Evaluation of renal oxygenization in laparoscopic pediatric surgery by near infrared spectroscopy.

PURPOSE: Increased intraabdominal pressure IAP may reduce renal blood flow (RBF). The study aims to evaluate the pneumoperitoneum effect on RBF by comparing renal regional oxygen saturation index (rSrO2) measured by near-infrared spectroscopy (NIRS) in pediatric patients having laparotomy and laparoscopy. METHODS: Of 58 patients having laparoscopy and laparotomy, 18 were excluded due to renal pathologies, combined open surgical procedures, and administration of inotropic drugs. Hemodynamic parameters and rSrO2 were recorded in laparoscopy (n = 20) and laparotomy (n = 20) groups before induction and with 5 min intervals up to 60 min and at post-extubation. RESULTS: Decrease in right renal rSrO2 at 45th and 60th min and 30th, 45th and 60th min in left were significant in the laparoscopy group compared to laparotomy group. In the laparoscopy group, reductions at T25, T30, T45, and T60 were significant in both renal rSrO2. Renal rSO2 increased to normal with desufflation. CONCLUSION: IAP with pneumoperitoneum may lead to renal hypoxia in children. Renal rSO2 returns to normal with desufflation. Renal NIRS monitorization might be needed in patients with renal parenchymal and vascular pathologies, solitary kidney, and multiorgan pathologies that may affect renal oxygenation.

The effects of nitrous oxide on controlled hypotension during low flow anesthesia.

BACKGROUND AND OBJECTIVES: We investigated the effect of Nitrous Oxide (N2O) on controlled hypotension in low-flow isoflurane-dexmedetomidine anesthesia in terms of hemodynamics, anesthetic consumption, and costs. METHODS: We allocated forty patients randomly into two equal groups. We then maintained dexmedetomidine infusion (0.1 µg.kg(-1).min(-1)) for 10 minutes. Next, we continued it until the last 30 minutes of the operation at a dose of 0.7 µg.kg(-1).hour(-1). We administered thiopental (4-6 mg. kg(-1)) and 0.08-0.12 mg.kg(-1) vecuronium bromide at induction for both groups. We used isoflurane (2%) for anesthesia maintenance. Group N received a 50% O2-N2O mixture and Group A received 50% O2-air mixture as carrier gas. We started low-flow anesthesia (1L.min(-1)) after a 10-minute period of initial high flow (4.4L.min(-1)). We recorded values for blood pressure, heart rate, peripheral O2 saturation, inspiratory isoflurane, expiratory isoflurane, inspiratory O2, expiratory O2, inspiratory N2O, expiratory N2O, inspiratory CO2, CO2 concentration after expiration, Minimum Alveolar Concentration. In addition, we determined the total consumption rate of fentanyl, dexmedetomidine and isoflurane as well as bleeding. RESULTS: In each group the heart rate decreased after dexmedetomidine loading. After intubation, values were higher for Group A at one, three, five, 10, and 15 minutes. After intubation, the patients reached desired hypotension values at minute five for Group N and at minute 20 for group A. MAC values were higher for Group N at minute one, three, five, 10, and 15 (p<0.05). FiO2 values were high between minute five and 60 for Group A, while at minute 90 Group N values were higher (p<0.05). FiIso (inspiratuvar isofluran) values were lower in Group N at minute 15 and 30 (p<0.05). CONCLUSION: By using dexmedetomidine instead of nitrous oxide in low flow isoflurane anesthesia, we attained desired MAP levels, sufficient anesthesia depth, hemodynamic stability and safe inspiration parameters. Dexmedetomidine infusion with medical air-oxygen as a carrier gas represents an alternative anesthetic technique.

Efeitos do óxido nitroso em hipotensão controlada durante anestesia com baixo fluxo / The effects of nitrous oxide on controlled hypotension during low flow anesthesia / Efectos del óxido nitroso en la hipotensión controlada durante la anestesia con bajo flujo

JUSTIFICATIVA E OBJETIVOS: Investigamos o efeito do óxido nitroso (N2O) em hipotensão controlada durante anestesia com baixo fluxo (isoflurano-dexmedetomidina) em termos de hemodinâmica, consumo de anestésico e custos. MÉTODOS: Quarenta pacientes foram randomicamente alocados em dois grupos. Infusão de dexmedetomidina (0,1 µg.kg-1.min-1) foi mantida por 10 minutos. Subsequentemente, essa infusão foi mantida até os últimos 30 minutos de operação a uma dose de 0,7 µg.kg-1.hora-1. Tiopental (4-6 mg.kg-1) e brometo de vecurônio (0,08 0,12 mg.kg-1) foram administrados na indução de ambos os grupos. Isoflurano (2%) foi administrado para manutenção da anestesia. O Grupo N recebeu uma mistura de 50% de O2-N2O e o Grupo A recebeu uma mistura de 50% de O2-ar como gás de transporte. Anestesia com baixo fluxo (1 L.min-1) foi iniciada após um período de 10 minutos de alto fluxo inicial (4,4 L.min-1). Os valores de pressão arterial, frequência cardíaca, saturação periférica de O2, isoflurano inspiratório e expiratório, O2 inspiratório e expiratório, N2O inspiratório e expiratório, CO2 inspiratório, concentração de CO2 após expiração e concentração alveolar mínima foram registrados. Além disso, as taxas de consumo total de fentanil, dexmedetomidina e isoflurano, bem como de hemorragia, foram determinadas. RESULTADOS: A frequência cardíaca diminuiu em ambos os grupos após a carga de dexmedetomidina. Após a intubação, os valores do Grupo A foram maiores nos minutos um, três, cinco, 10 e 15. Após a intubação, os valores de hipotensão desejados foram alcançados em 5 minutos no Grupo N e em 20 minutos no grupo A. Os valores da CAM foram mais altos no Grupo N nos minutos um, três, cinco, 10 e 15 (p < 0,05). Os valores da FiO2 foram mais altos entre 5 e 60 minutos no Grupo A, enquanto foram mais altos no Grupo N aos 90 minutos (p < 0,05). Os valores de Fi Iso (isoflurano inspiratório) foram menores no Grupo N nos minutos 15 e 30 (p < 0,05). CONCLUSÃO: O uso de dexmedetomidina em vez de óxido nitroso em anestesia com isoflurano pela técnica de baixo fluxo atingiu os níveis desejados de pressão arterial média (PAM), profundidade suficiente da anestesia, estabilidade hemodinâmica e parâmetros de inspiração seguros. A infusão de dexmedetomidina com oxigênio-ar medicinal como gás de transporte é uma técnica anestésica opcional.

BACKGROUND AND OBJECTIVES: We investigated the effect of Nitrous Oxide (N2O) on controlled hypotension in low-flow isoflurane-dexmedetomidine anesthesia in terms of hemodynamics, anesthetic consumption, and costs. METHODS: We allocated forty patients randomly into two equal groups. We then maintained dexmedetomidine infusion (0.1 µg.kg-1.min-1) for 10 minutes. Next, we continued it until the last 30 minutes of the operation at a dose of 0.7 µg.kg-1.hour-1. We administered thiopental (4-6 mg. kg-1) and 0.08-0.12 mg.kg-1 vecuronium bromide at induction for both groups. We used isoflurane (2%) for anesthesia maintenance. Group N received a 50% O2-N2O mixture and Group A received 50% O2-air mixture as carrier gas. We started low-flow anesthesia (1 L.min-1) after a 10-minute period of initial high flow (4.4 L.min-1). We recorded values for blood pressure, heart rate, peripheral O2 saturation, inspiratory isoflurane, expiratory isoflurane, inspiratory O2, expiratory O2, inspiratory N2O, expiratory N2O, inspiratory CO2, CO2 concentration after expiration, Minimum Alveolar Concentration. In addition, we determined the total consumption rate of fentanyl, dexmedetomidine and isoflurane as well as bleeding. RESULTS: In each group the heart rate decreased after dexmedetomidine loading. After intubation, values were higher for Group A at one, three, five, 10, and 15 minutes. After intubation, the patients reached desired hypotension values at minute five for Group N and at minute 20 for group A. MAC values were higher for Group N at minute one, three, five, 10, and 15 (p < 0.05). FiO2 values were high between minute five and 60 for Group A, while at minute 90 Group N values were higher (p < 0.05). Fi Iso (inspiratuvar isofluran) values were lower in Group N at minute 15 and 30 (p < 0.05). CONCLUSION: By using dexmedetomidine instead of nitrous oxide in low flow isoflurane anesthesia, we attained desired MAP levels, sufficient anesthesia depth, hemodynamic stability and safe inspiration parameters. Dexmedetomidine infusion with medical air-oxygen as a carrier gas represents an alternative anesthetic technique.

JUSTIFICATIVA Y OBJETIVOS: Investigamos el efecto del óxido nitroso (N2O) en hipotensión controlada durante anestesia con bajo flujo (isoflurano-dexmedetomidina) en términos de hemodinámica, consumo de anestésico y costes. MÉTODOS: Cuarenta pacientes fueron aleatoriamente divididos en dos grupos iguales. La infusión de dexmedetomidina (0,1 µg.kg-1.min-1) se mantuvo entonces por 10 minutos. En secuencia, esa infusión se mantuvo hasta los últimos 30 minutos de operación en una dosis de 0,7 µg.kg-1.hour-1. El tiopental (4-6 mg.kg-1) y el bromuro de vecuronio (0,08 0,12 mg.kg-1) fueron administrados en la inducción de ambos grupos. El Isofluorano (2%) fue administrado para el mantenimiento de la anestesia. El Grupo N recibió una mezcla de un 50% de O2-N2O y el Grupo A recibió una mezcla de un 50% de O2-ar como gas de transporte. La anestesia con bajo flujo (1 L.min-1) fue iniciada después de un período de 10 minutos de alto flujo inicial (4,4 L.min-1). Se registraron los valores de la presión arterial, frecuencia cardíaca, saturación periférica de O2, isoflurano inspiratorio, isoflurano espiratorio, O2 inspiratorio, O2 espiratorio, N2O inspiratorio, N2O espiratorio, CO2 inspiratorio, concentración de CO2 después de la espiración y concentración alveolar mínima. Además, de determinaron las tasas de consumo total de fentanil, dexmedetomidina e isoflurano, como también la de hemorragia. RESULTADOS: La frecuencia cardíaca disminuyó en ambos grupos después de la carga de dexmedetomidina. Después de la intubación, los valores del Grupo A fueron mayores en los minutos 1, 3, 5, 10 y 15. Después de la intubación, los valores de hipotensión deseados se alcanzaron en 5 minutos en el Grupo N y en 20 minutos en el grupo A. Los valores de la CAM fueron más altos en el Grupo N en los minutos 1, 3, 5, 10 y 15 (p < 0,05). Los valores de la FiO2 fueron más altos entre 5 y 60 minutos en el Grupo A, mientras que fueron más altos en el Grupo N a los 90 minutos (p < 0,05). Los valores de Fi Iso (isoflurano espiratorio) fueron menores en el Grupo N en los minutos 15 y 30 (p < 0,05). CONCLUSIONES: El uso de la dexmedetomidina en vez del óxido nitroso en la anestesia con el isoflurano por la técnica de bajo flujo, alcanzó los niveles deseados de presión arterial promedio (PAP), profundidad suficiente de la anestesia, estabilidad hemodinámica y parámetros de inspiración seguros. La infusión de dexmedetomidina con oxígeno / aire medicinal como gas de transporte es una técnica anestésica opcional.

Dexmedetomidine did not reduce the effects of tourniquet-induced ischemia-reperfusion injury during general anesthesia.

Ischemia reperfusion injury causes the release of free oxygen radicals. Free oxygen radicals initiate the production of toxic metabolites, such as malondialdehyde (MDA), through the lipid peroxidation of cellular membranes. Following lipid peroxidation, the antioxidant enzyme system is activated against reactive oxygen species (ROS) and attempts to protect cells from oxidative damage. There is a balance between the scavenging capacity of antioxidant enzymes and ROS. Because of this balance, the total antioxidant capacity (TAC) measurement is a sensitive indicator of the overall protective effects of the antioxidants. Alpha(2) receptor agonists are effective in preventing hemodynamic reactions during extremity surgeries by preventing the release of catecholamines secondary to tourniquet application. They have also been shown to possess preventive effects in various ischemia-reperfusion injury models. In our study, we examined the effects of dexmedetomidine on tourniquet-induced ischemia-reperfusion injury in lower extremity surgeries performed under general anesthesia. The effects of dexmedetomidine were measured with serum MDA and TAC levels. We studied 60 adult American Society of Anesthesiologists (ASA) physical status I or II patients undergoing one-sided lower extremity surgery with tourniquet. The patients were randomly divided into two groups. Group D was administered a dexmedetomidine infusion at a rate of 0.1µg/kg/minute(-1) for 10 minutes prior to induction and then at 0.7µg/kg/hour(-1) until 10 minutes before the end of the operation. The control group (Group C) received a saline infusion of the same amount and for the same period of time. General anesthesia was induced with thiopental, fentanyl, and rocuronium and maintained with nitrous oxide and sevoflurane in both groups. Venous blood samples were obtained before the administration of the study drugs (basal) at 1 minute before tourniquet release and at 5 and 20 minutes after tourniquet release (ATR). In both groups, MDA levels decreased at 5 and 20 minutes ATR when compared with the basal values (p<0.05). TAC levels decreased at 1 and 5 minutes ATR and then returned to basal values at 20 minutes ATR (p<0.05). In reference to the prevention of lipid peroxidation in tourniquet-induced ischemia-reperfusion injury, the results from the two groups in our study showed that dexmedetomidine did not have an additional protective role during routine general anesthesia.

The effects of nitrous oxide on controlled hypotension during low flow anesthesia.

BACKGROUND AND OBJECTIVES: We investigated the effect of Nitrous Oxide (N2O) on controlled hypotension in low-flow isoflurane-dexmedetomidine anesthesia in terms of hemodynamics, anesthetic consumption, and costs. METHODS: We allocated forty patients randomly into two equal groups. We then maintained dexmedetomidine infusion (0.1 µg.kg-1.min-1) for 10 minutes. Next, we continued it until the last 30 minutes of the operation at a dose of 0.7 µg.kg(-1).hour(-1). We administered thiopental (4-6 mg. kg(-1)) and 0.08-0.12 mg.kg(-1) vecuronium bromide at induction for both groups. We used isoflurane (2%) for anesthesia maintenance. Group N received a 50% O2-N2O mixture and Group A received 50% O -air mixture as carrier gas. We started low-flow anesthesia (1 L.min(-1)) after a 10-minute period of initial high flow (4.4 L.min(-1)). We recorded values for blood pressure, heart rate, peripheral O2 saturation, inspiratory isoflurane, expiratory isoflurane, inspiratory O2, expiratory O2, inspiratory N2O, expiratory N2O, inspiratory CO2, CO2 concentration after expiration, Minimum Alveolar Concentration. In addition, we determined the total consumption rate of fentanyl, dexmedetomidine and isoflurane as well as bleeding. RESULTS: In each group the heart rate decreased after dexmedetomidine loading. After intubation, values were higher for Group A at one, three, five, 10, and 15 minutes. After intubation, the patients reached desired hypotension values at minute five for Group N and at minute 20 for group A. MAC values were higher for Group N at minute one, three, five, 10, and 15 (p < 0.05). FiO2 values were high between minute five and 60 for Group A, while at minute 90 Group N values were higher (p < 0.05). Fi Iso (inspiratuvar isofluran) values were lower in Group N at minute 15 and 30 (p < 0.05). CONCLUSION: By using dexmedetomidine instead of nitrous oxide in low flow isoflurane anesthesia, we attained desired MAP levels, sufficient anesthesia depth, hemodynamic stability and safe inspiration parameters. Dexmedetomidine infusion with medical air-oxygen as a carrier gas represents an alternative anesthetic technique.

Postoperative analgesic effects of wound infiltration with tramadol and levobupivacaine in lumbar disk surgeries.

BACKGROUND: Wound infiltration with local anesthetics may improve postoperative analgesia. Tramadol has been shown to have effects similar to those of local anesthetics. The purpose of this study was to investigate the effects of wound infiltration with levobupivacaine and tramadol on postoperative analgesia for lumbar discectomies. METHODS: Eighty adult patients who were scheduled to undergo elective lumbar discectomy operations were included in the study. Patients were randomly allocated to 4 groups: wound infiltration with 100 mg levobupivacaine (group L), 2 mg/kg tramadol (group T), 2 mg/kg tramadol plus 100 mg levobupivacaine (group LT), and saline (group C). Pain scores with the visual analog scale, patient-controlled analgesic consumption (pethidine), time to first analgesic treatment, and side effects were assessed during the postoperative period. RESULTS: The time to first analgesia was earliest in group C (11.3±2.2 min), followed by group L (163.0±216.3 min) and group T (803.2±268.4 min) (P<0.001). None of the patients in group LT required postoperative analgesic supplementation, and the visual analog scale scores were <3 at all measurement times (P<0.05). Postoperative opioid consumption was 196.0±71.6 mg in group C, 129.0±78.3 mg in group L, and 37.0±35.4 mg in group T (P<0.001). The incidence of side effects was lower in group LT than in the other groups. CONCLUSIONS: Wound infiltration with combined levobupivacaine and tramadol resulted in elimination of postoperative analgesic demand and reduction in the incidence of side effects. We conclude that infiltration of the wound site with combined levobupivacaine and tramadol provides significantly better analgesia compared with levobupivacaine or tramadol alone.

Possible heart failure associated with pregabalin use: case report.

Pregabalin and gabapentin are widely used analgesic, anticonvulsant and anxiolytic agents as they are relatively reliable and easily tolerated. However, they may cause some side effects such as dizziness, somnolence, dose-dependent peripheral edema, and weight gain, which may cause patients to abandon their use. Furthermore, there are a few reports in the literature addressing elderly patients with serious chronic disease and cardiac history, who develop heart failure during pregabalin application. In this report, we present a patient with no cardiac history treated with 300 mg/kg pregabalin due to neuropathic pain, who developed peripheral and then central edema, which were determined after advanced investigations. After stopping pregabalin, the situation regressed. Then, peripheral edema developed associated with the recommended dose of gabapentin, which was used in place of pregabalin. Despite the lack of any published evidence, the New York Heart Association issued a warning about using caution when prescribing pregabalin to type III-IV heart failure patients. Though the effect mechanisms of pregabalin and gabapentin are not well known, the calcium channel relationship may lead to these side effects. In summary, we believe that pregabalin and gabapentin, which is mostly used nowadays, should be administered with care not only in patients with advanced cardiac pathology but also in all patients, due to the potential side effects.

Effects of acute carbon monoxide poisoning on the P-wave and QT interval dispersions.

OBJECTIVE: The aim of our study was to investigate atrial conduction and ventricular repolarization inhomogeneities using P-wave dispersion (Pwd) and QT dispersion (QTd) analyses in acute carbon monoxide (CO) poisoning. METHODS: Sixty patients were retrospectively included in this case-controlled study. Thirty acute CO poisoning patients were assigned to the Group with acute CO poisoning (ACOP). Patients who did not have acute CO poisoning were assigned to the control group (Group C, n=30). Anthropometric measurement, body mass index, electrocardiogram (ECG) and serum electrolyte levels were recorded in all patients. Also, carboxyhemoglobin (COHb) levels were recorded in Group ACOP. Pwd, QT interval and QTd durations were measured. Corrected QT (QTc) and QTc dispersion (QTcd) intervals were determined with the Bazett formula. Independent samples t and Chi-square tests were used for statistical analysis. RESULTS: No statistically significant difference was found between the age, gender distribution, anthropometric measurement, serum electrolytes, PR and QT durations between the groups. The Pwd (56.33 ± 17.11 msec vs 28.33 ± 11.16 msec, p=0.001) and QTd (63.33 ± 26.69 msec vs 42.16 ± 7.84 msec, p=0.001) were significantly longer in Group ACOP than in Group C. In addition, QTc and QTcd durations of Group ACOP were also found to be significantly longer than in Group C (p=0.001). CONCLUSION: In our study, we found in ECG analyses of patients with acute CO poisoning that the Pwd, QTc and QTcd durations were significantly prolonged when compared with control group. For this reason, patients with acute CO poisoning need close attention because of arrhythmias, which can be related to increased QTcd and Pwd durations.

Preoperative abnormal P and QTc dispersion intervals in patients with metabolic syndrome.

We evaluated P wave dispersion (Pwd), QT, corrected QT (QTc), QT dispersion, and corrected QT dispersion (QTcd) intervals in patients with metabolic syndrome (MetS). Patients scheduled to undergo elective noncardiac surgery were included in the study. The main diagnoses, anthropometric measurements, waist circumferences, body mass index, electrocardiograms, serum levels of electrolytes, glucose, and lipids were recorded for all patients. QTc, QTcd intervals were determined with the Bazett formula. MetS (group M, n = 36) was diagnosed using the Adult Treatment Panel III. Controls (group C, n = 40) were chosen on the basis of patients with no MetS and matched for age and gender. There were no differences between groups in terms of age, sex, or serum electrolyte levels (P > 0.05). Waist circumferences, body mass index, serum glucose, and triglyceride values in group M were significantly higher than those in group C (P < 0.001). In group M, Pwd, QTc, QT dispersion and QTcd intervals were significantly longer than those in group C (P < 0.001). This finding and our retrospective analysis suggest that these patients may be at greater risk of perioperative arrhythmias.

Anesthesia induction with sevoflurane and propofol: evaluation of P-wave dispersion, QT and corrected QT intervals.

The present study compared the effects of anesthesia induction with sevoflurane and propofol on hemodynamics, P-wave dispersion (Pwd), QT interval and corrected QT (QTc) interval. A total of 72 adult patients were included in this prospective study. All patients had control electrocardiograms (ECGs) before anesthesia induction. Anesthesia was induced with sevoflurane inhalation or intravenous propofol. Electrocardiography for all patients was performed during the 1(st) and 3(rd) minutes of induction, 3 minutes after administration of muscle relaxant, and at 5 minutes and 10 minutes after intubation. Pwd and QT intervals were measured on all ECGs. QTc intervals were determined using the Bazett formula. There was no significant difference in Pwd and QT and QTc intervals on control ECGs. In the sevoflurane group, except for control ECGs, Pwd and QTc interval on all ECGs were significantly longer than those in the propofol group (p < 0.05). We conclude that propofol should be used for anesthesia induction in patients with a predisposition to preoperative arrhythmias, and in those whose Pwd and QTc durations are prolonged on preoperative ECGs.

Effect of low-flow anesthesia education on knowledge, attitude and behavior of the anesthesia team.

The aim of this study was to evaluate the effect of education on the knowledge, attitude and behavior of anesthesiology staff and residents towards low-flow anesthesia. The staff and residents in the Department of Anesthesia and Reanimation, Zonguldak Karaelmas University were given theoretical and practical training in delivering low-flow anesthesia. To evaluate their attitudes and behaviors toward low-flow anesthesia, we collected data during the 6 months before training, during the first 3 months after training, and at 4-6 months after training. Anesthesia follow-up records, operation time, volatile anesthetic agent used, and the amount (in liters) of fresh gas low mid-anesthesia were recorded in all three stages. A total of 3,158 patients received general anesthesia and inhalation anesthesia was used in 3,115 of these patients. Our study group consisted of 2,752 patients who had no absolute or relative contraindications to low-flow anesthesia. While the mean fresh gas flow was 4.00 +/- 0.00 L/min before training, this level dropped to 2.98 L/min in the first 3 months after training, and to 3.26 L/min in the following 3 months. The mean fresh gas flow was significantly lower at the two post-training assessments than before training (p < 0.05). In conclusion, low-flow anesthesia may be used more frequently if educational seminars are provided to anesthetists. The use of low-flow anesthesia may increase further by allocating more time to this technique in anesthesia training programs provided at regular intervals.

Brief report: the effects of the menstrual cycle on the hemodynamic response to laryngoscopy and tracheal intubation.

We designed this study to determine the effect of the menstrual cycle on the hemodynamic response to tracheal intubation (TI). Sixty-two ASA I women who were either in the follicular phase (group F, n = 31) or luteal phase (group L, n = 31) of their menstrual cycle were included in the study. Patients received propofol and rocuronium for intubation. Hemodynamic variables were recorded before administration of the IV anesthetic, as well as after TI. Rate pressure products were calculated. Groups were similar in terms of demographic data. Rate pressure products values at the first minute after TI were significantly increased in group L than were those in group F (P < 0.001). We conclude that the phase of the menstrual cycle is an important factor in the hemodynamic response to TI.

Effects of fentanyl-lidocaine-propofol and dexmedetomidine-lidocaine-propofol on tracheal intubation without use of muscle relaxants.

The aim of this study was to compare the effects of fentanyl or dexmedetomidine when used in combination with propofol and lidocaine for tracheal intubation without using muscle relaxants. Sixty patients with American Society of Anesthesiologists stage I risk were randomized to receive 1 mg/kg dexmedetomidine (Group D, n = 30) or 2 mg/kg fentanyl (Group F, n = 30), both in combination with 1.5 mg/kg lidocaine and 3 mg/kg propofol. The requirement for intubation was determined based on mask ventilation capability, jaw motility, position of the vocal cords and the patient's response to intubation and inflation of the endotracheal tube cuff. Systolic arterial pressure, mean arterial pressure, heart rate and peripheral oxygen saturation values were also recorded. Rate pressure products were calculated. Jaw relaxation, position of the vocal cords and patient's response to intubation and inflation of the endotracheal tube cuff were significantly better in Group D than in Group F (p < 0.05). The intubation conditions were significantly more satisfactory in Group D than in Group F (p = 0.01). Heart rate was significantly lower in Group D than in Group F after the administration of the study drugs and intubation (p < 0.05). Mean arterial pressure was significantly lower in Group F than in Group D after propofol injection and at 3 and 5 minutes after intubation (p < 0.05). After intubation, the rate pressure product values were significantly lower in Group D than in Group F (p < 0.05). We conclude that endotracheal intubation was better with the dexmedetomidine-lidocaine-propofol combination than with the fentanyl-lidocaine-propofol combination. However, side effects such as bradycardia should be considered when using dexmedetomidine.

Effect of menstrual cycle on the injection pain due to propofol.

BACKGROUND: This prospective, double-blind and randomized study is designed to determine the effect of menstrual cycle on the injection pain of propofol. METHODS: Seventy-two patients scheduled for elective surgery under general anaesthesia were divided into two groups according to the phase of the menstrual cycle. Patients were at follicular phase (Pd 8-12) in Group F (n = 36) and luteal phase (Pd 20-24) in Group L (n = 36). Injection pain was evaluated with 10-point numeric rating scale after 25% of the total propofol dose was injected over 20 s. RESULTS: There were no significant differences in terms of patient characteristics (P > 0.05). The mean propofol pain score was found 1.81 +/- 2.30 in Group F and 4.83 +/- 3.09 in Group L. Group L was found to have higher propofol injection pain scores than Group F (P < 0.001). CONCLUSION: We conclude that the menstrual phase changes the perception of pain due to propofol injection, which is higher in the lutheal phase. In clinical practice, the phases of the menstrual cycle may have a significant role on injection pain of propofol in woman.

Effects of dexmedetomidine pretreatment on bupivacaine cardiotoxicity in rats.

BACKGROUND AND OBJECTIVE: We evaluated the effects of dexmedetomidine pretreatment on bupivacaine cardiotoxicity in anesthetized rats. METHODS: Sixteen Wistar-Albino male rats (300-400 g) were anesthetized with ketamine. Electrocardiographic and invasive blood pressure monitoring were performed, and the results were continuously recorded. The rats were randomized into 2 groups. In group D, rats were pretreated with intravenous dexmedetomidine at a dose of 10 Kg/kg (n = 8), whereas in group S, rats were pretreated with intravenous saline (n = 8). Fifteen minutes later, bupivacaine was infused at a rate of 3 mg/kg per minute until cardiac asystole occurred. The timing of specific cardiotoxic events (a 25%, 50%, and 75% reductions of mean arterial pressure and heart rate as well as occurrence of the first arrhythmia and asystole) was recorded. RESULTS: Dexmedetomidine pretreatment reduced the heart rates and mean arterial pressures of the rats who received it (P G 0.05). Dexmedetomidine pretreatment before bupivacaine administration also significantly increased the time to the 25%, 50%, and 75% reductions in mean arterial pressure and the time to the 25% and 50% reductions in heart rate (P G 0.05). In addition, dexmedetomidine significantly increased the time to first arrhythmia and time to asystole (P G 0.05) in the rats who received it before receiving bupivacaine. CONCLUSIONS: Dexmedetomidine pretreatment delays the effects of bupivacaine cardiotoxicity.

Anesthesia for laparoscopic cholecystectomy: comparative evaluation--desflurane/sevoflurane vs. propofol.

Laparoscopic techniques, have rapidly increased in popularity because of its various benefits. They are widely used in day-case surgical operations and are extensively published. However, postoperative nausea vomiting (PONV) is a commonly observed phenomenon after laparoscopic procedures. Its occurrence may increase depending on the anesthetic techniques used. Despite the fact that the use of propofol and the new low solubility inhalation anesthetics, lead to faster induction and recovery, their effects on PONV is not sufficiently known. Therefore, the aim of this study is to compare the effects of various anesthetic drugs on recovery characteristics and PONV. Following informed consent, 300 ASA I-III patients scheduled for laparoscopic cholecystectomy were investigated. Anesthesia was induced by 1.5 microgkg(-1) fentanyl, 0.03 mgkg(-1) midazolam, 1.5 mgkg(-1) propofol and 0.01 mgkg(-1) vecuronium for all patients. Anesthesia was maintained with desflurane in group D (n = 100), sevoflurane in group S (n = 100) and propofol infusion in group P (n = 100), beside 50% N20/O2 ventilation. All patients were given 4 mg ondansetron and 8 mg dexamethazone iv for preventing PONV, ten minutes before the end of surgery. At the end of the operation, times for extubation, eye opening, orientation, sitting and walking, and the need of ondansetrone in post anesthetic care unit, were recorded. Also, PONV was observed and recorded as early period (first 4 hours) and late period (4-24 hours). Extubation and eye opening times were meaningfully lower in group D. However, no significant differences were observed in orientation, sitting and walking times and PONV among the three groups. All patients who had PONV were women. A correlation was found between PONV and body weight. Even though there were no statistically significant differences among the groups regarding PONV, the number of patients who had PONV in group P was lower. Early recovery time was shortest in group D, while delayed recovery time had no differences. It may be said that these anesthetic drugs have no statistically significant difference for PONV and delayed recovery.