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Background: Systemic and hemodynamic complications associated with stereotactic and Mayfield pin insertion pain and is one of the major problems in neuro-anesthesiology. The aim of this study was to decrease patients' hypertensive response to pain and stressful condition of the disease which may bring about problems during operation. Materials and Methods: In a randomized, double-blind clinical trial, thirty 16-65 year old ASA I and II patients at Al-Zahra Hospital of Isfahan were analyzed between September 2008 and November 2009. The level of pain according to VAS of pain was obtained from the patients in three stages: After pin insertion (stage 1), while returning from MRI (stage 2), and at the end of the procedure (stage 3) and recorded in the questionnaire. Data were analyzed through SPSS software. Results: The mean VAS of pin insertion pain for lidocaine in the three stages was 5.46, 5.00, and 2.46 and for bupivacaine was 5.76, 3.76 and 1.40, respectively (P<0.005). This indicated a significant difference between lidocaine and bupivacaine. Conclusion: As stereotactic operations take 3 to 3.5 hours on average, the use of bupivacaine instead of lidocaine is highly recommend during pin insertion.

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Background: Familiarity with different methods and medications in anesthesia and producing sufficient depth of anesthesia are very important in anesthesia practice. Due to the central analgesic and sedative effect of lidocaine in the presence of the sufficient blood level, it can be used for general anesthesia. This study was carried out to compare the effect of halothane with lidocaine infusion on BIS during maintenance of anesthesia.

Materials and Methods: In this randomized double-blind controlled clinical trial, 66 patients scheduled for elective inguinal herniorrahaphy were randomized into two equal groups. For maintenance, one group received halothane (1%) with O2-N2O and another group received lidocaine infusion (100 &mug/kg/min). BIS was checked every 5 minutes for half an hour. Statistical analysis of data was done by Chi-square and T-test through SPSS software. P-values less than 0.05 were considered meaningful.

Results: Mean of BIS was 65.72 in the lidocaine group and 56.7 in the halothane group during the first 30 minutes. There was a significant statistical difference between the two groups (p<0.05).

Conclusion: Mean of BIS in lidocaine group was higher than that in the halothane group. If this indicates the presence of a light level of anesthesia, increasing the dose of hypnotics and opioids leads to an increase in the depth of anesthesia. However, since there is not any device for monitoring the effect of opioids on the central nervous system and the level of anesthesia, simultaneous monitoring of BIS and hemodynamic parameters seems to be a more reasonable idea.

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Abstract

Background: Pain is a protective process in the body. There are different pathways for pain control in the central nervous system. Descending pain control system is one of pathways. The periaqueductal gray (PAG) is a structure known for its role in pain transmission and modulation. The aim of this study is to investigate the percent of interaction between the left and right PAG in unilateral left foot induced pain.

Materials and Methods: In this study, 60 rats (280+30g) in six groups were used (3test groups and 3 controls groups). In test groups, 0.5 microliter lidocaine was injected in the left PAG, right PAG or both to make local anesthesia. In control groups, 0.5 microliter of normal saline were injected. After 15 minutes, 50 microliter of 2.5% of formalin were injected subcutaneously to right hind paw of rats and nociception was detected in every 15 seconds for one hour.

Results: The induction of unilateral pain (left hind paw) in rats, can affect not only the ipsilateral but also the contralateral PAG nucleus.

Conclusion: This study showed that the left and right PAG nuclei have significant role on unidirectional nociception in formalin test in rats. The contralateral PAG, however, has a minor effect on nociception.

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Introduction: Some intracranial surgeries must be performed while the patient is awake. Awake craniotomy is an intracranial surgical procedure in which the patient remains in a state of controlled consciousness while the surgery is performed. The aim of this study was to present a case of intracranial surgery to remove a tumor in the right frontal cortex using awake craniotomy.
Case Report: This report describes the anesthetic management of a 22-year-old male undergoing craniotomy with a fully awake technique. This was the first case of craniotomy performed entirely awake (from the beginning to the end of the operation) at Arak University of Medical Sciences and Valiasr Hospital in Arak, After preoperative preparation and evaluation, scalp nerve blocks targeting the cranial nerves innervating the scalp and head muscles were administered at specific sites. Mild sedation was provided using oxygen supplementation, followed by surgical incision. The lesion was examined intraoperatively while the patient remained awake, and the tumor was safely excised under full wakefulness. A combination of local and regional anesthesia and light intravenous sedation was utilized. Two types of local anesthetics, lidocaine 1.5% and bupivacaine 2.5%, were used for anesthesia, as well as intravenous sedatives and anesthetics such as propofol, remifentanil, and dexmedetomidine were administered for sedation. Throughout the operation, the patient was awake and breathing spontaneously, and the function of the brain nerves during the operation could be evaluated. Finally, the patient's surgery was performed without any complications and in stable condition, and the patient was transferred to the intensive care unit in good general condition, awake and fully alert.
Conclusions: Although maintaining analgesia and hemodynamic and adequate ventilation during fully awake craniotomy poses challenges, this technique is critical for intraoperative monitoring of cranial nerve function and preventing neurological deficits. By precisely administering scalp nerve blocks and carefully titrating sedatives (propofol, remifentanil, dexmedetomidine), we successfully performed the procedure under full wakefulness. With this method, potential surgical complications are prevented, and the patient also experiences satisfactory painlessness. Applying this technique was satisfactory for our patient.