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F Asskali

Publications and source records attributed to F Asskali.

30 records · Page 2Linked to original sources

[Life-threatening lactic acidosis during total parenteral nutrition. Successful therapy with thiamine].

Two patients, 37 and 44 years old, respectively, developed severe metabolic acidosis after abdominal surgery which was followed by three weeks of total parenteral nutrition. Septicaemia, peritonitis or hypoxia were excluded as possible causes. Both patients had very high serum lactate concentrations (24.3 and 22.8 mmol/l, respectively). Conventional treatment with buffer agents was unsuccessful. Because vitamin B1 deficiency was suspected, two doses of 400 mg thiamine were administered. In both patients the extreme lactic acidosis disappeared immediately after the injections. Both patients were later discharged without any symptoms.

Acidosis, Lactic↗

[The metabolism of panthenol in patients with postoperative intestinal atony].

The aim of this study was the examination of the metabolism and mechanism of action of D-pantothenyl alcohol in patients with postoperative intestinal atony. Seven metabolically healthy patients were examined on the 4th day following colorectal surgery, before bowel activity had started. Increased urinary excretion of the vitamin pantothenic acid was noted following the intravenous application of 2 gm of D-pantothenyl alcohol. Ten to 30% of the administered dose D-pantothenyl alcohol is excreted in the urine as pantothenic acid within 24 h. Simultaneously, the urinary excretion of beta-alanine, a pantothenic acid component, is increased. D-pantothenyl alcohol was metabolized to pantothenic acid in all the patients examined. Pantothenic acid is a component of coenzyme A, a key substance in the intermediary pathway of metabolism. Coenzyme A plays a role in the synthesis of acetylcholine from choline (a co-enzyme of cholinacetylase). Peristalsis induced by D-pantothenyl alcohol may be due to the increased synthesis of coenzyme A and acetylcholine in the autonomic nerve plexus of the intestinal tract.

Gastrointestinal Motility↗

[The plasma histamine level during anesthesia induction using midazolam].

Midazolam has not yet been investigated for its possible properties as a histamine releaser. The aim of the following study was to ascertain whether histamine release follows the i.v. injection of midazolam. METHODS. Twenty patients between 18 and 58 years of age were split into two groups at random. Either 0.15 mg/kg midazolam or 0.15 ml/kg NaCl 0.9% were injected i.v. Venous blood was drawn 2 min before and 2, 5, and 10 min after each injection. The content of histamine in plasma was determined by HPLC. RESULTS. In the midazolam group, histamine levels decreased from 0.37 ng/ml to 0.29 ng/ml after 5 min (P less than 0.05). The kinetics typical of histamine release could not be observed in any of the patients. We observed a slight decrease in the blood pressure or tachycardia in 3 patients, but even in these cases there was no increase in histamine level. In the NaCl group, the histamine level decreased from 0.34 ng/ml to 0.23 ng/ml after 2 min (P less than 0.05). The hemodynamics of these patients remained unchanged. One patient had an abnormally high histamine level prior to the injection (2.33 ng/ml). CONCLUSION. Our results show that midazolam is not a histamine releaser. The relevance of 1 patient having a high baseline level of histamine remains unclear.

Adult↗

[Metabolic changes and infusion therapy in ileus].

The aim of the investigation was to determine the changes in intermediary metabolism that occur in cases of ileus, and to develop a concept for parenteral perioperative nutrition on a pathophysiological basis. Seventeen metabolically healthy patients, suffering from mechanical ileus, have been evaluated. Besides the nonspecific metabolic changes characteristic of the postaggressive metabolism (abnormalities in peripheral glucose utilization, gluconeogenesis, lipolysis, proteolysis) we were able to demonstrate elevated serum levels of albumin, lactate and arachidonic acid preoperatively in these patients. The plasma histamine levels lay within normal limits. In the immediate postoperative phase (i.e. from 1.-3. postoperative day) we found a marked reduction in the serum levels of glucoplastic amino acids (about 30%), albumin (40%), pre-albumin (80%) and cholesterol (50%). We therefore suggest that, apart from electrolyte solutions, patients with an ileus should receive fructose (1600 kcal/day) preoperatively and from the first postoperative day amino acids (1 g/kg of body weight) and human albumin (as required) should be administered in addition.

Amino Acids↗

[The pharmacokinetics of midazolam following intramuscular administration].

There have been conflicting reports on the pharmacokinetics of midazolam, administered i.m. The aims of this study were to determine the pharmacokinetic data of midazolam following different doses and to test whether a correlation exists between its plasma level and sedative effect. METHODS. Fifteen patients between the ages of 18 and 50 were divided into three groups for i.m. administration of midazolam 0.05 mg/kg (group 1), 0.1 mg/kg (group 2), or 0.15 mg/kg (group 3) i.m. Venous blood was drawn 6, 12, 18, 24, 30, 36, 42, 48, 54, 60 min, and 2, 3, 4, 6, 8 h after the injection. After the same times the sedative effect was estimated by the anesthetist (awake, sleeping but easy to wake, sleeping and difficult to wake, unconscious). The plasma midazolam levels were determined by gas chromatography. The following pharmacokinetic parameters were ascertained: Cmax (peak concentration), tmax (time to attain peak concentration), clearance, elimination half-life. RESULTS. The peak concentration is directly proportional to the dosage of midazolam and the relation between the two is linear. The median Cmax values were 35.3 ng/ml (group 1), 103 ng/ml (group 2) and 123.5 ng/ml (group 3). The duration of tmax was between 12 and 36 min (means = 27 min). There was no significant difference between the groups in clearance, tmax, or elimination half-life. A significant correlation was found between the plasma midazolam levels and the degree of sedation. However, we observed a considerable variability in the effect. CONCLUSION. A 95% confidence interval for the prediction of the peak concentration of midazolam after i.m. injection is stated. Midazolam should be administered at a dose of 0.05 mg/kg at the most, if unconsciousness after premedication is to be avoided.

Adult↗

[Free fatty acids in the serum in critical diseases: do they play a role in the protein binding of thyroid hormones?].

As a contribution to the question if the elevated concentrations of free fatty acids in sera of critically ill patients described in literature play a role in the decrease of thyroid hormone levels in these patients, serum levels of the important free fatty acids were measured in 31 patients of our intensive care unit in the course of their disease using gas chromatography. After admission to the ward, only palmitoleic acid was significantly increased compared with 174 control persons, arachidonic acid was not different from the controls, palmitic, stearic, linoleic and linolenic acid were significantly decreased. In the course of the disease, no relevant changes were observed. The 21 patients not surviving their disease showed significantly lowered levels of palmitic, stearic and linoleic acid before death compared with the surviving patients at the end of the observation period. The hypothetical role of single free fatty acids as inhibitors of the binding of thyroid hormones to their transport proteins must be questioned because of the results.

Adolescent↗

[Postaggression metabolism following laparotomy and thoracotomy].

The purpose of this investigation was to collect data concerning changes in carbohydrate and amino acid metabolism following different surgical operations (thoracotomies, laparotomies). Blood of 20 metabolically healthy adult surgical patients, who had to undergo elective surgery (lobectomies, pneumonectomies, colon resections) was examined preoperatively, immediately postoperatively and from 1.-4.postoperative day. The experimental data during the perioperative phase showed a similar pattern in both groups of patients: We found a significant elevation in the blood glucose level and there was also a rise in plasma cortisol and plasma free fatty acids levels. We found no significant changes of blood lactate, plasma insulin and branched chain amino acids. Simultaneously we found a drop in plasma albumin, pre-albumin and some glucoplastic amino acids (ALA, GLN, THR, PRO). It is concluded that major abdominal and thoracic surgery give rise to a nonspecific stress situation reflected in carbohydrate and amino acid metabolism with the following metabolic symptoms: Raised lipolysis and gluconeogenesis, disturbance of glucose utilisation and obvious peripheral insulin resistance. These perioperative metabolic effects show some similarities to the metabolic situation in diabetes mellitus type 2.

Abdominal Neoplasms↗

[Behavior of the histamine level in induction of anesthesia with propofol and methohexital].

In a study of the effect of intravenous anesthetics on plasma histamine levels, propofol and methohexital were administered to patients. Histamine determination was performed using an improved fluometric method specific for imidazole derivatives. As a primary step, the plasma histamine concentration was determined in 60 healthy, fasting probands and used as a comparative value. The mean value obtained from 60 examinations was 0.38 +/- 0.12 ng/ml, the median value was 0.37 ng/ml (Table 1). The next step consisted in determination of plasma histamine values in 20 patients 1 h following premedication with fentanyl. In this group, the mean value was 0.33 +/- 0.11 ng/ml, the median value 0.316 ng/ml (Table 2). In another 20 patients the plasma histamine concentration was determined 1 h following intramuscular injection of 1.4 microgram fentanyl +0.07 mg/kg droperidol (Thalamonal). In this group, the mean value was 0.373 +/- 0.11 ng/ml and the median value was 0.736 ng/ml. Subsequently, the effect of 2.5 mg/kg propofol (Disoprivan) or 1 mg/kg methohexital (Brevimytal) on plasma histamine levels was examined in a randomized, prospective study in 22 patients of ASA class I and II (Table 3, Fig. 2). Two minutes prior to injection of the test substances and 2, 4, 8, and 13 min following injection, plasma histamine levels, blood pressure, and heart rate were examined. In both groups, no changes in plasma histamine levels were observed during the period of examination. Comparison of the individual time columns within a group as well as intergroup comparisons revealed no statistically significant differences in either the t test or the Wilcoxon-Mann-Whitney U test.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[The pharmacokinetics of midazolam in various kinds of anesthesia].

Several authors reported a decrease in metabolism of drugs during inhalational anesthesia. In this study we investigated the influence of several kinds of anesthesia on the metabolism of midazolam. Methods. In 43 patients who underwent minor surgery, anesthesia was induced by injecting 0.2 mg fentanyl followed by 0.15 mg/kg midazolam. Anesthesia was maintained by either halothane/nitrous oxide (group 1), isoflurane/nitrous oxide (group 2), fentanyl/droperidol/nitrous oxide (group 3), or halothane/air/oxygen (group 4). Venous blood was drawn after 5, 15, 30, 60, 90, 120, 180, 240, 300 and 360 min. Using the two-compartment model we estimated distribution half-life (t1/2a), elimination half-life (t1/2el), clearance (Cl), and volumes of distribution (Vz = volume in elimination phase). Results. There were no significant differences of elimination parameters between the four groups. Elimination half-life ranged from 0.72 to 15.06 h. Cl ranged from 2.5 to 12.8 ml/min per kilogram. Four patients (= 9%) had a t1/2el of 7-15 h; in 16 cases we found secondary concentration peaks. There was no correlation between drowsiness in the postoperative period and midazolam concentration. Conclusion. Even if anesthesia should influence the metabolism of midazolam, for example by reducing liver blood flow, we did not find any difference between the four groups. In accordance with others, we found some patients with a half-life of up to 15 h, which might reflect the influence of the anesthesia itself.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Continuous Midazolam infusion for sedation of respirator patients].

UNLABELLED: Most intensive care (ICU) patients need pharmacological sedation during ventilatory support. The short-acting drug midazolam might be preferable to neuroleptic agents and opiates because of its anxiolytic and sedative properties. The dosage of a drug given in a continuous infusion is based upon knowledge of its clearance and of the function of concentration and effect. METHOD: A midazolam infusion (7.5 or 15 mg/h) was given to 16 patients receiving ventilatory support for 24 h. Clearance was estimated using the rule Cl = R/C (R = rate of infusion, C = concentration in steady state). To estimate the concentration of midazolam necessary for good sedation, the amount of supplementary injected neuroleptic during midazolam infusion was compared with that of the day before. Plasma cortisol and parameters of energy metabolism, electrolytes, and liver and kidney function were measured. RESULTS: Patients with disease of abdominal organs showed the lowest values for clearance (1.0-2.92 ml/min/kg). Some of the injured patients showed elevated values for clearance (3.0-21.36 ml/min/kg). Elimination half-life ranged from 1.5-50 h. Changes in intestinal perfusion or cardiac output might be responsible for the wide range. For good sedation, plasma midazolam concentrations had to be above 600 ng/ml. Plasma cortisol levels were not affected by midazolam, nor were metabolism, electrolytes, or liver and kidney function. CONCLUSION: Continuous infusion of midazolam is a useful way of sedation for ICU patients, but the wide range of clearance values must be considered.

Adult↗

Midazolam does not antagonize fentanyl-mediated analgesia in surgical patients.

STUDY OBJECTIVE: To determine whether midazolam possesses a clinically significant antianalgesic action in surgical patients. DESIGN: Randomized, controlled study. SETTING: Inpatient anesthesia at a university department of neurosurgery. PATIENTS: 2 groups of 10 patients each who were scheduled for supratentorial brain surgery, did not have elevated intracranial pressure, and were free from systemic disease. INTERVENTIONS: Patients underwent anesthesia induction with hexobarbital, succinylcholine, and pancuronium; anesthesia was maintained with injections of droperidol-fentanyl (Group 1) or with midazolam-fentanyl (Group 2) following a predetermined repetitive dosing schedule, such that fentanyl 0.1 mg was injected upon predominant increases in heart rate, whereas droperidol 2.5 mg or midazolam 2.5 mg was injected upon increases in blood pressure. MEASUREMENTS AND MAIN RESULTS: Duration of anesthesia and invasiveness of surgery were similar in both groups. The amount of fentanyl required was 0.55 +/- 0.18 mg/hr (mean +/- SD) in Group 1 and 0.53 +/- 0.17 mg/hr in Group 2. Injections of droperidol 7.5 +/- 3.4 mg/hr (Group 1) and midazolam 5.9 +/- 2.3 mg/hr (Group 2) were administered intraoperatively. This redosing regimen was associated with uninterrupted hemodynamic stability, indicating comparable and adequate anesthetic depth. Plasma concentrations of metabolites and hormones indicative of humoral stress activation did not differ between groups. CONCLUSION: Under these clinical conditions, the administration of midazolam, when compared with droperidol, was not associated with signs of any antagonistic or antianalgesic action toward fentanyl-mediated analgesia.

Adolescent↗