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D Heise

Publications and source records attributed to D Heise.

At least 19 recordsLinked to original sources
PubMed2007

[Teaching and simulation. Methods, demands, evaluation and visions].

Since 1st October 2003 the new German "Approbationsordnung für Arzte" (Medical Licensing Regulations) requires an increasing amount of small group teaching sessions and encourages a multidisciplinary and more practical approach to the related topics. In 2004 the German Society of Anaesthesiology and Intensive Care Medicine has provided almost all anaesthesia faculties of German Universities with equipment for full-scale simulation. This article describes methods for a simulation-based medical education training program. Basic requirements for a successful training program using full scale simulators are the provision of an adequate logistical and material infrastructure, teacher attendance of train-the-trainer courses, implementation in the medical curriculum and an instructor-student ratio of 1:3, equivalent to that for bedside teaching. If these requirements were fulfilled, medical students scored the simulation scenarios "induction of anaesthesia", "acute pulmonary embolism", "acute management of a multiple trauma patient" and "postoperative hypotension" as 1.5, 1.6, 1.5 and 1.5, respectively, on a scale of 1-6. These scores were better than those given for other segments of the curriculum.

Anesthesia↗
PubMed2001

Leishmania major lipophosphoglycan modulates the phenotype and inhibits migration of murine Langerhans cells.

Langerhans cells (LC), members of the dendritic cell family, play a central role in the initiation and regulation of the immune response against the protozoan parasite Leishmania major. LC take up antigens in the skin and transport them to the regional lymph nodes for presentation to T cells. However, it is not known whether LC functions are modulated by parasite antigens. In the present study, we examined the effect of a major parasite surface molecule, L. major lipophosphoglycan (LPG), on the maturation of LC and their migratory properties. The results show that exposure to LPG did not affect the expression of major histocompatibility complex (MHC) class II and B7, but induced an up-regulation of CD25, CD31 and vascular endothelial (VE)-cadherin expression and a down-regulation of Mac-1 expression, by LC. Importantly, LPG treatment inhibited the migratory activity of LC, as it reduced their efflux from skin explants and their migration in transwell cultures. These results suggest that Leishmania LPG impairs LC migration out of the skin and thus may modulate their immunostimulatory functions, which require LC translocation from skin to lymph nodes.

Animals↗
PubMed1998

[Causes of failure and dangers in the use of motor driven infusion pumps. Accidental closure of the infusion system].

UNLABELLED: Syringe drivers are used in anaesthetics, intensive care and emergency medicine to deliver small volumes of highly potent drugs with continuous, constant and reproducible flow. For early recognition of interruptions of the drug delivery caused by occlusion of the infusion system, an alarm is triggered as soon as the system pressure exceeds a certain limit. The sensitivity of this alarm depends on the flow rate, type-specific cut-off pressure and the elastic parameters of the infusion system. The sudden release of pressure built up in the system after occlusion occurred can cause delivery of an uncontrolled drug bolus and hence an additional hazard. METHODS: Six syringe drivers that are widely used in clinical practice were tested for alarm delay and bolus delivery in the event of an occlusion in the system. First, the alarm pressures at flow rates of 10, 50 and 100 ml/h were measured. Then the alarm delay time and bolus volumes post-occlusion were assessed, using a basic infusion system (syringe + single infusion set). Finally, several alterations to the system like extension, tap battery with germ filters or branching were made and their impact on alarm delay and bolus volume measured. RESULTS: Because of the great differences in alarm pressures between the devices tested, there were marked differences in the alarm delay at same flow rates. Predictably, there was an indirect proportional link between alarm delay and flow rate. Using the basic infusion system, alarm delays between 23 s and 143 min were measured. In two of the tested syringe drivers, a pressure-release mechanism is activated with the pressure alarm, which prevented bolus application. In the other devices, release of the pressure in the occluded system caused boli of 0.5-7 ml. Variations in the actual syringe volume and insertion of a second connection tube had no impact on alarm delay and bolus volume. Tap batteries, parallel running syringe drivers or trapped air in the system, however, caused marked increase in both alarm delay (107%) and bolus volume (+147%). DISCUSSION: Unidentified occlusions of the system cause grave malfunctioning of syringe drivers. While applying highly potent drugs, the discontinuation of drug delivery with subsequent bolus application can cause vital danger to the patient. As a result of the significant time delays in the pressure alarms, the devices tested do not provide sufficient protection against unrecognized system occlusion. Syringe drivers with adjustable alarm pressure can be set close to the actual infusion pressure. A further important point is that one should aim at a reduction in the elastic properties of the infusion set because of the great impact on alarm delay and bolus volume.

Equipment Failure↗
PubMed1998

In-vitro differentiation of mature dendritic cells from human blood monocytes.

Representing the most potent antigen-presenting cells, dendritic cells (DC) can now be generated from human blood monocytes. We recently presented a novel protocol employing GM-CSF, IL-4, and IFN-gamma to differentiate monocyte-derived DC in vitro. Here, such cells are characterized in detail. Cells in culture exhibited both dendritic and veiled morphologies, the former being adherent and the latter suspended. Phenotypically, they were CD1a-/dim, CD11a+, CD11b++, CD11c+, CD14dim/-, CD16a-/dim, CD18+, CD32dim/-, CD33+, CD40+, CD45R0+, CD50+, CD54+, CD64-/dim, CD68+, CD71+, CD80dim, CD86+/++, MHC class I++/ , HLA-DR++/ , HLA-DP+, and HLA-DQ+. The DC stimulated a strong allogeneic T-cell response, and further evidence for their autologous antigen-specific stimulation is discussed. Although resembling a mature CD11c+ CD45R0+ blood DC subset identified earlier, their differentiation in the presence of the Th1 and Th2 cytokines IFN-gamma and IL-4 indicates that these DC may conform to mature mucosal DC.

Animals↗
PubMed1996

[Severe, accidental hypothermia: active rewarming with a simple extracorporeal veno-venous warming-circuit].

We report the case of a 35-year-old male who was admitted to the intensive care unit because of somnolence due to accidental hypothermia. Initial examination showed a Glasgow coma score of 10 and a rectal temperature of 27.4 degrees C. Because of stable circulatory conditions, there was no mandatory indication for rewarming by means of cardiopulmonary bypass. We rewarmed the patient with an extracorporeal veno-venous haemofiltration device combined with a countercurrent fluid warmer. An average increase in body temperature of 1.34 degrees Ch-1 could be obtained. We conclude that the described technique represents an effective and well-controllable method for treatment of hypothermia in patients with stable haemodynamic conditions. Because of the availability of the required equipment, this method can also be practised in hospitals without cardiac surgical departments and cardiopulmonary bypass facilities.

Adult↗
PubMed1995

[Tamm-Horsfall protein, alpha-1- and beta-2-microglobulin as kidney function markers in heart surgery].

After cardiac surgery, transient renal dysfunction often occurs. Regional differentiation of these processes is possible only using invasive techniques, including renal biopsy. Approximately 30 different plasma protein components have been identified in the urine of healthy individuals by means of qualitative and quantitative immunochemical methods. The detection of microalbuminuria has high diagnostic relevance for the early diagnosis of renal damage at a reversible stage. One typical urinary protein is Tamm-Horsfall protein (THp). After histochemical staining of human kidney sections, activity is seen in the loop of Henle and initial distal tubule. The assay of alpha-1 microglobulin (MG) in urine is considered one of the most efficient laboratory parameters for the diagnosis of tubular lesions. Serum concentrations of alpha-1 MG are less dependent on extrarenal changes than are those of other low-molecular-weight proteins. beta-2 MG is also one of the standards used in recent years for diagnostic relevance. Urinary albumin excretion, normally less than 30 mg per day, sometimes increases after glomerular damage. Some renal function tests are used daily in many intensive care units, e.g. creatinine clearance (CCr) or urea and sodium excretion. Renal dysfunction should, however, be further examined to localise regional damage and to seek new clinical standards in addition to the conventional tests. METHODS. After obtaining the agreement of the local ethics committee, 30 patients were divided into two groups of 15 each: group I without renal dysfunction and CCr more than 60 ml/min; and group II with CCr below 60 ml/min. THp and alpha-1 MG were measured pre- and postoperatively after open heart surgery with the ELISA and beta-2 MG with the nephelometric technique. These parameters were compared with clinical standards such as albumin excretion, blood urea nitrogen (BUN), urea clearance, and fractional sodium excretion. RESULTS. The CCr did not change in group I from the pre- to postoperative period (81.5 to 85.1 and 91.4 ml/min), nor did excretion of THp (20.1 to 25.0 and 24.8 mg/day), correlation r = 0.7; P < 0.001). The elimination of alpha-1 and beta-2 MG was significantly higher in the postoperative period in this group (alpha-1: 7.2 to 44.1 and 100.6 mg/day; beta-2: 0.3 to 2.1 and 3.2 mg/day). In group II CCr showed pathological values (36.8 to 31.1 and 36.3 ml/min), as did simultaneous THp (13.5 to 9.7 and 12.7 mg/day). alpha-1 and beta-2 MG values became more pathological in the postoperative period than in group I (alpha-1: 32.8 to 113.9 and 198.5 mg/day; beta-2: 0.7 to 5.8 and 16.9 mg/day). DISCUSSION. Measurement of the excretion of THp and alpha-1 and beta-2 MG is a useful addition to present clinical standards for recognising early changes in renal function. The increases in the postoperative period after cardiac surgery showed tubular damage even in patients without predictive risk factors or clinical signs. In patients with renal dysfunction open heart surgery and extracorporeal circulation led to significant tubular damage.

Aged↗
PubMed1990

An expert system for synoptic interpretation of lung function tests.

We simulate the interpretation process by the testing of preformed working hypotheses. A clinical syndrome, "bronchial obstruction," is described by a set of suitable parameters (FEV1, MMEF, Raw, etc.). For a given patient, this set forms a normalized vector. It has to be compared with equivalent data derived from patients which fulfilled the criteria for the clinical syndrome in question. If the patient's vector has a similar direction as the vector of the collective, the working hypothesis is accepted. The length of the vector is then used to quantify the severity of the functional disturbances in verbal terms ("slight," "moderate," "severe"). The limits used for severity grading and the typical parameter pattern for the given syndrome are adapted to the user's criteria by a built-in learning capability. On the other hand, the assembled data may be used for the training of newcomers. The use of vector algorithms allows for a high flexibility of our program with respect to all methods used in lung function testing.

Algorithms↗
PubMed1990

[The histamine provocation test: are 1 second capacity and specific conductance competing or complementary measurement values?].

We tested criteria for the decision, whether a provocation challenge with histamine is positive. The combination of spirometry and bodyplethysmography by the condition sGaw less than or equal to 0.04 x PC-FEV overcomes the contradictions due to conventional criteria as PC-FEV greater than or equal to 20% or PC-sGaw greater than or equal to 50%.

Airway Obstruction↗