Biomedical subjects

A Voss

Publications and source records attributed to A Voss.

At least 19 recordsLinked to original sources

PubMed2006

Detection of a new SHV-type extended-spectrum beta-lactamase, SHV-31, in a Klebsiella pneumoniae strain causing a large nosocomial outbreak in The Netherlands.

A Klebsiella pneumoniae strain resistant to third-generation cephalosporins was isolated in the eastern Netherlands. The strain was found to carry a novel extended-spectrum beta-lactamase, namely, SHV-31. The combination of the two mutations by which SHV-31 differs from SHV-1, namely, L35Q and E240K, had previously only been described in association with one or more additional mutations.

Anti-Bacterial Agents↗

PubMed2006

How many infection control staff do we need in hospitals?

During a one-day workshop experienced infection control practitioners (ICPs) and medical microbiologists debated how much time was needed for the delivery of infection control activities in a model hospital. They agreed a standard of one full-time equivalent (FTE) ICP per 178 hospital beds and one FTE medical microbiologist per 806 hospital beds. This is 40% and 24% more than the usual standard, respectively. Now that official numbers of hospital beds have become an inadequate parameter for work delivered by hospitals, a new standard is proposed, with the number of admissions as the denominator. This is one FTE ICP per 5000 admissions and one medical microbiologist or epidemiologist per 25000 admissions.

Humans↗

PubMed2006

Quality control for handling of accidental blood exposures.

A regional counselling service was established to handle all accidental blood exposures using a standardized protocol. Levels of risk were assessed using an algorithm. Accidents that posed a risk for the transmission of hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency virus (HIV) were classified as 'high risk', whereas accidents that posed a risk for HBV alone were classified as 'low risk'. Medical interventions were implemented according to the level of risk. During a one-year period, all accidents were registered and analysed for adherence to the standard protocol. In 2003, the centre handled 454 incidents. Of these, 36 (7.9%) incidents were assessed as no risk, 329 (72.5%) were assessed as low risk, and 67 (14.8%) were assessed as high risk. Due to incomplete registration, 22 (4.8%) incidents could not be analysed further. In total, 36% of the incidents with risk for HBV transmission and 40% of the incidents with risk for HCV and HIV transmission were not handled according to the proposed protocol. Breaches consisted of over-reaction (25/396) as well as insufficient response (123/396). Potentially inadequate treatment occurred for HIV postexposure prophylaxis in 12 of 63 incidents. Incomplete follow-up for HCV occurred in 11 of 63 incidents, and lack of HBV immunoglobulin administration occurred in five of 396 incidents, including three high-risk incidents. In 21 of 396 low-risk exposures, the breaches in protocol resulted from late reporting. It remains difficult to achieve an acceptable level of standardized care when using standard operational procedures. Documentation and evaluation of flaws are essential to improve the system.

Accidents↗

PubMed2006

[Scabies outbreak in a hospital and in 8 health-care institutions caused by an elderly patient with scabies crustosa].

An outbreak of scabies in a teaching hospital, two nursing homes and six health-care institutions for the elderly, occurred in the Nijmegen area in the Netherlands, between September 2004 and April 2005. In November 2004 the diagnosis of scabies crustosa (scabies norvegica) was made in the index patient - a 78-year-old woman. An atypical presentation, without much itching, as is not infrequently seen in elderly patients, resulted in there being a considerable delay before the diagnosis was made. This resulted in a total of 51 people, both in and outside the hospital, becoming infected. Based on article 7 of the Dutch Infectious Diseases Act, the Municipal Health Service (GGD) advised institutions on the policy and carried out both source and contact tracing. According to this Act notification and cooperation between hospital, care institutions and the GGD are of importance for the effective handling of epidemics. Systemic treatment with ivermectin is the main alternative to local treatment in outbreaks in institutions.

Aged↗

PubMed2006

Random effect modelling of patient-related risk factors in orthopaedic procedures: results from the Dutch nosocomial infection surveillance network 'PREZIES'.

In the Dutch surveillance for surgical site infections (SSIs), data from 70277 orthopaedic procedures with 1895 SSIs were collected between 1996 and 2003. The aims of this study were: (1) to analyse the trends in SSIs associated with Gram-positive and Gram-negative bacteria; (2) to estimate patient-related risk factors for deep and superficial SSIs after all orthopaedic procedures, with special attention to primary total hip arthroplasty (THA); and (3) to analyse inherent differences in infection risk between hospitals. A random effect model was used to estimate the odds ratios of patient-related risk factors for developing an SSI, and to describe the distribution of the most widespread bacterial species responsible for SSIs among hospitals. Gram-positive organisms, mainly staphylococci, were the main cause of both deep (84.0%) and superficial SSIs (69.1%) after orthopaedic procedures. The percentage of SSIs after THA caused by coagulase-negative staphylococci decreased over the surveillance period, while the contribution of Staphylococcus aureus increased. Temporary elevations in the incidence of the most widespread pathogen species were observed within hospitals. Patient-related factors such as the National Nosocomial Infections Surveillance System risk index or age had little effect on the predictive power of the random effect models. This study underlines the usefulness of a random effect model, which adjusts risk estimates for random variation between hospitals, in a multicentre study on risk factors for SSIs.

Adolescent↗

PubMed2006

Differences between hospital- and community-acquired blood exposure incidents revealed by a regional expert counseling center.

OBJECTIVE: One year (2003) regional analysis of all blood exposure incidents from hospitals as well as from the community. DESIGN: Establishment of an easily accessible regional expert counseling center, operating 24 h a day, for all accidental blood exposures. Tasks of the center were to register incoming calls, to inform and counsel the victim, to assess the risk of the incident, and to provide a plan of further actions, including prophylactic measures. SETTING: A Dutch region (Northeast Brabant) with 500,000 inhabitants and two major hospitals (1,786 beds). RESULTS: A total of 454 incidents (1.2 per day) were recorded. Only half of the incidents occurred in the hospital setting (n = 234), whereas the others (n = 220) took place in the community setting. Nearly all (95%, n = 432) incidents occurred during work, and most of them (84%, n = 385) were related to health care activities. In the hospital setting injuries occurred with physicians (13%), nursing staff (45%), operating room (OR) staff (13%), ancillary (18%), others (10%). In the community setting, incidents took place among healthcare workers (48%), detention and police officers (10%), civilians (10%), general practitioners/dentists and their staff (8%), cleaning staff (4%) and work-related incidents not falling into any of the above categories (7%). More low risk incidents took place outside the hospital (87% vs. 68% in hospital), while high-risk incidents predominantly occurred within the hospital setting (23% vs. 6%). The hepatitis-B immunization rate was significantly lower in victims from the community than in those working in hospitals (38% vs. 96%). Reports from incidents in the community setting were delayed. CONCLUSIONS: Incidents that expose individuals to blood-borne pathogens occur equally frequent in the hospital and non-hospital (community) setting. Therefore, a regional expert counseling center, accessible around-the-clock, for all types of blood-exposure incidents is needed. Blood-exposure prevention programs should aim at a reduction of high-risk incidents within hospitals, and at increasing the awareness for vaccination and early reporting within the community setting.

Accidents, Occupational↗

PubMed2006

Hidden Markov models based on symbolic dynamics for statistical modeling of cardiovascular control in hypertensive pregnancy disorders.

Discrete hidden Markov models (HMMs) were applied to classify pregnancy disorders. The observation sequence was generated by transforming RR and systolic blood pressure time series using symbolic dynamics. Time series were recorded from 15 women with pregnancy-induced hypertension, 34 with preeclampsia and 41 controls beyond 30th gestational week. HMMs with five to ten hidden states were found to be sufficient to characterize different blood pressure variability, whereas significant classification in RR-based HMMs was found using fifteen hidden states. Pregnancy disorders preeclampsia and pregnancy induced hypertension revealed different patho-physiological autonomous regulation supposing different etiology of both disorders.

Algorithms↗

PubMed2006

Linear and nonlinear methods for analyses of cardiovascular variability in bipolar disorders.

OBJECTIVES: Heart rate variability (HRV), blood pressure variability (BPV), and the assessment of baroreflex sensitivity are widely accepted methods for analyzing and characterizing cardiovascular regulation and for an enhanced risk evaluation in different diseases. As a result of the complexity of the investigated regulatory systems, univariate analyses do not often provide a convenient description of pathological changes in the cardiovascular regulation. Therefore, the application of a multivariate approach is preferable. METHODS: We present principal methods of time-domain, frequency-domain, and nonlinear analyses of HRV, BPV as well as methods for coupling and interaction analyses. RESULTS: Changes in autonomic nervous system (ANS) tone are known to accompany various mental disorders. Depressive patients frequently complain of symptoms of ANS dysfunction, such as dry mouth, diarrhea, and insomnia. These clinical observations propose the assumption of altered autonomic dysfunction in these patients. In contrast to these clinical assumptions, inconsistent results have been found in studies of HRV in depressive patients. This work therefore covers a brief review of the literature in respect to bipolar disorder and the rationale to study autonomic changes in such a psychiatric disease. CONCLUSIONS: Prospective studies of cardiovascular changes in mania and depression are needed to evaluate a psychopathological state in connection with cardiovascular changes and cardiac morbidity and mortality. These studies should consider BPV, coupling and interaction analyses, the application of nonlinear methods, and a multivariate approach in addition to the traditional analysis of HRV.

Autonomic Nervous System↗

PubMed2006

Status of infection control policies and organisation in European hospitals, 2001: the ARPAC study.

Patient safety in hospital care depends on effective infection control (IC) programmes. The Antimicrobial Resistance Prevention and Control (ARPAC) study assessed the organisation, components and human resources of IC programmes in European hospitals. A questionnaire survey of policies and procedures implemented in 2001 for the surveillance and control of nosocomial infection and antibiotic resistance was completed by 169 acute-care hospitals from 32 European countries, categorised by five geographical regions. A formal IC programme existed in 72% of hospitals, and a multidisciplinary IC committee was operational in 90%. Trained IC nurses (ICNs) were present in 80% of hospitals (ranging from 54% in south-east and central-eastern Europe, to 100% in northern Europe), whereas 74% had one or more trained IC doctors (ICDs) (ranging from 46% in south-east Europe to 84% in western Europe). Median staffing levels were 2.33 ICNs/1,000 beds and 0.94 ICDs/1,000 beds. The intensity of IC programmes scored higher in centres from northern and western Europe than from other European regions. Written guidelines promoted hand hygiene for healthcare workers in 89% of hospitals, education in 85%, and audit in 46%. Guidelines recommended use of alcohol-based solutions (70%) and/or medicated/antiseptic soap (43%) for decontamination of non-soiled hands. Use of alcohol-based solutions varied according to region, from 41% in southern Europe to 100% in northern Europe, compared with use of medicated soap from 77% in southern Europe to 11% in northern Europe (p < 0.01). These findings showed that IC programmes in European hospitals suffer from major deficiencies in human resources and policies. Staffing levels for ICNs were below recommended standards in the majority of hospitals. Education programmes were incomplete and often not supported by audit of performance. Hand hygiene procedures were sub-standard in one-third of centres. Strengthening of IC policies in European hospitals should be a public health priority.

Cross Infection↗

PubMed2005

Surgical smoke and infection control.

Gaseous byproducts produced during electrocautery, laser surgery or the use of ultrasonic scalpels are usually referred to as 'surgical smoke'. This smoke, produced with or without a heating process, contains bio-aerosols with viable and non-viable cellular material that subsequently poses a risk of infection (human immunodeficiency virus, hepatitis B virus, human papillomavirus) and causes irritation to the lungs leading to acute and chronic inflammatory changes. Furthermore, cytotoxic, genotoxic and mutagenic effects have been demonstrated. The American Occupational Safety and Health Administration have estimated that 500000 workers are exposed to laser and electrosurgical smoke each year. The use of standard surgical masks alone does not provide adequate protection from surgical smoke. While higher quality filter masks and/or double masking may increase the filtration capability, a smoke evacuation device or filter placed near (2-5 cm) the electrocautery blade or on endoscope valves offers additional (and necessary) safety for operating personnel and patients.

Air Pollutants, Occupational↗

PubMed2005

Diagnosing aortic valve stenosis by correlation analysis of wavelet filtered heart sounds.

Traditional auscultation performed by the general practitioner remains problematic and often gives significant results only in a late stage of heart valve disease. Valve stenoses and insufficiencies are nowadays diagnosed with accurate but expensive ultrasonic devices. This study aimed to develop a new heart sound analysis method for diagnosing aortic valve stenoses (AVS) based on a wavelet and correlation technique approach. Heart sounds recorded from 373 patients (107 AVS patients, 61 healthy controls (REF) and 205 patients with other valve diseases (OVD)) with an electronic stethoscope were wavelet filtered, and envelopes were calculated. Three correlations on the basis of these envelopes were performed: within the AVS group, between the groups AVS and REF and between the groups AVS and OVD, resulting in the mean correlation coefficients rAVS, rAVSv.REF and rAVSv.OVD. These results showed that rAVS (0.783 +/- 0.097) is significantly higher (p < 0.0001) than rAVSv.REF (0.590 +/- 0.056) and rAVSv.OVD (0.516 +/- 0.056), leading to a highly significant discrimination between the groups. The wavelet and correlation-based heart sound analysis system should be useful to general practitioners for low-cost, easy-to-use automatic diagnosis of aortic valve stenoses.

Adult↗

PubMed2005

Staphylococcus aureus carriage among participants at the 13th European Congress of Clinical Microbiology and Infectious Diseases.

The aim of this study was to measure the rate of Staphylococcus aureus nasal colonization among attendees of the 13th European Congress of Clinical Microbiology and Infectious Diseases (ECCMID), particularly with regard to methicillin-resistant (MRSA) strains. The 31.4% rate of Staphylococcus aureus colonization detected among the participants was in line with colonization rates reported previously for healthcare workers. A statistical difference was found between the rates of Staphylococcus aureus carriage in physicians (37.4%) and non-physicians (21.7%) but not between males (35.0%) and females (28.9%). Only one participant (a Belgian physician) was found to carry MRSA. Surprisingly, the rate of methicillin-susceptible Staphylococcus aureus carriage was significantly higher among participants from countries with a low prevalence of MRSA.

Carrier State↗

PubMed2005

Dutch guideline for preventing nosocomial transmission of highly resistant microorganisms (HRMO).

Hospitals are faced with the increasingly rapid emergence and dissemination of antimicrobial-resistant microorganisms. US and European guidelines on the prevention of antimicrobial resistance in hospitals were, until recently, mainly directed at methicillin-resistant Staphylococcus aureus (MRSA). In 2004, the Dutch Working Party on Infection Prevention issued a guideline on the prevention of nosocomial transmission of highly resistant microorganisms (HRMO), in order to fulfill the growing need for additional guidance on the control of other pathogens with acquired resistance and the potential to spread within hospitals (such as glycopeptide-resistant Enterococcus faecium, penicillin-resistant Streptococcus pneumoniae, extendedspectrum beta-lactamase producing Enterobacteriaceae, and other (multi)drug-resistant gram-negatives). In addition to providing criteria for defining HRMO, the Dutch guideline provides recommendations on isolation of patients, active surveillance, and contact tracing. The guideline will enable the comparison of HRMO rates between hospitals, and may be used to evaluate the efficacy of programs to control antibiotic use and/or nosocomial transmission of resistant pathogens. The eventual success of nationwide implementation of this guideline remains to be established in the coming years.

Cross Infection↗

PubMed2005

[Sex/Gender research -- introduction and anesthesiological aspects].

On the one hand gender studies are based on the differentiation of biological (sex) and social (gender) identities. Above all, gender studies in public health research are seen as an biological, psychological and social entity. To understand the complexity linked to the term "gender" in medicine, different perspectives are required. Apart from the uncertainty, which may occur by the changing perspective on gender, it also holds the option for innovation in anesthesiology, too. The goal of gender based medicine is an optimized, individual adjusted medical care. Precondition to realize this aim is the understanding of the genesis, the consolidation, and the elimination of gender biases in all fields of research, publications and education. The transfer of methods and guidelines for gender sensitive research, adapted from the public health research, allows an access to detect the meaning of gender specifics and gender differences, to verify its clinical relevance and to exercise the results in clinical daily work. With gender sensitive methods desiderata should be reduced, and methodological standards for gender sensitive medical/clinical research can be developed and implemented into medical education. In the light of knowledge about sex specific differences in pharmacokinetic and pharmacodynamic as well as undesired drug interactions, basic research may help to overcome the gender gap and to individualize and optimize the anesthesiological approach as well. A main problem in implementing gender studies into medicine is the limitation of sex sensitive biomedical significance. Nevertheless, the already existing measures in public health should be evaluated and modified for clinical practice. The current review is to be read as an introduction into different aspects of gender studies in medicine, in order to extend the understanding of its importance for anesthesiology, too. It shows that the relevance transcends still existing studies based on biomedical gender diversities.

Adult↗

PubMed2005

Optimized symbolic dynamics approach for the analysis of the respiratory pattern.

Traditional time domain techniques of data analysis are often not sufficient to characterize the complex dynamics of respiration. In this paper, the respiratory pattern variability is analyzed using symbolic dynamics. A group of 20 patients on weaning trials from mechanical ventilation are studied at two different pressure support ventilation levels, in order to obtain respiratory volume signals with different variability. Time series of inspiratory time, expiratory time, breathing duration, fractional inspiratory time, tidal volume and mean inspiratory flow are analyzed. Two different symbol alphabets, with three and four symbols, are considered to characterize the respiratory pattern variability. Assessment of the method is made using the 40 respiratory volume signals classified using clinical criteria into two classes: low variability (LV) or high variability (HV). A discriminant analysis using single indexes from symbolic dynamics has been able to classify the respiratory volume signals with an out-of-sample accuracy of 100%.

Algorithms↗

PubMed2005

The training curriculum in hospital infection control.

Standardised training curricula for infection control nurses (ICNs) and recognition of the specialty exist in many European countries, but infection control physician (ICP) is not a specialty recognised by the UEMS. To gather information on curricula for ICPs, members of the ESCMID Study Group on Nosocomial Infections received a questionnaire. There is discussion about which 'professions' should be included in an infection control team. Within the 12 countries included, the average full-time equivalents (FTEs) for ICPs and ICNs per 1000 beds were 1.2 and 3.4, respectively. In addition to ICNs and ICPs, an infection control team should also include a data manager, an epidemiologist, secretarial/administrative support, and possibly, surveillance technicians. Overall, the composition of an ideal infection control team was estimated to be 9.3 FTE per 1000 beds. The background of ICPs can be clinical microbiology or infectious diseases. Among the participants, it was predominantly clinical microbiology. The ideal training curriculum for the ICP should include 6 years of postgraduate training. Of these, at least 2 years should be 'clinical training' (e.g., internal medicine) to acquire experience in the management of high-risk patients. Furthermore, training with regard to infection control and hospital epidemiology should be offered as a 'common trunk' for those being trained in clinical microbiology or infectious diseases. Important issues that remain are: implementation/standardisation of training curricula for doctors, recognition of ICP as a separate specialty or sub-specialty of clinical microbiology and/or infectious diseases, validation of on-the-job training facilities in terms of the number of doctors and nurses who can give training and the category of patients/problems present, and mandatory postgraduate education/continuing medical education specific for infection control for doctors and nurses in the field.

Cross Infection↗

PubMed2005

Detection of coronary microembolisation by Doppler ultrasound during percutaneous coronary interventions.

OBJECTIVE: To validate an intracoronary Doppler ultrasound device for high intensity transient signals (HITS) detection and to assess the incidence of HITS during percutaneous coronary intervention (PCI). METHODS AND RESULTS: In an in vitro model, particle count and number of HITS detected by an intracoronary 0.014 inch Doppler wire were closely correlated (r = 0.97, p < 0.001). In the clinical study, 32 patients (mean (SD) age 61 (11) years; 23 men, nine women) with coronary artery disease were treated with balloon dilatation and stent implantation for a single vessel stenosis. In these patients HITS were detected during PCI in 84% (27 of 32). Reproducibility (r = 0.99, p < 0.001) and interobserver agreement (r = 0.84, p < 0.001) of HITS counts were significant. The number of HITS after stent implantation was significantly higher than after balloon dilatation (11 (7) v 2 (4), p < 0.001). Postprocedural coronary flow velocity reserve (CFVR) was < 2.0 in 55% (16 of 29) of all patients after balloon dilatation and < 2.0 in 23% (six of 26) after stent implantation. The number of HITS after stent implantation did not differ significantly between patients with CFVR < 2.0 and patients with CFVR > or = 2.0 (12 (8) v 10 (7), not significant). CONCLUSIONS: Embolic particles can be detected as HITS by an intracoronary Doppler ultrasound device. Coronary microembolism is often observed during PCI, especially after stent implantation. However, the incidence of HITS alone does not explain a reduced CFVR after PCI.

Adult↗

PubMed2004

Low prevalence of methicillin-resistant Staphylococcus aureus (MRSA) at hospital admission in the Netherlands: the value of search and destroy and restrictive antibiotic use.

In the Netherlands, less than 1% of clinical isolates of Staphylococcus aureus are methicillin-resistant (MRSA). A national search and destroy policy prevents MRSA from becoming endemic. Some MRSA outbreaks cannot be related to patients at risk for MRSA carriage. This study was designed to measure the prevalence of MRSA among patients without risk factors for MRSA carriage at the time of admission to the hospital. In four Dutch hospitals, patients admitted to non-surgical departments in the period 1999-2000 were screened for MRSA nasal carriage. Nasal swabs were streaked on 5% sheep blood agar (BA), submerged in a selective broth, and incubated for two to three days at 35 degrees C. Colonies suspected of being S. aureus were identified with an agglutination test. Susceptibility testing was performed by an automated system and additional oxacillin disk diffusion. Methicillin resistance was confirmed by a DNA hybridization test and mecA PCR. MRSA strains were genotyped by pulsed-field gel electrophoresis (PFGE). Twenty-four percent (2332/9859) of the patients were S. aureus nasal carriers. Only three (0.03%) patients were MRSA carriers. These patients were not repatriated, nor known to be MRSA carriers before screening. Genotyping revealed that the strains were not clonally related and were not related to MRSA outbreaks in the hospital where the patients were admitted. We conclude that at routine admission to a Dutch hospital (excluding high-risk foreign admissions) the MRSA prevalence is low (0.03%), due to the Dutch search and destroy policy and restrictive antibiotic prescribing.

Carrier State↗