limit for the ground-state half-life of 81 ns, consistent with the previous upper limit of 30 ns. For ^{72}Rb, we have measured a half-life of 103(22) ns. This observation of a relatively long-lived odd-odd nucleus, ^{72}Rb, with a less exotic odd-even neighbor, ^{73}Rb, being unbound shows the diffuseness of the proton drip line and the possibility of sandbanks to exist beyond it. The ^{72}Rb half-life is consistent with a 5^{+}→5/2^{-} proton decay with an energy of 800-900 keV, in agreement with the atomic mass evaluation proton-separation energy as well as results from the finite-range droplet model and shell model calculations using the GXPF1A interaction. However, we cannot explicitly exclude the possibility of a proton transition between 9^{+}(^{72}Rb)→9/2^{+}(^{71}Kr) isomeric states with a broken mirror symmetry. These results imply that ^{72}Kr is a strong waiting point in x-ray burst rp-process scenarios.

Environmental impact of coal mining and coal seam gas production on surface water quality in the Sydney basin, Australia

The extraction of coal and coal seam gas (CSG) will generate produced water that, if not adequately treated, will pollute surface and groundwater systems. In Australia, the discharge of produced water from coal mining and related activities is regulated by the state environment agency through a pollution licence. This licence sets the discharge limits for a range of analytes to protect the environment into which the produced water is discharged. This study reports on the impact of produced water from coal mine activities located within or discharging into high conservation environments, such as National Parks, in the outer region of Sydney, Australia. The water samples upstream and downstream from the discharge points from six mines were taken, and 110 parameters were tested. The results were assessed against a water quality index (WQI) which accounts for pH, turbidity, dissolved oxygen, biochemical oxygen demand, total dissolved solids, total phosphorus, nitrate nitrogen and E .coli. The water quality assessment based on the trace metal contents against various national maximum admissible concentration (MAC) and their corresponding environmental impacts was also included in the study which also established a base value of water quality for further study. The study revealed that impacted water downstream of the mine discharge points contained higher metal content than the upstream reference locations. In many cases, the downstream water was above the Australia and New Zealand Environment Conservation Council and international water quality guidelines for freshwater stream. The major outliers to the guidelines were aluminium (Al), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn). The WQI of surface water at and downstream of the discharge point was lower when compared to upstream or reference conditions in the majority of cases. Toxicology indices of metals present in industrial discharges were used as an additional tool to assess water quality, and the newly proposed environmental water quality index (EWQI) lead to better trend in the impact of coal and coal seam gas mining activities on surface water quality when compared to the upstream reference water samples. Metal content limits were based on the impact points assigned by the Agency for Toxic Substances and Disease Registry, USA. For environmental and health impact assessment, the approach used in this study can be applied as a model to provide a basis to assess the anthropogenic contribution from the industrial and mining activities on the environment.

Attitudes towards fever amongst UK paediatric intensive care staff

The role played by fever in the outcome of critical illness in children is unclear. This survey of medical and nursing staff in 35 paediatric intensive care units and transport teams in the United Kingdom and Ireland established attitudes towards the management of children with fever. Four hundred sixty-two medical and nursing staff responded to a web-based survey request. Respondents answered eight questions regarding thresholds for temperature control in usual clinical practice, indications for paracetamol use, and readiness to participate in a clinical trial of permissive temperature control. The median reported threshold for treating fever in clinical practice was 38 °C (IQR 38-38.5 °C). Paracetamol was reported to be used as an analgesic and antipyretic but also for non-specific comfort indications. There was a widespread support for a clinical trial of a permissive versus a conservative approach to fever in paediatric intensive care units. Within a trial, 58% of the respondents considered a temperature of 39 °C acceptable without treatment.

CONCLUSIONS

Staff on paediatric intensive care units in the United Kingdom and Ireland tends to treat temperatures within the febrile range. There was a willingness to conduct a randomized controlled trial of treatment of fever. What is known: • The effect of fever on the outcome in paediatric critical illness is unknown. • Paediatricians have traditionally been reluctant to allow fever in sick children. What is new: • Paediatric intensive care staff report a tendency towards treating fever, with a median reported treatment threshold of 38 °C. • There is widespread support amongst PICU staff in the UK for a randomized controlled trial of temperature in critically ill children. • Within a trial setting, PICU staff attitudes to fever are more permissive than in clinical practice.

Pressure-related flow rates for continuous renal replacement therapy in very small children: an in vitro study

OBJECTIVE

Continuous renal replacement therapy (CRRT) is extremely challenging in very small children, as most CRRT intravascular access devices are too large. We aimed to quantify flow rates through several alternative intravascular devices.

DESIGN

Experimental in vitro study simulating CRRT.

SETTING

Whole milk and equine blood were used as human blood substitutes due to similar viscosity. Milk under gravity pressure was run through a standard CRRT circuit. Equine blood was run through a working CRRT machine.

SUBJECTS

Eight intravenous access devices used in paediatrics, with a variety of connectors.

INTERVENTIONS

Devices were tested with milk for flow between 50 and 200 mm Hg pressure, and with blood for pressure at flows between 20 and 50 mL/min.

MAIN OUTCOME MEASURES

Flows at each input pressure with milk, and pressures at each flow rate with blood.

RESULTS

With both experimental systems, 8Fr and 6.5Fr haemodialysis catheters, and 18G and 20G cannulae allowed excellent low pressure flow rates. 5Fr triple central catheter, 5Fr and 4Fr umbilical venous catheter, and 5Fr haemodialysis catheters did not allow flows at reasonable pressures for CRRT. A three-way tap did not impede flows, but a needle-free valve did. Flows increased with pressure non-linearly, presumably due to increasing turbulence.

CONCLUSIONS

In very small patients needing CRRT, where large haemodialysis catheters cannot be used due to the patient size, we advise the use of two 18G cannulae in different sites. A three-way tap can be added, but not any other connectors. In vitro this system gave suitable flow rates with some flexibility for in vivo variations.

A Delphi Survey of Best Practice Occupational Therapy for Parkinson's Disease in the United Kingdom

This study was designed to determine the character of best occupational therapy practice for Parkinson's disease in the United Kingdom. Two hundred and forty-two occupational therapists treating people with Parkinson's disease were sent a Delphi survey containing statements about best practice and asked to indicate their level of agreement with each statement. The second survey contained the same list of statements, with group levels of agreement from the first round for each statement. The respondents re-rated their answers and gave their opinion on the efficacy of various interventions.

One hundred and fifty occupational therapists (62%) completed both rounds. Ninety-nine per cent of the respondents agreed that Parkinson's disease required lifelong provision of occupational therapy, within multidisciplinary teams, and that the social and psychological aspects of the disease were as important as the physical ones. The occupational therapists had confidence in many techniques for achieving physical, social and psychological goals. However, 40% of the respondents could not rate the efficacy of social and psychological techniques owing to a lack of knowledge.

There was a high level of consensus nationally on the character of best practice occupational therapy for Parkinson's disease. The survey highlighted a need for more postgraduate training, especially in psychological techniques.

A Survey of Current Occupational Therapy Practice for Parkinson's Disease in the United Kingdom

Little is known about the current character of occupational therapy practice for Parkinson's disease in the United Kingdom. The study aimed to document this in order to inform plans for a future multicentre randomised controlled trial.

Two hundred and forty-two occupational therapists that treated people with Parkinson's disease were sent a questionnaire regarding demographics, service organisation and therapy content. One hundred and sixty-nine occupational therapists (70%) responded. They had worked with people with Parkinson's disease for a median of 6 years and personally treated a median of 15 people with Parkinson's disease annually. Most (86%) were at senior grade or above; 87% worked in the National Health Service and 12% in social services. Forty per cent worked in specialist Parkinson's disease clinics. Most (79%) felt that they needed more specialist postgraduate training.

Occupational therapists are employed in both health and social care settings. The character of the occupational therapy is often determined by the location in which it is provided. Current occupational therapy appears to focus on functional activities rather than on the wider social and psychological aspects of occupation. Many occupational therapists felt that they needed more specialist postgraduate training to treat people with Parkinson's disease effectively.

Deep Brain Stimulation for Neuropathic Cephalalgia

The aim of this study was to determine the efficacy of deep brain stimulation (DBS) in the treatment of various types of intractable head and facial pains. Seven patients underwent the insertion of DBS electrodes into the periventricular/periaqueductal grey region and/or the ventroposteromedial nucleus of the thalamus. We have shown statistically significant improvement in pain scores (visual analogue and McGill's) as well as health-related quality of life (SF-36v2) following surgery. There is wide variability in patient outcomes but, overall, DBS can be an effective treatment. Our results are compared with the published literature and electrode position for effective analgesia is discussed.

Effects of Movements upon the Appearance and Duration of a Prolonged Visual Afterimage: 2. Changes Arising from Movement of the Observer in Relation to the Previously Afterimaged Scene

Gregory et al. (1959) reported that visual afterimages undergo changes in appearance when the observer moves. Davies in part 1 of this series reported qualitative and quantitative effects upon the appearance and duration of afterimages when a portion of the body incorporated in the afterimaged scene was moved. This paper reports an experiment in which 12 subjects afterimaged a long narrow corridor before (a) standing still and observing the afterimage; (b) turning right or left through 90 degrees and observing; and (c) walking along the afterimaged corridor. Each task was performed 5 times in a counterbalanced order by each subject. The timed observation period was from the flash to the termination of the long positive afterimage. Subjects reported qualitative changes in the appearance of the afterimage when observing it after turning right or left or during walking. The duration of the afterimage was also greater in those experimental conditions involving movement than in the condition involving immobile observation.

Effects of Movements upon the Appearance and Duration of a Prolonged Visual Afterimage: 1. Changes Arising from the Movement of a Portion of the Body Incorporated in the Afterimaged Scene

Gregory et al. (1959) reported qualitative changes in the appearance of a prolonged visual afterimage (viewed in total darkness) which arise from body movements. This paper (part 1 of a two part series) reports an experiment in which 12 subjects were required to observe an afterimage (in total darkness) of no, one, or both of their hands against a simple background. Movement of the hands during the observation period gave rise to qualitative changes in the appearance, and quantitative changes in the duration, of the afterimage. The former were confined to the portion of the afterimage corresponding to the moved hand, and the duration of the afterimage increased with the more complex changes in the scene. As kinaesthetic and proprioceptive information that conflicts with the visual input affects both the duration and the appearance of the afterimage, the data offer some support for the hypothesis that the duration and appearance of a visual afterimage may not be solely dependent upon retinal processes.

Observational study of children admitted to United Kingdom and Republic of Ireland Paediatric Intensive Care Units after out-of-hospital cardiac arrest

AIMS

To estimate the prevalence of children admitted after out-of-hospital cardiac arrest (OHCA) to UK and Republic of Ireland (RoI) Paediatric Intensive Care Units (PICUs) and factors associated with mortality to inform future clinical trial feasibility.

METHOD

Observational study using a prospectively collected dataset of the Paediatric Intensive Care Audit Network (PICANet) of 33 UK and RoI PICUs (January 2003 to June 2010). Cases (0 to <16 years), with documented OHCA surviving to PICU admission and requiring mechanical ventilation were included. Main outcomes were prevalence for admission and death within PICU. Factors associated with mortality were examined with multiple logistic regression analysis.

RESULTS

827 of 111,170 admissions (0.73%; 95% CI [0.48 to 0.98%]) were identified as children admitted following OHCA. PICU mortality for OHCA was 50.5% (418/827). Recruitment into an adequately sized clinical trial would not be feasible with the current prevalence rate. Characteristics at PICU admission associated with increased risk of death included; bilateral unreactive pupils, genetically inherited condition, inter-hospital transfer to PICU, requirement for vasoactive drugs and greater base deficit. Factors associated with reduced risk of death were submersion or a respiratory aetiology and pre-existing respiratory or cardiac conditions.

CONCLUSIONS

Less than 120 children a year are admitted to PICUs in the UK and RoI after OHCA, limiting options for conducting UK intervention trials. The risk factors associated with mortality identified in this study will allow risk stratification in future studies.