Spectrum Analysis of Rat EEG during Infusion of Thiopental and Ketamine / 대한마취과학회지

The dose-ralated dffects of intravenous infusion of thiopental and ketamine on the rat EEG were evaluated quantitatively by spectrum analysis of EEG recorded from the rat scalp. The anesthetics were infused into jugular vein at various rates ranging from 0 to 8ug/min/g body weight, and then bipolar EEG was recorded from the rat scalp and tis spectrum were calculated by powere wpectrum analysis. the density of each bands(delta 1-3.25, theta 3.5-7.75, alpha 8-12.15, beta 1.13-17.75, beta 2.18-20.75, and beta 3.21-31.75Hz) and total density were derived from the spectrums. In visual inspection of conventional EEG, low doses of thiopental increased the amplitudes of spinles. but higher doses decreased the amplitube gradually to electrical silence with increase of infusion rates. During infusion of higher doses of ketamine, two types of EEG were identified by the spectral patterns:The one was the cases in which increases of the power density over all frequency ranges were observed, and the other was those in which marked increases of density in specific frequency were observed. In thiopental infusion, the densities of all bands were increased to peak at 1~2ug/min/g and therafter were decreased with higher rates of infusion. In ketamine infusion, the densities were increased when the infusion rate was increased. These results suggest that, by the changing patterns of the band densities dervied from spectrum analysis of EEG, not only the effect on EEG of thiopental of tetamine can be quantified but also their differences of mechanisms of action on brain be reflected.

Impossible Extubation due to Sutured Endotracheal Tube with the Bronchial Stump / 대한마취과학회지

Using endotracheal intubation technique, anesthesiolgoists have enjoyed many facilities in dealing with patients for operations. Better maintenance of airway, easy controllability of ventilation, easy removal of bronchial secretion, and the possibility of positive pressure without infiation of the stomach etc. consist part of the merits of endotracheal intubation technique. This time the author et al. experienced an impossible extubation case in which the endotracheal tube was sutured with the right bronchial stump after right lower lobectomy of the lung. After initial operation for pulmonary tuberculosis (explorative thoracotomy followed by right upper and middle bilobectomy), continuous bleeding led the patient to receive second operation and after this, extubation was impossible at the recovery room. Guessing the poslsibility of the tube sutured with the bronchial stump, we checked the chest film and a formal reading was made by the radiologist. Under the impression of the sutured-tube, a third operation was performed. In the operation field three stitches with the black silk 1-0 was made at the tip of the tube during the reinforcement process around the stump clipping was found. After removal of the stitches, extubation was possible without resistance and the patient transferred to the intensive care unit. To get rid of such a severe complication, anesthesiologist can not be over careful to check the position of the tube during the operation about the bronchial stump site.

A Cardiac Arrest during Surgery for Adrenal Tumor Causing Primary Aldosteronism / 대한마취과학회지

Primary aldosteronism is a rare syndrome which may reault from adenoma hyperplasia or carcinoma of the adrenal cortex and may thus be amenable to surgical correction. The findings of hypertension, hypoklemia and metabolic alkalosis suggest the diagnosis. This case report is to present the possibility of cardiac arrest due to hypokalemia during surgery for primary an adrenal tumor that was causing aldosteronism. This 25 year-old male who had a long history of aldosteronism, was admitted for surgery correction. Anesthesia was induced with thiopental sodium and was maintained with nitrous oxide and halothane. While the adrenal gland was being manipulated the patient appeared to have a sudden cardiac arrest with ventricular fibrillation as seen on the monitoring EKG. Cardiopulmonary resuscitation and D.C. shock to reverse the ventricular fibrillation was carried out immediately. The rest of the scheduled operation was continued and finished uneventfully. We concluded that the cause of the cardiac arrest in this case seemed to be a preoperative hypokalemia resulting from aldosteronism which was not corrected. In addition to that, the respiratory alkslosis from hyperventilation during the anesthesia even moreso lowered the preoperative level of hypokalemia.