Search PubMed⌕ Search

Biomedical subjects

J Biscoping

Publications and source records attributed to J Biscoping.

At least 55 records · Page 3Linked to original sources

Influence of dextran on the absorption of adrenaline-containing lignocaine solutions: a protective mechanism in local anaesthesia.

The effect of adding 6% dextran to a lignocaine solution containing adrenaline was studied in 27 neurosurgical patients during modified neuroleptanaesthesia. Before trepanation they received infiltration anaesthesia of the scalp at the site of the proposed operation. For a period of 1 h following injection plasma concentrations of adrenaline were measured by high pressure liquid chromatography and serum concentrations of lignocaine by gas chromatography. The addition of dextran caused a significant reduction in the absorption of both adrenaline and lignocaine from the injection site. It is concluded that the dextran adjuvant constitutes a protective mechanism against toxic systemic side effects in local anaesthesia using adrenaline-containing anaesthetic solutions. This effect is particularly significant in patients with pre-existing cardiovascular disease and when local anaesthetic solutions are used in combination with volatile anaesthetics.

Absorption↗

[Sedative-analgesic medication in intensive care patients needing ventilator treatment].

UNLABELLED: It was the aim of this study to compare two regimens for sedation and analgesia during ventilator treatment in intensive care patients. Special regard was given to endocrine stress response, neuro-monitoring, hemodynamic parameters and clinical practicability. METHODS: A total number of 16 patients of an operative ICU were randomly allocated to the following groups: (1) Fentanyl-group, approximately 0.2 mg/h fentanyl, 2.5 mg/h midazolam and 2 mg/h pancuronium in intermittent doses, (2) ketamine-group, about 50 mg/h ketamine and 2.5 mg/h midazolam by syringe pump, in addition 2 mg/h pancuronium. During a period of 2 days and in intervalls of 6 h, plasma levels of epinephrine and norepinephrine (by HPLC/ECD), ADH, ACTH and cortisol (by RIA), ketamine (by GC) and stress-metabolites (glucose, lactate, free glycerol) were determined. Hemodynamic parameters were investigated in intervalls of 12 h, EEG (Compressed Spectral Array, CSA) in intervalls of 24 h. In addition, routine laboratory data, vigilance and adaptation to the respirator were observed. RESULTS: Plasma levels of adrenaline, noradrenaline, dopamine, ADH, ACTH, cortisol and stress-metabolites were comparable in both groups. Levels of ADH, ACTH, cortisol and free glycerol did not leave the normal range. In three patients, in which epinephrine- or norepinephrine-infusions were necessary to improve cardiocirculatory stability, this treatment could be finished after beginning of the ketamine application. In both groups, CSA showed a dominant delta- und theta-activity according to the clinical aspects of sufficient sedation and analgesia. Hemodynamic parameters were comparable in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Plasma concentrations of lidocaine and prilocaine following infiltration anesthesia in otorhinolaryngologic surgery].

UNLABELLED: Infiltration anaesthesia is still relevant for the surgical treatment of patients in otorhinolaryngology. The injection of local anaesthetics in well vascularised areas constantly causes the danger of high plasma concentrations of local anaesthetics combined with undesirable side effects. In our study we tried to determine the development of plasma concentrations of local anaesthetics in patients scheduled for routine tonsillectomies and tympanoplasty. MATERIALS AND METHODS: In 45 patients the development of plasma concentrations was measured immediately after the injection at short intervals; the samples were obtained between 1 minute and 60 minutes after the first injection. Group 1: Lidocaine 0.5% with epinephrine (1:200,000) 15-20 ml for tonsillectomy (n = 18). Group 2: Lidocaine 0.5% with epinephrine (1:200,000) 8-15 ml for tympanoplasty (n = 15). Group 3: Prilocaine 1% with epinephrine (1:200,000) 8-15 ml for tympanoplasty (n = 15). For tactical reasons infiltration anaesthesia for the patients of group 2 was - in addition to general anaesthesia - applied by the otorhinolaryngologist, whereas the patients of groups 1 and 3 were operated exclusively under local anaesthesia. RESULTS: Within the first minute after the initial injection plasma concentrations of the local anesthetic increased close to toxic threshold levels that are associated with undesirable systemic side effects. In the patients of group 1, who underwent tonsillectomy, plasma concentrations of 4-7 micrograms/ml were found during the first minute. The highest average values always appeared within the first five minutes: group 1 2.07 micrograms/ml, group 2: 0.45 micrograms/ml, and group 3: 1.15 micrograms/ml. DISCUSSION: With infiltration anaesthesia in well vascularised areas it may happen that there are--mainly in the early stage--high plasma concentrations of the applied substances, although the total dose was below the known maximum. Despite careful technique (repeated aspiration test in two levels) at least partial intravascular injections are apparently not always avoidable according to the pharmacokinetic data. Our results demonstrate that in addition to a safe peripheral venous line and prophylactic oxygen therapy, intraoperative monitoring of blood pressure, heart rate, electrocardiogram and verbal patient monitoring is of advantage in this group of patients. In our opinion the "standby function" of an anaesthesiologist can avoid severe complications.

Adolescent↗

[Effect of dyshemoglobinemia (methemoglobinemia and carboxyhemoglobinemia) on accuracy of measurement in pulse oximetry in operations of long duration].

In two groups - eleven patients each - who underwent long lasting surgical procedures, arterial oxygen saturation was measured non-invasively (pulse oximeter) and invasively (CO-oximeter). In addition, total haemoglobin (THb), fractions of haemoglobin (metHb) and bloodgases were monitored. All patients of group I received an epidural anaesthesia via catheter with prilocaine combined with general anaesthesia. In group II a modified neurolept analgesia (balanced) was performed. As expepted we found a prilocaine-induced methaemoglobinaemia (metHb up to 11.6 Vol%) whereas in group II physiological values were not exceeded. Carboxyhaemoglobin up to 4 Vol% was found in the smokers of both groups, which decreased continuously - in contrast to metHb - during hyperoxic ventilation. Comparing the non-invasively and the invasively determined saturations no correlation (r = -0.002) was found in group I. However, a positive correlation (r = 0.652) was obtained in group II. After correction of SaO2 (pulse oximeter) using an adjusted formula a fair correlation (0.613) was found in group I, too. Using this equation for correction the correlation in group II increased to r = 0.824. Because of methodological facts (the pulse oximeter registers only desoxygenated haemoglobin) the arterial oxygen desaturation (O2Hb or fractional saturation) accompanying dyshaemoglobinaemia remains undetectable to the pulse oximeter. In the cases of known or expected dyshaemoglobinaemia pulse oximetry can yield only limited information; fractions of inactive haemoglobin should be measured by other means or accounted for by the given equation for correction (SaO2 corr. = SaO2 pulse oximeter - (COHb + metHb]. Pathophysiological effects of dyshaemoglobinaemia are discussed.

Abdomen↗

[Behavior of plasma concentrations of prilocaine following intravenous regional anesthesia and their relation to methemoglobinemia].

In a previous investigation we were able to demonstrate quite different methemoglobin levels after axillary plexus blockade on one side and intravenous regional anesthesia (IVRA) on the other using prilocaine (Fig. 1). At that time we tried to explain this observation by prolonged mobilization of the local anesthetic after tourniquet release, causing only minimal stress to the erythrocyte-related reduction system. In order to study prilocaine mobilization after tourniquet release in the upper limb following IVRA, prilocaine and methemoglobin concentrations were measured in 8 patients. All patients received 400 mg prilocaine; IVRA lasted 30 min in all cases. In each patient we inserted an intra-venous line via the cubital vein with its orifice in the region of the venous outflow of the blocked upper extremity (Fig. 2). Simultaneously, blood samples were taken for measurement of plasma prilocaine concentrations in the axillary region of the blocked limb and from the contralateral upper limb. Following tourniquet release, samples were collected at short intervals for 15 min; starting with the 15th min methemoglobin concentrations were also determined for up to 5 h. The results of the outflow and systemic prilocaine concentrations are presented in Figure 3. Remarkable differences in peak prilocaine concentrations (64 micrograms/ml vs 7.9 micrograms/ml after the 1st min) were found during the 3-h study period. The course of methemoglobin formation was similar to that in a group of patients we had studied previously (Fig. 4). Our findings confirm the assumption that the low and plateau-like methemoglobin formation following intravenous regional anesthesia of the arm is the result of delayed prilocaine release.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Conduction↗

[Effect of pancuronium bromide on the adherence of polymorphonuclear neutrophilic granulocytes in vitro].

Infection is still an important problem following surgery. Polymorphonuclear neutrophil granulocytes (PMN) play a vital role in host defenses against invading bacteria; thus, adverse effects on PMN caused by anesthetic agents are of general interest. In this study, we examined the influence of pancuronium bromide on PMN adherence in vitro. Heparinized venous blood samples were obtained from 18 healthy male adult donors. Each specimen was divided. One part was used to determine the adherence of untreated PMN, while pancuronium bromide was added to the other. Two concentrations (1.3 or 0.5 micrograms relaxant/ml blood) were tested. PMN adherence was studied using nylon fiber columns as described by MacGregor et al. Both concentrations of pancuronium bromide caused an inhibition of adherence, which was significant in the case of the higher dosage (p less than 0.05). There is a direct correlation between the intensity of PMN adherence and the extent of granulocyte delivery to sites of inflammation. Therefore, it seems possible that clinical concentrations of pancuronium bromide may be able to increase the risk of developing bacterial infections. Further studies concerning this problem should be conducted.

Adult↗

[The action of bupivacaine-HCl following supraclavicular plexus block in patients with chronic kidney insufficiency].

A reduced duration of activity of local anesthetic drugs in patients with chronic renal failure has been described by several authors. Because surgical duration is not always predictable and these patients must be classified as high-risk patients (ASA physical status III-IV), reduced effectiveness may be a significant problem in clinical practice. Various reasons have been discussed as possible explanations for this phenomenon such as: (1) uremia-induced changes in acid-base status of blood and tissue, (2) alterations in protein-binding; and (3) changes in hemodynamic parameters. However, we have not been able to find any severe changes in electrolyte or acid-base status in patients with chronic renal failure after adequate hemodialysis. We wondered, therefore, whether changes in tissue pH might be one cause of the shorter duration of action of anesthetic drugs. We also examined some other pharmacokinetic parameters after administration of the anesthetic drug in order to find differences in comparison to healthy patients. Supraclavicular brachial blockade (3 mg/kg bupivacaine 0.5% + 0.1 IU vasopressin/ml) was performed in 11 patients with chronic renal failure requiring hemodialysis who were admitted to the hospital for a shunt operation in the forearm. The control group consisted of 11 healthy patients who were admitted for minor hand surgery. Preoperative blood samples were taken for measurement of blood urea nitrogen, serum creatinine, serum electrolytes, lactate, hemoglobin and hematocrit, and an arterial blood gas duration of action was defined as the time to full recovery of sensitivity.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

[Tube wall herniation in an Ulmer system as a cause of an intraoperative ventilation disorder].

We report an intraoperative complication caused by nitrous oxide diffusion through the inner layer of a tube of the Ulmer breathing system, which has been developed for ventilation of small children and neonates (Fig. 2a). About 40 min after intubation and mechanical ventilation with oxygen, nitrous oxide, and halothane a sudden rise in PETCO2 was noticed (Fig. 1). Auscultation of both lungs revealed no pathological finding; suction through the endotracheal tube was possible with no indication of endotracheal tube herniation. After reconnection to the ventilator, PETCO2 values again increased. Thorough inspection of the tubes of the Ulmer breathing system revealed a herniation that nearly occluded the lumen (Fig. 2b). After changing the anesthetic system, the operation and anesthesia were continued uneventfully.

Child, Preschool↗

[Comparative study of circulatory and ECG-changes after supraclavicular plexus block with bupivacaine-HCl 0.5 per cent in patients with chronic kidney failure].

The systemic effects of local anesthetic drugs, especially bupivacaine, on myocardial conduction and the increase of cardiotoxicity by hypoxemia, acidosis, and hyperkalemia has been proven in numerous animal experiments. In our department, supraclavicular brachial block with bupivacaine is the method of choice for patients with chronic renal failure requiring operations of the upper limb. The question may be raised whether or not these patients with their concomitant disease--electrolyte and acid-base imbalances, uremic cardiomyopathy--are especially endangered by the use of this drug. Supraclavicular brachial blockade (3 mg/kg bupivacaine 0.5% + 0.1 IU vasopressin/ml) was performed in 10 patients with chronic renal failure requiring hemodialysis. The control group consisted of 10 healthy patients who were admitted for minor hand surgery. Preoperative blood samples were taken for measurements of blood urea nitrogen, serum creatinine, serum electrolytes, and arterial blood gas analysis. Long-term ECG monitoring begun 20 min before injection of the block and continued over a total of 200 min. Serum concentrations of bupivacaine were determined at 10, 20, 30, 60, 120, and 180 min after injection. Comparing the two groups, no severe changes in electrolytes or acid-base status could be found despite some statistical significances. Even though bupivacaine serum concentrations proved to be 3 times higher in the study group than in the control group, no changes in cardiac conduction could be registered. We conclude that bupivacaine is as safe in dialyzed patients with chronic renal failure with regard to possible changes in circulatory parameters and myocardial conduction as in healthy patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Chemical Analysis↗

[Change in the adhesiveness of polymorphonuclear neutrophilic granulocytes by the intravenous anesthetics midazolam and ketamine].

The influence of midazolam and ketamine on polymorphonuclear neutrophil granulocyte (PMN) adherence was investigated in vitro by using nylon fiber columns. Both a concentration of 1.0 microgram midazolam/ml blood and 0.2 microgram/ml caused a reduction of adherence. This decrease was significant (p less than 0.05) in the case of the higher dosage. The two concentrations of ketamine used (1.3 micrograms/ml resp. 0.5 microgram/ml) produced a significant reduction of adherence too. Thus both anesthetic agents are able to impair PMN function in vitro dose-dependently. This feature is possibly related to increased risk of postoperative bacterial infection. Further studies concerning this problem should be conducted.

Adolescent↗

[Anesthesia procedures and perioperative patient monitoring in chemonucleolysis].

Premedication with H1 and H2 blockers as well as cortisone to reduce or prevent allergic reactions should be an integral part of the overall treatment. The facilities for immediate treatment of anaphylactic reactions including cardiopulmonary resuscitation must be readily available. Our haemodynamic measurements allow us to give a negative answer to the question--so far not investigated in man--whether the use of chymopapain or of its fragments leads to constant cardiocirculatory effective reactions in the early phase. Our experiences collected so far favour catheter peridural anaesthesia as the method of choice in chemonucleolyses.

Anesthesia↗

[Changes in lymphocyte subpopulations in relation to anesthesia procedure].

44 patients undergoing comparable gynaecological operations received either halothane- modified neuroleptanaesthesia or a combination of epidural and NLA. Monoclonal antibodies were used to determine 8 different lymphocyte subpopulations in blood samples drawn before and after anaesthesia and on the first postoperative day. Cell populations were counted by fluorescent microscopy. Halothane anaesthesia produced both a depression of T-cells (72.67% preoperatively to 52.79% postoperatively) and of the helper/suppressor ratio (1.46 to 1.10); meanwhile activated T-cells increased from 2.33% to 6.83%. After neuroleptanaesthesia as well as after halothane the HLA-DR positive cells decreased (21.05% to 19.29%; 25.22% to 20.29%). The B-cell fraction was elevated from 2.33% to 6.83% following combined anaesthesia. The potential of the anaesthetics to produce subsequent alterations in host defense is discussed.

Adult↗

[H-H-H syndrome: a rare disease also relevant in anesthesiology].

We report on a 17-year-old boy with H-H-H-syndrome (hyperornithinaemia, hyperammonaemia, homocitrullinuresis), an inborn disorder of the urea cycle, who had to undergo osteo-synthesis of a fractured upper leg. Pathophysiological aspects of this rare syndrome as well as possible recommendations for the anaesthesiological management are discussed.

Adolescent↗

[Effect of glucose concentration in bupivacaine solutions on the distribution of local anesthetics in cerebrospinal fluid during spinal anesthesia].

In two groups (ten patients each) catheter spinal anesthesia was performed with 3.0 ml bupivacaine hyperbaric (5% and 8% glucose was added). With special reference to the early phase following intrathecal injection, local anesthetic concentrations were measured by gas chromatography. A control group received 3.0 ml of isobaric bupivacaine intrathecally. With increasing specific gravity of these solutions, the CSF concentration of the local anesthetic decreased, which is interpreted as a consequence of inhomogeneous intrathecal distribution.

Aged↗

[Hygienic relations and stability of drugs in peridural long-term infusion with implanted or external pumps].

Implantable devices (implanted pump/implanted catheter and port) are recommended for continuous epidural application of opiates or local anaesthetics in order to reduce hygienic problems during long term epidural medication. No signs of contamination could be found during bacteriologic culture of residual volumes of 30 patients treated with epidural drug delivery systems and of samples collected during an in vitro investigation (incubation of filled external pump systems at body temperature/storage of syringes with a premixed solution of opiate and local anaesthetic for repeated epidural bolus application). As demonstrated in a case report prophylactic antibiotic coverage prior to implantation may be necessary in patients with a preexisting susceptibility to infection. The concentrations of morphine (radioimmuno-assay) and of bupivacaine (gas-solid chromatography) within the reservoir were stable during clinical therapy as well as during the in vitro experiments.

Abscess↗