Azize Bestas

Effect of sevoflurane anesthesia on the severity of renal histopathologic changes in rabbits pretreated with gentamicin: A controlled, investigator-blinded, experimental study

BACKGROUND Inorganic fluoride and compound A are potential nephrotoxic products of sevoflurane, a halogenated inhalational general-anesthetic drug. OBJECTIVE The aim of this study was to microscopically examine the effect of sevoflurane on the severity of renal histopathologic changes in rabbits pretreated with gentamicin. METHODS In this controlled, investigator-blinded, experimental study at the Firat University School of Medicine, Elazig, Turkey, male New Zealand white rabbits (age range, 6-8 months; weight range, 2600-3400 g) were randomly divided into 4 groups of equal size. The gentamicin group received IM gentamicin 10 mg/kg · d(-1) for 10 days. Rabbits in the sevoflurane group received pH-balanced saline solution at a volume of 10 mg/kg · d(-1) for 10 days, equivalent to the volume of gentamicin administered to the gentamicin group. On day 11, anesthesia was induced with 8% sevoflurane in 50% oxygen and air using a suitable facemask. When a sufficient depth of anesthesia (loss of eyelash reflex and tolerance to tail-clamp stimuli) was reached (without a muscle relaxant), the rabbits were intubated (3-mm ID) and allowed to breathe spontaneously. End-tidal or end expiratory concentration of sevoflurane was then decreased to 4% and the rabbits were anesthetized at a flow rate of 4 L/min for 4 hours. The rabbits in the gentamicin + sevoflurane group were treated with IM gentamicin at a dosage of 10 mg/kg · d(-1) for 10 days. On day 11, they were exposed to sevoflurane, as described for the sevoflurane group. The control group received IM pH-balanced saline solution for the duration of the study. Twenty-four hours after treatment completion, all rabbits were euthanized and kidney tissue samples were obtained. Histopathologic examinations were then carried out using light microscopy. Changes in renal histopathology were based on the percentage of acute tubular necrosis (ATN) and judged on a scale from none to severe. RESULTS Forty male New Zealand white rabbits (mean [SD] age, 7 [0.49] months; mean [SD] weight, 2900 [150] g) were divided into 4 groups of 10 rabbits each. Proximal renal tubule cell injury in the form of ATN (the mean score) was significantly greater in the 3 treatment groups than in the control group (all, P < 0.001), especially at the corticomedullary junction. In the 3 treatment groups, the most severe renal damage observed was rated as mild (10%-25%). More rabbits in the gentamicin + sevoflurane group had mild renal damage (7) than in the gentamicin group (4) or the sevoflurane group (4), but the between-group differences were not statistically significant. CONCLUSION In this experimental study of the effects of sevoflurane on the severity of renal histopathologic changes, a higher percentage of rabbits were observed to have greater renal damage in the gentamicin + sevoflurane group than the other groups. However, between-group differences did not reach statistical significance.

Effects of ondansetron and granisetron on postoperative nausea and vomiting in adult patients undergoing laparoscopic cholecystectomy: a randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND Postoperative nausea and vomiting (PONV) are common and potentially distressing adverse events (AEs) associated with surgery and anesthesia. In patients undergoing laparoscopic cholecystectomy (LC) without antiemetic prophylaxis, the incidence of PONV can be as high as 72%. OBJECTIVE The aim of this study was to investigate the prophylactic antiemetic effects of ondansetron and granisetron in patients undergoing LC when these agents are administered before the end of surgery. METHODS Patients classified by the American Society of Anesthesiologists physical status as I or II who were scheduled for elective LC were included in this randomized, double-blind, placebo-controlled study. Anesthesia was induced with thiopental 5 mg/kg and fentanyl 2 μg/kg, and was maintained with isoflurane 1% to 3% in 50% oxygen and 50% nitrous oxide and fentanyl as needed. Approximately 20 to 30 minutes before the end of the surgery, the patients randomly received either IV ondansetron 100 μg/kg (group O), IV granisetron 40 μg/kg (group G), or normal saline (group P). Plasma levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined preoperatively and 24 hours postoperatively. The patients were observed for 24 hours for PONV and other possible AEs. Postoperative pain intensity was determined using a 10-cm visual analogue scale. Four-point satisfaction scores were determined at 24 hours. RESULTS Ninety patients (69 women, 21 men) participated in the study. Demographic characteristics and operative data (duration of surgery and anesthesia and amount of intraoperative fentanyl) were similar in the 3 groups. The only AE reported by patients during the 24-hour observation period was nonsevere headache. The number of patients experiencing headache was similar in group P, group O, and group G (10 [33%] patients, 6 [20%], and 10 [33%], respectively). No significant changes were found in presurgical and postsurgical plasma levels of ALT and AST in any group. The mean (SD) satisfaction scores in group O and group G (3.0 [0.4] and 3.0 [0.6], respectively) were significantly higher than those in group P (2.5 [0.5]; both, P < 0.01). Immediately after surgery (period 0), significantly more patients in the placebo group (21 [70%]) experienced PONV compared with those in the ondansetron group (9 [30%]; P < 0.05) and the granisetron group (7 [23%]; P < 0.01). During the 24-hour observation period, a significantly greater number of patients in group P (18 [60%]) required a single dose of a rescue antiemetic drug compared with those in groups O and G (9 [30%] and 6 [20%], respectively; both, P < 0.01). CONCLUSIONS Patients administered ondansetron 100 μg/kg or granisetron 40 μg/kg 20 to 30 minutes before the end of LC had significantly higher PONV control during the 24-hour postoperative observation period than patients receiving placebo. However, there were no significant differences between the active treatment groups in the incidence of PONV, patient satisfaction, or AEs.

The Effects of Two Different Anaesthesia Techniques on Bispectral Index Values and Awareness During Off-Pump Coronary Artery Bypass Grafting

Objective. The aim of this study was to evaluate Bispectral Index values and awareness during two different anaesthesia regimens (fentanyl-propofol and fentanyl-midazolam) in patients undergoing off-pump CABG surgery. Methods. Fifty patients were included in the study. Patients were premedicated with midazolam and were randomly divided into two groups. Anaesthesia was induced with fentanyl (7–15 μg/kg), with either propofol (2–2.5 mg/kg, Group I) or midazolam (0.1–0.3 mg/kg, Group II) and vecuronium (0.1 mg/kg). Anaesthesia was maintained with fentanyl (15 μg/kg/h) together with either propofol (6 mg/kg/h) or midazolam (0.1 mg/kg/h). Depth of anaesthesia was adjusted according to clinical signs and haemodynamic responses. The level of sedation was monitored with Bispectral index continuously, but these levels were not shown to the attending anaesthetist. Bispectral index values were recorded for nine phases. Twenty-four hours after the operation, the patients were interviewed to determine intraoperative awareness and recall. Results. In all patients, Bispectral index values were found to decrease after induction (in Group I, p = 0.005, in Group II, p = 0.008) with the mean values remaining below 60 for all phases. The differences between the groups were not statistically significant in inter-group comparison. No patients were noted to recall the sounds presented during the operation and the preoperative events. Conclusions. BIS monitoring with clinical signs may be used to assess the adequacy of both types of anaesthesia techniques as well as to detect awareness during off-pump CABG surgery.

Evaluation of levobupivacaine passage to breast milk following epidural anesthesia for cesarean delivery

BACKGROUND Following maternal administration, local anesthetics pass into breast milk. In the present study, we aimed to compare the passage of levobupivacaine and bupivacaine into breast milk following epidural anesthesia for cesarean delivery. METHODS A total of 20 women undergoing elective cesarean delivery under epidural anesthesia were randomized to receive either 0.5% levobupivacaine or 0.5% racemic bupivacaine via an epidural catheter. Immediately before and 30min, 1h, 2h, 6h, 12h and 24h after administration of epidural local anesthetic, maternal blood and breast milk samples were taken simultaneously. Drug concentrations in plasma and milk were determined via high-performance liquid chromatography. The infants drug exposure was determined by calculating milk/plasma ratios of levobupivacaine and bupivacaine. RESULTS Both levobupivacaine and bupivacaine were detected in breast milk 30min after epidural administration. Concentrations of both agents showed constant and similar decreases in milk and plasma and were nearly undetectable at 24h. The milk/plasma ratios were 0.34±0.13 for levobupivacaine and 0.37±0.14 for bupivacaine. CONCLUSIONS Both levobupivacaine and bupivacaine pass into breast milk following epidural administration. The concentration of both drugs was approximately three times lower in breast milk than in maternal plasma.

As an analgesic ketamine versus fentanyl for total intravenous anesthesia.

90th min). As well as recovery characteristics of anesthesia, the severity of postoperative pain were also monitored by Visual Analogue Scale (score 0-10) at 15th, 30th, 45th, 60th, 75th and 90th min, postoperatively. In addition, blood samples were taken for determining serum adrenaline, noradrenaline, renin, aldosterone, adrenocorticotropic hormone (ACTH), glucose and cortisol levels at three time points (before and during anesthesia, 24th h, postoperative). One-way ANOVA with Tukey Honestly Significant Difference, Chi-square or Fisher’s exact tests were used for statistical analysis.