Biomedical subjects

P Elsass

Publications and source records attributed to P Elsass.

28 records · Page 2Linked to original sources

PubMed1982

A clinical neuropsychological study of the postoperative course after three types of anaesthesia.

In a double-blind study, 57 patients were anaesthetized with either Althesin, thiopentone, or fentanyl combined with diazepam for cystoscopies. One and a half and four hours after the administration of anaesthesia, the patients were investigated with an objective neuropsychological method, continuous Reaction Time, and with a subjective rating scale. Beecher's Mood Scale. One week later the patients answered a questionnaire about side-effects experienced during the days following anaesthesia. At the 1 1/2 h investigation, the patients were cerebrally affected, both subjectively and objectively. The CNS-dysfunction was different for the three anaesthetics. After administration of thiopentone, the patients experienced the highest degree of subjective effects but had the smallest reaction time prolongation. Fentanyl-diazepam gave the least subjective effects, but the highest degree of cerebral affection in the reaction time measurements. The effects of Althesin were intermediate. Four hours after anaesthesia, the reaction time prolongations had disappeared, except for Althesin, and only patients who had thiopentone registered subjective effects. The number of side-effects was greatest and most prolonged following thiopentone. About 25% of the patients reported that side-effects had persisted more than 1 day after anaesthesia.

Adult↗

PubMed1981

Number connection test and continuous reaction times in non-encephalopathic patients: a comparative study.

Number Connection Test (NCT) and Continuous Reaction Times (CRT) were determined in 94 hospitalized patients with no previous or actual cerebral dysfunction. By NCT, 47 patients used more than 30 s which is the upper normal limit. Of these, 5 used more than 50 s. Two patients exhibited a CRT exceeding the upper normal limit of 240 ms. Thus, accepting the upper limits quoted, one-half of the patients were falsely classified as encephalopathic by NCT, but only 2% by CRT. This indicates that the NCT is too unspecific to exclude encephalopathy and suggests that the CRT is a more valid measure in this respect.

Adult↗

PubMed1981

Effect of lithium on reaction time--a study of diurnal variations.

Continuous reaction time performance was measured in groups of normal controls, psychiatric controls and patients treated with lithium. The reaction times were slower for the patients treated with lithium compared to both groups of controls, but the performance was not impaired to the same degree as in patients with various forms of cerebral dysfunction. For all groups reaction times were slower in the morning than in the evening or at night. Slow reaction times at the first investigation in the groups of normal and psychiatric controls were positively correlated with larger variations in the 24 h course. However, this correlation could not be demonstrated for patients on lithium treatment, probably because these patients do not approach their limit of speed as often as other patients or controls.

Adolescent↗

PubMed1981

Continuous reaction time in patients with hepatic encephalopathy. A quantitative measure of changes in consciousness.

In 14 patients with encephalopathy due to cirrhosis of the liver levels of consciousness were assessed by clinical ratings and continuous reaction time measurements. The observations were compared with similar measurements made in patients with chronic brain syndrome, patients sedated with diazepam, and hospitalized controls. Patients with hepatic encephalopathy were characterized by having slower reaction times than patients from the other groups. Furthermore, the performance of several liver patients was decreasing during the test. This phenomenon was not seen in the other groups. The continuous reaction times in the liver patients were correlated with the clinical ratings, but the reaction times appeared to be more sensitive, since on several occasions this test became abnormal before the clinical rating. Patients dying within 3 months after the test had more abnormal reaction times than patients surviving this period, indicating a relation between this test and the severity of the liver disease.

Adolescent↗

PubMed1980

Anxiety and sedation during a stressful situation after single dose of diazepam versus N-desmethyldiazepam--a controlled trial.

Twenty milligram diazepam (DZ) was compared with 20 mg of its main metabolite N-desmethyldiazepam (NDDZ) as single dose, oral premedication in a genuine stressful situation. Fifty patients participated in the randomized, double-blind controlled study. Anxiety and sedation were measured the day before an operation and one hour after premedication, just before the operation. NDDZ was significantly less sedative while the degree of anxiety was rated equal in the two groups. The results may support the hypothesis that a competition between DZ and NDDZ can explain the shift in the effect profile of DZ during long term treatment.

Adult↗

PubMed1980

Kinetics and neuropsychologic effects of IV diazepam in the presence and absence of its active N-desmethyl metabolite in humans.

In 12 healthy volunteers the kinetics and neuropsychological actions of IV diazepam (DZ) (single dose) were studied with and without the presence of its main metabolite N-desmethyldiazepam (NDDZ). Both the maximal plasma concentration and the steepness of the alpha-slope were correlated with variations in the corresponding continuous reaction time (CRT). EEG profiles, CRT and clinical ratings for anxiety and sedation all showed significant changes between the situations with the metabolite present or absent, but no significant correlation could be found with the kinetic pattern of DZ in the two situations. Tolerance to NDDZ did not develop. The results indicate that the presence of the active metabolite changes the pharmacodynamic profile of the parent compound probably by an interaction at the receptor site between DZ and NDDZ. Changes in the spectrum of effects during long-term therapy with DZ may, therefore, partly be explained in this way.

Adolescent↗

PubMed1979

Lithium effects on time estimation and mood in manic-melancholic patients. A study of diurnal variations.

Behavioural measurements of time experience and phenomenological self-ratings of mood-variations (Beecher's Mood Scale) have been carried out at night and on the following morning in a group of lithium-treated patients, in a group of psychiatric patients not given lithium, and in an untreated group of healthy subjects. In all the groups investigated the internal "clock" was slower in the morning than in the night. The results indicated that the internal "clock" in lithium-treated patients was slower than in the two other groups, but only at night. Mood variations from night ot morning were observed in all three groups. The group of lithium-treated patients had fewer complaints as to self-report of mood-variations compared with the other groups.

Adolescent↗

PubMed1978

Encephalopathy in patients with cirrhosis of the liver. A neuropsychological study.

Neuropsychological tests and clinical ratings of the level of consciousness were performed in 30 patients with encephalopathy due to cirrhosis of the liver. Compared to the test norms for patients with diffuse cerebral lesions, the state of encephalopathy in patients with cirrhosis has a qualitatively different pattern of cerebral affection, since disturbances of attention were found independently of general intellectual function. Eight cirrhotic patients without portacaval anastomosis were matched in clinical rating with 8 patients with portacaval anastomosis. The course of cerebral affection after portacaval shunts showed defects characteristic of intellectual impairments in diffuse cerebral lesions, which were not found in the non-operated matched controls.

Adult↗

PubMed1976

Neuropsychologic effects of diazepam related to single dose kinetics and liver function.

The neurophysiologic and neuropsychologic effects and their relation to the kinetics of diazepam (DZ) were studied in 10 patients with impaired liver function of various degrees and in three normal subjects after 10 mg DZ i.v. The plasma concentration data were treated according to a two-compartment open model. Neurophysiologic effect measurements were obtained from galvanic skin response, continuous reaction times (CRT), heart rate, and averaged evoked potentials; neuropsychologic measurements were obtained from trail making A + B, hidden pattern, word fluency, and subtraction tests; in addition, clinical effects were rated by Beechers Mood Scale and Spielbergers Anxiety Scale. Except for trail making A and word fluency all tests discriminated well between the experimental conditions with or without diazepam. No difference from normal in the response to acute diazepam administration could be detected in patients with reduced liver function. A linear correlation between prolongation in CRT and DZ log plasma concentration was demonstrated in the entire, heterogenous patient material. In the clinical ratings only items of a predominantly sedative and autonomic significance responded to the diazepam injection, while predominantly anxiolytic items did not.

Diazepam↗

PubMed1976

Clinical and psychological effects of intravenous diazepam related to plasma levels. A controlled, double-blind, cross-over study in oral surgery involving local analgesia.

In a controlled, double-blind, cross-over study with diazepam (DZ) and placebo (PL) various clinical, psychological, and pharmacological parameters were studied in 33 patients having identical impacted third molars removed. The patients were admitted to the study consecutively and nonparametric statistics were used throughout the study for the evaluation (Wilcoxon's matched-pairs signed test). The following aspects were examined: Continous reaction times (CRT), rating scales (a.m. Beecher), blood pressure, pulse, plasma concentration of DZ and of N-desmethyldiazepam, visual changes, amnesia, adverse reactions, recalling of duration of surgery, orientation in time, phlebitis, and final evaluation performed by the patient. The operative conditions were found to be excellent, and only a few adverse effects were noticed. The patients expressed an overall enthusiasm about the sedation. In the rating scales only the predominantly sedative items were affected and not the anxiolytic ones. Neither the heart rate nor the systolic blood pressure were significantly changed; on the contrary, the DZ-group was less affected than the PL-group when maximum increases in the systolic blood pressure were compared in the two groups. The continuous reaction times were significantly correlated to the plasma concentrations of diazepam, especially 1 hour after sedation. The reported recurrence of initial clinical symptoms 6 hours after sedation due to the N-desmethyldiazepam could not be demonstrated in this study. The CRT has proved itself to be of great value in discriminating between different kinds of cerebral affections; the patients with DZ-intoxication showed significantly faster CRT 1 hour after injection than did patients suffering from well-documented cerebral disorders such as organic brain damage or hepatic encephalopathia.

Adolescent↗