321 research outputs found

    Stochastic master surgery scheduling

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    The aim of the Master Surgery Scheduling Problem (MSSP) is to schedule the medical specialties to the different operating rooms available, such that surgeries may be performed efficiently. We consider a MSSP where elective and emergency patients can be treated in the same operating rooms. In addition to elective-dedicated operating room slots, flexible operating room slots are introduced to handle the fluctuating demand of emergency patients. To solve the MSSP, we propose a simulation-optimization approach consisting of a two-stage stochastic optimization model and a discrete-event simulation model. For the two-stage stochastic optimization model, uncertain arrivals of emergency patients are represented by discrete scenarios. The discrete-event simulation model is developed to address uncertainty related to the surgery duration and the length of stay at the hospital, and to test the Master Surgery Schedule (MSS) developed by the optimization model in a stochastic operational-level environment. In addition, the simulation model is used to generate scenarios for the optimization model. We present some general advice for surgery scheduling based on testing the optimization model in a numerical study. The simulation-optimization approach is applied to a case study from a hospital department that treats both elective and emergency patients. The optimized MSS outperforms the manually generated MSS, both in terms of emergency waiting time for surgery, and emergency interruptions to the flow of electives.acceptedVersio

    Reliability of maximum oxygen uptake in cardiopulmonary exercise testing with continuous laryngoscopy

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    Aims: A cardiopulmonary exercise test (CPET) is the gold standard to evaluate symptom-limiting exercise intolerance, while continuous laryngoscopy performed during exercise (CLE) is required to diagnose exercise-induced laryngeal obstruction. Combining CPET with CLE would save time and resources; however, the CPET data may be distorted by the extra equipment. We therefore aimed to study whether CPET with CLE influences peak oxygen uptake (V′O2peak) and other gas exchange parameters when compared to a regular CPET. Methods: Forty healthy athletes without exercise-related breathing problems, 15–35 years of age, performed CPET to peak exercise with and without an added CLE set-up, in randomised order 2–4 days apart, applying an identical computerised treadmill protocol. Results: At peak exercise, the mean difference (95% confidence interval) between CPET with and without extra CLE set-up for V′O2peak, respiratory exchange ratio (RER), minute ventilation (V′E) and heart rate (HR) was 0.2 (−0.4 to 0.8) mL·kg−1·min−1, 0.01(−0.007 to 0.027) units, 2.6 (−1.3 to 6.5) L·min−1 and 1.4 (−0.8 to 3.5) beats·min−1, respectively. Agreement (95% limits of agreement) for V′O2peak, RER and V′E was 0.2 (±3.7) mL·kg−1·min−1, 0.01 (±0.10) units and 2.6 (±24.0) L·min−1, respectively. No systematic or proportional bias was found except for the completed distance, which was 49 m (95% CI 16 to 82 m) longer during CPET. Conclusion: Parameters of gas exchange, including V′O2peak and RER, obtained from a maximal CPET performed with the extra CLE set-up can be used interchangeably with data obtained from standard CPET, thus preventing unnecessary additional testing.publishedVersio

    Acupuncture for chronic neck pain: a pilot for a randomised controlled trial

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    Background: Acupuncture is increasingly being used for many conditions including chronic neck pain. However the evidence remains inconclusive, indicating the need for further well-designed research. The aim of this study was to conduct a pilot randomised controlled parallel arm trial, to establish key features required for the design and implementation of a large-scale trial on acupuncture for chronic neck pain. Methods: Patients whose GPs had diagnosed neck pain were recruited from one general practice, and randomised to receive usual GP care only, or acupuncture ( up to 10 treatments over 3 months) as an adjunctive treatment to usual GP care. The primary outcome measure was the Northwick Park Neck Pain Questionnaire (NPQ) at 3 months. The primary analysis was to determine the sample size for the full scale study. Results: Of the 227 patients with neck pain identified from the GP database, 28 (12.3%) consenting patients were eligible to participate in the pilot and 24 (10.5%) were recruited to the trial. Ten patients were randomised to acupuncture, receiving an average of eight treatments from one of four acupuncturists, and 14 were randomised to usual GP care alone. The sample size for the full scale trial was calculated from a clinically meaningful difference of 5% on the NPQ and, from this pilot, an adjusted standard deviation of 15.3%. Assuming 90% power at the 5% significance level, a sample size of 229 would be required in each arm in a large-scale trial when allowing for a loss to follow-up rate of 14%. In order to achieve this sample, one would need to identify patients from databases of GP practices with a total population of 230,000 patients, or approximately 15 GP practices roughly equal in size to the one involved in this study (i.e. 15,694 patients). Conclusion: This pilot study has allowed a number of recommendations to be made to facilitate the design of a large-scale trial, which in turn will help to clarify the existing evidence base on acupuncture for neck pain

    Randomised controlled trial of cervical radiofrequency lesions as a treatment for cervicogenic headache [ISRCTN07444684]

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    BACKGROUND: Cervicogenic headache (CEH) is a unilateral headache localised in the neck or occipital region, projecting to the frontal and temporal regions. Since the pathogenesis of this syndrome appears to have an anatomical basis in the cervical region, several surgical procedures aimed at reducing the nociceptive input on the cervical level, have been tested. We developed a sequence of various cervical radiofrequency neurotomies (facet joint denervations eventually followed by upper dorsal root ganglion neurotomies) that proved successful in a prospective pilot trial with 15 CEH patients. To further evaluate this sequential treatment program we conducted a randomised controlled trial METHODS: 30 patients with cervicogenic headache according to the Sjaastad diagnostic criteria, were randomised. 15 patients received a sequence of radiofrequency treatments (cervical facet joint denervation, followed by cervical dorsal root ganglion lesions when necessary), and the other 15 patients underwent local injections with steroid and anaesthetic at the greater occipital nerve, followed by transcutaneous electrical nerve stimulation (TENS) when necessary. Visual analogue scores for pain, global perceived effects scores, quality of life scores were assessed at 8, 16, 24 and 48 weeks. Patients also kept a headache diary. RESULTS: There were no statistically significant differences between the two treatment groups at any time point in the trial. CONCLUSION: We did not find evidence that radiofrequency treatment of cervical facet joints and upper dorsal root ganglions is a better treatment than the infiltration of the greater occipital nerve, followed by TENS for patients fulfilling the clinical criteria of cervicogenic headache

    Feasibility of a physical activity intervention for children and adolescents with anxiety and depression

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    Background Physical activity is identified as a key modifiable factor towards good short- and long-term mental health and has shown positive effects on anxiety and depression in children and adolescents. However, physical activity-based interventions are not a part of standard mental health care and evidence on the effect of such interventions is still lacking. A transdiagnostic, physical activity-based intervention was developed as a supplement to routine clinical care for youth in specialized child and adolescent mental health services. Methods /design. The feasibility of the physical activity intervention (Confident, Active, and Happy Youth) was evaluated in an open-label study by assessing the recruitment process, acceptability, intervention suitability, contentment, and preliminary intervention effects in the form of youth and parent-rated anxiety and depressive symptoms. Physical activity levels were objectively measured using Actigraph™ physical activity sensors, and progression to a definitive study was evaluated in accordance with a priori criteria. Results In total 21 of 25 eligible youth consented to participate, two dropped out of the intervention and 19 completed (76% of eligible participants). The retention rate among consenting participants was 89% and mean attendance to sessions was 83%. The suitability of the intervention was rated as good by the youth and their parents, and intervention contentment was rated high. Changes in youth and parent-rated symptom measures following the intervention were negligible, except for parent-rated anxiety symptoms assessed at 10-month follow-up. Accelerometer data indicated lower levels of moderate to vigorous activity during sessions than intended. No adverse effects were noted. Conclusion This feasibility study met the pre-determined progression criteria to a definitive study. Thus, a larger trial with longer follow-up should be conducted to explore the effect of the intervention. Trial registration ClnicalTrials.gov, NCT05049759. Retrospectively registered, 20.09.2021

    Ultrasonic doppler flowmeter-guided occipital nerve block

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    BACKGROUND: Greater occipital nerve block is used in the treatment of headaches and neuralgia in the occipital area. We evaluated the efficacy of ultrasonic doppler flowmeter-guided occipital nerve block in patients experiencing headache in the occipital region in a randomized, prospective, placebo-controlled study. METHODS: Twenty-six patients, aged 18 to 70, with headache in the occipital region, were included in the study. Patients received a greater occipital nerve block performed either under ultrasonic doppler flowmeter guidance using 1% lidocaine or the traditional method. Sensory examination findings in the occipital region were evaluated. RESULTS: The complete block rate of greater occipital nerve blockade in the doppler group was significantly higher than in the control group respectively (76.9% vs. 30.8%, P < 0.05). Only one patient in the control group had a complication (minimal bleeding). CONCLUSIONS: Ultrasonic doppler flowmeter-guided occipital nerve block may be a useful method for patients suffering headache in the occipital region.ope

    The Physical Activity and Fitness in Childhood Cancer Survivors (PACCS) Study: Protocol for an International Mixed Methods Study

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    BACKGROUND Survivors of childhood cancer represent a growing population with a long life expectancy but high risks of treatment-induced morbidity and premature mortality. Regular physical activity (PA) may improve their long-term health; however, high-quality empirical knowledge is sparse. OBJECTIVE The Physical Activity and Fitness in Childhood Cancer Survivors (PACCS) study comprises 4 work packages (WPs) aiming for the objective determination of PA and self-reported health behavior, fatigue, and quality of life (WP 1); physical fitness determination (WP 2); the evaluation of barriers to and facilitators of PA (WP 1 and 3); and the feasibility testing of an intervention to increase PA and physical fitness (WP 4). METHODS The PACCS study will use a mixed methods design, combining patient-reported outcome measures and objective clinical and physiological assessments with qualitative data gathering methods. A total of 500 survivors of childhood cancer aged 9 to 18 years with ≥1 year after treatment completion will be recruited in follow-up care clinics in Norway, Denmark, Finland, Germany, and Switzerland. All participants will participate in WP 1, of which approximately 150, 40, and 30 will be recruited to WP 2, WP3, and WP 4, respectively. The reference material for WP 1 is available from existing studies, whereas WP 2 will recruit healthy controls. PA levels will be measured using ActiGraph accelerometers and self-reports. Validated questionnaires will be used to assess health behaviors, fatigue, and quality of life. Physical fitness will be measured by a cardiopulmonary exercise test, isometric muscle strength tests, and muscle power and endurance tests. Limiting factors will be identified via neurological, pulmonary, and cardiac evaluations and the assessment of body composition and muscle size. Semistructured, qualitative interviews, analyzed using systematic text condensation, will identify the perceived barriers to and facilitators of PA for survivors of childhood cancer. In WP 4, we will evaluate the feasibility of a 6-month personalized PA intervention with the involvement of local structures. RESULTS Ethical approvals have been secured at all participating sites (Norwegian Regional Committee for Medical Research Ethics [2016/953 and 2018/739]; the Oslo University Hospital Data Protection Officer; equivalent institutions in Finland, Denmark [file H-19032270], Germany, and Switzerland [Ethics Committee of Northwestern and Central Switzerland, project ID: 2019-00410]). Data collection for WP 1 to 3 is complete. This will be completed by July 2022 for WP 4. Several publications are already in preparation, and 2 have been published. CONCLUSIONS The PACCS study will generate high-quality knowledge that will contribute to the development of an evidence-based PA intervention for young survivors of childhood cancer to improve their long-term care and health. We will identify physiological, psychological, and social barriers to PA that can be targeted in interventions with immediate benefits for young survivors of childhood cancer in need of rehabilitation. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) DERR1-10.2196/35838

    Clinical Efficacy of Radiofrequency Cervical Zygapophyseal Neurotomy in Patients with Chronic Cervicogenic Headache

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    The purpose of the present study was to assess the clinical efficacy of radiofrequency (RF) cervical zygapophyseal joint neurotomy in patients with cervicogenic headache. A total of thirty consecutive patients suffering from chronic cervicogenic headaches for longer than 6 months and showing a pain relief by greater than 50% from diagnostic/prognostic blocks were included in the study. These patients were treated with RF neurotomy of the cervical zygapophyseal joints and were subsequently assessed at 1 week, 1 month, 6 months, and at 12 months following the treatment. The results of this study showed that RF neurotomy of the cervical zygapophyseal joints significantly reduced the headache severity in 22 patients (73.3%) at 12 months after the treatment. In conclusion, RF cervical zygapophyseal joint neurotomy has shown to provide substantial pain relief in patients with chronic cervicogenic headache when carefully selected
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