Beds In Use Research Articles

Complexity measure based on sensitivity analysis applied to an intensive care unit system

This work proposes a system complexity metric and its application to Intensive Care Unit (ICU) system. The methodology for applying said complexity metric comprises: (i) parameters sensitivity indices calculation, (ii) mapping connections dynamics between system components, and (iii) system’s complexity calculation. After simulating the ICU computer model and using the proposed methodology, we obtained results regarding: number of admissions, number of patients in the queue, length of stay, beds in use, ICU performance, and system complexity values (in regular or overloaded operation). As the number of patients in the queue increased, the ICU system complexity also increased, indicating a need for policies to promote system robustness.

Parents’ comfort and staffs’ working-environment when infants are sitting skin-to-skin: a randomised controlled trial comparing a recliner and a hospital bed

Skin-to-skin contact between parents and preterm infants is recommended because it has proven to be valuable for the infants’ development and healing. However, it can be difficult to comply with this guideline and still ensure a good working environment for the staff. This randomised controlled trial compared a new recliner developed in collaboration with parents and staff with a hospital bed for use in neonatal and maternity care using parents’ rating of own comfort/discomfort, self-reliance, and felt security, and the chair’s/bed’s functionality at two different days (Q1 and Q2) of hospitalisation. The physical work-environment was evaluated through a questionnaire to the staff. Ninety-seven parents and 53 health professionals participated. Parents had significantly lower discomfort, in the recliner at Q1 compared to the hospital bed. The staff had to twist and/or bend their back significantly less often when working at the recliner as compared to the hospital bed. Practitioner summary: Due to poor working environment, a participatory design project developed a new recliner that improved the possibility of infants having skin-to-skin contact with their parents. The recliner provided a better working-environment for the staff while focussing on improving comfort and self-reliance of the parents, as compared to a hospital bed. Abbreviations: NICU: Neonatal Intensive Care Unit; VELA: Vermund Larsen

Vibrational Microfeeding of Polymer and Metal Powders for Locally Graded Properties in Powder-Based Additive Manufacturing

Subject of this work is the contact mechanical properties and flowability of polymer and metal powders when they are dispensed on the surface of a powder bed for use in laser-based powder bed fusion in additive manufacturing. Generating local part properties in metal as well as polymer-based powder bed fusion processes is of high interest, so an approach is made to locally add additives by a vibrational microfeeding system for metal and polymer powders. To realize a controlled powder discharge, the behavior of additives, which are dropped on a surface and on a powder bed is analyzed. Influencing factors for mass flow of the powders will be excitation frequency, excitation amplitude and capillary diameter on the side of experimental setup as well as particle size distribution and physical properties on the material side.

Chitosan‐Coated Glass Beads in a Fluidized Bed for Use in Fixed‐Bed Dye Adsorption

AbstractThe effects of the inlet air temperature and two chitosan solutions, pure or with coating auxiliaries, on the coating efficiency of glass beads in a fluidized bed were analyzed. The coated beads were used in a fixed‐bed column for adsorption of reactive black 5 dye in aqueous solution, and the effects of the pH and the coating solution formulation on the adsorption capacity were investigated. The glass bead coating process reached higher efficiencies at an air temperature of 80 °C with pure chitosan solution. The highest adsorption capacities were found at pH 3, using the beads coated with pure chitosan solution. All dynamic adsorption models were suitable to represent the breakthrough curves. The high values found for the coating efficiency and adsorption capacity prove these methods to be promising in dye adsorption.

Alternative drying of orange bagasse in vibrofluidized bed for use in combustion

Orange is one of the most consumed fruits in the world, part of the production is directed to the production of industrialized juice that generates the orange bagasse. Initially, it was evaluated the influence of virgin and hydrated CaO pre-treatment on the mechanical dewatering stage and on the thermal drying in the vibrofluidized bed. In the mechanical dewatering stage, humidity reduction from 1 to 0.6 (dimensionless) was obtained, probably because of the interaction between the adsorbed water of pectin molecules and the CaO. No significant variations were identified in the type of CaO used in this step, however, the increase in virgin CaO content led to an increase in the flow of the removed moisture. The drying kinetics of the pressed waste in vibrofluidized bed were analyzed with vibration amplitude and frequency of 0.015 m and 6.16 Hz, respectively, at 70 and 80 °C, where the humidity was reduced to approximately 0.1 and only decreasing rate period was identified. The drying kinetics compared the influence of CaO pre-treatment under different conditions and in general the use of CaO improved the drying process. The dry waste was also characterized, where it was identified high higher heating value (HHV) and high volatile matter.

Polarity Induced in Human Stem Cell Derived Motoneurons on Patterned Self-Assembled Monolayers.

The control of polarized human neurite/axon development at the single neuron level is critical in geographically directing signal propagation in engineered neural networks, for both in vitro and in vivo applications. While there is an increasing need to exert control over axonal growth for the successful development and establishment of integrative and functional in vitro systems, controlled, polarized distribution of either human-derived neurons or motoneurons in vitro has yet to be reported. In this study, we established the polarized distribution of stem cell derived human motoneurons, using a patterned surface, and maintained the cells in a serum-free system. A surface pattern with defined polarity was developed using self-assembled monolayers (SAMs). A cell permissive SAM, DETA (trimethoxysilyl propyldiethylenetri-amine), combined with photolithography and a nonpermissive fluorinated silane, 13F (tridecafluoro-1,1,2,2-tetrahydroctyl-1-dimethylchloro-silane), generated a surface where neurons only adhered to the designed attachment sites and did so with preferred orientation. In addition, 75% of the cells attached to the patterns were motoneurons compared to their percentage in the standard unpatterned surface which was used as a control condition (20%), demonstrating the preference of these human motoneurons in adhering to the patterns. The ability to dictate the distribution and polarity of human motoneurons will be essential to the engineering of human-based functional in vitro systems in which the control of signal propagation is necessary but more importantly for cell implantation studies. Such systems will greatly benefit the study of motor function as well as aid the development of high-throughput systems for drug screening and test beds for use in preclinical studies related to conditions such as spinal cord injury, ALS, and muscular dystrophy.

Structure and function of a trauma intensive care unit: A report from the Trauma Intensive Care Unit Prevalence Project.

Specialized trauma intensive care unit (TICU) care impacts patient outcomes. Few studies describe where and how TICU care is delivered. We performed an assessment of TICU structure and function at a sample of US trauma center TICUs. This was a multicenter study in which participants supplied information about their trauma centers, staff, clinical protocols, processes of care, and study TICU (the ICU admitting the majority of trauma patients). Forty-five Level I trauma centers trauma centers enrolled through the American Association for the Surgery of Trauma multi-institutional trials platform; 71.1% had less than 750 beds and 55.5% treated 1,000 to 2,999 trauma activations/year. The median number of hospital ICU beds was 109 [66-185]. 46.7% were "closed" ICUs, 20% were "open," and 82.2% had mandatory intensivist consultation. 42.2% ICUs were classified as trauma (≥80% of patients were trauma), 46.7% surgical/trauma, and 11.1% medical-surgical. Trauma ICUs had a median 10 [7-12] intensivists. Intensivists were present 24 hours/day in 80% of TICUs. Centers reported a median of 8 (interquartile range [IQR], 6-10) full-time trauma surgeons, whose ICU duties comprised 25% (IQR, 20%-40%) of their clinical time and 20% (IQR, 20-33) of total work time. A median 16 (IQR, 12-23) ICU beds in use were staffed by 10 (IQR, 7-14) nurses. There was considerable variation in the number and type of protocols used and in diagnostic methods for ventilator-associated pneumonia. Daily patient care checklists were used by 80% of ICUs. While inclusion of families on rounds was performed in 91.1% of ICUs, patient- and family-centered support programs were less common. A study of structure and function of TICUs at a sample of Level I trauma centers revealed that presence of nontrauma patients was common, critical care is a significant component of trauma surgeons' professional practice, and significant variation exists in care delivery models and protocol use. Opportunities may exist to improve care through sharing of best practices. Therapeutic/Care management, level IV.

Fluidization in small-scale gas-solid 3D-printed fluidized beds

Additive manufacturing could be used to facilitate the rapid fabrication and testing of small-scale fluidized beds for use in screening applications, such as adsorbent screening for carbon capture. In this work, experiments were performed in order to map the different flow regimes produced in small-scale (Dh = 3–15 mm) gas-solid fluidized beds that were fabricated using additive manufacturing using the stereolithography approach. Here, the effects of bed hydraulic diameter (Dh), static particle height (Hs), and particle type/size (Dp and ρp) were considered. Pressure drop data and high speed camera images were used to develop simple flow regime maps for these printed beds showing the operating windows for packed bed, bubbling, slugging and turbulence applicable to a wide range of bed size to particle diameter ratios (Dh/Dp = 20–200) and gas velocities (Ug = 1–400 mm/s) in both ‘2D’ and ‘3D’ bed aspect ratios. Fast Fourier transforms of the pressure drop signals were also used to study the evolution of bubbling/slugging behaviour as the gas velocity was increased by creating 2D colour maps of the frequency spectra. These allowed a new quantitative method to be proposed for the identification of slugging – the point where the dominant frequency in the power spectrum becomes constant as the gas velocity increases. It is concluded in this study that the rougher surfaces generated by additive manufacturing do not influence the fluidization characteristics nor modify the wall effects of small-scale beds. Macro-scale fluidization could also be achieved at smaller Dh/Dp ratios in these 3D printed beds compared to more conventional Plexiglas beds (Dh/Dp = 75 compared to Dh/Dp = 300).

Performance evaluation of a new modular packed bed for adsorption cooling systems

A newly designed packed bed for use in adsorption cooling (AC) systems is evaluated in this research. The bed is modular and can be scaled for a given cooling load. An experimental setup is built to measure the adsorption kinetics of one module under typical operating conditions. Also, a transient three-dimensional local thermal non-equilibrium model (LTNE) is developed to study the heat and mass transfer inside the packed bed. Darcy’s equation and linear driving force model are solved simultaneously to account for inter-particle and intra-particle mass transfer, respectively. Silica gel RD-2060 and advanced zeolite AQSOA-Z02 are chosen as an adsorbent for the packed bed. Good agreement between the experimental measurements and numerical results is established. The effects of operating conditions on the specific cooling power (SCP) produced by the two different working pairs are investigated. The results show that silica gel RD-2060 yields higher SCP than zeolite AQSOA-Z02 for the same operating conditions. For AQSOA-Z02/water, the bed performance is insensitive to changes in the convective heat transfer coefficient because the overall bed thermal resistance is dominated by the adsorbent low thermal conductivity. The proposed modular bed produces an SCP of 460 W/kg of silica gel at operating conditions of 10 °C chilled water temperature, 30 °C condenser temperature and 95 °C regeneration temperature, which is 2.3 times higher than the SCP for typical finned-tube adsorption chillers.

Performance Study of a Novel Solar Solid Dehumidification/Regeneration Bed for Use in Buildings Air Conditioning Systems

In this paper, a novel solar solid dehumidification/regeneration bed has been proposed, and its three regeneration methods, i.e., simulated solar radiation regeneration, microwave regeneration, and combined regeneration of the microwave and simulated solar radiation, were experimentally investigated and compared, as well as the dehumidification performance. The degree of regeneration of the proposed system under the regeneration method combining both microwave irradiation and simulated solar radiation could reach 77.7%, which was 3.77 times higher than that of the system under the simulated solar regeneration method and 1.05 times higher than that of the system under the microwave regeneration. The maximum energy efficiency of the proposed system under the combined regeneration method was 21.7%, while it was only 19.4% for the system under microwave regeneration. All these proved that the combined regeneration method of the simulated solar and microwave radiation not only improved the regeneration efficiency of the system, but also enhanced the energy efficiency. For the dehumidification performance, the maximum transient moisture removal was 14.1 g/kg, the maximum dehumidification efficiency was 68.0% and the maximum speed of dehumidification was 0.294 g/(kg·s) when the inlet air temperature was at 26.09 °C and the air relative humidity was at 89.23%. By comparing the testing results with the semi-empirical results from the Page model, it was indicated that the Page model can predict the regeneration characteristics of the novel solar solid dehumidification/regeneration bed under the combined method of microwave and simulated solar regeneration. The results of this research should prove useful to researchers and engineers to exploit the potential of solar technologies in buildings worldwide.

Improving hospital bed utilisation through simulation and optimisation: With application to a 40% increase in patient volume in a Norwegian general hospital

PurposeThis paper analyses the problem of allocating beds among hospital wards in order to minimise crowding. MethodWe present a generic discrete event simulation model of patient flow through the wards of a hospital. In the generic model, each ward can have separate probability distributions for arrival times and length of stay, which may be time dependent. Output of the model is a matrix, with statistics on the utilisation of different hypothetical numbers of beds for each ward. This matrix is fed into an allocation algorithm, which distributes the available beds among the wards in an optimal way. We define bed utilisation either in terms of how often it is in use (prevalence), or in terms of how often a newly arriving patient is placed in it (incidence). For these classes of utilisation measures we develop efficient allocation algorithms, which we prove to be optimal. ApplicationThe model was applied to Akershus University Hospital in Norway. In 2011, some of the wards of this hospital experienced a high occupancy rate, while others had a lower utilisation. Our model was applied in order to reallocate the hospital beds among the wards. For each ward, acute arrivals were modelled with Poisson-distributions with time-varying intensity, while elective arrivals were programmed to arrive in specific numbers at specific times. The arrival rates were based on empirical data for 2010, scaled up by an expected increase of 40% due to a restructuring of the hospital districts in Oslo and the greater metropolitan area in 2011. Length of stay was modelled as beta-distributions, using a combination of subject matter experts’ evaluations and empirical data from 2010. The model has been verified and validated. ResultsIntuitively, both prevalence (average number of crowding beds in use) and incidence (number of patients placed in crowding beds) might seem like relevant optimisation criteria. However, our experiments show that prevalence optimisation gives more sensible solutions than incidence optimisation, as the latter tends to sacrifice entire wards where length of stay is long and patient turnover is slow. Prevalence optimisation was therefore used. The main results show that when the bed distribution is optimised, the share of crowding patient nights is reduced from 6.5% to 4.2%. ConclusionThis model provides a powerful tool for optimising hospital bed utilisation, and the application showed an important reduction in crowding bed usage. The generic model is flexible, as the level of detail in the modelling of arrivals and length of stay can vary according to the data available and accuracy required.

Technical Note: Feasibility of Extracting Ammonia from Broiler Litter and Scale-Up Considerations

Air inside the broiler litter bed has high ammonia concentrations. The feasibility of extracting ammonia from the broiler litter bed for use as a fertilizer was investigated. Suction was applied to six -in. (12.7-mm) CPVC pipes with perforations placed 0.15 m below the litter surface in a pen stocked with 150 birds. Litter air was pulled into a phosphoric acid reactor where the ammonia was converted to ammonium phosphate, a fertilizer. Over 51 d, 72.6 g of ammonia was recovered and the pipes did not clog. Ammonia recovery could have been higher had litter ammonia concentrations been comparable with commercial broiler houses. Ammonia removal from the pen did not impact ammonia concentrations above the litter or bird performance. Placing the pipes close to the litter surface where total ammoniacal nitrogen concentrations would have been higher due to fecal loading may have reduced ammonia concentrations in the pen. Litter moisture content was reduced by the ammonia extraction system. A modified scaled-up system may be technically feasible but not cost-effective. Economic feasibility of the system can be improved if pipes placed closer to the surface improve bird performance by reducing in-house ammonia concentrations.

Acute hospitalisation needs of adults admitted to public facilities in the Cape Town Metro district.

Public health care delivery in South Africa aims to provide equitable access at the most appropriate level of care. We studied to what extent the acute health care needs of adults admitted to public hospitals in the Cape Town Metropole were being appropriately met. A retrospective study was conducted of the hospital records of adults admitted to medical beds in public hospitals in Cape Town between August and November 2008. Intensive care unit patients were not included. Of 802 beds in use, the estimated occupancy was at least 95%. The average time elapsed since admission was 7.9 days; 94.3% of medical admissions were acute; 45% were severely to critically ill on admission; and co-morbid disease was present in 78.1%. Of all admissions, 31.9% were HIV-positive, and 17% had active tuberculosis. At least 396 (51.6%) patients were deemed to have required specialist or subspecialist consultation to expedite appropriate care; 386 (50.3%) accessed the appropriate level of medical care required; 339 (44.2%) accessed a more sophisticated level of care than required; and 42 (5.5%) did not access an adequate level of care. CT scan and ultrasound accounted for 59% of all restricted tests done. Our findings support the plan to provide more primary care hospital facilities in the metropolitan area. Most patients needing specialised care are accessing such care, and most patients accessing a higher level of care than needed can be addressed by ensuring that they first access primary care and are referred according to protocols.

Global Challenges in Stem Cell Research and the Many Roads Ahead

The field of stem cell research has grown to include a vibrant international community of scientists and clinicians who come from both academia and industry and who strive to shed light on the biology of these remarkable cells and find applications in drug discovery, disease modeling, and regenerative medicine.

Image based meshing of packed beds of cylinders at low aspect ratios using 3d MRI coupled with computational fluid dynamics

CFD is a valuable tool for understanding the flow and pressure drop in packed beds. However, determining the geometry can be complex. One possible method is to use a non-invasive imaging method such as MRI, however, problems occur in processing complex geometries when using traditional commercial meshing software. This work focuses on the use of image based meshing software originally developed for the field of computational biomechanics, to create geometries from 3d MRI scans of packed beds for use with computational dynamics. For this work we focus on disordered packed beds of cylinders at low aspect ratios and Reynolds numbers of Re = 1431–5074 (based on particle diameter and superficial velocity). We compare CFD studies with experimental data performed on the actual scanned beds and compare these with the correlation proposed by Eisfeld and Schnitzlein (2001). Computational data is shown to correlate well with experimental and theoretical results.

Multipronged Intervention Strategy to Control an Outbreak of Clostridium difficile Infection (CDI) and Its Impact on the Rates of CDI from 2002 to 2007

At the end of 2002, a new, more virulent strain of Clostridium difficile, designated BI/NAP1, was the cause of a massive outbreak of infection in the province of Quebec. This particular strain was associated with a dramatic increase in morbidity and mortality among affected patients in 2003-2004. We tested and implemented a multipronged infection control approach to curtail the rate of C. difficile infection (CDI). Five-year observational study. A 554-bed, acute care tertiary hospital, the largest single medical center in Quebec, Canada. To curtail the magnitude of the outbreak, we implemented a global strategy consisting of rapid C. difficile testing for all hospitalized patients who had at least 1 occurrence of liquid stool, the rapid isolation of patients infected with C. difficile in a dedicated ward with a specially trained housekeeping team, a global hand hygiene program, and the hiring of infection control practitioners. Antibiotic consumption at the institutional level was also monitored during the 5-year surveillance period. Cases of hospital-acquired CDI per 1,000 admissions were continuously monitored on a monthly basis during the entire surveillance period. The highest recorded CDI rate was 42 cases per 1,000 admissions in January 2004. Once additional infection control resources were put in place, the rate decreased significantly during the period from April 2005 to March 2007. During the 2003-2004 period, there were 762 cases of CDI (mean annual rate, 37.28 cases per 1,000 admissions) recorded in our study, compared with 292 cases of CDI (14.48 cases per 1,000 admissions) during the 2006-2007 period (OR, 0.379 [95% CI, 0.331-0.435]; p< .001), a 61% reduction. In March 2007, the equivalent of 4 full-time equivalent infection control practitioners were in place, which gave a ratio of 0.96 infection control practitioners per 133 beds in use, compared with the ratio of 0.24 infection control practitioners per 133 beds in use in 2003, and the total number of hours dedicated to cleaning and housekeeping increased by 26.2%. The total amount of antibiotics used in the hospital did not vary significantly from 2002 to 2007, although there were changes in the classes antibiotic used. The implementation of a multipronged intervention strategy to control the outbreak of CDI significantly improved the overall situation at the hospital and underlined the importance of investing in stringent infection control practices.

Do Hospital Bed Reduction and Multiple System Reform Affect Patient Mortality?

The impact of hospital and system restructuring on the quality and pattern of care is an important issue of public policy concern. To assess the effect on patterns of care and patient outcomes of a substantial reduction in public hospital bed availability and multiple reorganizations in New Zealand through the 1990s. Trend analysis using both tabular and multilevel techniques. Access to discharge data, amounting to 6,639,487 records, was secured for all 34 major public hospitals in New Zealand over the period 1988-2001. Number of discharges, admission rate, access levels, mean length of stay, unplanned readmission rate, and 60-day postadmission mortality rate. Although the number of inpatient beds in use declined by one-third over the period and the national population grew by nearly one-fifth, discharge volumes increased significantly and rates of inpatient admission were maintained, as were access levels for vulnerable groups. These changes were accompanied by workload adjustments (a halving in length of stay and an increase by a quarter in readmission rates). Yet age-adjusted postadmission patient mortality decreased by a quarter over the period of study, a rate of decline that was slowed by the major workload adjustments but not by reform phase. Other things being equal, a substantial reduction in inpatient bed availability can be effected in national public hospital systems, while largely maintaining access and quality of care. However, the workload adjustments that are required may slow improvements in patient outcomes.

Influence of decelerating flow on incipient motion of a gravel-bed stream

An experimental study on incipient motion of gravel-bed streams under steady-decelerating flow is presented. Experiments were carried out in a flume with two median grain sizes, d 50 = 16.7 mm for a fixed-bed case and d 50 = 8 mm for a mobile bed case. In addition, an effort is made to determine a simplified method for the estimation of bed shear stress in decelerating flow over fixed and mobile beds for use in field situations. From the observation of eleven fixed-bed and nine mobile-bed velocity profiles, it is revealed that the parabolic law method (PLM) and the Reynolds stress method are comparable for estimation of shear velocity in general. Also, the results show that the shear stress distribution adopts a convex form over fixed and mobile beds. Due to this form the critical Shields parameter value for decelerating flow is less than the reported values in literature.This paper supports Buffington & Montgomery (1997) statement that less emphasis should be given on choosing a universal shields parameter, and more emphasis should be given on choosing defendable values based on flow structure.

A sorption compressor with a single sorber bed for use with a Linde–Hampson cold stage

A sorption compressor cell basically consists of a container that is filled with an adsorbent. When such a cell is thermally cycled, a pressure difference is created by the subsequent adsorption and desorption of the gas. As a consequence, a single sorption compressor cell inherently provides an intermittent flow. A Joule–Thomson expansion stage requires a more or less continuous flow. The standard way to obtain a continuous flow out of a sorption compressor is to use three or more compressor cells that are operated out of phase. This paper presents an alternative compressor concept that uses only one compressor cell, two buffer volumes and two check valves. Such a compressor is easier to construct and to operate and has a higher reliability at the expense of a slight variation in the cooler’s cold-end temperature. The principle was demonstrated using a sorption compressor cell that is filled with Maxsorb [The Kansai Coke & Chemicals Co. Ltd., 1-1 Oh-Hama, Amagasaki, Japan 660] activated carbon, is equipped with a gas-gap heat switch, and uses xenon as the working fluid. A flow of 0.52 mg/s was achieved with a low pressure of 1.39 bar and a high pressure of 17.0 bar, giving a theoretical cooling power of 42 mW at 172 K. A sensitivity analysis on several control parameters has been performed experimentally.

Breast-conserving Surgery with Intra-operative Radiotherapy: The Right Approach for the 21st Century?

Wide local excision followed by external beam radiation therapy (EBRT) to the whole breast has become the standard of care for most patients with localised ‘early’ breast cancer in the UK, Europe, and the USA. Local relapse rates are low, and overall survival figures have improved during the past decade, with the advent of more effective systemic endocrine- and chemo-therapy. A policy of EBRT for every patient undergoing breast conserving surgery (BCS) is however associated with a number of practical difficulties, acute radiation side effects and longer term toxicity, all of which detract from the obvious benefits of EBRT. In addition, with a disease as common as early breast cancer and a treatment programme typically requiring sophisticated radiation planning and many fractions of treatment, the policy of BCS plus EBRT has enormous resource implications within departments of oncology, greatly contributing to lengthy pre-treatment delays. For all these reasons, we and others have developed an increasing interest in techniques of partial breast irradiation, with an emphasis in our own Department on the emerging technique of intra-operative radiotherapy (IORT), which we initially employed as a boost to the tumour bed for use in conjunction with EBRT to the whole breast. To test the possibility of replacing the whole of the EBRT 3–6 week programme by a single application of IORT at the time of surgery, we and others have commenced a large scale prospectively randomised clinical trail in selected patients. Nine international centres are currently participating, and 350 patients have now been randomised to receive either IORT as part of the initial surgical excision or conventional EBRT with a pragmatic dose policy according to the preference of the contributing centre. The majority of patients undergoing IORT receive this at the time of initial surgery but it is also permissible within the trial programme to randomise suitable patients after the excised specimen has been histologically examined, thus avoiding any unsuitable patients — for example, those with a lobular carcinoma. These patients will be stratified and assessed separately from the ‘pre-pathology’ group, whose surgery and IORT is completed within a single session; if the latter patients are found to have unfavourable histology we have the facility, within the trial, to add EBRT. The trial is ongoing and our early experience has been encouraging. We have also recently assessed the long term local failure rate in patients offered IORT as a tumour bed boost, in conjunction with conventional EBRT. This methodology will also be the subject of a future randomised clinical trial.