Anders Nielsen

MD,MPA,MPH

Research interests

  • Interests
    Discrete Event Simulation, Health Care Administration, Health Care Informatics, Oxygen, Health Care Economics

Publications

  • 0.83
    Impact points
    Changes in HIV needs identified by the National AIDS Hotline of Trinidad and Tobago.

    Sandra D Reid, Anders L Nielsen, Rhoda Reddock

    Revista panamericana de salud pública = Pan American journal of public health. 02/2010; 27(2):93-102.

    To examine utilization of the National AIDS Hotline of Trinidad and Tobago (AIDSLINE), evaluate its validity as a reliable data source for monitoring national HIV-related needs, and identify changes in caller requests between two different time periods. A total of 7 046 anonymous hotline calls in 19... [more] To examine utilization of the National AIDS Hotline of Trinidad and Tobago (AIDSLINE), evaluate its validity as a reliable data source for monitoring national HIV-related needs, and identify changes in caller requests between two different time periods. A total of 7 046 anonymous hotline calls in 1998-2002 (T1) and 2 338 calls in 2007 (T2) were analyzed for associations between caller characteristics and call content. A subsample of the data was also analyzed qualitatively. T1 findings were compared with HIV-related data collected by national policy-makers during that period, to evaluate the hotline's validity as a data source, and findings from T2, to reveal changes in call content over time. In T1, the hotline was well utilized for information and counseling by both the general population and those living with HIV/AIDS. Call content from T2 indicated an increase versus T1 in 1) general awareness of HIV and other sexually transmitted diseases; 2) HIV testing; and 3) knowledge of HIV symptoms and transmission. HIV-related mental health needs, and the relationship between HIV and both child sexual abuse (CSA) and intimate partner violence (IPV), were identified as emerging issues. AIDSLINE is a well-utilized tool for providing information and counseling on national HIV-related issues, and a valid, cost-effective, easily accessed information source for planners and policy-makers involved in HIV management. Over the two study periods, there was an increase in HIV awareness and testing and in requests related to mental health, CSA, and IPV, but no change in sexual behaviors.
  • Discrete event simulation as a tool in optimization of a professional complex adaptive system.

    Anders Lassen Nielsen, Helmer Hilwig, Niranjan Kissoon, Surujpal Teelucksingh

    Studies in health technology and informatics. 02/2008; 136:247-52.

    Similar urgent needs for improvement of health care systems exist in the developed and developing world. The culture and the organization of an emergency department in developing countries can best be described as a professional complex adaptive system, where each agent (employee) are ignorant of th... [more] Similar urgent needs for improvement of health care systems exist in the developed and developing world. The culture and the organization of an emergency department in developing countries can best be described as a professional complex adaptive system, where each agent (employee) are ignorant of the behavior of the system as a whole; no one understands the entire system. Each agent's action is based on the state of the system at the moment (i.e. lack of medicine, unavailable laboratory investigation, lack of beds and lack of staff in certain functions). An important question is how one can improve the emergency service within the given constraints. The use of simulation signals is one new approach in studying issues amenable to improvement. Discrete event simulation was used to simulate part of the patient flow in an emergency department. A simple model was built using a prototyping approach. The simulation showed that a minor rotation among the nurses could reduce the mean number of visitors that had to be refereed to alternative flows within the hospital from 87 to 37 on a daily basis with a mean utilization of the staff between 95.8% (the nurses) and 87.4% (the doctors). We conclude that even faced with resource constraints and lack of accessible data discrete event simulation is a tool that can be used successfully to study the consequences of changes in very complex and self organizing professional complex adaptive systems.
  • 1.35
    Impact points
    Retrospective incremental cost analysis of a hospital-based COPD Disease Management Programme in Sweden.

    Alf Tunsäter, Mikael Moutakis, Sixten Borg, Ulf Persson, Leif Strömberg, Anders Lassen Nielsen

    Health policy (Amsterdam, Netherlands). 06/2007; 81(2-3):309-19.

    This paper reports on a retrospective analysis of hospital-based healthcare costs associated with the management of chronic obstructive pulmonary disease (COPD). During the second half of 2001, Simrishamn Hospital, Sweden, implemented a structured Disease Management Programme (DMP) for COPD and a to... [more] This paper reports on a retrospective analysis of hospital-based healthcare costs associated with the management of chronic obstructive pulmonary disease (COPD). During the second half of 2001, Simrishamn Hospital, Sweden, implemented a structured Disease Management Programme (DMP) for COPD and a total of 784 patients with COPD, enrolled in the DMP, were included in the analysis. The goal was to reduce the number of clinical events, such as severe exacerbations by early intervention, aggressive drug treatment, specialists easy available for advice, improved support for smoking cessation, increased number of scheduled follow-ups and closer tracking of high-risk COPD patients. The hospital administrative system provided data on resource consumption, such as outpatient care, inpatient care and drugs and unit cost, used in the economic analysis. The total cost of COPD drugs doubled (from euro 14,133 to euro 30,855 per year) as did the total number of outpatient visits (from 580 to 996 visits per year). The number of hospitalizations for acute COPD exacerbations and COPD with acute lower respiratory infection decreased from 67 to 25 per year. Total COPD-related healthcare costs decreased. The results presented here support the hypothesis that a COPD DMP can offer substantial overall direct cost savings.
  • 1.89
    Impact points
    Assessment of pH and oxygen status during hemodialysis using the arterial blood line in patients with an arteriovenous fistula.

    A L Nielsen, P Thunedborg, H Brinkenfeldt, J Hegbrant, H A Jensen, J H Wandrup

    Blood purification. 02/1999; 17(4):206-12.

    BACKGROUND: In patients with arteriovenous fistulas, assessment of pH and oxygen status during hemodialysis (HD) using the extracorporeal dialysis arterial blood line is widely used both in daily routine and in most studies investigating hypoxia during HD. We designed this study to evaluate whether ... [more] BACKGROUND: In patients with arteriovenous fistulas, assessment of pH and oxygen status during hemodialysis (HD) using the extracorporeal dialysis arterial blood line is widely used both in daily routine and in most studies investigating hypoxia during HD. We designed this study to evaluate whether results of blood gas samples drawn from the extracorporeal arterial line were clinically acceptable in assessing oxygen status. METHODS: We compared samples drawn from the extracorporeal arterial line with conventionally arterial punctures during 18 routine HD sessions. The samples were drawn simultaneously and analyzed immediately for blood gases, pH and hemoximetry values. RESULTS: No significant difference was found between the values from the radial artery and the extracorporeal arterial blood line except for FMetHb. CONCLUSION: Thus, obtaining samples from the extracorporeal dialysis arterial blood line to evaluate the parameters of the oxygen status (pH, pO(2), pCO(2), ctHb, sO(2), FCOHb and ctO(2)) during routine HD is a clinically convenient and accurate sampling approach.
  • 1.38
    Impact points
    Oxygen and 2,3 biphosphoglycerate (2,3-BPG) during haemodialysis.

    A L Nielsen, E M Andersen, L G Jørgensen, H A Jensen

    Scandinavian journal of clinical and laboratory investigation. 11/1998; 58(6):459-67.

    Eleven patients with chronic renal failure who were being treated with haemodialysis three times a week were monitored for a total of 34 haemodialysis sessions. Erythrocyte 2,3-biphosphoglycerate (2,3-BPG) concentration was analysed immediately before initiation of bicarbonate haemodialysis and 1 h ... [more] Eleven patients with chronic renal failure who were being treated with haemodialysis three times a week were monitored for a total of 34 haemodialysis sessions. Erythrocyte 2,3-biphosphoglycerate (2,3-BPG) concentration was analysed immediately before initiation of bicarbonate haemodialysis and 1 h afterwards. The 2,3-BPG concentration was expressed relative to the haemoglobin tetramer (Hb4) concentration as the 2,3-BPG/Hb4 ratio and compared with blood gas analyses and biochemical variables important for characterizing uraemia. During the first hour of haemodialysis the 2,3-BPG/Hb4 ratio decreased (p < 0.002), but the magnitude of the decrease did not significantly correlate with the 2,3-BPG/Hb4 ratio measured before haemodialysis (p=0.104). The decrease is most likely to be caused by the haemodialysis procedure itself. Mechanical stress on the erythrocytes is believed to cause the 2,3-BPG to escape; it is then removed by haemodialysis. Physiologically, an increase in 2,3-BPG would be expected to counteract the hypoxia which is frequently observed during haemodialysis. However, the present results show the opposite, a decrease in 2,3-BPG. No significant correlation was shown between the haemoglobin concentration and the 2,3-BPG/Hb4 ratio before dialysis (p=0.414). The pH showed a significant positive correlation with the 2,3-BPG/Hb4 ratio before dialysis, whereas the arterial pO2 and the 2,3-BPG/Hb4 ratio before dialysis were insignificantly negatively correlated. The concentrations of calcium, phosphate, creatinine, urea and albumin did not correlate significantly with the change in 2,3-BPG/Hb4-ratio after 1 h. The 2,3-BPG/Hb4 ratio (p=0.03) sampled just before dialysis correlated significantly and positively with the total weekly dosage of erythropoietin given to the patients.
  • 1.89
    Impact points
    Beneficial effect of cold dialysate for the prevention of hemodialysis-induced hypoxia.

    J Hegbrant, J Sternby, A Larsson, L Mårtensson, A Lassen Nielsen, H Thysell

    Blood purification. 02/1997; 15(1):15-24.

    Hypoxia occurs frequently during routine hemodialysis (HD). In this study the effect of dialysate temperature on arterial blood gas parameters was investigated. Ten stable HD patients (2 smokers) were dialyzed for 240 min with each of three different dialysate temperatures: 36.5 degrees C (normal te... [more] Hypoxia occurs frequently during routine hemodialysis (HD). In this study the effect of dialysate temperature on arterial blood gas parameters was investigated. Ten stable HD patients (2 smokers) were dialyzed for 240 min with each of three different dialysate temperatures: 36.5 degrees C (normal temperature HD; NHD), 38.5 degrees C (warm HD; WHD) and 34.5 degrees C (cold HD; CHD). A cuprophane plate dialyzer was used. The ultrafiltration volume was identical in each patient. Arterial blood gas samples were frequently (approximately 10 times/treatment) taken during the dialysis and immediately analyzed. The dialysate temperature significantly affected PaO2 (p < 0.001) but not PaCO2. We also compared the effect of NHD with that of WHD and CHD, respectively, as regards PaO2. NHD and WHD differed significantly p < 0.01), whereas NHD and CHD were not significantly different. However, the relative PaO2 value (% of the baseline value) at the end of CHD (105 +/- 5%) was significantly higher than after both NHD (96 +/- 4%, p < 0.01) and WHD (91 +/- 3%, p < 0.01). In the case of NHD and WHD the fraction of time during which the patients had a PaO2 value below 80 mm Hg was 62 and 64%, respectively. The corresponding figure for CHD was 44%. Arterial oxygen saturation (SaO2) increased during CHD from 95.2 +/- 0.6 to 96.7 +/- 0.6% (p < 0.05), while SaO2 was unchanged during NHD and WHD. The positive effect of CHD was evident in 7 patients. In 1 patient PaO2 was not affected by the dialysate temperature, while in the remaining 2 patients (smokers) a decrease in PaO2 was induced by WHD as well as CHD. A separate statistical analysis with the 2 smokers excluded was performed, which showed that the dialysate temperature significantly affected PaO2 (p < 0.001). A comparison between NHD and CHD showed a significant difference (p < 0.001), whereas NHD and WHD did not differ significantly. When the 2 smokers were excluded from the analysis the fraction of time with a PaO2 value below 80 mm Hg was 60% during NHD and 56% during WHD, but it was reduced to 31% during CHD. In conclusion, despite the existence of interindividual variations most patients seemed to benefit from cold dialysate for the prevention of dialysis-induced hypoxia.
  • 0.88
    Impact points
    Continuous registration of blood oxygen tension during hemodialysis.

    N Løkkegaard, A L Nielsen, P B Brekke

    Scandinavian journal of urology and nephrology. 09/1995; 29(3):249-58.

    Continuous monitoring of blood oxygen tension was carried out during 45 hemodialyses sessions. The oxygen tension curves displayed different appearances. Some curves presented with a periodicity like sinus curves (type 1), while others (type 2) fluctuated with other appearances, or displayed straigh... [more] Continuous monitoring of blood oxygen tension was carried out during 45 hemodialyses sessions. The oxygen tension curves displayed different appearances. Some curves presented with a periodicity like sinus curves (type 1), while others (type 2) fluctuated with other appearances, or displayed straight lines. Blood pressure variations during dialysis were significantly greater during dialyses displaying type 1 curves than during those displaying type 2 curves (p values < 0.02). Due to a greater descend of S-urea during dialyses with type 1 curves than during dialyses with type 2 curves (p < 0.05) it is hypothesized, that the intensity of the dialysis treatment could be of some importance to the observed fluctuations in oxygen tension.
  • 0.88
    Impact points
    Carbon monoxide in chronic uraemia related to erythropoietin treatment and smoking habits.

    P Thunedborg, A L Nielsen, H Brinkenfeldt, J Brahm, H A Jensen

    Scandinavian journal of urology and nephrology. 04/1995; 29(1):21-5.

    In 69 patients on chronic haemodialysis, blood sampled randomly during dialysis was analyzed for carboxyhaemoglobin (COHb). The median value was 1.40% (range 0.9-2.3) in non-smoking patients and (1.4-7.5) in smokers. In non-smokers treated with erythropoietin (EPO) correlation was found between COHb... [more] In 69 patients on chronic haemodialysis, blood sampled randomly during dialysis was analyzed for carboxyhaemoglobin (COHb). The median value was 1.40% (range 0.9-2.3) in non-smoking patients and (1.4-7.5) in smokers. In non-smokers treated with erythropoietin (EPO) correlation was found between COHb and the weekly EPO dose (r = 0.57, p = 0.007). In smoking patients not given EPO, the COHb correlated well with the number of cigarettes smoked (r = 0.84, p = 0.003). The COHb values did not correlate to the haemoglobin values. It is concluded that COHb levels in uraemic non-smokers are elevated because of increased endogenous CO production from the enhanced erythrocyte turnover. As even low COHb levels may negatively influence the oxygen status of the uraemic patient, the addition of exogenous CO from cigarette smoking should be avoided.
  • Oxygen status during haemodialysis. The Cord-Group.

    A L Nielsen, H A Jensen, J Hegbrant, H Brinkenfeldt, P Thunedborg

    Acta anaesthesiologica Scandinavica. Supplementum. 02/1995; 107:195-200.

    Hypoxia during haemodialysis, mainly acetate, has been reported several times. In our study we have monitored oxygen status during 258 bicarbonate haemodialyses. A significant drop below 80 mmHg in mean oxygen tension occurred. Mean oxygen saturation reflected this drop but did not reach levels belo... [more] Hypoxia during haemodialysis, mainly acetate, has been reported several times. In our study we have monitored oxygen status during 258 bicarbonate haemodialyses. A significant drop below 80 mmHg in mean oxygen tension occurred. Mean oxygen saturation reflected this drop but did not reach levels below 90%. The mean oxygen concentration was on the whole critical low, though slightly increasing during each haemodialysis session due to ultrafiltration. It is concluded that both hypoxia and hypoxaemia do occur during bicarbonate haemodialysis. To a group of patients generally having limited cardiac reserves, a poor oxygen status is a potentially serious complication to haemodialysis. Monitoring oxygen status is thus advisable.
  • 1.42
    Impact points
    Peritoneal equilibration test performed in predialysis patients.

    L J Petersen, A L Nielsen

    The International journal of artificial organs. 02/1995; 18(1):3-5.

    The aim of the study was to perform peritoneal equilibration test (PET) in predialysis patients, and compared to PET results in patients on chronic peritoneal dialysis (PD). Two groups of patients were enrolled in the study. Group 1: eleven uremic patients who had never been subjected to PD, and gro... [more] The aim of the study was to perform peritoneal equilibration test (PET) in predialysis patients, and compared to PET results in patients on chronic peritoneal dialysis (PD). Two groups of patients were enrolled in the study. Group 1: eleven uremic patients who had never been subjected to PD, and group 2: fourteen patients on maintenance PD. The PET was performed as the four hour standard PET, using a 2 liter bag (Dianeal 2.5% glucose) as test fluid. The transport of creatinine through the peritoneum did not differ significantly between the groups corresponding to the dialysate to plasma (D/P) ratios, neither did the glucose ratios differ significantly. After two hours dwell time a significant difference was found in D/P ratio of urea (p = 0.001), in group 1 the median D/P of urea was 0.90 (0.80-1.14) and 0.75 (0.52-0.84) in group 2. No significant difference was found at dwell time zero or four hours. The current study shows that the distribution of PET results is identical in a group of predialysis patients, as compared to a group of chronic PD patients, except for D/P of urea at two hours dwell time.
  • 13.26
    Impact points
    Delayed decrease in plasma levels of atrial natriuretic peptide during cold hemodialysis.

    J Hegbrant, H Thysell, L Mårtensson, A L Nielsen, B F Lindberg

    Nephron. 02/1994; 68(4):427-32.

    The high plasma levels of the vasodilating hormone atrial natriuretic peptide (alpha-ANP), observed in patients with chronic renal failure, decrease substantially during hemodialysis (HD), probably owing to volume reduction. Cardiovascular stability is better maintained by the use of cold dialysate ... [more] The high plasma levels of the vasodilating hormone atrial natriuretic peptide (alpha-ANP), observed in patients with chronic renal failure, decrease substantially during hemodialysis (HD), probably owing to volume reduction. Cardiovascular stability is better maintained by the use of cold dialysate although underlying mechanisms are unknown. In order to investigate the effects of different dialysate temperatures on hemodynamic stability and plasma levels of immunoreactive ANP (p-irANP), 10 stable HD patients were dialyzed with bicarbonate dialysis fluid for 240 min with each of 3 different dialysate temperatures: 36.5 degrees C (normal HD; NHD), 38.5 degrees C (warm HD; WHD) and 34.5 degrees C (cold HD; CHD). A Cuprophan plate dialyzer was used. The ultrafiltration volume and ultrafiltration rate were identical in each patient during the treatments. p-irANP was determined by radioimmunoassay, using 2 antisera which different cross-reactivity to ANP-related peptides. During NHD a nonsignificant decrease in mean arterial blood pressure from 111 +/- 5 to 103 +/- 8 mm Hg was observed. A significant (p < 0.05) decrease in mean arterial blood pressure from 109 +/- 4 to 96 +/- 6 mm Hg occurred during WHD, while during CHD it remained stable (111 +/- 4 before, 112 +/- 5 mm Hg after). Irrespective of the dialysate temperature or the antiserum used, p-irANP decreased significantly (p < 0.05) during the treatment. The reduction in p-irANP was delayed during CHD, the decrease being significantly (p < 0.05) less pronounced after 120 min. At the end of the treatment no significant difference was observed between the regimes.(ABSTRACT TRUNCATED AT 250 WORDS)
  • [Legionnaires' disease--a multifaceted syndrome]

    T L Katzenstein, G Dahl, A Greulich, A L Nielsen

    Ugeskrift for laeger. 10/1992; 154(40):2762-3.

    Multiorgan involvement is often seen in Legionella infections. We report two cases, with classical pneumonia complicated by facial paresis and severe kidney affection demanding haemodialysis. One patient had Legionella infection concomitantly with pneumococcal pneumonia. As the diagnosis often is no... [more] Multiorgan involvement is often seen in Legionella infections. We report two cases, with classical pneumonia complicated by facial paresis and severe kidney affection demanding haemodialysis. One patient had Legionella infection concomitantly with pneumococcal pneumonia. As the diagnosis often is not verified till weeks after onset of illness, it is concluded that the treatment should be started and maintained on clinical suspicion. Isolation of another respiratory pathogen does not exclude the possibility of Legionella infection.
  • 1.59
    Impact points
    Epidemiology of injuries in Danish championship tennis.

    S Winge, U Jørgensen, A Lassen Nielsen

    International journal of sports medicine. 11/1989; 10(5):368-71.

    During the outdoor tennis season of 1984 a prospective injury registration was done in 104 randomly chosen elite tennis players, of whom 86% could be followed. We found 46 injuries: an incidence of 2.3 injuries/player/1000 tennis hours. Men were more frequently injured than women. The prevalence was... [more] During the outdoor tennis season of 1984 a prospective injury registration was done in 104 randomly chosen elite tennis players, of whom 86% could be followed. We found 46 injuries: an incidence of 2.3 injuries/player/1000 tennis hours. Men were more frequently injured than women. The prevalence was 0.3 injury/player. Upper extremity injuries were most frequent - 45.7% (21/46). Shoulder injuries were the single most frequent injury - 17% (8/46). The pathophysiology was overuse in 67% (28/42), strains in 14% (6/42), sprains in 17% (7/42), fractures in 2% (1/42), and blisters in 5% (2/42). Players using conventional rackets had more injuries to the upper extremity compared with players using mid/oversized rackets, though the difference was nonsignificant. The importance of impact forces from the tennis stroke in the mechanism of upper extremity injuries is discussed.
  • 1.39
    Impact points
    Dialysis fluid temperature and vasoactive substances during routine hemodialysis.

    J Hegbrant, L Mãrtensson, R Ekman, A L Nielsen, H Thysell

    ASAIO journal (American Society for Artificial Internal Organs : 1992). 40(3):M678-82.

    Blood pressure stability is better during cold hemodialysis (HD). This has mainly been attributed to a more pronounced sympathetic activation during cold than during warm HD. The authors studied the effect of dialysate temperature on vasoactive peptides, noradrenaline (NA), and renin (PRA). Ten hemo... [more] Blood pressure stability is better during cold hemodialysis (HD). This has mainly been attributed to a more pronounced sympathetic activation during cold than during warm HD. The authors studied the effect of dialysate temperature on vasoactive peptides, noradrenaline (NA), and renin (PRA). Ten hemodynamically stable patients were dialyzed for 240 min with each of two dialysate temperatures: 38.5 degrees C (warm HD = WHD) and 34.5 degrees C (cold HD = CHD). A decrease (P < 0.05) in blood pressure occurred during WHD; however, during CHD, blood pressure was stable. There were no differences in vasoconstrictors between the two regimens. There was a decrease in NA (P < 0.05), a tendency of PRA to increase (NS owing to a large statistical spread), while arginine vasopressin was unchanged. During CHD, there was a small increase in neuropeptide Y (NPY); however, during WHD, NPY only tended to increase. However, the relative NPY levels (percent of baseline levels) after WHD and CHD did not differ. The vasodilator response was similar during both treatments. Calcitonin gene related peptide was unaltered. Motilin tended to decrease initially, but then increased (P < 0.05) to baseline levels. An increase occurred in beta-endorphin (P < 0.05) and substance P(P < 0.01). There was an initial rise (P < 0.05) in vasoactive intestinal peptide (VIP), followed by a tendency to decrease during the remainder of treatment. The authors concluded that blood pressure stability was better during CHD. However, this was not reflected by differences in plasma levels of the vasoactive peptides, nor did they find any difference in the sympathetic drive between the two regimens.

Following (1)

17
Publications