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W Krumholz

Publications and source records attributed to W Krumholz.

At least 19 recordsLinked to original sources

[Variations of pain in the treatment of one classical acupuncture-point versus one point of Yamamoto's new scalp acupuncture].

INTRODUCTION: In an experimental design the pain reduction effect of acupuncture is studied and compared to the treatment of a classical acupuncture point and a point of the Yamamoto New Scalp Acupuncture (YNSA). METHODS: Experimental pain stimuli (32 per test person) were set in 42 test persons at the upper calcaneus edge and pain reduction was checked intra-individually by using the following variations of treatment: Acupuncture YNSA basis-point D, Acupuncture at the classical point Xiao Chang Shu = Bl 27, Acupuncture at a placebo point of the head, Acupuncture at a placebo point of the gluteal region. RESULTS: Evaluation of the data as well as a statistical investigation using a bi-factoral variance analysis with repeated measurements of 2 respectively 1 factor yielded following results: There are highly significant differences concerning pain reduction through the stimulation of the YNSA basis-point D and the acupuncture at the classical point Bl 27 (p < 0,0007). There are also highly significant differences concerning the verum and the placebo treatment (p < 0,00006). Further hypothesis of controlling the experimental design were tested. CONCLUSIONS: On the whole, the investigation shows that there is a marked difference between the verum and placebo treatment as well as a difference between the acupuncture of the YNSA basis-point D and the classical acupuncture point Xiao Chang Shu (Bl 27) with regard to pain reduction induced by experimental stimuli at the calcaneus. These differences are significant.

Acupuncture Analgesia↗

[The influence of various adjuvant drugs used in intensive care on monocyte chemotaxis].

OBJECTIVE: Monocytes play an important part in all phases of both humoral and cell-mediated immune responses. In our study, we examined the influence of various drugs used in intensive care (omeprazole, ranitidine, potassium canrenoate, furosemide, clonidine, verapamil, and metamizole) on monocyte chemotaxis in vitro. The 0,1 fold, 1 fold, and 10 fold concentrations, which are detectable in serum after a clinically efficacious bolus injection of the respective drug, were tested. METHODS: Using centrifugation, mononuclear cells were isolated from venous blood samples obtained from 10 healthy volunteers. Monocyte chemotaxis was determined by means of a microchemotaxis chamber. N-formyl-methionylleucylphenylalanine served as chemoattractant. RESULTS: Omeprazole, ranitidine, and potassium canrenoate did not influence monocyte chemotaxis. While the 10 fold concentrations of the clinically efficacious serum concentrations of furosemide and verapamil caused a significant inhibition, the 10 fold concentrations of the clinically efficacious serum concentrations of clonidine and metamizole significantly stimulated monocyte motility. CONCLUSION: Clinically relevant concentrations of the drugs tested did not alter monocyte chemotaxis in vitro. However, 10 fold concentrations of the clinically efficacious serum concentrations, which might occur in vivo due to drug interaction, cumulation, altered elimination, or accidental overdose, caused an inhibition (furosemide, verapamil) or a stimulation (clonidine, metamizole). An in vitro investigation does never permit to jump to clinical conclusions. However, our study gives impulses to conduct intensive care examinations concerning the influence of drugs on monocyte functions particularly since these cells are of great prognostical importance regarding sepsis.

Adjuvants, Anesthesia↗

The influence of intravenous anaesthetics on the activity of enzymes released from polymorphonuclear leucocytes in vitro.

BACKGROUND AND OBJECTIVE: Polymorphonuclear leucocytes make a decisive contribution to defence against bacterial infections. In particular, the effects of anaesthetics on non-oxidative bactericidal mechanisms have previously only been superficially examined. Although the influence of anaesthetic agents on oxidative bactericidal activity has been thoroughly examined, our study concentrated on the effect on non-oxidative processes, which appears to have been a neglected field of research. METHODS: The effects of methohexital, etomidate, ketamine, fentanyl and morphine on the activity of lysozyme and beta-glucuronidase released from polymorphonuclear leucocytes have been studied in vitro. The activity of lysozyme was determined by recording the changes in the turbidity of a suspension of micrococcus lysodeicticus caused by the enzymatic action of lysozyme. beta-glucuronidase activity was photometrically measured by the enzymatic cleavage of phenolphthalein glucuronic acid. RESULTS: High concentrations of methohexital inhibited lysozyme activity; however, etomidate and morphine caused an increase of beta-glucuronidase activity in therapeutic plasma concentrations. While there was no effect of etomidate on lysozyme activity, all concentrations tested significantly stimulated beta-glucuronidase activity. This result was unexpected because intravenous anaesthetics have previously shown a tendency to suppress polymorphonuclear leucocyte functions. Whereas the inhibition of lysozyme activity by the high concentration of methohexital was no surprise, the increase of beta-glucuronidase activity caused by etomidate, ketamine, fentanyl and morphine was quite unexpected. CONCLUSIONS: At present, the underlying mechanism for the increase of beta-glucuronidase activity caused by etomidate, ketamine, fentanyl and morphine is unknown. The fact that there was no influence of these agents on lysozyme activity possibly suggests that the anaesthetic agents have different effects on azurophilic and specific granules. Since in vitro investigations have their limitations, it is too early to draw practical consequences from our study. Moreover, at present it is unclear whether an increase of beta-glucuronidase activity in vivo is an advantage or not. In any case, we think it advisable to perform further investigations on the influence of anaesthetic agents on oxygen-independent bactericidal mechanisms.

Anesthetics, Intravenous↗

[Transmissible spongiform encephalopathies--anesthesiologic and intensive care management].

The transmissible spongiform encephalopathies (TSE) are known to affect humans and various animals. The bovine spongiform encephalopathy (BSE) and the human Creutzfeldt-Jacob disease (CJD) are among the most notable degenerative disorders caused by prions. Considering the BSE epidemic and the description of a new variant of Creutzfeldt-Jacob disease (nvCJD), which is probably related to bovine spongiform encephalopathy, TSE have recently gained a lot of public attention. Although the causative factors (prions, viruses) are still under discussion, none of the present concepts are explanatory for all aspects of the human CJD. CJD may present as a sporadic, genetic, or infectious illness and there is now considerable concern that bovine prions may have been passed to humans. To exclude transmission of CJD via medical products and instruments, the effectiveness of cleaning, disinfection and sterilization procedures must be firmly established. This manuscript presents an overview to anaesthesiology and intensive care medicine of recommended inactivation procedures and assessed these procedures in the light of the inactivation of prions.

Anesthesia↗

[The effect of midazolam and flunitrazepam on the liberation of lysozyme and beta-glucuronidase from neutrophil granulocytes in vitro].

OBJECTIVE: Polymorphonuclear neutrophile leucocytes (PMNL) play an important role in the defence against bacterial infections. It is known that some anaesthetics are able to disturb PMNL functions. We examined the influence of midazolam and flunitrazepam on the activity of the bactericidal enzymes lysozyme and beta-glucuronidase released from PMNL in vitro. METHODS: As described before [4], PMNL were isolated from venous blood samples obtained from 10 healthy male volunteers. PMNL stimulation and measurement of lysozyme and beta-glucuronidase activities were conducted according to the description by Metcalf et al. [5]. The BIOMED-system [8] was used for statistical evaluation. RESULTS: Neither midazolam nor flunitrazepam caused any statistically important alteration of lysozyme activity. However, clinically relevant concentrations of both benzodiazepines significantly enhanced beta-glucuronidase activity. The additives of flunitrazepam did not play any role. CONCLUSION: Surprisingly enough, midazolam and flunitrazepam increased the activity of beta-glucuronidase released from PMNL in vitro. At present, this result can neither be explained nor can its importance be estimated. On the other hand, the benzodiazepines did not relevantly influence lysozyme activity.

Anesthetics, Intravenous↗

[Effect of migraine medications on monocyte chemotaxis] .

Monocytes play an important role in humoral as well as in cell-mediated immunity. In the present study, the influences of the anti-migraine preparations metoprolol, propranolol, metoclopramide, acetylsalicylic acid, dihydro-ergotamine and sumatriptan on monocyte chemotaxis were examined in vitro. First, mononuclear cells were isolated by centrifugation from venous blood samples obtained from 10 healthy male volunteers. Chemotaxis was determined using a microchemotaxis chamber. While metoprolol, metoclopramide, dihydroergotamine and sumatriptan did not influence monocyte chemotaxis, high doses of propranolol and acetylsalicylic acid caused a significant (p < or = 0.001) inhibition of this important cellular function. Therefore, it is quite possible that both drugs produce adverse immunological effects in vivo in cases of high dosage or obstruction of elimination.

Adult↗

The influence of several intravenous anaesthetics on the chemotaxis of human monocytes in vitro.

Monocytes play a very important part in humoral as well as in cell-mediated immunity. At present, however, the knowledge of the influence of anaesthetic agents on the functions of monocytes is limited. In the present study, the effects of thiopentone, methohexitone, ketamine, midazolam, droperidol, propofol, etomidate, and fentanyl on monocyte chemotaxis were examined in vitro using a 48-well microchemotaxis chamber. Clinically relevant concentrations of ketamine, midazolam, and droperidol significantly (P < or = 0.05) inhibited chemotaxis. For that reason, it is possible that these anaesthetics impair the immunological system in vivo. This possibility should be further examined.

Anesthetics, Intravenous↗

Effects of i.v. anaesthetic agents on the chemotaxis of eosinophils in vitro.

Polymorphonuclear eosinophilic leucocytes (PME) participate in wound healing processes, the inflammatory response, bronchial asthma, allergies and defence against invading parasites. We have examined the effects of thiopental, methohexital, propofol, etomidate and ketamine on PME chemotaxis in vitro. PME were isolated from venous blood samples of 10 healthy volunteers using multi-stage Percoll gradient centrifugation. Eosinophilic chemotaxis was determined using a 48-well microchemotaxis chamber. Thiopental 150 micrograms ml-1 and etomidate 0.32 microgram ml-1 caused significant (P < or = 0.05) inhibition of PME chemotaxis. We conclude that thiopental and etomidate may have an adverse influence on wound healing processes and parasitic diseases. Further studies are recommended.

Analgesics↗

Inhibition of phagocytosis and killing of bacteria by anaesthetic agents in vitro.

Polymorphonuclear leucocytes (PMNL) are an essential contribution to protection from bacterial infection. We have examined the effects of thiopentone, etomidate, ketamine and flunitrazepam on phagocytosis and killing of Staphylococcus aureus and Escherichia coli by PMNL in vitro with fluorescence microscopy. All anaesthetic agents significantly inhibited both phagocytosis and bactericidal activity. The additives in the commercial preparations may have contributed to the suppression.

Adult↗

The effects of midazolam, droperidol, fentanyl, and alfentanil on phagocytosis and killing of bacteria by polymorphonuclear leukocytes in vitro.

Polymorphonuclear leukocytes (PMNL) make an outstanding contribution to the defence against invading bacteria. We studied the effects of midazolam, droperidol, fentanyl, and alfentanil on phagocytosis and killing of Staphylococcus aureus and Escherichia coli by PMNL in vitro. Using a method described by Eggleton et al., PMNL were isolated from venous blood samples obtained from ten volunteers. The fluorescence microscopic method mentioned by Bellinati-Pires et al. was used to examine phagocytosis and killing. Whereas both midazolam and droperidol caused a significant inhibition of phagocytosis as well as bactericidal activity, fentanyl and alfentanil did not influence these PMNL functions. In order to find out whether midazolam and droperidol are able to intensify perioperative bacterial infections in vivo as well, additional clinical studies should be conducted.

Adult↗

The effects of thiopentone, etomidate, ketamine and midazolam on several bactericidal functions of polymorphonuclear leucocytes in vitro.

Polymorphonuclear leucocytes (PMNL) are an essential component of the defence system against invading bacteria. There is evidence that some anaesthetics are able to suppress PMNL functions, promoting, perhaps, perioperative infection. We studied the effects of thiopentone, etomidate, ketamine, and midazolam on the generation of bactericidal agents (superoxide anion, hydrogen peroxide, and myeloperoxidase) by PMNL in vitro. Thiopentone inhibited superoxide anion (P < or = 0.01) as well as hydrogen peroxide production (P < or = 0.001). However, there was no statistically significant effect on myeloperoxidase release. Neither etomidate nor ketamine influenced the PMNL functions tested to any extent. Midazolam suppressed superoxide anion generation (P < or = 0.01) but only if a concentration far beyond clinical relevance was used.

Adult↗

Propofol inhibits phagocytosis and killing of Staphylococcus aureus and Escherichia coli by polymorphonuclear leukocytes in vitro.

Polymorphonuclear leukocytes (PMNL) are important components of the immunological defence system which protects the human organism from invading bacteria. Using a fluorescence microscopic method, we examined the influence of propofol and its solvent intralipid on phagocytosis and killing of Staphylococcus aureus and Escherichia coli by PMNL in vitro. Propofol inhibited (P < or = 0.001) phagocytosis of Staphylococcus aureus as well as Escherichia coli. Killing of Staphylococcus aureus (P < or = 0.001) and of Escherichia coli (P < or = 0.01) was suppressed. Intralipid, by itself, impaired phagocytosis of Escherichia coli (P < or = 0.05). Apart from that, intralipid produced no relevant effects. Additional clinical studies regarding the influence of propofol on PMNL function are recommended.

Adult↗

The influence of intravenous anaesthetics on polymorphonuclear leukocyte function.

Polymorphonuclear leukocytes (PMNL) play a vital role in the defence against invading bacteria. It is known that some anaesthetics inhibit PMNL function and, thus, possibly enhance perioperative infection. We investigated the effect of methohexitone, flunitrazepam, and droperidol on three bactericidal PMNL functions, i.e., superoxide anion production, hydrogen peroxide generation, and activity of released myeloperoxidase, in vitro. Approved photometrical assays were used. Superoxide anion was measured by the reduction of cytochrome C, hydrogen peroxide by the horse radish peroxidase catalysed oxidation of phenol red, and myeloperoxidase by the turnover of 2,2'-azino-di(3-ethylbenzthiazoline) sulfonic acid. Methohexitone (P < or = 0.001) and flunitrazepam (P < or = 0.01) inhibited superoxide anion production, and methohexitone (P < or = 0.01) reduced hydrogen peroxide generation but only at concentrations beyond clinical relevance. Droperidol did not cause any alteration of the PMNL functions tested. Consequently, it seems unlikely that the usual doses of methohexitone, flunitrazepam, or droperidol promote bacterial infections in vivo by impairing the activity of myeloperoxidase or by inhibiting the generation of superoxide anion or hydrogen peroxide.

Adult↗

The influence of fentanyl and alfentanil on functions of human polymorphonuclear leukocytes in vitro.

Polymorphonuclear leukocytes (PMNL) play an important part in protecting against invading bacteria. It is known that some anaesthetics may impair PMNL functions, thus possibly promoting infection. We investigated the effect of fentanyl and alfentanil on superoxide anion production, hydrogen peroxide generation, and activity of released myeloperoxidase in vitro. However, the two opioids did not have any significant influence on the tested PMNL functions.

Adult↗

[Lymphocyte subpopulations in patients at risk of sepsis in a surgical intensive care unit].

Infection remains a major cause of morbidity and mortality in intensive care medicine. The increased susceptibility of the severely injured patient to sepsis and consecutive multiorgan failure has been attributed to abnormalities in cell-mediated immunity. The purpose of our study was to determine changes in the pattern of lymphocyte subpopulations in severely injured patients and to relate these changes to any development of sepsis and to outcome (indirect immunofluorescence with monoclonal antibodies). During 14 months we investigated 28 patients (ages 15-65 years) suffering from severe multisystem trauma (22 cases) or diffuse peritonitis (6 cases), 6 of whom (21.4%) developed sepsis and multiorgan failure; 4 of these 6 septic patients died. According to the clinical data, patients developed sepsis between the 3rd and 6th days after trauma. We therefore defined days 1-3 as the preseptic phase, days 3-6 as the phase of sepsis development, and days 4-10 as the phase of septic disease. In the preseptic phase there was no statistically significant difference in the pattern of the eight lymphocyte subpopulations measured between patients who later developed sepsis and those who did not. During the phase of sepsis development, however, the patients who did develop sepsis showed significantly reduced numbers of CD2-, CD8-, and CD20-positive cells (P = 0.0003; P = 0.009; P = 0.012). The number of helper cells (CD4) was also decreased, but the difference between the two groups failed to reach statistical significance (P = 0.08).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[The significance of the sampling site in the determination of plasma levels of local anesthetics using 0.75% bupivacaine as an example].

Knowledge of the actual concentrations of local anesthetic administered by various techniques is essential requisite when undesirable side effects and possible toxicity of a substance are to be evaluated. Therefore, numerous studies of plasma concentrations have been presented, which were carried out with the additional purpose of analyzing the kinetics of different local anesthetics with respect to limiting-value concentrations in the organism. Despite a sufficient degree of precision in the analysis of amide local anesthetics, it is uncertain whether the results of the different studies are comparable, because blood samples have been taken variously from peripheral veins, central veins or arteries. In the present study changes in bupivacaine concentrations were monitored by means of a standardized method consisting in simultaneous sampling of blood in peripheral veins, central veins and arteries. METHODS. Each of 12 patients undergoing orthopedic hip surgery received average 17 ml bupivacaine (0.75%) via peridural lumbar catheter. After the administration of bupivacaine, blood samples were taken simultaneously from peripheral veins, central veins and arteries at 1, 3, 5, 10, 15, 30, 45, 60, and 90 min after injection. Placement of an arterial cannula and central venous catheter was indicated in all patients (hip-joint revision arthroplasty). Quantitative analysis of bupivacaine concentration was carried out by means of high-pressure liquid chromatography (HPLC). All patients had given their informed consent. RESULTS. All patients showed a rapid increase in bupivacaine concentration in the central venous blood within the first few minutes after administration, the maximum being reached between 3 and 10 min after. A similar course was observed with arterial plasma concentrations; absolute values, however, were an average of 10-20% lower at 15 min following administration. Bupivacaine concentrations in peripheral veins rose more slowly and reached a maximum between 15 and 30 min. At 30 min after peridural application the concentration curves in blood from all three sites were similar. DISCUSSION. In earlier studies the influence of the site of blood sampling has often been underestimated. According to our results, central venous and arterial plasma concentrations correspond closely at all times following peridural application. The observed uniform differences in concentrations at the various sites of sampling can be explained by the fact that pulmonary uptake of local anesthetics causes the lower arterial levels. Especially in the early phase of resorption after administration of local anesthetics, the concentration in peripheral blood does not seem to be representative, because an equilibrium is not established between arterial and central venous blood until 30 min after administration at the earliest. In our opinion the peripheral venous concentrations are unreliable, particularly in the early phases, for the evaluation of unwanted effects or toxicity of local anesthetics, because the initial low values and the delayed increase in these could lead to a false sense of security.

Aged↗

Effects of thiopentone and etomidate on median nerve somatosensory evoked responses.

Somatosensory evoked potentials (SEP) after median nerve stimulation were recorded in 40 patients during infusion of either 15 mg/kg bw thiopentone or 1 mg/kg bw etomidate (n = 10) within 15 min and after 0.3 mg/kg bw etomidate (n = 20). Marked alterations of SEP waveforms and changes in latencies were observed in all patients. Central conduction time (CCT) was significantly correlated to plasma thiopentone concentration. Infusion of high doses of thiopentone and etomidate was followed by a complete loss of middle and long latency components. Amplitude of the primary cortical SEP N20 was found to be unchanged after thiopentone and to be increased after etomidate, indicating the synchronizing properties of this drug. A pronounced increase in SEP latencies and CCT and waveform alterations have to be considered during hypnotic drug administration in intensive care medicine and intraoperatively.

Adult↗