Biomedical subjects

Robert W Kreis

Publications and source records attributed to Robert W Kreis.

11 recordsLinked to original sources

PubMed2005

Analysis of the pre-incident education and subsequent performance of emergency medical responders to the Volendam café fire.

OBJECTIVE: At this moment, in the Netherlands, rescue workers are not given any specific standardized training in disaster response or disaster management. After the café fire in Volendam, the Netherlands, on New Year's Eve 2000, around 200 rescue workers were deployed on-site. The aim of this study is to investigate the rescue workers' experiences with regard to their level of preparation for the emergency response. METHODS: In 2002, 30 members of the medical and paramedical personnel were requested to participate in a structured interview, focused on education, task perception, triage and registration. RESULTS: Twenty-seven participated. Twenty-two rescue workers received previous training in emergency medicine. During the alarm phase, 11 rescue workers had a clear perception of their tasks. Twenty-four were involved in triage and injury assessment. Three rescue workers used a protocol for triage and 15 for injury assessment. Twenty-five rescue workers gave on-scene treatment and 15 used a protocol. Eight registered their findings. CONCLUSIONS: Preparation for the emergency response lacked standardized procedures. The use of triage protocols was extremely poor, as was documentation of actions. Slightly more than half of the personnel followed treatment protocols. It is advisable that all rescue workers become familiar with the basic uniform principles and protocols regarding disaster management. A dedicated and standardized national disaster management course is needed for all rescue workers.

Emergency Medical Services↗

PubMed2005

Management of multiple burn casualties from the Volendam disaster in the emergency departments of general hospitals.

OBJECTIVE: To establish the level of medical care provided in the emergency department of general hospitals to the victims of the Volendam café fire on 1 January 2001. METHODS: A retrospective review was done based on a standardized chart, for all victims seen at the emergency departments of 19 hospitals. Diagnostic findings and logistic aspects were inventoried. Treatment described in the Emergency Management of Severe Burns protocol was used as a gold standard against which the care provided to the victims was assessed. RESULTS: Data from 233 patients were included in the analysis. The documentation rate was low. Suspected inhalation injury and burns were the most frequently documented diagnoses. Most patients with suspected inhalation injury, for whom treatment records were available, received oxygen therapy (81%). Intubation was performed in 43% of patients with suspected inhalation injury and 14% of the remaining patients required intubation after admission to the intensive care unit. Most patients with circulatory problems (83%) and/or more than 15% of total body surface area burned (97%), for whom treatment records were available, received intravenous lines. Pain treatment seemed to have had low priority. Two patients (3%) were re-admitted after having been released earlier from the emergency department. CONCLUSION: Treatment and triage of the burn casualties after the Volendam café fire was adequate. The documentation rate was low. Not all steps in diagnosis and treatment may be of equal importance in disaster circumstances.

Adolescent↗

PubMed2004

Skin elasticity meter or subjective evaluation in scars: a reliability assessment.

UNLABELLED: Various methods are available for evaluating the elasticity of scars. However, the reliability and validity of these methods have been sparsely examined. The aim of this study was to examine the reliability of the subjective evaluation of scar pliability, while at the same time testing the reliability of the measurements of a non-invasive suction device (Cutometer Skin Elasticity Meter 575) on scars. Four observers assessed 49 scar areas of 20 patients with a subjective assessment of pliability. Subsequently, each observer measured the scar areas with the Cutometer. The intraclass correlation coefficients (ICC) of the elasticity (Ue) and extension (Uf) parameters of the Cutometer were acceptable (r = 0.76 and 0.74, respectively) when a single observer carried out the measurements. The subjective assessment of pliability needs to be completed by two or more observers to make the evaluation reliable (r = 0.79). The concurrent validities between the subjective pliability-assessment and each of the Cutometer parameters were statistically significant and ranged from r = 0.29-0.53. The correlations between each of the Cutometer parameters were high and statistically significant (r > or = 0.71). CONCLUSION: A single observer can reliably use the Cutometer for the elasticity measurements of scars. Furthermore, either Ue or Uf, instead of all five elasticity values provided by the Cutometer, can be adequately used for the elasticity measurements of scars. The subjective assessment of pliability of scars can only be assessed reliably when completed by two or more observers. The concurrent validity showed that all Cutometer parameters, except for visco-elasticity (Uv), and the subjective assessment of pliability measured the same characteristic of a scar.

Adolescent↗

PubMed2004

Colour evaluation in scars: tristimulus colorimeter, narrow-band simple reflectance meter or subjective evaluation?

The evaluation of scar colour is, at present, usually limited to an assessment according to a scar assessment scale. Although useful, these assessment scales only evaluate subjectively the degree of scar colour. In this study, the reliability of the subjective assessment of scar colour by observers is compared to the reliability of the measurements of two objective colour measurement instruments. Four independent observers subjectively assessed the vascularisation and pigmentation of 49 scar areas in 20 patients. The degree of vascularisation and pigmentation was scored according to a scale ranging from '1', when it appeared to be like healthy skin, to '10', which corresponds to the worst imaginable outcome of vascularisation or pigmentation. The observers also scored the pigmentation categories of the scar (hypopigmention, hyperpigmention or mixed pigmentation). Finally, each observer measured the scar areas with a tristimulus colorimeter (Minolta Chromameter) and a narrow-band simple reflectance meter (DermaSpectrometer). A single observer could reliably carry out measurements of the DermaSpectrometer and the Minolta Chromameter for the evaluation of scar colour (r = 0.72). The vascularisation of scars could also be assessed reliably with a single observer (r = 0.76) whereas for a reliable assessment of pigmentation at least three observers were necessary (r > or = 0.77). The agreement between the observers for the pigmentation categories also turned out to be unacceptably low (k = 0.349). This study shows that an overall evaluation of scar colour with the DermaSpectrometer and the Minolta Chromameter is more reliable than the evaluation of scar colour with observers. Of both instruments for measuring scar colour, we prefer, because of its feasibility, the DermaSpectrometer.

Adolescent↗

PubMed2004

The patient and observer scar assessment scale: a reliable and feasible tool for scar evaluation.

At present, various scar assessment scales are available, but not one has been shown to be reliable, consistent, feasible, and valid at the same time. Furthermore, the existing scar assessment scales appear to attach little weight to the opinion of the patient. The newly developed Patient and Observer Scar Assessment Scale consists of two numeric scales: the Patient Scar Assessment Scale (patient scale) and the Observer Scar Assessment Scale (observer scale). The patient and observer scales have to be completed by the patient and the observer, respectively. The patient scale's consistency and the observer scale's consistency, reliability, and feasibility were tested. For the Vancouver Scar Scale, which is the most frequently used scar assessment scale at present, the same statistical measurements were examined and the results of the observer scale and the Vancouver scale were compared. The concurrent validity of the observer scale was tested with a correlation to the Vancouver scale. Furthermore, the authors examined which specific characteristics significantly influence the general opinion of the patient and the observers on the scar areas. Four independent observers have each used the observer scale and the Vancouver scale to assess 49 burn scar areas of 3 x 3 cm belonging to 20 different patients. Subsequently, the patients completed the patient scale for their scar areas. The (internal) consistency of both the patient and the observer scales was acceptable (Cronbach's alpha, 0.76 and 0.69, respectively), whereas the consistency of the Vancouver scale appeared not to be acceptable (alpha, 0.49). The reliability of the observer scale completed by a single observer was acceptable (r = 0.73). The reliability of the Vancouver scale completed by a single observer was lower (r = 0.69). The observer scale showed better agreement than the Vancouver scale because the coefficient of variation was lower (18 percent and 22 percent, respectively). The concurrent validity of the observer scale in relation to the Vancouver scale is high (r = 0.89, p < 0.001). Linear regression of the general opinions on scars of the observer and the patient showed that the observer's opinion is influenced by vascularization, thickness, pigmentation, and relief, whereas the patient's opinion is mainly influenced by itching and the thickness of the scar. Such an impact of itching and thickness of the scar on the patient's opinion is an important and novel finding. The Patient and Observer Scar Assessment Scale offers a suitable, reliable, and complete scar evaluation tool.

Adolescent↗

PubMed2004

Reliability and accuracy of techniques for surface area measurements of wounds and scars.

The applicability of simple methods to measure the size of pathological skin lesions for management and research has been poorly studied to date. The interobserver reliability and accuracy (validity) was established for planimetry by photography and planimetry by tracing on a transparent sheet in this study. Drawings of 25, 50, and 75 cm(2) were created on 3 locations with increasing curvature (back, thigh, and forearm) in 20 healthy volunteers. Three investigators evaluated the drawings by both planimetry techniques. Both techniques showed a good reliability (r >or= 0.82, intraclass correlation) for 25 cm(2) areas. Planimetry by photography was more reliable than planimetry by tracings for the 50 -and 75-cm(2) areas and was more accurate than planimetry by tracing for all areas except for the area with the greatest curvature, the forearm. The study permits the conclusion that planimetry by photography is more suitable for surface area measurements than planimetry by tracing except for extremely curved body parts, where it is likely that effects of distortion supervene.

Journal Article↗

PubMed2003

Collagen morphology in human skin and scar tissue: no adaptations in response to mechanical loading at joints.

Dermal collagen displays a random-like structure that has a major role in strength and function of the human integument. It is hypothesised that collagen bundles align in a parallel fashion in the direction of mechanical tension during scarring, which may explain the problematic scar formation that occurs specifically at joints. Scar tissue and normal skin were biopsied from joints and control areas and evaluated by the Fourier analysis. Collagen orientation was represented by an index ranging from 0 (perfectly random) to 1 (perfectly parallel). Collagen bundle packing signifies the average distance between the centres of collagen bundles. No differences were shown in collagen morphology of scar tissue and normal skin between joints and control areas. Normal skin had a significantly lower collagen orientation index than scar tissue (0.26 versus 0.44, P<0.001). The bundle packing of scar tissue differed significantly from normal skin (18.1 microm versus 23.7 microm, P<0.001). Collagen appeared less parallel orientated in deep dermis compared to superficial dermis especially for normal skin (0.27 versus 0.33, P=0.06). Normal skin had a less parallel organisation in sections that were cut parallel compared to those that were cut perpendicular to the epidermis (0.24 versus 0.30, P=0.02). Collagen orientation of scar tissue is more parallel compared to normal skin. Morphology differs with respect to superficial and deep dermal layers and parallel and perpendicular planes, but appears not to respond to mechanical tension.

Adult↗

PubMed2002

Morphometry of dermal collagen orientation by Fourier analysis is superior to multi-observer assessment.

In human dermis, collagen bundle architecture appears randomly organized, whereas in pathological conditions, such as scar tissue and connective tissue disorders, collagen bundle architecture is arranged in a more parallel fashion. Histological examination by one or two observers using polarized light is the most common method to determine collagen orientation. The hypothesis on which this study is based is that an objective image analysis technique, Fourier analysis, would improve the reliability (are the measurements reproducible?) and the accuracy (does the method measure what it is supposed to measure?) of collagen orientation assessment, compared with observer ratings. Fourier analysis was applied to 271 images of scar tissue and normal skin that were acquired by confocal laser-scanning microscopy. Observers rated the same areas using polarized light as well as the confocal microscopy images. Computer images consisting of different types of ellipses were generated with a fixed orientation. Observers and Fourier analysis evaluated the images to evaluate accuracy. The inter-observer reliability was acceptable when at least three observers rated polarized light images (r > 0.69), whereas two observers were sufficient for rating confocal microscopy images (r > 0.71). Fourier analysis correlated better with observer ratings of confocal microscopy images (r = 0.69) than with polarized light microscopy images (r = 0.42). Fourier analysis was more accurate than four observers for the evaluation of the 'true' orientation for almost all types of computer-generated images. For the first time it is shown that Fourier image analysis is suitable for the morphometry of dermal collagen orientation and leads to a superior measurement of collagen orientation compared with subjective histological evaluation by several experts. If an evaluation is performed by conventional light microscopy, at least three observers are required to attain an acceptable inter-observer reliability.

Adult↗

PubMed2002

Long-term results of a clinical trial on dermal substitution. A light microscopy and Fourier analysis based evaluation.

Although dermal substitution is a main topic of current wound healing research, there is a paucity of clinical trials with a long-term clinical and histopathological evaluation. A clinical trial was conducted to perform an intra-individual comparison of conventional treatment (split-thickness autograft) to a collagen/elastin dermal substitute in combination with an autograft. Promising results with this substitute were obtained with respect to dermal organisation and scar elasticity in animal studies and clinical trials with a short-term follow-up. Twenty-nine of the 42 pairs of the burn wounds and 28 of the 44 pairs of the scar reconstructions enrolled in the study were biopsied after 1 year. Promising but not statistically significant differences were found between substituted groups and control groups for epidermal thickness, basement membrane maturation, rete ridges (P=0.055), fibroblasts, myofibroblasts, inflammatory cells, vessels and extracellular matrix maturation. An objective and accurate technique, Fourier analysis, was used to evaluate collagen bundle orientation and packing. However, no statistically significant differences were obtained for these parameters. This microscopic evaluation provided no convincing evidence for a long-term effectiveness of a dermal substitute despite promising data over a short-term in in vitro and in vivo studies with the same material.

Adult↗

PubMed2002

Scar assessment tools: implications for current research.

Scarring is considered a major medical problem that leads to cosmetic and functional sequelae. Scar tissue is clinically distinguished from normal skin by an aberrant color, rough surface texture, increased thickness (hypertrophy), occurrence of contraction, and firmness. Marked histologic differences are the change in dermal architecture and the presence of cells such as the myofibroblast. Many assessment tools are available for analysis of pathologic conditions of the skin; however, there is no general agreement as to the most appropriate tools for evaluation of scar tissue. This review critically discusses currently available objective measurement tools, subjective assessment tools, and potential devices that may be available in the future for scar assessment.

Cicatrix↗

PubMedDate not supplied

Administration of prednisolone phosphate-liposomes reduces wound contraction in a rat partial-thickness wound model.

Macrophages play an important role in the inflammatory phase of wound healing and their activity regulates fibroblasts and keratinocytes. Modulation of macrophage function may result in improvement of the wound healing process. Prednisolone phosphate (PLP) encapsulated into liposomes was administered to partial-thickness wounds in rats. A single dose of 75 microg/kg, applied directly after wounding, resulted in up to a 30% reduction of wound contraction at 28 days after wounding. This effect could not be achieved in the group that was administered free PLP or liposomes containing phosphate-buffered saline to the wound. The number of myofibroblasts was up to 50% lower in wounds treated with the liposomal PLP at 4 days after wounding. The number of macrophages present in the wounds was not statistically different between groups. Most probably, the production of cytokines and growth factors by macrophages is altered after phagocytosing the liposomes, resulting in reduced wound contraction.

Administration, Topical↗