Polyspikes and Rhythmic Polyspikes During Volatile Induction of General Anesthesia With Sevoflurane Result in Bispectral Index Variations.

BACKGROUND: Although electroencephalography (EEG)-based indices may show artifactual values, raw EEG signal is seldom used to monitor the depth of volatile induction of general anesthesia (VIGA). The current analysis aimed to identify whether bispectral index (BIS) variations reliably reflect the actual depth of general anesthesia during presence of different types of epileptiform patterns (EPs) in EEGs during induction of general anesthesia. METHODS: Sixty patients receiving either VIGA with sevoflurane using increasing concentrations (group VIMA) or vital capacity (group VCRII) technique or intravenous single dose of propofol (group PROP) were included. Monitoring included facial electromyography (fEMG), fraction of inspired sevoflurane (FiAA), fraction of expired sevoflurane (FeAA), minimal alveolar concentration (MAC) of sevoflurane, BIS, standard EEG, and hemodynamic parameters. RESULTS: In the PROP group no EPs were observed. During different stages of VIGA with sevoflurane in the VIMA and VCRII groups, presence of polyspikes and rhythmic polyspikes in patients' EEGs resulted in artifactual BIS values indicating a false awareness/wakefulness from anesthesia, despite no concomitant change of FiAA, FeAA, and MAC of sevoflurane. Periodic epileptiform discharges did not result in aberrant BIS values. CONCLUSION: Our results suggest that raw EEG correlate it with values of BIS, FiAA, FeAA, and MAC of sevoflurane during VIGA. It seems that because artifactual BIS values indicating false awareness/wakefulness as a result of presence of polyspikes and rhythmic polyspikes in patients' EEGs may be misleading to an anesthesiologist, leading to unintentional administration of toxic concentration of sevoflurane in ventilation gas.

Variations in Values of State, Response Entropy and Haemodynamic Parameters Associated with Development of Different Epileptiform Patterns during Volatile Induction of General Anaesthesia with Two Different Anaesthetic Regimens Using Sevoflurane in Comparison with Intravenous Induct: A Comparative Study.

BACKGROUND AND OBJECTIVES: Raw electroencephalographic (EEG) signals are rarely used to monitor the depth of volatile induction of general anaesthesia (VIGA) with sevoflurane, even though EEG-based indices may show aberrant values. We aimed to identify whether response (RE) and state entropy (SE) variations reliably reflect the actual depth of general anaesthesia in the presence of different types of epileptiform patterns (EPs) in EEGs during induction of general anaesthesia. MATERIALS AND METHODS: A randomized, prospective clinical study was performed with 60 patients receiving VIGA using sevoflurane with the increasing concentrations (group VIMA) or the vital capacity (group VCRII) technique or an intravenous single dose of propofol (group PROP). Facial electromyography (fEMG), fraction of inspired sevoflurane (FiAA), fraction of expired sevoflurane (FeAA), minimal alveolar concentration (MAC) of sevoflurane, RE and SE, and standard electroencephalographic evaluations were performed in these patients. RESULTS: In contrast to periodic epileptiform discharges, erroneous SE and RE values in the patients' EEGs were associated with the presence of polyspikes (PS) and rhythmic polyspikes (PSR), which were more likely to indicate toxic depth rather than false emergence from anaesthesia with no changes in the FiAA, FeAA, and MAC of sevoflurane. CONCLUSION: Calculated RE and SE values may be misleading during VIGA when EPs are present in patients' EEGs. During VIGA with sevoflurane, we recommend monitoring raw EEG data in scientific studies to correlate it with potentially erroneous RE and SE values and the end-tidal concentration of sevoflurane in everyday clinical practice, when monitoring raw EEG is not available, because they can mislead anaesthesiologists to reduce sevoflurane levels in the ventilation gas and result in unintentional true emergence from anaesthesia. Further studies are required to investigate the behaviour of EEG-based indices during rapid changes in sevoflurane concentrations at different stages of VIGA and the influence of polyspikes and rhythmic polyspikes on the transformation of EEG signals into a digital form.

Epileptiform EEG patterns during different techniques of induction of general anaesthesia with sevoflurane and propofol: a randomised trial.

BACKGROUND: The aim of the study was to assess the influence of volatile induction of general anaesthesia with sevoflurane using two different techniques and intravenous anaesthesia with propofol on the possible presence of epileptiform electroencephalograph patterns during the induction of general anaesthesia. METHODS: Sixty patients (age 18-70 years) were recruited. Exclusion criteria included history of epilepsy, neurological or neurosurgical diseases, pre-existing EPs in initial EEG recordings, medication interfering with EEG patterns. Patients were randomly allocated into three different groups: A (sevoflurane, increasing concentrations technique); B (sevoflurane, vital capacity technique); C (intravenous propofol). The clinical and instrumental monitoring included arterial blood pressure, heart rate, standard electrocardiography II, arterial oxygen saturation, facial electromyography, fraction of inspired sevoflurane, fraction of expired sevoflurane, minimal alveolar concentration of sevoflurane, and BIS. RESULTS: Neurophysiological analysis of EEGs showed different EPs: polyspikes (PS), rhythmic polyspikes (PSR), and periodic epileptiform discharges (PED). EPs (p < 0.05) were observed in Group A (56%) and Group B (37%), but not in Group C. One patient in group B presented with clinical seizures. No significant differences in the vital parameters and anaesthesia parameters between groups was observed, regardless of the presence of EPs, which were associated with both low and more likely high (falsely indicating awakening from anaesthesia) BIS scores. CONCLUSION: Our study shows that the BIS score variations do not detect epileptiform activity, which was associated with both low and high scores. The sevoflurane concentration reached either sedative or toxic concentrations.

[Usage of beta-adrenolytic agents in patients with chronic pulmonary obstructive disease]. / Zastosowanie antagonistów receptora beta-adrenergicznego u chorych na przewlekla obturacyjna chorobe pluc.

Beta-blockers are commonly used in the contemporary pharmacotherapy. They are considered the drugs of choice in the treatment of many, especially cardiological, disorders. Chronic obstructive pulmonary disease (COPD) is a very common disease, which is classified as the fourth cause of the chronic morbidity and mortality in the USA. Frequent occurrence, as well as the fact that some risk factors, such as cigarette smoking, are common for both COPD and cardiovascular diseases cause that the number of patients suffering from their coexistence is increasing. Because first beta-blockers had a strong bronchoconstrictory effect, their use is contraindicated in conditions associated with airway obstruction. This review was aimed to investigate the safety of using of beta-blockers in patients with COPD. We try to answer whether selective beta-blockers and so-called hybrid beta-blockers are safe for patients suffering from this disorder. We also try to elaborate some therapeutic recommendations.

Hormonal supplementation in endocrine dysfunction in critically ill patients.

One of the greatest challenges for a physician is a critically ill patient. Regardless of the reason for an admission to the Intensive Care Units (ICU) (e.g. myocardial infarction, severe pneumonia, trauma or many others) each of the above-mentioned conditions impairs homeostasis including instability of the endocrine system. The observed alterations in serum glucose level or clinical signs of hormonal imbalance alarm practitioners and prompt them to an intervention. However, side-effects of administered drugs have to be always considered, because every intervention in the endocrine system may have various consequences or prove itself maleficent. Since critical condition causes numerous changes in the hormonal system, the definition of endocrine gland failure in the ICU patients should differ from the definition related to the general population. This review is aimed at describing alterations, diagnosis and treatment options for an impaired carbohydrate metabolism and inadequate response of the adrenal and thyroid endocrine axis. It has been written in order to aid the choice between "the watch and wait strategy" and aggressive pharmacological intervention. Furthermore, several standard and innovative therapeutic procedures were described and, if possible, compared. Recent articles have been included in order to show current views on the up-to-date clinical approach.