Midlatency auditory evoked potentials do not allow the prediction of recovery from general anesthesia with isoflurane

PURPOSE: To investigate midlatency auditory evoked potentials (MLAEP) waveforms during recovery from anesthesia. The hypothesis was that MLAEP are sensitive variables to discriminate between states of consciousness and unconsciousness during emergence from anesthesia. METHODS: MLAEP were recorded in the awake state and during the wake-up phase from isoflurane anesthesia in 22 female patients undergoing ophthalmologic surgery. During emergence from anesthesia the changes in latency and amplitude of MLAEP components Na, Pa and Nb were compared with the awake level. The next day the patients were asked for explicit memory for the recovery period. RESULTS: In 72% of the patients the MLAEP waveforms were completely suppressed during isoflurane anesthesia. When the patients responded and opened their eyes spontaneously 38 +/- 12 min after anesthesia, the latencies of Na (18.3 +/- 1.2 vs 17.6 +/- 1.3; P = 0.013) and Nb (47.4 vs 7.1 vs 44.7 +/- 7.8; P = 0.048) remained prolonged compared with awake values. In contrast, the amplitudes NaPa and PaNb had regained baseline level. Nine patients had explicit memory for the immediate recovery period. However, there was no difference for any MLAEP component between patients with and without memory at any time. CONCLUSIONS: The persistent changes of MLAEP latency components Na and Nb indicated impaired auditory signal processing 38 min after isoflurane anesthesia. There was a marked intra- and inter-individual variability during reversal of the anesthetic induced MLAEP changes. This limits the prediction of recovery of consciousness in the individual patient during emergence from anesthesia.     

Preconceptional factors associated with very low birthweight delivery in East and West Berlin: a case control study

Background  

Very low birthweight, i.e. a birthweight < 1500 g, is among the strongest determinants of infant mortality and childhood morbidity. To develop primary prevention approaches to VLBW birth and its sequelae, information is needed on the causes of preterm birth, their personal and social antecedents, and on conditions associated with very low birthweight. Despite the growing body of evidence linking sociodemographic variables with preterm delivery, little is known as to how this may be extrapolated to the risk of very low birthweight.     

Endophthalmitis caused by Moraxella osloensis

PURPOSE: To report the clinical presentation, antibiotic sensitivities, and treatment outcomes of endophthalmitis caused by Moraxella osloensis. METHODS: Case series: retrospective review of the medical records of all patients treated for endophthalmitis at Bascom Palmer Eye Institute between 1 January 1991 and 31 December 2000. RESULTS: During the study interval, 757 eyes were treated for endophthalmitis. Moraxella osloensis was isolated from three eyes of two patients (3/757, or 0.39%). In all three eyes, the endophthalmitis was delayed-onset and bleb-associated; Moraxella osloensis was isolated on chocolate agar and 5% sheep's blood agar using a RapNH commercial Kit (by Remel) through an automated system (Vitek). Like most gram-negative organisms, Moraxella was sensitive to ceftazidime, ciprofloxacin, and the aminoglycosides. Although vision at presentation was poor, both patients regained baseline vision after treatment with pars plana vitrectomy and injection of intravitreal antibiotics. CONCLUSIONS: To our knowledge, this is the first report of endophthalmitis caused by Moraxella osloensis. Unlike most series of delayed-onset, bleb-associated endophthalmitis the visual prognosis following treatment for endophthalmitis caused by Moraxella osloensis appears to be generally favorable.     

Quantitative measurement of regional lung ventilation using 3He MRI.

A new strategy for a quantitative measurement of regional pulmonary ventilation using hyperpolarized helium-3 (3He) MRI has been developed. The method employs the build-up of the signal intensity after a variable number of (3)He breaths. A mathematical model of the signal dynamics is presented, from which the local ventilation, defined as the fraction of gas exchanged per breath within a given volume, is calculated. The model was used to create ventilation maps of coronal slices of guinea pig lungs. Ventilation values very close to 1 were found in the trachea and the major airways. In the lung parenchyma, regions adjacent to the hilum showed values of 0.6-0.8, whereas 0.2-0.4 was measured in peripheral regions. Monte Carlo simulations were used to investigate the accuracy of the method and its limitations. The simulations revealed that, at presently attainable signal-to-noise ratios, the ventilation parameter can be determined with a relative uncertainty of <5% over a wide range of values.     

Spontaneous or interferon-γ-induced T-cell infiltration, HLA-DR and ICAM-1 expression in genitoanal warts are associated with TH1 or mixed TH1/TH2 cytokine mRNA expression profiles

The purpose of the study was to investigate the cytokine gene expression patterns and immunohistochemical characteristics of genitoanal warts in order to obtain a clue as to the immunological mechanisms possibly relevant for wart regression or persistence. We analysed surgically removed warts from 11 patients, 2 of whom were immunosuppressed. Lesions of five of the nine otherwise healthy individuals were additionally treated with intralesional interferon-γ (IFNγ) prior to surgery. Invasion of CD4 ⁺ T cells into the papillomas and HLA-DR and ICAM-1 expression on keratinocytes were found in two otherwise healthy patients and were intensified by intralesional IFNγ in four of five patients. The mRNA expression patterns in seven of eight nonrecurrent warts were compatible with a predominant TH1 or mixed TH1/TH2 cytokine profile. In contrast, in recalcitrant warts of three patients (one healthy, two immunocompromised) histological signs of immunoreactivity and TH1-like cytokine mRNA expression were not detected. In recurrent warts of a renal transplant patient, IL-4 and IL-5 mRNA expression was repeatedly found suggesting a predominant TH2 response. In conclusion, immunoreactivity to genitoanal warts such as T-cell infiltration, HLA-DR and ICAM-1 expression was associated with a predominant TH1 or mixed TH1/ TH2 cytokine mRNA expression profile. Received: 5 August 1996     

Polymeric surfactant systems in the asymmetric hydrogenation of amino acid precursors with a rhodium complex

The synthesis of new types of soluble and insoluble amphiphilic systems is described, being polysoaps, crosslinked polysoaps, an amphiphilised ion exchanger, and ion exchangers loaded with ionic surfactants. It was possible to synthesise insoluble polymeric systems which nevertheless showed micellar properties. The polymers were tested as aids in the stereospecific hydrogenation of (Z)-methyl α-acetamidocinnamate to the methyl ester of N-acetylphenylalanine (R) by means of an optically active rhodium complex in water. With linear polysoaps the effect on the reaction was dependent on the structure of the soap molecules. The enantioselectivity of the reaction with monomeric surfactants in water was almost attained. Crosslinked polysoaps showed the same effects on the hydrogenation as linear polysoaps with an analogous structure. Macromolecular ion exchangers loaded with amphiphilic counterions gave in hydrogenation almost the same effect as these counterions give when they are not bound to an insoluble carrier. Enantioselectivities and reaction rates were usually slightly lower than with monomeric surfactants. However, there is an advantage in the separation of catalyst and product after reaction. It was shown that the rhodium-containing amphiphilic ion exchangers could be reused for up to 9 times.     

Efficacy of cumulative doses of salbutamol administered via Turbuhaler® or Diskhaler® in patients with reversible airway obstruction

The study aimed to estimate the relative dose potency of salbutamol inhaled via Turbuhaler® and Diskhaler®. The 24 adult patients participating had chronic reversible airway obstruction. The study was of a double-blind, double-dummy, crossover, randomized design. Five doses of salbutamol Turbuhaler, 50, 50. 100, 200, and 400 ng, were given on one study day at intervals of 30 min. On another study day, five doses of salbutaniol Diskhaler, 200,200,400,800, and 1600 ng, were given with the same interval. The treatment days were separated by a washout period of at least 24 h. The inhalation technique was standardized and supervised. Efficacy variables were recorded before and after each study dose. The primary efficacy variable was forced expiratory volume in 1 s (FEVi). When parallel and linear cumulative dose-response curves were statistically compared on a logarithmic scale, the dose potency of salbutamol Turbuhaler v.v salbutamol Diskhaler was 1.99 (95% confidence interval 1.52–2.54). This study indicates that only half the dose of salbutamol is required via Turbuhaler as via Diskhaler for the same bronchodilating effect.