PubMed Health⌕ Search

Biomedical subjects

E Pöppel

Publications and source records attributed to E Pöppel.

At least 19 recordsLinked to original sources
PubMed1992

Patient controlled analgesia for extracorporeal shock wave lithotripsy of gallstones.

Sixty patients undergoing shock wave lithotripsy of gallbladder stones (ESWL) were randomly assigned to receive alfentanil either by infusion controlled by the attending anesthesiologist (standard treatment group, n = 31) or by analgesia controlled by the patient (PCA group, n = 29). Patients using PCA were allowed to self-administer 0.25 mg of alfentanil i.v. every minute as required. Data collected during treatment included the total dose of drug required, transcutaneous pCO2 values, verbal pain and sedation scores, visual analogue scale (VAS) patient satisfaction scores, and the incidence of nausea or vomiting. PCA patients used less alfentanil than the standard treatment group (PCA group: 12.8 micrograms/kg; standard treatment group: 44.3 micrograms/kg; mean values, P = 0.0001), tolerated significantly higher pain intensities and self-administered the narcotic only to moderate levels of pain but not to pronounced analgesia. Standard treatment patients reported lower levels of pain, were more sedated (P less than 0.05) and showed significantly higher transcutaneous pCO2 values. There was a trend towards a lower incidence of nausea or vomiting in PCA patients without reaching statistical significance. No significant difference with regard to patient satisfaction with pain relief could be demonstrated. Self-administered alfentanil during ESWL of gallbladder stones provided adequate analgesia with minimal side effects and high patient satisfaction. ESWL may represent a new and useful indication for PCA.

Adult↗
PubMed1992

Influence of stress on the healing and relapse of duodenal ulcers. A prospective, multicenter trial of 2109 patients with recurrent duodenal ulceration treated with ranitidine. RUDER Study Group.

The influence of psychologic factors on the healing and relapse of duodenal ulcers under treatment with ranitidine was studied in a prospective, multicenter trial in 2109 patients with an endoscopically proven duodenal ulcer (DU) and a history of recurrent duodenal ulceration. All patient received ranitidine (300 mg daily), and, after healing, 1899 patients continued maintenance treatment (ranitidine, 150 mg daily) for 2 years. A physician's assessment of stress (stress or no stress) was made at every consultation. In the healing phase an overall classification of stress as absent, intermittent, or continuous was made, and in the maintenance phase patients were classified dichotomously as having stress (stress on at least half of the follow-up consultations) or no stress. In addition, at the start of the healing phase stress was measured by means of a standardized questionnaire. Continuous stress, as assessed by the physicians, was associated with a lower 14-day healing rate (35.7%) than intermittent or absent stress (42.4%; relative risk (RR) for delayed healing in patients with continuous stress, 1.19; 95% confidence interval (CI), 1.06-1.33; P < 0.02). Differences in the 14-day healing rate for patients with low and moderate stress scores (43.1%) compared with those with high and very high stress scores (37.9%) just failed to reach statistical significance (RR for patients with stress, 1.14; 95% CI, 0.998-1.29; P = 0.051). During the 1st year of maintenance treatment 18.3% of patients with stress, but 10.9% of patients without stress, had a DU relapse (RR of stress for DU relapse during the first year, 1.73; 95 CI, 1.44-2.09; P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Cooperative tapping: time control under different feedback conditions.

The same isochronous tone sequence was presented simultaneously to two mutually isolated subjects. In half the trials, accentuation in this sequence was accomplished by doubling the duration of the first and then of every fourth tone; in the other half, by doubling the frequency of those tones. The subjects' task was to follow the rhythm of the resulting four-tone patterns by finger tapping to tone onsets. There were four auditory feedback (FB) conditions: (1) no FB; (2) FB from the subject's own motor responses; (3) "alien" FB from the motor responses of the other pair member who, in turn, was listening to FB from his/her own tapping; (4) mutually "crossed" FB, where each pair member listened to FB from the tapping of the other. Tap onsets regularly preceded stimulus onsets. The observed order of the amount of this anticipation (from least to greatest) was: (1) own FB, (2) no FB, (3) alien FB, and (4) crossed FB. No mutual dynamic influence between simultaneously performing subjects was detected. Anticipation was more pronounced for sequences that were accentuated by frequency rather than by duration changes. The type of accent also influenced timing of intertap intervals in the rhythmic patterns. For the frequency accent, regular timing was produced, whereas for the durational accent, shortening of the second and lengthening of the fourth (the last) intertap interval were observed. The presence and source of feedback as well as the character of accentuation are therefore relevant factors in the timing of auditorally controlled rhythmic motor behavior.

Adult↗
PubMed1991

Finger tapping in musicians and nonmusicians.

Timing plays an important role in perceiving and performing music. Finger tapping has been successfully used for analyzing timing processes (Fraisse, 1966, Franĕk et al., 1987, 1988). The aim of this study is to determine differences between musically trained and untrained subjects in their ability to follow repetitive rhythmic tonal patterns by finger tapping. It has been found previously (Povel, 1981; Smith, 1983) that time estimation differs among musicians and nonmusicians under certain conditions. The results presented here show that motor timing revealed by tapping is more accurate in musicians than in nonmusicians.

Fingers↗
PubMed1991

Sensory information processing during general anaesthesia: effect of isoflurane on auditory evoked neuronal oscillations.

There is evidence from neuropsychological and psychophysical measurements that sensory information is processed in discrete time segments. The segmentation process may be described as neuronal oscillation at a frequency of 30-40 Hz. Stimulus-induced neuronal oscillations of this frequency are found in the middle latency range of the auditory evoked potential (AEP). We have studied the effect of different end-tidal concentrations of isoflurane on auditory evoked 30-40 Hz neuronal oscillations. We studied 13 patients undergoing intra-abdominal urological and gynaecological procedures. AEP were recorded in the awake state and during end-expiratory steady state isoflurane concentrations of 0.3, 0.6 and 1.2 vol%. These incremental doses of isoflurane caused a stepwise decrease in frequency of oscillations. The decrease in oscillation frequency and sometimes the disappearance of oscillatory components may be interpreted as suppression of sensory information processing. The measurement of auditory evoked neuronal oscillations in the AEP appears to be a promising tool to monitor both sensory information processing capacity and depth of anaesthesia.

Adult↗
PubMed1991

Sensorimotor synchronization: motor responses to regular auditory patterns.

Subjects (N = 32) were asked to synchronize a motor response with tones in auditory patterns. These patterns were created from six tones and six intertone intervals of equal duration. The pitch of the first tone differed from the others. It was found that subjects used three types of timing in their motor response: (1) the first intertone interval was prolonged and the second interval was shortened, (2) the second intertone interval was prolonged and the first interval was shortened, and/or (3) the first interval and the second interval were of approximately the same length. The prolongation of the fifth interval was observed during all three types of timing. The results are explained using the concept of suprasegmental control of timing, which explains a prolongation of intervals at critical control point of the patterns. The occurrence of three different strategies of timing is discussed in connection with similar principles in musical performance.

Acoustic Stimulation↗
PubMed1991

[Conscious and unconscious acoustic perception during general anesthesia].

The possibility of processing sensory information during general anesthesia and the ability to recall it postoperatively is of major ethical, medical and even theoretical importance. Auditory stimuli especially are perceived intraoperatively and remembered postoperatively. Neuropsychological experiments indicate that sensory information can be processed and recalled both at a conscious and at an unconscious level. Therefore, we have to distinguish between explicit and implicit memory. Explicit memory is characterized by an active and conscious recall of space- and time-related events, i.e., episodes in a person's life. In contrast, implicit memory recalls passively and unconsciously without being related to space and time, i.e., language and general knowledge. Experimental results from amnesic patients indicate that these two memory systems work independently from each other. Even when explicit memory is grossly impaired the function of the implicit memory may still be completely preserved. Various studies on intraoperative awareness show that explicit memory is widely eliminated during general anesthesia. The incidence of conscious awareness that can be actively recalled postoperatively is reported to be 1-3%. In contrast, the implicit memory function can be partially preserved. When implicit memory tasks or hypnosis are employed, traces of unconscious memory of intraoperative auditory information can be shown in 20-30% of the patients. These observations are of important clinical relevance, because the unconsciously recalled information about the intraoperative procedure may have a negative influence on the patient's postoperative recovery and well-being. So far it is still not known which anesthetics most reliably suppress auditory perception and conscious and unconscious memory during the intraoperative period. Therefore, future studies should focus on several different points. The anesthetic state should be defined exactly and the functional state of the auditory modality should be monitored when auditory information is presented to the patients. The recollection of intraoperative events should be investigated using implicit memory tests, because these are regarded as more sensitive than explicit memory tests.

Anesthesia, General↗
PubMed1990

Stimulus anticipation in following rhythmic acoustical patterns by tapping.

Subjects followed rhythmic acoustical sequences by finger-tapping. Tapping onset preceded stimulus onset by a value close to 30 ms. It is suggested that this temporal difference might correspond to one cycle of a hypothetical timing mechanism in the brain which has been observed with other experimental paradigms.

Auditory Perception↗
PubMed1990

Multistable states in intrahemispheric learning of a sensorimotor task.

We have obtained evidence from an intrahemispheric learning task using a choice-reaction-time paradigm that the acquisition of a sensorimotor skill can be discontinuous. Subjects had to react as fast as possible to either a visual or an auditory stimulus. In several successive sessions, reaction times improved markedly, however in a discontinuous way. Different levels of performance were characterized by discrete functional states, each state being associated with a particular temporal window. After sufficient learning, reactions were confined to the earlier of two such windows.

Acoustic Stimulation↗
PubMed1990

Analysis of oscillatory components in perioperative AEP-recordings: a nonparametric procedure for frequency measurement.

Auditory evoked potentials (AEPs) were recorded in 15 patients scheduled for minor gynecological procedures. The suppression of a middle latency oscillation about 40 Hz was observed during 2 minutes after injection of the anesthetic agent propofol. The decrease in oscillation frequency during anesthetic induction was evaluated with a fast Fourier transformation (FFT) and a rank-correlation procedure (RCP). With AEPs having a short epoch of 100 ms the frequency resolution of the RCP was better than the frequency resolution of the FFT. The rank-correlation function of the RCP indicates an initial drop of oscillation frequency from 44 Hz to 37 Hz during 1 minute after anesthetic induction. During the second minute after the infusion of propofol, the oscillation frequency decreases from 37 Hz to 19 Hz. It is suggested that the suppression of neuronal oscillations in the AEP represents a loss of sensory information processing. The measurement of middle latency oscillations in the AEP is proposed to be a promising indicator for the intraoperative stage of anesthesia.

Adult↗