Heart rate and heart rate variability changes in the intracarotid sodium amobarbital test.

PURPOSE: Changes in heart rate and heart rate variability have been found in prior studies performed during the intracarotid sodium amobarbital (ISA) test. However, these results are not entirely consistent with current models of differential cerebral involvement in the modulation of the heart. This study was designed to re-investigate this topic with a larger N than has heretofore been used. METHODS: The electrocardiogram was recorded during left and right ISAs in 73 subjects. Raw heart rate and heart rate variability were calculated. RESULTS: Raw heart rate increased during inactivation of either hemisphere, but more so for the right hemisphere. Heart rate variability changes consistent with decreasing parasympathetic tone also were found to occur during either ISA, but to a significant degree, only during right ISA. CONCLUSIONS: The right hemisphere appears to have a greater role in cerebral regulation of cardiac function, perhaps by virtue of the modification of parasympathetic effects.

Affective self-report during the intracarotid sodium amobarbital test: group differences.

Emotional reactions are sometimes observed during the intracarotid sodium amobarbital test. For instance, euphoric/indifference reactions can be seen during right hemisphere inactivation and catastrophic reactions may accompany left hemisphere inactivation. Less dramatic changes can also be detected in affective self-report during left and right hemisphere amobarbital tests, with more negative affect reported during left hemisphere inactivation and either neutral or mildly positive affective states reported during right hemisphere inactivation. The current study not only replicated this effect, but in addition, found significant group differences. The first group (right way) showed a pattern of affective self-report during left and right amobarbital tests entirely consistent with prior findings, while a second group (wrong way) showed results that behaved in a diametrically opposite fashion. A third group (no change) showed little, if any, difference in affective self-report during left and right amobarbital tests. The major factor distinguishing the wrong way group from the other two appeared to be an asymmetrical distribution of left and right temporal lobe lesions in the former group. In contrast, the factor differentiating the right way group from the no change group appeared to be the relative degree of left hemisphere inactivation during the left hemisphere amobarbital test. The results are discussed not only in terms of their impact on theories of cerebral lateralization for emotion, but also in terms of methodological issues in this field.

Response of human epileptic temporal lobe cortical blood flow to hyperventilation.

Bilateral long-term surface cortical cerebral blood flow (CBF) and electrocorticographic (ECoG) monitoring were performed in eight patients with complex partial seizures. In each patient, the epileptic temporal lobe was localized using ictal ECoG. Mean seizure interval (frequency-1) off anticonvulsant medication, a clinical measure of epileptogenicity, was 1.0 +/- 0.3 h (range: 0.4 to 2.5 h). During 13 interictal hyperventilation periods, 3.6 +/- 0.6 min in duration, the mean decrease in epileptic and nonepileptic temporal cortical CBF was 13.7 +/- 2.3 versus 6.4 +/- 1.9 ml/(100 g min) (t = 2.230, d.f. = 16, P < 0.05), representing 20.9% and 10.8% reduction from baseline CBF during hyperventilation, respectively. Seizure interval decreased (i.e. frequency increased) with increasing magnitude of seizure focus CBF reduction during hyperventilation. Seizure interval was significantly correlated with epileptic temporal lobe CBF decrease during hyperventilation (R = 0.763, d.f. = 5, P < 0.05). The data suggest that, compared to nonepileptic brain, epileptic temporal lobe is particularly prone to hypoperfusion during hyperventilation. Epileptogenicity is a function of this seizure focus susceptibility to ischemia. The finding of abnormal seizure focus autoregulation during hyperventilation has implication for epileptic focus localization with cerebral blood flow analysis.

Epileptic spasms in older children: persistence beyond infancy.

Although infantile spasms (IS) constitute a well-recognized epileptic syndrome, only recently did investigators propose that spasms be classified as a distinct seizure type, characterized by axial flexion/extension jerks in clusters. Five older children (aged 4.5-14.2 years) who underwent video-EEG monitoring in 1992 in our epilepsy program for intractable mixed seizure disorder (cryptogenic 1, symptomatic 4) demonstrated flexor and extensor spasms in clusters. Seizure onset was from birth to 1.33 years. All 5 had spasms during infancy that continued as the children aged. Ictal EEG during spasms showed a brief high-amplitude delta burst followed by diffuse background attenuation or diffuse background decrease with superimposed rhythmic beta or alpha activity. Multiple other seizure types were present. Interictal EEGs were markedly abnormal and demonstrated slowing, multifocal spikes, generalized slow spike-wave, and polyspike-wave. Two children with spasms were unsuccessfully treated with ACTH, and 3 underwent corpus callosotomy. We conclude that spasms occur in older children with intractable mixed seizure disorders and may persist beyond infancy.

Nursing implications of the intracarotid amobarbital procedure.

The intracarotid amobarbital procedure, by inactivation of each hemisphere, provides the opportunity to evaluate language and memory function of the individual considering epilepsy surgery. Careful explanation of this procedure, and its importance to the proposed surgery are vital to the patient's cooperation and performance during this examination. The neuroscience nurse has a significant role in the success of this procedure. Nursing interventions include patient education, monitoring for potential complications, providing comfort measures, and assisting in the management of any life-threatening complications which do develop. A relatively little-known procedure outside of comprehensive epilepsy centers, the IAP offers opportunities for nursing research. These queries include investigation of emotional reactions in relation to gender differences, cultural and educational factors which may effect stimulus selection (eg, bilingual patients) and patient performance.

Quantitative analysis of the EEG in the intracarotid amobarbital procedure. I. Amplitude analysis.

Thirty-seven subjects underwent bilateral internal carotid artery injections of amobarbital prior to surgery for intractable epilepsy. The electroencephalogram (EEG) of these patients was continuously monitored during these 74 procedures and was later subjected to quantitative analysis. Topographic mapping of these data suggested that the areas of inactivation were largely restricted to the anterior 2/3 of the hemisphere injected, corresponding to the vascular distributions of the anterior and middle cerebral arteries. Graphical representation of the data demonstrated that delta and theta band activity peaked in the first 2 min post injection and decreased gradually thereafter, becoming stable at around 12 min post injection. Examination of the alpha, beta 1, and beta 2 bands suggested that activity increased and decreased more gradually than that for delta and theta, with perhaps a longer latency. Although EEG changes were most prominent in the anterior 2/3 of the inactivated hemisphere, similar (though smaller) changes were also observed in both ipsilateral and contralateral zones thought to be outside of the vascular distribution of the internal carotid artery.

Immunodeficiency secondary to juvenile paracoccidioidomycosis: associated infections.

Four patients with acute paracoccidioidomycosis, hypoalbuminemia, ascites and associated infections are reported. They have been admitted to hospital 35 times, 4 of them due to active paracoccidioidomycosis, 14 to associated infections, 14 to ascites, edema and diarrhoea and 3 to herniorrhaphy. Two of them recovered after sepsis and central nervous system, muscular and subcutaneous cryptococcosis. The remaining two died. One had infectious diarrhoea (S. flexneri), peritoneal tuberculosis and sepsis (S. epidermidis); the other had bacterial meningitis, erysipelas, beta-hemolytic Streptococcus sepsis and miliary tuberculosis. Their immunodeficiency was attributed to enteric protein loss and/or malabsorption and malnutrition and was recognized by reduced response to delayed hypersensitivity skin tests in four patients and hypogammaglobulinemia in three of them. The authors discuss the need for prospective studies to be carried out, aiming at the mechanisms involved in secondary infections. Alternatives for maintaining the patients' adequate nutritional state should be investigated, to guarantee proper immune response and thus the ability to control intervening infections in patients with juvenile paracoccidioidomycosis.

[Bone marrow involvement and eosinophilia in paracoccidioidomycosis]. / Comprometimento da medula óssea e eosinofilia na paracoccidioidomicose.

The authors described three acute paracoccidioidomycosis patients with bone marrow involvement. P. brasiliensis yeast forms were observed in bone marrow smears of all them, and in one case, culture also revealed fungus growth. The mononuclear phagocytic system involvement, the blood eosinophilia and the negative skin hypersensibility responses were emphasized in all of them, as well as the severity of the disease in one case, with disseminated bone lesions and 20.260 eosinophils/mm3 in peripheral blood. The authors discuss the possible role of eosinophil in the host-parasite interaction in paracoccidioidomycosis, suggesting that TH 2 subpopulation activation and increased IL 5 and GM-CSF secretions may be responsible by eosinophilia in the most severe case.

Raiva humana tratada com interferon por via intratecal / Human rabies treated with interferon by intramuscular way

Relata-se um caso de raiva humana submetido a tratamento com interferon leucocitário humano injetado por via ventricular, através de reservatório de Rickham, e parte por via intramuscular. As doses diárias injetadas foram de 5 x10**6 unidades por via intraventricular e de 20 x 10**6 unidades por via intramuscular, a partir do 7§ dia de doença durante nove dias, quando entäo ocorreu o óbito em conseqüência de sepse por Klebsiella pneumoniae (16§ dia de doença). O vírus da raiva foi isolado inicialmente através de biopsia do tecido nervoso cerebral. O nível de interferon no sangue e no líquor era inferior a 10 U/ml antes do início do tratamento. O esquema terapêutico utilizado propiciou títulos elevados de interferon no sangue e no líquor 10 a 2.000 vezes maiores que aqueles atingidos usualmente na infecçäo natural. O nível residual, após 24 horas, foi de 212 ñ 14 U no sangue e 451 ñ 81 U no líquor. Foi observada menor soroconversäo (anticorpos neutralizantes) contra o vírus rábico (1/75 a partir do 13§ dia), em conseqüência da imunossupressäo induzida pelo interferon, provavelmente

Mathematical model of Klebsiella pneumoniae resistance to amikacin and gentamicin.

1. The resistance of Klebsiella pneumoniae to amikacin and gentamicin was studied by a mathematical model to predict the rate of sensitivity decrease. The results accurately matched experimental data, showing that the model is a reliable predicting tool. 2. The observations were carried out over six years and included 2677 cultures that were positive for K. pneumoniae. At the beginning of the observation period, 85.7% of the cultures were sensitive to amikacin and 40.8% were sensitive to gentamicin. Sensitivity to amikacin showed a surprisingly rapid decrease; at the end of the experimental period, amikacin and gentamicin sensitivities were 33.3% and 27.8%, respectively. 3. We conclude that patterns of resistance of other bacteria could be investigated using this method.

Avaliacao da aplicabilidade da radiacao gama no preparo da vacina antipertussis. / Evaluation of the applicability of gamma rays in the preparation of pertussis vaccine

Usando o teste de toxidez e protecao em camundongos, doze lotes de vacina antipertussis foram inativadas utilizando o metodo classico e o metodo por radiacao ionizante gama, obtida a partir do cobalto 60 de fonte radioativa J.S 7.400, Atomic Energy of Canada Limited, e conservadas em camara fria a 2oC a 8oC por tres meses. No grupo submetido a radiacao houve inativacao de bacterias, porem nao se obteve destoxificacao imediata. A imunogenicidade da vacina nao foi alterada pela radiacao, tendo a atividade protetora ocorrido semelhantemente nos dois metodos

Tratamento especifico do tetano com uma fracao - F(ab') - da imunoglobulina antitetanica injetada por via raquidiana. / Specific treatment of tetanus with a fraction - F(ab') - of the antitetanic immunoglobulin injected intrathecally

Sao apresentados os resultados preliminares do tratamento especifico de 26 casos de tetano humano com a fracao F(ab') da antitoxina tetanica equina injetada por via intratecal. O indice de letalidade observado foi de 3,8%. Considerando-se apenas os casos de maior gravidade (grau III) o indice de letalidade foi de 10%. Tais resultados encorajadores vem corroborar os resultados de experimentacoes previas em animais de laboratorio, realizados por outros pesquisadores, onde a importancia da via sub-aracnoidea e de fracoes de baixo peso molecular de gamaglobulina antitetanica foram demonstradas importantes para permitir o acesso da antitoxina aos neuronios das membranas pre-sinapticas da medula espinal a fim de deslocar e neutralizar a toxina fixada aos receptores dos gangliosideos