Comparison of entropy and bispectral index values during propofol induction

To identify the entropy levels that would correspond to bispectral index [BIS] levels in general anesthesia [GA] induction in patients who will undergo elective lumbar disc surgery [LDS]. Thirty cases who underwent LDS under GA were included in our study after obtaining patient consent and approval of the Ethics Committee of Afyon Kocatepe University Medical School, Afyonkarahisar, Turkey, between January 01, 2004 to December 31, 2005. Bispectral index and entropy electrodes were applied at the same time to 30 cases in the study group. In order to assess the level of sedation during anesthesia and recovery, 'Observers Assessment of Alertness/Sedation' [OAA/S] scale was used. Bispectral index, state-entropy [SE], response-entropy [RE], and OAA/S values were recorded simultaneously. Induction OAA/S scores were in correlation with BIS and entropy values [RE-SE] in 30 cases. A significant difference was found between BIS and entropy induction values [p=0.0398]. Induction mean arterial pressure and heart rate values at 30, 60, 90, and 120 seconds were lower than the values of the control, which was statistically significant [p=0.0412]. During the induction of GA, we found entropy values to be more sensitive and they demonstrated a more rapid increase than BIS. Therefore, it would be safer to monitor entropy while using agents of induction that might cause severe hypotension. Induction agents that might cause severe hypotension could be more safely administered under entropy monitoring

Which is more effective in reducing secondary brain damage resulting from cyclooxygenase expression following traumatic brain injury: calcium channel blockers or cox inhibitors?

To evaluate localizations of cyclooxygenase [COX]-1 and COX-2 following traumatic brain injury [TBI] and the effects of 2 therapeutic agents on COX inhibition. Forty rabbits were used in this study for developing a TBI model and divided into 4 groups [n=10] at Afyon Kocatepe University School of Medicine, Afyonkarahisar, Turkey in June 2004. Differential cellular COX-1 and COX-2 protein expression profiles were analyzed following TBI, and the effects of 2 therapeutic agents, indomethacin and nimodipine, on COX inhibition were evaluated immunohistochemically. This study revealed that COX-1 and COX-2 protein expression were significantly increased in vascular endothelial, smooth muscle cells, and CD68+ microglia/macrophages following TBI. Indomethacin inhibited the COX expression in glial cells more than nimodipine, however, both did not affect endothelial COX-1 and COX-2 expression. The restricted accumulation of COX-1 at the perilesional area points to an acute inflammatory response and the role of COX-1 in TBI. This study revealed that COX-1 expression should be a pharmacological target following TBI, and COX-2 should also be evaluated in this aspect, and indomethacin is more effective than nimodipine for blocking COX-1

Spontaneous regression of lumbar disc herniation

We present 3 cases of spontaneous regression of lumbar herniated disc. The disc regression correlated with clinical improvement documented by MRI studies. Although the phenomenon of spontaneous disappearance of decrease in size of herniated disc fragments is well known, the exact mechanism underlying this process remains unclear. We discuss 3 possible explanations for disc regression: retraction into the vertebral space, dehydration/shrinkage, and resorption due to inflammatory reaction

Elevated intracranial pressure management

The treatment strategy for increased intracranial pressure [ICP] management includes decisions on head and body position, hypothermia, ventilation, anesthetics, osmotic drugs and surgical procedures. We can treat sudden increases in ICP using osmotic agents, some anesthetics and short episodes of mild hyperventilation. Propofol seems to be suitable for sedation of the increased ICP patients. Surgical decompression of the cranium seems to improve the outcome of the younger patients [below 50 years old], especially children

Comparison of propofol and sevoflurane anesthesia by means of blood loss during endoscopic sinus surgery

The purpose of the present investigation is to examine whether induced hypotension with propofol or sevoflurane anesthesia improves the dryness of surgical field in endoscopic sinus surgery [ESS]. The study was performed between 1999 and 2002 in Celal Bayar University and Afyon Kocatepe University Hospitals, Turkey. Thirty-two patients [American Society of Anesthesiologists physical status I and III] with chronic sinusitis undergoing outpatient endoscopic sinus surgery under general anesthesia were studied to determine if anesthetic technique had an impact on estimated blood loss. The patients were allocated randomly into 2 groups. None of the patients were premedicated. Anesthesia was induced with propofol in both groups and maintained with propofol/fentanyl in the first group and sevoflurane/fentanyl in the second group. In both groups, controlled hypotension was used to improve surgical condition. There were no differences between the duration of surgery and intraoperative mean arterial blood pressure when comparing the 2 groups. The average estimated blood loss in the propofol group was 128.1 +/- 37.3 ml compared with an average estimated blood loss of 296.9 +/- 97.8 ml in the sevoflurane group [p<0.01]. General anesthesia based on propofol infusion may have the advantage of decreased bleeding compared with conventional inhalation agents. Therefore, making endoscopic surgery technically easier and safer by improving endoscopic visualization of the surgical field