Electrical Changes in Deeper Cortical Structures During Balanced General Anesthesia with the Aim on Inhalation Anesthetics Effects

There are many theories that attempt to explain the mechanisms of the effects of inhalation anesthetics - from simpler, pursuing individual effects of anesthetics on the level of the ion channels, to more complex that are looking for uniform global changes in brain activity common to several agents. However, we still don’t have satisfactory and adequate conclusions.

We examined a sample of 39 patients undergoing thoracic surgery at the Clinic of Thoracic Surgery under general anesthesia (GA) and we registered their electroencephalographic (EEG) signals before and during operation. After induction of GA by intravenous (i.v.), we used inhalation anesthetics to maintain GA. We used sevoflurane (SEV) in 20 patients and desflurane (DES) in 19 patients. Then we obtained the EEG data and processed them through mathematical and statistical analysis, to discover any changes of electrical activity in the brain during thoracic surgery under GA.

The era of digital recording EEG and present possibilities of modern computer techniques allow quantitative analysis of obtained data. We performed the analysis with the software LORETA (low resolution brain electromagnetic tomography). It is a relatively new research method, which in a similar way as computed tomography (CT) or magnetic resonance imaging (MRI) displays even deeper brain electrical activity, which is hiddeen for a classical EEG approach.

We described the general changes in brain electrical activity of the deeper cortical structures within the traditional frequency bands (d, q, a, b and g) during GA at 5 mm spatial resolution. We have shown that the source of the well-known cortical EEG changes after the effect of used inhalation anesthetics is caused by changes situated in the deeper brain structures, particularly the limbic system. Significant changes occurred in the cingulate gyrus for most of an EEG frequency ranges. When comparing the data of patients anesthetised with SEV and DES we found similar changes within the d and q rhythms and then the global changes of EEG activity followed during GA.

Therapeutic approach to a child with acute respiratory distress syndrome: a report of two cases

The course of a respiratory disorder in a child may end up in respiratory failure. There are also acute non-respiratory diseases which have a great influence on the respiratory functions and often lead to the acute lung injury and sometimes to the acute respiratory distress syndrome (ARDS). A feature of respiratory function deterioration is changed in the surfactant system. We often see inhibition of its synthesis or damage to its structure. Therapy of children suffering from ARDS should be complex and rapid. Despite many recently published studies explaining the principle of this disorder, the mortality of ARDS is still very high (30-50%). There are several studies documenting successful administration of exogenous surfactant as part of a complex combined therapy of patients with ARDS, which leads to decreased mortality, improved oxygenation, and decreased need for aggressive artificial pulmonary ventilation. The authors of this article present their own experience with administration of exogenous surfactant in therapy of children with ARDS.

Changes of airway obstruction parameters in healthy children caused by mother's smoking during pregnancy

The present study was aimed at the assessment of the impact of mother smoking during pregnancy on changes of phase angle (phi) and T(me)/T(E) index in healthy children. A hundred and twenty seven children, divided according to age (<6 months and >6 months of age) and mother smoking anamnesis were investigated by noncalibrated respiratory inductive plethysmography in the supine position. We found statistically significant changes of phi (p<0.05) and T(me)/T(E) in healthy children of non-smoking mothers against a group of smoking mother's children of up to 6 months of age. These differences were not confirmed in children older than 6 months. Moreover, in the smoking mother group, we found statistically significant changes (P<0.05) of phi and T(me)/T(E) in children of up to 6 months of age in comparison with children older than 6 month. The results revealed a negative impact of mother smoking during pregnancy represented by changes in airway obstruction parameters, which appeared especially in the group of youngest children.