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H Nolte

Publications and source records attributed to H Nolte.

At least 73 records · Page 4Linked to original sources
PubMed1990

[Do elevated blood and cerebrospinal fluid glucose levels and other factors modify the density of cerebrospinal fluid and the spread of isobaric spinal anesthesia?].

When isobaric spinal anesthesia is applied the level of analgesia is of special interest. This level is influenced by many factors of varying importance. One major factor is the relation between cerebrospinal fluid (CSF) density and the density of local anesthetic solutions. The density of CSF changes with the concentrations of its constituents, e.g., glucose or protein. Because glucose concentrations in CSF change in parallel with blood glucose levels, this may have effects on CSF density and the spread of spinal anesthesia. In 43 patients in two groups (diabetic n = 32, non-diabetic n = 11) the influence of CSF density on the analgesia level achieved with isobaric spinal anesthesia was investigated with special reference to increased glucose levels in blood and CSF. The influence of body height and weight, age and CSF protein content were also studied. There were no statistically significant correlations between any of these factors and the extension of analgesia. The mean blockade level was 1.6 segments lower in the non-diabetic group: this difference was statistically not significant (P greater than 0.05). Anesthesia spread faster in the diabetic group, but this difference was also not significant (P greater than 0.05). For bupivacaine 0.5% alone a density of 1.0010 g/cc was found, while for bupivacaine 0.5% with epinephrine (1:200,000) the density measured was 1.0022 g/cc. There is no correlation (r2 = 0.083) between CSF glucose concentration and CSF density, other factors such as sodium, chloride or CO2, apparently being more important. With CSF density ranging between 1.000 and 1.003 g/cc there was no correlation with the blockade level (r2 = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

[Cutaneous blood flow following subcutaneous infiltration of lidocaine with and without the addition of adrenaline or ornipressin].

The addition of ornipressin to local anesthetics increases the duration of regional anesthesia. A dose of 0.1 unit/ml produces an increase in nerve block duration comparable to adrenaline 5 micrograms/ml. In order to suppress intraoperative bleeding higher concentrations of ornipressin have been used in infiltration anesthesia. This study was designed to examine whether an increase in ornipressin concentration above 0.1 unit/ml causes a further reduction in cutaneous blood flow. Twelve volunteers took part in the study. They received intracutaneous infiltrations of 4 ml lidocaine 0.5% in the volar aspects of both forearms (Fig. 1). The solution was either plain (= Lido) or contained adrenaline 5 micrograms/ml (Lido + A), or ornipressin 0.1 unit/ml (Lido + P1) or 0.2 unit/ml (Lido + P2). Blood flow was measured with a laser Doppler flowmeter; before the infiltration the skin was locally heated to 40 degrees C in order to obtain maximal perfusion (Flow 100); this temperature was maintained throughout the measuring period. The minimal flow after infiltration was calculated as a percentage of Flow 100. Lido caused a significant decrease in flow to 59 +/- 25% (M +/- SD). Lido + A, Lido + P1 and Lido + P2 caused further significant flow reductions, to 19 +/- 21%, 23 +/- 16% and 26 +/- 23%, respectively (Figs. 3, 4). The latency of maximal flow reduction did not differ between the four solutions (Fig. 5). The results show that in infiltration anesthesia an increase in ornipressin concentration above 0.1 unit/ml does not improve superficial vasoconstriction.

Anesthetics, Local↗
PubMed1989

Passive sensitization of human intestinal mast cells.

Dispersed human intestinal mast cells were used for passive sensitization experiments. Eight biopsies (9.7 +/- 1.2 mg/biopsy) of human duodenum were collected from non-atopic children (5) and adults (5). The tissue was dispersed mechanically and enzymatically to yield single cell suspensions. The method produced 2 x 10(3) mast cells per mg wet weight of tissue in a purity of 2.8%. Passive sensitization of the mast cells was performed with the patients' own plasma and plasma obtained from atopic donors. The non-atopic mast cells were able to bind the allergen-specific IgE. In addition, passive sensitization with atopic donor-plasma enhanced the cell sensitivity and cell reactivity to anti-IgE challenge, but had no effect on the cellular response to the ionophore A23187. The study shows that the enzymatic dispersion of human intestinal mast cells produces functionally intact mast cells with preserved Fc-receptors which can be passively sensitized.

Aged↗
PubMed1989

Phase II study of tauromustine in disseminated malignant melanoma.

Forty-seven patients with metastatic malignant melanoma took part in a phase II trial of tauromustine (TCNU), a new chlorethylnitrosourea based on the endogenous amino acid taurine. TCNU was given orally at a dosage of 130 mg/m2 every fifth week. No patient had previously received cytotoxic therapy. Among 37 evaluable patients, 26 patients experienced progressive disease including seven patients with early death, five showed no change, and six partial responses, yielding an objective response rate of 16%. Responses were limited to subcutaneous, lymph node, bone and lung metastases. Median time to progression was 26 weeks for responders. The treatment schedule was well tolerated with a median dose of 88% of the predicted dose given during all cycles. Dose-limiting toxicity was thrombocytopenia. It appears that TCNU is active in disseminated malignant melanoma with a response rate similar to other nitrosoureas.

Adolescent↗
PubMed1989

Histamine release from dispersed human intestinal mast cells. A method using biopsies from children and adults.

To study the human intestinal mast cell of children and adults, we combined a sensitive glassfibre-based histamine assay with the enzymatic and mechanical dispersion of surgical specimens or mucosal biopsies. The method yields between 1.2 x 10(3) to 4.6 x 10(3) mast cells/mg tissue constituting 1.2% to 5.3% of total cell count. The mast cell yield, however, depends on the intestinal tissue specimen used for dispersion. Aliquots containing 1500 mast cells per sample are sufficient for measuring significant amounts of histamine (greater than or equal to 0.15 ng histamine per sample), thus making it possible, to carry out approximately 75 tests for four mucosal biopsies of 10 mg each. The intestinal mast cell releases histamine in a dose-dependent manner on challenge with anti-IgE (6-600 U/ml), ionophore A23187 (0.25-1.0 microM), and Concanavalin A (0.7-25.0 micrograms/ml). The histamine release shows interindividual variation with a net histamine release between 0 to 2.5 ng/samples dependent on the secretatogue. In general, it is not necessary to passively sensitize the mast cells to obtain a sufficient histamine release response to anti-IgE challenge, indicating the presence of intact and functional cell-bound IgE. However, it is shown that four of 10 non-atopic intestinal mast cell samples could be passively sensitized with human plasma containing either mite- or grass-specific IgE without stripping off the IgE first. This indicates the presence of free and preserved Fc-receptors on the dispersed mast cells in some subjects. In addition, it is found that the phorbolester TPA increases the histamine release response to A23187 and turns anti-IgE non-responding mast cells into responding mast cells, but TPA alone at 2 to 16 ng/ml has no histamine releasing effect. In patients with anti-IgE responding mast cells no additional effect of TPA is seen. Finally, no substantial differences between mast cells of children and adults are demonstrated.

Biopsy↗
PubMed1989

Comparison of intestinal mast cell and basophil histamine release in children with food allergic reactions.

The in vitro histamine release response of human intestinal mast cells and basophils challenged with anti-IgE, Concanavalin A, ionophore A23187 and food extracts was compared with skin prick test, RAST analysis and open food challenge. It was not possible to perform food challenge in all patients; however, seven children underwent open food challenge and in five the clinical diagnosis of "true" food allergy was confirmed. The intestinal mast cells were pooled from enzymatically dispersed duodenal biopsies obtained by duodenoscopy from 15 selected children suspected of food allergy, and five age-matched controls. In nine of 10 patients classified as "food allergic" intestinal mast cells released histamine to various food extracts in a dose-dependent fashion. From the mast cells of the nine food-allergic patients compared with non-allergics, the anti-IgE mediated mast cell histamine release was increased. Additionally, at 1000 U/ml anti-IgE the mast cell histamine release was increased compared with their corresponding basophils. However, in non-allergic subjects the histamine release of basophils was increased compared with their corresponding mast cells. Histamine release from basophils was positively correlated to the test scores of the RAST analysis, skin prick test, and food challenge. No apparent correlation between tests scores obtained from histamine release of intestinal mast cell and the other tests was demonstrated, except in children with diarrhoea as only symptom. However, the study gives evidence that duodenal mast cells actually are sensitized with specific IgE and thus may play a pathophysiological role in food hypersensitivity. In addition, the study shows that the ability of different stimuli, including food extracts, to trigger basophil histamine release does not correlate with their potency to induce histamine release from mast cells.

Allergens↗
PubMed1989

[Complications during implantation of 3260 hip endoprostheses under spinal anesthesia].

There is a tendency to perform increasingly severe operations on patients of advanced age. Because geriatric patients are of greater risk when under anesthesia during operation, it is necessary to be aware of the possible anesthesia-related and operation-related complications. In a retrospective study the complication rate with regard to patients (age, multimorbidity), operation (e.g. number and duration of procedures) and anesthesia was analyzed. Of particular interest were the kind and degree of certain complications at a particular time. Directly following the induction of anesthesia and the second application of cement the complication rate depended on patient age and multimorbidity, but the intraoperative complication rate was closely related to the operation. Sensory spreading of spinal anesthesia was one of the anesthesiological factors leading to an increase in the complication rate. Cardiovascular complications occurred most frequently following the induction of spinal anesthesia (hypotension: 6.50%, tachycardias: 3.74%, bradycardias: 3.68%). The most serious circulatory complication--shock--however was primarily seen during surgery [1.80% (n = 59)]. Asystoles [0.27% (n = 9)] were only seen intraoperatively and after the second cement application. Pulmonary embolism [0.12% (n = 4)], respiratory arrest [0.09% (n = 3)] and exitus [0.64% (n = 21)] exclusively occurred following the second administration of cement. Geriatric patients are particularly at risk directly after induction of anesthesia and following application of the second cement. Thorough preoperative preparation (with regard to the cardiac and circulatory situation), spinal anesthesia of less than Th 6 and a rapid surgical procedure are necessary to reduce the morbidity and mortality.

Adult↗
PubMed1988

Inhibition of basophil histamine release by methotrexate.

Basophil leukocytes in whole blood from 4 healthy donors, 4 atopic patients, and 10 female patients operated for breast-cancer were preincubated from 1 to 20 hrs alone or in the presence of methotrexate (MTX) or MTX and folinic acid. After preincubation, the basophil leukocytes were challenged with anti-IgE, allergens or the calcium ionophore A23187 in the presence of 25 ng/ml TPA (12-o-tetradecanoyl-phorbol-13-acetate). A 9-hr preincubation with MTX produced significant inhibition of histamine release (greater than 20%) at 500-50 micrograms/ml. This effect increased up to 20 hrs of incubation, displaying maximal activity (100% inhibition) at 500 micrograms/ml, but even submicrogram concentrations (0.5 microgram/ml) produced significant inhibition. The addition of folinic acid did not alter the inhibition. It is concluded that MTX with or without the addition of folinic acid is a potent inhibitor of histamine release induced by anti-IgE, allergens, and A23187 combined with TPA. Like glucocorticoids the mechanism of action of MTX may be linked to arachidonate metabolism, but may interrupt earlier steps in prostaglandin synthesis.

Adult↗
PubMed1988

VM-26 (teniposide)-induced hypersensitivity and degranulation of basophils in children.

During a 7 year period, 16 episodes of VM-26 (teniposide) hypersensitivity occurred in our Department of Pediatrics. Eight of these (50%) were observed in neuroblastoma patients, of whom a total of 22 children had been treated with VM-26. The predominant signs were facial edema, flushing, urticaria, bronchospasm, tachycardia, and hypotension. All children with hypersensitivity recovered, but four of them were critically ill. No risk factors were found. In order to elucidate the mechanism of the hypersensitivity episode further, and to identify a possible allergen, histamine release from basophil leukocytes was performed by use of a glass microfiber method. Blood samples from nine cases reacting to VM-26, eight controls (children exposed to VM-26 without any hypersensitivity reactions), and 12 healthy children without previous exposure were challenged with VM-26 alone and with its vehicle, cremaphor. In all samples, it was found that VM-26 degranulated basophils, whereas no histamine release was seen after challenge with cremaphor. The reaction was dose-dependent, and not IgE-mediated, since IgE depletion of the cells did not abolish histamine release after VM-26 challenge.

Adolescent↗
PubMed1988

Passive sensitization of basophil leukocytes from non-atopic adult by plasma from allergic children.

Basophil leukocytes from a non-atopic donor, who responded well to anti-IgE, were depleted of their native membrane-bound IgE by acid treatment and passively sensitized with plasma containing either Phleum pratense-, Dermatophagoides pteronyssinus- or dog dander- specific IgE obtained from 18 allergic children. Histamine release was then performed on the passively sensitized cells and the results were compared with those of bronchial provocation test (BPT), allergen-specific serum IgE (RAST), skin prick test (SPT), and conventional histamine release test (HR). A high coincidence rate was found between BPT, RAST and histamine release after passive sensitization (HR-PS), but compared to HR, it was lower. This could be because several of the patients had non-responding basophils (i.e. no release after challenge with anti-IgE) in the conventional histamine release assay. The lower rate was not related to a lack of antigen-specific IgE, since after passive sensitization of basophils, anti-IgE and allergen provocation could induce release. It is concluded that plasma from allergic children with non-responding basophil leukocytes contain antigen-specific IgE capable of binding to Fc-receptors on the basophils of a non-atopic donor. In addition it was found that the plasma could change the cell reactivity (maximal histamine release) of the donor cells, since the amount of histamine released varied according to the plasma used for passive sensitization. The lack of histamine release response in some patients could be because their own membrane-bound IgE is unable to induce mediator release or, more likely, activation of one or more of the subcellular steps involved in the release is impaired.

Adolescent↗
PubMed1988

[Epinephrine in spinal anesthesia].

Isobaric bupivacaine for spinal anesthesia has frequently proved advantageous because of its long and safe analgesia, good motor blockade and low incidence of side-effects. Significant prolongation of analgesia is possible with an epinephrine concentration of as low as 1:200,000 added to bupivacain 0.5%, while optimal prolongation can be achieved by a concentration of 1:100,000. The addition of 1:50,000 epinephrine, however, does not induce any further enhancement. These results are contrary to those of Chambers and Scott, whose short durations of action were possibly due to relative overdosage of epinephrine with a paradoxical reduction of action. The latency period until complete blockade is achieved can be reduced by high epinephrine concentrations (beginning with 1:50,000), a fact which is possibly due to a direct, receptor-induced mechanism of epinephrine. The motor blockade of ankle and toe joints beginning from a concentration of 1:100,000 epinephrine is also prolonged significantly. With all epinephrine concentrations, the overall duration of analgesia could be prolonged significantly, in contrast to the overall duration of motor blockade. Only with free bupivacaine solution did motor and sensory function return at more or less the same time. The period between the beginning and the end of regression for both sensation and motor function was influenced only by the highest epinephrine concentration (1:50,000).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1988

[Disoprivan (Propofol) sedation during regional anesthesia. A pilot study].

In a preliminary pilot study, the effect of disoprivan for sedation during regional anesthesia was investigated. In 15 patients (ASA I or II), lumbar epidural anesthesia with bupivacaine 0.75% was performed at L 3/4. For premedication morphine or pethidine combined with scopolamine was given. After injection of the local anesthetic, a 30-min period was allowed for establishing the physiological side effects of epidural blockade, to present any further changes in circulatory and/or cardiac function. Disoprivan (1 mg/kg body weight) was injected i.v. followed by continuous disoprivan infusion. Three groups of 5 patients each were given 1, 1.5, or 2 mg/kg per hour disoprivan. Changes in heart rate, blood pressure, and respiratory rate were studied. Recovery time and personal assessment of sleep were registered. Side-effects of clinical relevance from the cardiovascular and pulmonary systems were also registered. A dose-dependent upper airway obstruction that could easily be managed by an oral or nasal airway was seen in 9 of 15 patients. Eight patients had postoperative nausea or vomiting; 9 complained of pain during the bolus injection that they could not remember postoperatively. All patients described their sleep as pleasant. Recovery time from sleep was between 1 and 12 min. All changes from normal values increased in percentage with increasing disoprivan dosage. Disoprivan (1 or 1.5 mg/kg per hour) seems to be excellent for sedation during regional anesthesia and is perhaps even superior to other available drugs.

Adult↗
PubMed1988

[Continuous sedation for regional anesthesia with propofol (Disoprivan) and midazolam (Dormicum). A comparative study].

UNLABELLED: Propofol was compared to midazolam with regard to its quality as a sedative in regional anesthesia. 81 patients undergoing varicose-vein stripping under epidural anesthesia were divided into two groups: 39 were given propofol and 42 were given midazolam. Both groups were then subdivided into 3 subgroups. 30 min after epidural block, a bolus of propofol 1 mg/kg or midazolam 0.03 mg/kg was given followed by infusion of equipotent solutions: propofol 1.0, 1.5, or 2.0 mg/kg/h or midazolam 0.03, 0.045, 0.06 mg/kg/h. Continuous registration of blood pressure, respiratory rate, and end-expiratory pCO2 was carried out and blood gas analysis was performed every 30 min. RESULTS: Clinically unimportant changes of circulatory and respiratory parameters were seen. Blood gas analyses showed hypercapnia greater than 50 mmHg in some patients. Brief apnea occurred after bolus propofol in 7.7% of cases and pain during injection in 66.6%. Restlessness: propofol 28.2%, midazolam 9.5%. Upper airway obstruction: propofol 30.8%, midazolam 57.1%. Recovery time after infusion ranged from 130 s with propofol to 26 min with midazolam. Postoperative evaluation included the following questions and responses: Sedation pleasant? propofol 97.5%, midazolam 100%. Sleep during surgery? propofol 94.8%, midazolam 83.5%. Prolonged tiredness? propofol 25.6%, midazolam 69%. Postoperative nausea? propofol 38.5%, midazolam 14.2%. Vomiting? propofol 17.9%, midazolam 11.9%. Our study showed that propofol is highly suitable as a sedative for regional anesthesia in spite of injection pain and frequent postoperative nausea. It is superior to midazolam because of the significantly shorter recovery time, providing improved control-lability and reduced posthypnotic sleep.

Anesthesia, Conduction↗
PubMed1988

[The monitoring of sympathetic activity following stellate ganglion block].

Variations in skin resistance are an indicator of a patient's sympathetic nerve activity. To record these variations, a mobile measuring system was developed. Even if this method is not yet used as a clinical routine, it could be helpful in studying the effects of nerve blocks in anesthesia. It seems to be advantageous for estimating the effectiveness of a block, the stress of the patient, and for recognizing very early reactions of a patient's sympathetic system. METHOD. An objective sign of a successful and sufficient block should be diminishing and finally the total lack of skin reaction amplitudes if the block is total. This was measured in a patient (male, 30 years old, nonsmoker, calm type) who suffered from a sudden loss of hearing on the left for four consecutive days when his left stellate ganglion was blocked. The effectiveness of the block was estimated from a two-channel measurement of skin reactions. On one channel the skin resistance of the blocked left side was recorded and on the other, unblocked skin areas of the right side were measured simultaneously. RESULTS. Although all four blocks were successful, which was evidenced by a Horner syndrome as well as elevated skin temperature 1-2 min after the injection of 7 ml bupivacaine (C6/C7), in all four cases residual sympathetic activity could be measured. In Fig. 1, the diminishing amplitudes of channel A as compared with channel B demonstrate this finding after the onset of a block at 2:03 p.m. An interpretation of skin reactions generated by a series of action potentials is given.(ABSTRACT TRUNCATED AT 250 WORDS)

Autonomic Nerve Block↗
PubMed1987

Stimulation of histamine synthesis from tumour cells by concanavalin A and A23187.

In the present study the amount of histamine synthesized by two experimental tumour cell lines, the Yoshida ascites sarcoma cells and SEWA cells, was measured after stimulation in vitro with the calcium ionophore A23187 and the plant lectin Concanavalin A (Con A). After 7 hrs of incubation with the two stimulators, histamine could be measured and the amount was still increasing up to 15 hrs of incubation with a maximal net histamine production of approximately 1.0 ng histamine per 10(6) tumour cells per ml sample. In addition, the tumour promoter 12-O-tetradecanoyl-phorbol-13-acetate (TPA) was found to enhance the synthesis of histamine in the presence of Con A or A23187, except in high concentrations, i.e. 50 ng/ml TPA, where an inhibitory effect was seen. TPA alone could not induce detectable histamine synthesis. In order to measure the histamine, the tumour cells were incubated in glass microfibre-based microtiter plates, which have been shown to bind histamine with high affinity and selectivity. The aim has been to develop a functional in vitro tumour assay which can detect histamine from tumour cells and which can be used to measure pharmacological interaction of the tumour cell function as well as histamine production from different tumour cell types.

Animals↗
PubMed1987

Impaired basophil histamine release from allergic patients.

A few patients (6-7%) with a verified type I allergic reaction do not respond with histamine release after challenge of their basophils with specific antigen (non-responding basophils from allergic patients). Sera from these non-responding patients were used for passive sensitization of responding cells from healthy controls. When these sensitized cells were challenged with specific antigen, histamine release was observed indicating that the non-responding allergic patients have circulating antigen-specific IgE capable of binding to Fc-receptors on the basophils. These findings suggest the possibility that non-responding basophils have impaired cell functions. We therefore examined the influence of enhanced IgE receptor stimulation on histamine release in non-responding basophils. This was made by stimulating protein kinase C activity by a phorbol ester (phorbol 12-myristate 13-acetate). When the non-responding cells were incubated with the phorbol ester and challenged with either anti-IgE or specific antigen, the cells released histamine. These findings support the hypothesis that the unresponsiveness of basophils in some allergic patients is associated with impaired IgE receptor complex activation or subcellular functioning and not with a lack of cell-bound IgE.

Asthma↗
PubMed1987

A new glass microfibre-based histamine analysis for allergy testing in children. Results compared with conventional leukocyte histamine release assay, skin prick test, bronchial provocation test and RAST.

A new microfibre method for allergy testing measuring histamine release from human basophil leukocytes is described. Samples of 50 microliter washed blood are challenged with the suspected allergens. Released histamine is bound to microfibres and measured by a spectrofluorometrical method after removal of interfering substances by washing. The microfibre method (HR-MM) was compared to the conventional histamine release assay using the Ficoll-Hypaque gradient method (HR-FH) in 19 allergic children tested with one of three allergens. In addition, a comparison was made between the microfibre method and in vivo provocation tests, i.e. skin prick test (SPT), bronchial provocation test (BPT) and allergen specific serum IgE (RAST). It was found that the same individuals responded with histamine release to the same allergens in both histamine release assays, and the dose-response curves were almost identical. A positive correlation was found between the in vivo and in vitro tests. Thus it is concluded that the new method can provide reproducible, analytically precise (at the nanogram level) histamine release results in pediatric cases where: a positive SPT does not correlate with case history; BPT may be considered too hazardous or inconvenient; confirmation of negative or inconclusive SPT or RAST is needed. In contrast to other histamine release assays it is a convenient diagnostic tool in children since only small amounts of blood are needed and at least 96 tests can be carried out in 2 1/2 h.

Asthma↗