Biomedical subjects

Peter Ott

Publications and source records attributed to Peter Ott.

40 records · Page 3Linked to original sources

PubMed2002

Syncope with ST-segment abnormalities resembling Brugada syndrome due to reversible myocardial ischemia.

This report describes a case of syncope with an initial ECG that showed ST-segment elevation in the right precordial leads suggestive of Brugada syndrome. Procainamide infusion induced a significant increase in the ST-segment abnormalities, further increasing the suspicion for this syndrome. Cardiac catheterization showed lesions in the proximal left anterior descending artery and distal right coronary artery. Following percutaneous coronary intervention at these sites, the ST-segment abnormalities resolved and a repeat procainamide challenge was negative. Electrophysiological study did not provoke any ventricular arrhythmias. Silent myocardial ischemia may result in ECG changes that resemble those seen in patients with Brugada syndrome.

Aged↗

PubMed2002

Cerebral microdialysis in patients with fulminant hepatic failure.

Fulminant hepatic failure (FHF) is often complicated by high intracranial pressure (ICP) and fatal brain damage. In this study, we determined if a rise in [glutamate]ec and [lactate]ec preceded surges of high ICP in patients with FHF (median age, 42; range, 20-55 years; 7 women; 3 men) by inserting a microdialysis catheter into the brain-cortex together with an ICP catheter. The microdialysis catheter was perfused with artificial cerebrospinal-fluid at a rate of 0.3 microL/min. Dialysate was collected approximately every 30 minutes or when ICP increased. A total of 352 microdialysis samples were collected during a median of 3 days and allowed for approximately 1,760 bedside analyses of the collected dialysate. In 5 patients that later developed surges of high ICP, the initial values of [glutamate]ec and [lactate]ec were 2 to 5 times higher compared with patients with normal ICP. [Glutamate]ec then tended to vanish with time in both groups of patients. An increase in [glutamate]ec did not precede high ICP in any of the cases. In contrast, [lactate]ec was high throughout the study in the high ICP group and increased further before surges of high ICP. We conclude that in patients with FHF, cerebral [glutamate]ec and [lactate]ec are elevated. However, the elevated [glutamate]ec is not correlated to high ICP. In contrast, elevations in [lactate]ec preceded surges of high ICP. In conclusion, accelerated glycolysis with lactate accumulation is implicated in vasodilatation and high ICP in patients with FHF. The data suggest that bedside cerebral microdialysis is a valuable tool in monitoring patients with FHF and severe hyperammonemia.

Adult↗

PubMed2002

The value of plasma acetaminophen half-life in antidote-treated acetaminophen overdosage.

BACKGROUND: A plasma acetaminophen (INN, paracetamol) half-life of more than 4 hours has been correlated with hepatotoxicity in acetaminophen overdosing not treated with an antidote. Acetaminophen half-life has not been studied in patients receiving the antidote N -acetylcysteine. METHODS: Prospectively, 112 patients with acetaminophen overdosage all treated with intravenous N -acetylcysteine were studied. A minimum of 2 plasma acetaminophen values >20 micromol/L were available for calculation of acetaminophen half-life, assuming first-order kinetics. RESULTS: Overall, the median acetaminophen half-life was 5.4 hours (range, 0.8-119.7 hours). Forty-eight patients with no or little hepatotoxicity (ALT <1000 U/L), 43 patients with hepatotoxicity without encephalopathy, and 21 patients with hepatotoxicity and encephalopathy had acetaminophen half-lives of 3.0 hours (range, 0.8-10.0 hours), 6.4 hours (range, 1.3-19.0 hours), and 18.4 hours (range, 4.6-119.7 hours), respectively (P <.001). An acetaminophen half-life >4 hours was observed in 71 patients, and 56 of those (79%) had hepatotoxicity (ALT >1000 U/L or coma). Thirty-three of 41 patients (81%) with an acetaminophen half-life <4 hours had no hepatotoxicity. A receiver operating characteristic curve analysis showed that an acetaminophen half-life of 5.5 hours provided better discrimination; hepatotoxicity was therefore present in 49 of 54 patients with an acetaminophen half-life >5.5 hours (positive predictive value, 91%) and in 15 of 58 patients with a half-life below this limit (negative predictive value, 74%) despite treatment with N -acetylcysteine. CONCLUSIONS: Acetaminophen half-life correlates well with the degree of liver damage in patients treated with the antidote N-acetylcysteine. Longer half-lives reflect a greater toxic effect on the liver.

Acetaminophen↗

PubMedDate not supplied

Cardiac resynchronization therapy: a new therapy for advanced congestive heart failure.

Despite medical therapy, many patients with advanced systolic dysfunction remain highly symptomatic. In these patients the presence of a left bundle branch block on electrocardiogram indicates significant dyssynchrony of ventricular contraction. Cardiac resynchronization, by means of biventricular pacing, results in important clinical benefits. Due to the risk for malignant ventricular arrhythmias, this technology is best combined with an implantable cardioverter defibrillator.

Bundle-Branch Block↗