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C Madl

Publications and source records attributed to C Madl.

16 recordsLinked to original sources

Serial recording of sensory evoked potentials: a noninvasive prognostic indicator in fulminant liver failure.

Sensory evoked potentials are markedly changed in patients with fulminant liver failure. It is unknown, however, whether serial recordings of sensory evoked potentials provide useful prognostic informations for patient management in fulminant liver failure. Ninety recordings of bilateral median nerve-stimulated short- and long-latency sensory evoked potentials were performed in 25 patients with fulminant liver failure (9 patients spontaneously recovered and survived, 8 patients were referred to emergency liver transplantation and 8 patients died). In all nine survivors the cortical long-latency sensory evoked potential N70 peak was constantly detectable between 74 and 162 ms. In all eight patients who subsequently underwent liver transplantation and in seven of eight patients who died, loss of the N70 peak developed during the course of fulminant liver failure. In 4 of 15 patients who were selected for liver transplantation according to the King's College criteria, the N70 peak was constantly detectable. All four transplantation candidates spontaneously recovered and survived without transplantation. In contrast, eight patients never did fulfill the criteria for liver transplantation. Five of them with constantly detectable N70 peak recovered spontaneously. However, in the remaining three patients loss of the N70 peak developed, and they ultimately died. The probability of correct outcome prediction by sensory evoked potentials is superior to that based on clinical criteria alone (0.96 vs. 0.72). Therefore serial recording of sensory evoked potentials may help identify (a) a subgroup among liver transplantation candidates who may spontaneously recover without transplantation and (b) a subgroup of patients with severe brain dysfunction who should undergo early liver transplantation even though they do not fulfill King's College criteria.

Adolescent

Cognitive brain function in non-demented patients with low-grade and high-grade carotid artery stenosis.

Atherosclerotic stenosis of the carotid arteries decreases cerebral flow volume and perfusion, and may result in brain dysfunction. We studied the relationship between the degree of carotid artery stenosis and cognitive brain function in non-demented patients. Cognitive brain function was assessed in 76 patients with carotid artery stenosis (38 patients with low-grade stenosis of 50% or less, and 38 patients with high-grade stenosis of 75% or more) by recording of cognitive P300 auditory evoked potentials and trailmaking test. Results were compared to 70 age-matched healthy subjects. The P300 peak latency was prolonged in patients with high-grade carotid artery stenosis as compared to patients with low-grade stenosis (403 vs. 371 ms, P < 0.01, vertex; 400 vs. 370 ms, P < 0.01, frontal; means). Analysis of variance revealed that the degree of carotid artery stenosis is an independent predictor of prolonged P300 peak latency (P = 0.0001). P300 amplitude (12 vs. 15 microV, vertex; 13 vs. 15 microV, frontal, NS) and trailmaking test (60 vs. 54 s; NS) tended to be worse in the high-grade stenosis group. There was no difference in cognitive brain function between patients with low-grade stenosis and age-matched healthy subjects. Confirmed on sensitive cognitive P300 measurements, we conclude that (a) cognitive brain function is impaired in non-demented patients with high-grade carotid artery stenosis but unaffected in low-grade stenosis; and (b) cognitive brain dysfunction is directly related to the degree of carotid artery stenosis.

Aged

Early prediction of individual outcome after cardiopulmonary resuscitation.

Prediction of individual outcome after cardiopulmonary resuscitation is of major medical, ethical, and socioeconomic interest but uncertain. We studied the early predictive potency of evoked potential recording after cardiac arrest in 66 resuscitated patients who returned to spontaneous circulation but were unconscious and mechanically ventilated. Detailed long-latency and short-latency sensory evoked potentials were recorded and neurological evaluations were done 4-48 h after admission to intensive care. In all 17 patients with favourable outcome (cerebral performance categories 1 and 2) the cortical evoked potential N70 peak, a reliable measure of cortical function, was detected between 74 and 116 ms. In 49 patients with bad outcome (categories 4 and 5) the N70 peak was absent in 35 or found with a delay between 121 and 171 ms in 14 (p < 0.05 vs favourable outcome). Thus the predictive ability was 100% with cutoff of 118 ms. To confirm reproducibility and validity, repeated tracings, and linked-earlobe referenced techniques were done and gave similar results. Early recording of long-latency evoked potentials after cardiopulmonary resuscitation is highly predictive of outcome.

Adolescent

Energy metabolism in acute hepatic failure.

BACKGROUND: Conflicting data are available concerning energy metabolism in liver disease. Changes should be most pronounced in acute hepatic failure in which loss of 85% of liver cell mass is reported. Metabolic rate could be decreased due to impairment in liver mass but may also be increased as a result of systemic-mediator actions. To clarify this issue we studied energy metabolism in acute hepatic failure. METHODS: Energy metabolism was evaluated by indirect calorimetry in 12 patients with acute liver failure and 22 sex-, age-, and body size-matched healthy individuals. In controls and 5 patients, studies were performed in the postabsorptive state; the remaining 7 patients received glucose at a rate of 8 mumol/kg body weight.min to prevent hypoglycemia. RESULTS: Resting energy expenditure was increased in acute liver failure compared with healthy controls (5.1 +/- 0.14 kJ.min-1 x 1.73 m-2 vs. 3.97 +/- 0.08 kJ.min-1 x 1.73 m-2; mean +/- SEM; P < 0.001). Respiratory quotient and oxidation rates for major fuels were not different between the total patient-group and controls. In patients without glucose supply, energy derived from fat was higher and from carbohydrate lower than in healthy controls and patients with glucose supply. CONCLUSIONS: Energy expenditure is increased in acute liver failure. Altered substrate oxidation can be normalized by glucose supply.

Adult

Diagnosis of gallbladder perforation in acute acalculous cholecystitis in critically ill patients.

In the presence of ascites ultrasound is not appropriate to distinguish between gallbladder perforation and acute acalculous cholecystitis. However, the correct and early diagnosis of gallbladder perforation is important for the treatment and prognosis. We report 4 critically ill patients with ascites. All patients had evidence of gallbladder perforation by ultrasound and underwent cholecystectomy: 2 patients had gallbladder perforation, but 2 had acalculous cholecystitis without perforation. Markedly elevated serum alkaline phosphatase was the only discriminating finding indicating gallbladder perforation.

Adult

Detailed evaluation of evoked potentials in Wilson's disease.

Detailed evoked potentials (EPs) were studied in 52 patients (28.7 +/- 11.9 years) with Wilson's disease (WD). Various peak latencies, interpeak latencies and amplitudes of somatosensory, auditory brain-stem and visual EPs were significantly abnormal in the group of 28 neurologically symptomatic patients as compared to controls. Interhemisphere latency and amplitude differences tended to be increased without reaching significance, indicating a symmetrical rather than focal subclinical brain involvement. Selected conduction times of at least 1 EP modality were prolonged in all 4 patients with severe, in 16 of 18 with moderate, in 4 of 6 with mild, and in 4 of 24 patients without neurological symptoms. Auditory brain-stem and somatosensory EPs were more frequently prolonged than visual EPs (more abnormalities with check sizes of 13 than 54 min of arc). Cortical somatosensory EPs correlated well (P much less than 0.01) with either Fz or earlobe reference.

Adolescent

Evoked potentials in severe herpes simplex encephalitis.

Diagnostic and prognostic value of evoked potentials (EP) were studied in 5 patients with severe herpes simplex encephalitis (HSE). Latency of the third negative cortical N70 peak, elicited by median nerve stimulation, was prolonged in 3 survivors with Glasgow coma score of less than or equal to 6 (115 vs 71 ms in controls, p less than 0.05), but normal after improvement of the acute disease. N70 right to left interhemisphere difference was increased initially in the 4 survivors (26 vs 3 ms in controls, p less than 0.05) indicating focal brain involvement, a crucial finding in HSE. The first cortical N20 peak was preserved in all survivors even during deep coma where evaluation of brain function is difficult. Auditory brainstem EP were normal in all patients and useful to exclude brainstem death. In severe HSE, somatosensory long-latency EP are an effective monitor of the level of impaired consciousness and can detect brain focal signs. Short-latency N20 components may be predictive of the outcome.

Adolescent

Comparison of functional and structural brain disturbances in Wilson's disease.

We assessed the functional and structural brain disturbances in Wilson's disease (WD) by evoked potentials (EPs) and magnetic resonance imaging (MRI). All the 25 neurologically symptomatic and 44% of the 16 asymptomatic patients, assessed by both EPs (n = 48) and imaging (n = 41), had at least 1 abnormality of either prolonged EP conduction times, imaging-outlined presence of cerebral lesions, or brain atrophy. Our findings indicate that EPs and MRI are sensitive techniques for the evaluation of brain involvement in WD.

Adult

Evoked potentials in assessment and follow-up of patients with Wilson's disease.

Treatment of 9 patients with Wilson's disease was prospectively studied with evoked potentials and magnetic resonance imaging (MRI). Oral penicillamine therapy led to a decrease in auditory brainstem (ABP) and somatosensory (SEP) conduction times in 6 and 4 neurologically symptomatic patients, respectively. ABP and SEP were normal in 3 other symptom-free patients. MRI showed cerebral lesions in 4 of 7 patients. Quantified indices of brain atrophy were unaffected by treatment. ABP and SEP may reveal a reversible component of the disease that cannot be detected by MRI, and may be a more sensitive measure of treatment efficacy.

Administration, Oral

Improvement of brain function in hemodialysis patients treated with erythropoietin.

To evaluate the effects of recombinant human erythropoietin (rHuEPO) on brain function, 15 chronic hemodialysis patients were studied by event-related P300, stimulus-related evoked potentials, and trailmaking before (hematocrit 22.7%) and after rHuEPO (hematocrit 30.6%). P300 peak latency elicited by a tone discrimination paradigm improved (391 before vs. 366 ms after; Cz = vertex; P less than 0.01) confirming beneficial effects on cerebral cognitive processing. P300 amplitude (13.6 vs. 15.8 microV; P = 0.06) and trailmaking tended to improve (55 vs. 43 s). P300 measures were influenced by low hemoglobin levels before rHuEPO (P less than 0.01), suggesting that severe anemia may contribute to uremic brain dysfunction. Furthermore, decrease of stimulus-related auditory brainstem I-V interpeak latency (4.28 before vs. 4.17 ms after; P less than 0.05) and increase of somatosensory N20/P25 amplitude (4.8 vs. 7.0 microV; P less than 0.05) pointed to improvement of sensory pathways by mechanisms unrelated to cognition. Brain dysfunction in chronic hemodialysis patients may, beside other factors, in part be caused by severe anemia and can be improved by rHuEPO treatment.

Anemia

Improvement of hepatic encephalopathy treated with flumazenil.

The effects of the benzodiazepine antagonist flumazenil were studied in 20 episodes of hepatic encephalopathy (HE) in 17 patients with acute (n = 9) or chronic (n = 8) liver failure who had not responded to conventional therapy. Patients with a history of benzodiazepine intake were excluded. Changes in HE stage, in Glasgow coma scale, and in somatosensory evoked potentials were measured. In 12 of 20 episodes HE stage improved. The response to treatment occurred rapidly (within 3-60 min). In 8 of these 12 episodes HE worsened 0.5-4 h after treatment. In 5 of the 8 episodes that did not respond to flumazenil patients had clinical evidence of brain oedema. Flumazenil may be valuable in the treatment of HE in acute and chronic liver failure.

Acute Disease