Technology and Health Care - Volume 19, issue 1

Authors: Kumar, Sameer

Article Type: Research Article

Abstract: Objectives: It is increasingly recognized that hospital operation is an intricate system with limited resources and many interacting sources of both positive and negative feedback. The purpose of this study is to design a surgical delivery process in a county hospital in the U.S where patient flow through a surgical ward is optimized. Method: The system simulation modeling is used to address questions of capacity planning, throughput management and interacting resources which constitute the constantly changing complexity that characterizes designing a contemporary surgical delivery process in a hospital. Results: The steps in building a …system simulation model is demonstrated using an example of building a county hospital in a small city in the US. It is used to illustrate a modular system simulation modeling of patient surgery process flows. Conclusions: The system simulation model development will enable planners and designers how they can build in overall efficiencies in a healthcare facility through optimal bed capacity for peak patient flow of emergency and routine patients. Show more

Keywords: System simulation modeling, hospital planning, health service, patient flow, process analysis, operations research

DOI: 10.3233/THC-2011-0607

Citation: Technology and Health Care, vol. 19, no. 1, pp. 1-20, 2011

Authors: Jack, L.P. | Purcell, M. | Allan, D.B. | Hunt, K.J.

Article Type: Research Article

Abstract: Background: We are investigating the potential of robotics-assisted treadmill technology as a mode of exercise in people with spinal cord injury (SCI). People with incomplete SCI can actively contribute to this form of exercise, but in the clinical setting they often walk passively in the system. It is not known whether in doing so they are meeting the recommended guidelines for increasing cardiopulmonary fitness. Objective: The aims of this study were twofold: to characterise the intensity of passive walking during robotics-assisted treadmill exercise (RATE) in incomplete SCI; and to determine if this intensity meets the recommended guidelines …for cardiopulmonary training in this population. Methods: 10 subjects with incomplete SCI twice performed an exercise test on a robotics-assisted treadmill. The test comprised a period of passive walking and a ramp phase to the limit of tolerance. Oxygen uptake (V̇O2 ) and heart rate (HR) were continuously measured. Results: V̇O2 during passive exercise was on average 1.4 times higher than resting V̇O2 (V̇O2R ), but this was only 29% of peak V̇O2 (V̇O2peak ) (range 16–43%). Relative to rest, passive V̇O2 (V̇O2P ) was only 12% of V̇O2 (V̇O2peak ). HR did not increase from rest to passive walking (81 ± 10 bpm to 81 ± 13 bpm respectively). The HR associated with passive walking was on average 50% of peak HR (HRpeak ) (161 ± 13 bpm). Test-retest reliability was moderate for V̇O2R (R=0.62) and resting HR (HRR ) (R=0.68), high for V̇O2P (R=0.81), passive HR (HRP ) (R=0.87) and HRpeak (R=0.88), and very high (R=0.95) for V̇O2peak . Only HRP differed significantly between tests (p=0.029). Conclusions: The intensity of passive walking during RATE is low and is insufficient to increase cardiopulmonary fitness in people with SCI. Subjects must actively contribute to the exercise in order to achieve the recommended training intensity. Show more

DOI: 10.3233/THC-2011-0608

Citation: Technology and Health Care, vol. 19, no. 1, pp. 21-27, 2011

Authors: Lerch, Matthias | Olender, Gavin | Angrisani, Nina | Rittershaus, Dina | Meyer-Lindenberg, Andrea | Thorey, Fritz | Windhagen, Henning | Hurschler, Christof

Article Type: Research Article

Abstract: Recent studies have assumed micro-fractures of the femoral head during hip resurfacing arthroplasty as a possible reason for fractures at the implant/neck junction. The purpose of this study was to analyze whether implantation of a cementless femoral hip resurfacing component which requires high seating forces, causes micro-fractures of the femoral head. A cementless hip resurfacing femoral component was installed on 20 human, cadaveric femoral heads with an impaction device that generated 4.5 kilonewton force in one group and by hand in the other. Before and after impaction, the specimens were scanned with a μ-CT-System. The CT datasets were …segmented and registered for detection of small trabecular fractures. The average percentage of shared voxels was 80.29% (standard deviation 3.24%). Change in bone structure after impaction (19.71%) was found on the surfaces of all samples. No formation that was ascribed to fracture was found. No difference between the specimens that were impacted by hand or by impaction device was noted. No fractures of the cancellous femoral head during installation of a cementless femoral THR component occurred. Cementless hip resurfacing might not increase the risk of fracturing the cancellous femoral head during implantation in a cadaveric μ-CT study. Show more

Keywords: Hip resurfacing arthroplasty, cementless, micro-fractures, μ-CT, voxel

DOI: 10.3233/THC-2011-0609

Citation: Technology and Health Care, vol. 19, no. 1, pp. 29-36, 2011

Authors: Hong, Xin | Nugent, Chris

Article Type: Research Article

Abstract: Automated recognition of activities of daily living such as preparing meals and grooming may be considered as one of the most desirable computational functions within a Smart Home for the elderly. In our current work we present a process framework with the capability of realising evidential ontology networks for recognising activities of daily living in a single-person occupied inhabitancy. The performance of this framework has been evaluated using a publicly available data set consisting of 28 days worth of sensor data which was recorded from a single person living in an apartment. Within the paper we show how evidential inference …networks of activities of daily living can be generated from the smart home and subsequently used to represent sensor evidence and activity performance. Based on exposure to the data set considered within the study the model achieved an overall class accuracy of 83.4% and timeslice accuracy of 95.7%. Previously reported attempts to classify this data based on a probabilistic approach achieved rates in the region of 79.4% and 94.5% respectively. Show more

Keywords: Smart homes, ADL recognition, binary sensors, evidential ontology network of activity

DOI: 10.3233/THC-2011-0610

Citation: Technology and Health Care, vol. 19, no. 1, pp. 37-52, 2011

Authors: Niederer, Peter

Article Type: Editorial

DOI: 10.3233/THC-2011-0585D

Citation: Technology and Health Care, vol. 19, no. 1, pp. 53-53, 2011

Authors: Plunkett, Niamh | O'Brien, Fergal J.

Article Type: Research Article

Abstract: A bioreactor can be defined as a device that uses mechanical means to influence biological processes. In tissue engineering bioreactors can be used to aid in the in vitro development of new tissue by providing biochemical and physical regulatory signals to cells and encouraging them to undergo differentiation and/or to produce extracellular matrix prior to in vivo implantation. This chapter discusses the necessity for bioreactors in tissue engineering, the numerous types of bioreactor that exist, the means by which they stimulate cells and how their functionality is governed by the requirements of the specific tissue being engineered and the cell …type undergoing stimulation. Show more

Keywords: Bioreactor, stimulation, mechanobiology, tissue formation

DOI: 10.3233/THC-2011-0605

Citation: Technology and Health Care, vol. 19, no. 1, pp. 55-69, 2011