İsmail Coşkuner

Effects of dexmedetomidine on the duration of anaesthesia and wakefulness in bupivacaine epidural block

Background: The purpose of this study was to examine the effects of intravenous dexmedetomidine on the duration of bupivacaine‐induced epidural anaesthesia and level of wakefulness and the respective side‐effects. Methods: Sixty ASA I–II patients were included in the study. Consecutive patients were allocated to groups according to the last digit (odd/even) of their admission numbers. All patients had epidural anaesthesia with bupivacaine 0.5% performed by the same experienced anaesthesiologist. In the first group, the patients were administered intravenous dexmedetomidine infusion just after the epidural block and continued during the operation, while those in the second group were administered physiologic saline infusion at the same amount and duration. Results: The recovery time of sensory block was significantly longer in the first group. The bispectral index values were lower in the first group than in the second. Also, heart rate was significantly lower in Group I than in Group II. Regarding side‐effects, shivering was significantly less frequent in the first group, whereas there was a significant increase in the requirement of atropine in the first group as dexmedetomidine caused bradycardia. Conclusion: Intravenous administration of dexmedetomidine prolonged the duration of epidural anaesthesia, provided sedation and had few side‐effects.

Comparison of the effects of desflurane and sevoflurane on the QTc interval and QT dispersion

Objective — The effects of desflurane and sevoflurane on QT interval and QT dispersion have been investigated in a prospective, double-blind, randomized study of patients undergoing noncardiac surgery. Interventions — Sixty American Society of Anaesthesiologists physical status I-II adult patients were randomly assigned to two groups.Anaesthesia was induced with inhalation of desflurane (desflurane group) or sevoflurane (sevoflurane group) in increasing concentrations to 3 minimal alveolar concentration level. The maintenance of anaesthesia was provided with 2 minimal alveolar concentration agents in both groups until the end of the study. Electrocardiogram, heart rate and blood pressure were recorded as follows: before premedication, before induction, 1 and 3 min after the induction of anaesthesia, after the administration of vecuronium and after the tracheal intubation. The induction times and the complications were recorded. Measurements and results — The QTc interval was significantly more prolonged with desflurane than with sevoflurane at the first and third minute after the induction, and at the third minute after the administration of vecuronium.There were no significant differences in the QT dispersion between the two groups. Heart rate and blood pressure were found to be significantly higher in the desflurane group. Conclusion — The QTc interval was more prolonged with desflurane than sevoflurane, and QT dispersion was normal with both agents.

The Effect of Patient Positioning on Amount of Intraoperative Bleeding in Rhinoplasty: A Randomized Controlled Trial

BackgroundThere is a rich blood flow to the mucosa in the nasal region. In rhinoplasty, surgical procedures are performed in a narrow and confined space. So bleeding during surgery reduces visibility which can complicate the procedure. This study investigated the effects of the patient position on amount of intraoperative bleeding during surgical procedures.Patients and MethodsThis randomized controlled trial was conducted on 71 patients who underwent elective rhinoplasty. The patients were operated on in three groups. Group 1 consisted of 23 patients who were operated on in the supine position; Group 2 included 28 patients who were operated on using a 15° angle reverse Trendelenburg position; Group 3 consisted of 20 patients who were operated on at a 20° angle reverse Trendelenburg position.ResultsThere were statistically significant differences between the groups in regard to surgeon satisfaction and the amount of intraoperative bleeding. The amount of intraoperative bleeding in Group 1 was significantly higher than those of Groups 2 and 3, and surgeon satisfaction was lower.ConclusionsReverse Trendelenburg position reduces intraoperative bleeding in rhinoplasty patients while facilitating the procedure compared to the supine position. Surgery at a 15° angle reverse Trendelenburg position provides the optimum working conditions by both significantly reducing intraoperative bleeding and allowing for comfortable conditions for the surgeon.Level of Evidence IThis journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Protective effects of intravenous anesthetics on kidney tissue in obstructive jaundice

AIM To evaluate the protective effects on kidney tissue of frequently used intravenous anesthetics (ketamine, propofol, thiopental, and fentanyl) in rats with obstructive jaundice. METHODS There is an increased incidence of postoperative acute renal failure in patients with obstructive jaundice. Thirty-two Wistar-albino rats were randomly divided into four equal groups. Laparatomy was performed on each animal in the four groups and common bile ducts were ligated and severed on day 0. After 7 d, laparotomy was again performed using ketamine, propofol, thiopental, or fentanyl anesthesia whose antioxidative properties are well known in oxidative stress in a rat liver model of obstructive jaundice. After 2 h, the rats were sacrificed. Renal tissue specimens were analyzed for catalase, superoxide dismutase and malondialdehyde enzymes activities. All values are expressed as the mean ± SD. P values less than 0.05 were considered statistically significant. RESULTS All animals survived without complications until the end of the study. Enlargement in the bile duct and obstructive jaundice were observed in all rats. Catalase was found to be significantly lower in the fentanyl group than in the ketamine (P = 0.039), propofol (P = 0.012), and thiopental (P = 0.001) groups. Superoxide dismutase activities were similar in all groups (P > 0.05). Malondialdehyde was found to be significantly lower in the ketamine group than in the propofol (P = 0.028), thiopental (P = 0.002) and fentanyl (P = 0.005) groups. Malondialdehyde was also lower in the fentanyl group than in the thiopental group (P = 0.001). The results showed that obstructive jaundice sensitizes renal tissue to damage under the different anesthetics. CONCLUSION Among the agents tested, ketamine and propofol generated the least amount of oxidative stres on renal tissues in this rat model of obstructive jaundice created by common bile duct ligation. The importance of free radical injury in renal tissue in obstructive jaundice under different intravenous anesthetics during hepatobiliary and liver transplant surgery should be considered for prevention of postoperative acute renal failure.

Anaesthetic Management of a Neonate with Giant Cystic Hygroma.

Cystic hygroma, which originates from embryonic lymphoid tissue, is a benign tumour without any potential for malignancy. It is commonly located in the neck area. Anaesthetic management of a large neck mass may be challenging due to difficulty in intubation and the severe haemodynamic effects of surgical removal of a giant tumour. Serious consequences such as sudden airway occlusion resulting in hypoventilation and hypoxemia may arise. We present the anaesthetic management of a 15-day-old infant who underwent surgical removal of a cystic hygroma located on the left side of the neck. Anaesthesia was induced by mask ventilation with sevoflurane in 100% oxygen and intubation was carried out while maintaining spontaneous ventilation. The endotracheal tube was sutured to the tip of the right lip to avoid movement or extubation. In addition to arterial cannulation for invasive blood pressure monitoring, central venous catheterization for perioperative fluid management was put in place. After 6 hours of surgery, the infant was transported to the neonatal intensive care unit and was extubated without difficulty the next day. Facial nerve injury was observed to be temporary.