Search PubMed⌕ Search

Biomedical subjects

W Kröll

Publications and source records attributed to W Kröll.

At least 19 recordsLinked to original sources
PubMed2000

Intestinal elimination of hydroxyethyl starch?

OBJECTIVE: Hydroxyethyl starch (HES) is mainly eliminated via the kidneys. Any information about extrarenal elimination obtained so far has been either incomplete or contradictory. The objective of this study was to quantify the intestinal excretion of infused HES with a mean molecular weight of 200,000 and a molar substitution of 0.5 (HES 200/0.5) and to compare the reappearance/recovery rate in urine and plasma. DESIGN: Prospective clinical study without control group. SETTING: The study was conducted at the Institute of Hypertension of the Society of Clinical Pharmacology, Vienna, Austria, which is an establishment for research in volunteers. PARTICIPANTS: The results of six out of seven healthy male volunteers were appropriate for analysis. One trial subject had to be excluded from the study because of severe protocol violation (mixing of stool and urine samples). INTERVENTIONS AND METHODS: Each volunteer was administered 500 ml of 10% HES 200/0.5 in a 0.9% NaCl solution intravenously within 1 h. A gut lavage with 6 l of a polysaccharide free solution was continuously administered from 3 h prior to until 2 h after the HES infusion to facilitate the collection of the samples and to exclude any source of error at analysis. HES was quantified with the hexokinase method. MEASUREMENTS AND RESULTS: Right from the beginning of the infusion until 10 h after its completion, the cumulative HES excretion with feces (principle parameter) and urine as well as selective plasma volume and HES plasma level were measured. Six and 14 h after the infusion had been completed, the recovery rates of HES in urine were about 30% and 40%, respectively, and in plasma about 23% and 8%, respectively. By contrast, not more than a kind of "background noise amount" of HES (about 0.2 %) could be recovered in feces ( mean value in % of the infused amount of the substance). Six and 14 h after the infusion had been completed, the total recovery rates of HES were 53% and 49%, respectively. CONCLUSION: In a physiologically unimpaired gut HES 200/0.5 is not, or only to an infinitesimal extent, eliminated via the intestine. The question if there is any alternative path to renal excretion for HES still remains to be answered. As the calculated reappearance/recovery rate of HES is only about 50 % of the administered dose, further investigations as to the final fate of HES appear necessary.

Adult↗
PubMed1998

[Hypertonic-hyperoncotic solutions: possibilities and limits].

Hypertonic-hyperoncotic solutions are a supplementary possibility in the acute treatment of hypovolemia. The main mechanism of action of this solution is, induced by the tonicity of the infusion (approximately 2400 mOsm/l), the transcapillary fluid shift from the intracellular and interstitial to the intravascular compartment. Additionally the fluidity of blood is improved (due to an increase in the diameter of the capillaries), the adherence of leucocytes to the endothelial wall is reduced, and the arteriolar vasomotion is restarted. Due to the available prehospital and clinical results it can be concluded, that hypertonic-hyperoncotic solutions offer advantages compared to conventional fluid therapy regimes: rapid stabilization of hemodynamics, reduction of posttraumatic volume deficiency, of posttraumatic edema and of posttraumatic complications and an improvement of the outcome of the patients. If the therapeutic recommendations are followed, such as a dose of 4 ml/kg body weight, infusion time of about 3-5 minutes and after the end of the infusion application of colloids or crystalloids in an amount as needed, no side effects will occur. Only immediately after the end of infusion sodium, chloride and osmolarity will slightly increase, however these parameters will normalize within the first posttraumatic day. Hypertonic-hyperoncotic solutions are trigger-solutions, as with the infusion of these types of solution it is possible to restore hemodynamics adequately and to prevent shock-induced complications.

Blood Volume↗
PubMed1997

Pain treatment in the ICU: intravenous, regional or both?

Adequate treatment of pain in ICU patients should be an integral part of ICU management, as inadequately treated pain leads to a series of complications that may counteract the success of ICU treatment. For continuous intravenous use we recommend sufentanil in a dose of 0.75-1.0 microgram kg-1 h-1 in mechanically ventilated patients and in a dose of 0.25-0.35 microgram kg-1 h-1 in intubated and spontaneously breathing patients. On-demand analgesia, administered via the intravenous or epidural route, may be an alternative to a relatively fixed continuous infusion of an analgesic drug, and in some ICU patients the transdermal use of opioids can be an alternative to continuous intravenous drug application or PCA. Increased sizes of the patch (25, 50, 75, 100 cm2) provide sustained transdermal rates of approximately 25, 50, 75 and 100 micrograms h-1 of fentanyl over a period up to about 72 hours. Patients with trauma to the thorax, pelvic fracture, or after major surgical interventions will be better managed by regional application of analgesic drugs alone or in combination with a systemic analgesic drug infusion. To achieve the best results it is necessary to be well informed and trained in the method, to know the advantages and disadvantages, the correct and modified dosages of the drugs used, and the indications and contraindications.

Administration, Cutaneous↗
PubMed1997

[Thyroid gland surgery in pregnancy].

Thyroid carcinoma is more frequent in younger women, but direct correlation with pregnancy is not proven. Preoperative management of suspect nodules reveals clear indications for immediate intervention. Out on 1471 thyroid operations, 340 female were in the group between 20 and 40 years. 53 carcinoma, i.e. 3.6%, in this subgroup had a potential concomittance of pregnancy and thyroid tumor. Although risk of obortion is very low in non-abdominal surgery, operations should be delayed post-partum except in cases of proven carcinoma.

Abortion, Spontaneous↗
PubMed1995

[Education of the medical student in first aid, emergency and disaster medicine--the Graz model].

In Austria emergency and disaster medicine is a young interdisciplinary subject. It is only a borderline discipline encompassing different medical subjects and was subdivided into emergency medicine for medical doctors only and first-aid for lay people and emergency technicians. In fact, since emergency medicine without first-aid can't be successful, the Department of Anaesthesiology at the University of Graz let all students of the medical faculty have a comprehensive education in the treatment of injured of acutely ill patients. According to the three steps of the study lectures and practices, all parts of first-aid, emergency and disaster medicine were offered. In spite of the short time since this has been running, we found a good acceptance and we hope to increase the interest evinced by medical students in our training programme.

Austria↗
PubMed1995

[Nephrogenic adenoma after kidney transplantation].

We report five cases of nephrogenic adenoma that arose several years after cadaver kidney transplantation. Cystoscopy was performed in all patients because of gross haematuria and revealed multifocal tumorous lesions in all parts of the bladder. On admission to of hospital graft function was satisfactory in all patients. There were three female and two male patients. In all patients the therapeutic procedure consisted of transurethral resection. Only very small lesions were fulgurated. Postoperatively an indwelling catheter was left in place for 2-4 days, and after a check on kidney parameters and immunosuppressive therapy all patients were discharged. Postoperative management consisted in cystoscopy every 3 months in the first year and then every 6 months. Though the etiology of nephrogenic adenoma remains unclear, mechanical traumatization and recurrent urinary tract infection seem to be the most important factors in its development.

Adenoma↗
PubMed1994

[Degree of substitution and volume expanding effect of various medium molecular weight hydroxyethyl starch solutions].

Hydroxyethylstarch (HES) is today one of the most frequently used artificial plasma substitutes in prehospital, as well as in clinical settings. However, there are no studies comparing the volume effect of different HES solutions. The goals of the present study therefore were to compare the volume effect of three HES solutions, which are similar with regard to mean molecular weight but different in concentration and degree of substitution. The obtained results enable guidelines for fluid resuscitation in hypovolemia to be laid down. In 30 patients fulfilling the ASA physical status classification I and II 500 ml of either 10% HES 200/0.5, 6% HES 200/0.5 or 6% HES 200/0.6-0.66 were infused within 30 min. The effect of each solution was evaluated using the mechanical oscillator technique (MOT). This technique measures precisely density changes of blood and plasma and allows-using standard formulae-calculation of blood and plasma volume changes. All 3 HES solutions showed similar effects in increasing plasma volume. Immediately after the end of infusion plasma volume was increased by about 800 ml with 10% HES and by about 650 ml with 6% HES 200/0.5. The volume expanding effect of 6% HES 200/0.6-0.66 amounted to 700 ml. The volume expanding effect of all starches decreased only slightly during the following two hours; an interesting detail observed was a second volume effect of HES (about 20% of the volume infused). We conclude that for the correlation of fluid deficits due to trauma, hemorrhage and shock HES solutions seem to be most effective artificial plasma substitutes.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Viscosity↗
PubMed1994

["Small volume resuscitation"--does it open new possibilities in the treatment of hypovolemic shock?].

Hypertonic-hyperoncotic solutions are a supplementation to conventional fluid regimens in the management of hypovolemia due to trauma, hemorrhage and shock. In this review the possible modes of action of these solutions are discussed and their efficacy both in experimental and clinical settings is presented. Possible side effects, such as hypernatremia and possible problems in the presence of increased intracranial pressure, following administration of hypertonic-hyperoncotic solutions are discussed, as well as the reaction of normovolemic patients to such infusions.

Blood Volume↗
PubMed1992

[The effect of 6% HES 200/0.6-0.66 on plasma volume and blood coagulation].

The main goal of the recent study was to evaluate changes in plasma volume due to the application of 6% HES 200/0.6-0.66. 12 patients according to the ASA physical status classification (I, II) undergoing minor surgical interventions received 500 ml of this artificial plasma substitute within 30 min. In a control group (n = 12), 500 ml of lactated Ringer's solution was given within the same period. A further question of the present investigation was the possible influence of 6% HES on coagulation during the following period (1st-3rd postoperative days). 6% HES 200/0.6-0.66 led to an additional augmentation of plasma volume measured via the mechanical oscillator technique of 200 ml (40% of the volume given) immediately at the end of infusion. A second increase in plasma volume of 100 ml (20% of the volume infused) could be observed 1 h later. With exception of the activity of factor VIII, the coagulation parameters had not been altered by infusion of 6% HES. The activity of factor VIII decreased to about 50% of the control level but showed a tendency to normalization within the following observation period. 6% HES 200/0.6-0.66 has a marked volume-expanding effect and exerts no influence on coagulation except a temporary decrease of factor VIII activity.

Adult↗
PubMed1992

[Is sufentanil suitable for long-term sedation of a critically ill patient?].

Sedation and analgesia are commonly practised in critically ill patients. The drugs and techniques used vary widely, however. Many reports have emphasized that analgesia has to be the primary goal in every therapeutic intervention in critically ill patients. The new narcotic sufentanil has been in use since 1987 in our intensive care unit. PATIENTS AND METHODS. Forty-nine patients in our ICU received sufentanil during controlled mechanical ventilation. The dose given was 0.75-1.0 micrograms.kg bw-1.h-1. In a second part of this study sufentanil was also administered to patients during the weaning period. The dose administered was 0.25-0.35 micrograms.kg bw-1.h-1. RESULTS. With sufentanil analgesia and sedation, most of our patients could be managed well; for only five patients the amount of sufentanil given was too small (Fig. 1). Sufentanil did not show any negative influence on haemodynamic variables, such as heart rate and mean arterial pressure; in addition, serum cortisol levels were not decreased (all values within normal range; Fig. 2); during the weaning phase sufentanil 0.25-0.35 micrograms/kg also proved to be excellent; paCO2 levels did not show any tendency to increase to abnormal levels (Fig. 3). CONCLUSIONS. Analgesia and sedation with sufentanil proved to be satisfactory in critically ill patients. In a dose range of 0.75-1.0 micrograms.kg bw-1.h-1 this drug can safely be given to patients undergoing controlled mechanical ventilation. Caution is necessary in hypovolaemic patients, in whom hypotension can occur if sufentanil is administered in the recommended dose. Sufentanil in a dose range between 0.25-0.35 micrograms.kg bw-1.h-1 is safe when given to patients during the weaning period.

Adolescent↗
PubMed1991

Communication during the pre-operative visit.

Eighty-six patients completed a questionnaire about what they expected from a pre-operative visit by an anaesthesiologist. Ninety-one per cent of the patients wanted a detailed and informative conversation. The patient's previous knowledge stemmed primarily from lay sources, such as other patients and visitors. Age and marital status influenced the extent of the patient's previous knowledge.

Adult↗
PubMed1990

[Perioperative subjective emotional state].

The aim of adequate preoperative medication is to minimize the patient's anxiety level. Preoperative anxiety can be consciously and specifically orientated or it can be masked. This double-blind study was performed to evaluate the effects of an anxiolytic drug in comparison with a placebo perioperatively and to assess the post-operative course of the important factors anxiety, depression and asthenia. The Mannheim inventory for subjective state and STAI (State-Trait-Anxiety-Inventory) were offered. The study was undertaken in 60 female patients, who were operated for suspected carcinoma of the breast. We conclude that in such a specific group of patients extensive preoperative psychological preparation must be backed up by the administration of an anxiolytic drug.

Adaptation, Psychological↗
PubMed1990

[New organ-preserving technics for third-grade splenic trauma. An experimental study].

We studied two new techniques for orthotopic preservation of the spleen in an animal model with respect to their technical feasibility and their hemostatic efficacy. This study was performed in two stages. In the first, the treatment of central bursting ruptures by splenorrhaphy using a resorbable compressive mesh was tested. 20 sheep have been used for this part of the study. They were divided into four groups (A: control, B: sham operation, C: splenectomy, D: mesh splenorrhaphy). Following completion of this stage, two animals from group A and two from group B were used to test a second experimental setting. Experimental trauma corresponding to isolated third degree polar rupture of the spleen was induced. This was then treated by a polar resection using stapling instruments. All animals from each stage were subjected to spleen scanning three months postoperatively, followed by splenectomy. The spleens were then examined histologically. Both macroscopically and microscopically normal splenic tissue was found. No difference between the different groups could be detected by laboratory investigations. Gamma-globulins and total serum proteins were within normal ranges after five weeks. Splenic scan revealed an excellent function of the pulp. Both techniques are distinguished by their facility and rapidity, as well as reliable hemostasis and minimal technical prerequisites.

Animals↗