A Randomized, Placebo-Controlled, Double-Blind Study that Evaluates Efficacy of Intravenous Ibuprofen and Acetaminophen for Postoperative Pain Treatment Following Laparoscopic Cholecystectomy Surgery.

BACKGROUND: Ibuprofen is a NSAID that has anti-inflammatory, antipyretic, and analgesic effects. The oral form of the drug has been used safely for a long time and is one of the most preferred NSAIDs. It has been shown that ibuprofen is effective in the treatment of postoperative pain; however, there have not been sufficient studies on ibuprofen. We evaluated and compared the influence of IV forms of ibuprofen and acetaminophen on pain management and opioid consumption on patients undergoing laparoscopic cholecystectomy surgery. METHODS: Patients were stratified into three groups. Group I (group ibuprofen, n = 30) was administered 800 mg of IV ibuprofen; group A (group acetaminophen, n = 30) was administered 1000 mg of IV acetaminophen; and group C (control group, n = 30) was given 100 ml of saline solution. We evaluated opioid consumption and VAS scores postoperatively. RESULTS: Pain scores in group I and group A at all time periods were lower than those in group C (p < 0.05). Group I had significantly lower VAS scores than those in group A at all time periods postoperatively (p < 0.05). Those in group C had significantly higher opioid consumption than the other groups (p < 0.05). Opioid consumption in group I at all time periods postoperatively was significantly lower than those in group A (p < 0.05). Group I had statistically lower rescue medication than the other groups at all time periods. CONCLUSION: Our study suggested that IV ibuprofen resulted in lower pain scores and reduced opioid use compared with acetaminophen postoperatively in the first 24 h in patients undergoing laparoscopic cholecystectomy surgery.

Comparison of the Trendelenburg position versus upper-limb tourniquet on internal jugular vein diameter.

BACKGROUND: Central venous cannulation is a necessary invasive procedure for fluid management, haemodynamic monitoring and vasoactive drug therapy. The right internal jugular vein (RIJV) is the preferred site. Enlargement of the jugular vein area facilitates catheterization and reduces complication rates. Common methods to enlarge the RIJV cross-sectional area are the Trendelenburg position and the Valsalva maneuver. OBJECTIVE: Compare the Trendelenburg position with upper-extremity venous return blockage using the tourniquet technique. DESIGN: Prospective clinical study. SETTING: University hospital. SUBJECTS AND METHODS: Healthy adult volunteers (American Society of Anesthesiologists class I) aged 18-45 years were included in the study. The first measurement was made when the volunteers were in the supine position. The RIJV diameter and cross-sectional area were measured from the apex of the triangle formed by the clavicle and the two ends of the sternocleidomastoid muscle, which is used for the conventional approach. The second measurement was performed in a 20° Trendelenburg position. After the drainage of the veins using an Esbach bandage both arms were cuffed. The third measurement was made when tourniquets were inflated. MAIN OUTCOME MEASURE(S): Hemodynamic measurements and RIJV dimensions. RESULTS: In 65 volunteers the diameter and cross-sectional area of the RIJV were significantly widened in both Trendelenburg and tourniquet measurements compared with the supine position (P < .001 for both measures). Measurements using the upper extremity tourniquet were significantly larger than Trendelenburg measurements (P=.002 and < .001 for cross-sectional area and diameter, respectively). CONCLUSION: Channelling of the upper-extremity venous return to the jugular vein was significantly superior when compared with the Trendelenburg position and the supine position. LIMITATIONS: No catheterization and study limited to healthy volunteers.

Segmental epidural anesthesia for percutaneous kyphoplasty:comparison with general anesthesia.

BACKGROUND/AIM: This is a feasibility study evaluating whether segmental epidural anesthesia is an alternative anesthetic approach to general anesthesia for percutaneous kyphoplasty. MATERIALS AND METHODS: After ethics committee approval was obtained, 52 ASA class I-III patients scheduled for elective, single-level percutaneous kyphoplasty were recruited. The patients were divided into two equal groups. In Group E (Group Epidural) segmental epidural anesthesia was performed using the loss of resistance technique with saline. In Group G (Group Control) general anesthesia was performed. Hemodynamic parameters, intraoperative and postoperative analgesic requirements, visual analogue scale (VAS) scores, length of stay in the postanesthesia care unit (PACU), and complications were recorded. RESULTS: Hemodynamics were similar between the two groups. Postoperative analgesic requirement was significantly higher in Group G than in Group E (P < 0.004). VAS scores were significantly lower in Group E than in Group G (P < 0.05). Time to first pain experience at the first postoperative 4 h was significantly longer and length of stay in the PACU was significantly shorter in Group E than in Group G (P < 0.001). CONCLUSION: Segmental epidural anesthesia is a safe anesthetic technique for percutaneous kyphoplasty. This technique offered advantages over general anesthesia in terms of postoperative analgesia, analgesic consumption, early recovery, and short PACU stay. Therefore, it should be considered a suitable anesthetic technique in patients undergoing single level percutaneous kyphoplasty.

[Low-dose levobupivacaine plus fentanyl combination for spinal anesthesia in anorectal surgery]. / Combinação de levobupivacaína em dose baixa e fentanil para raquianestesia em cirurgia anorretal.

BACKGROUND: The aim of this study was to investigate the effects of spinal anesthesia using two different doses of fentanyl combined with low-dose levobupivacaine in anorectal surgery. METHODS: In this prospective, double-blind study, 52 American Society of Anaesthesiologists I-II patients scheduled for elective anorectal surgery were randomized into two groups. The patients in group I received intrathecal 2.5mg hyperbaric levobupivacaine plus 12.5µg fentanyl and in group II received intrathecal 2.5mg hyperbaric levobupivacaine plus 25µg fentanyl. All the patients remained in the seated position for 5min after completion of the spinal anesthesia. Sensory block was evaluated with pin-prick test and motor block was evaluated with a modified Bromage scale. RESULTS: Motor block was not observed in both of the groups. The sensory block was limited to the S2 level in group I, and S1 level in group II. None of the patients required additional analgesics during the operation. Time to two-segment regression was shorter in group I compared with group II (p<0.01). One patient in group I and 5 patients in group II had pruritus. Hemodynamic parameters were stable during the operation in both of the groups. CONCLUSION: Spinal saddle block using hyperbaric levobupivacaine with both 12.5µg and 25µg fentanyl provided good quality of anesthesia without motor block for anorectal surgery in the prone position.

Low-dose levobupivacaine plus fentanyl combination for spinal anesthesia in anorectal surgery / Combinação de levobupivacaína em dose baixa e fentanil para raquianestesia em cirurgia anorretal

BACKGROUND: the aim of this study was to investigate the effects of spinal anesthesia using two different doses of fentanyl combined with low-dose levobupivacaine in anorectal surgery. METHODS: in this prospective, double-blind study, 52 American Society of Anaesthesiologists I-II patients scheduled for elective anorectal surgery were randomized into two groups. The patients in group I received intrathecal 2.5 mg hyperbaric levobupivacaine plus 12.5 µg fentanyl and in group II received intrathecal 2.5 mg hyperbaric levobupivacaine plus 25 µg fentanyl. All the patients remained in the seated position for 5 min after completion of the spinal anesthesia. Sensory block was evaluated with pin-prick test and motor block was evaluated with a modified Bromage scale. RESULTS: motor block was not observed in both of the groups. The sensory block was limited to the S2 level in group I, and S1 level in group II. None of the patients required additional analgesics during the operation. Time to two-segment regression was shorter in group I compared with group II (p < 0.01). One patient in group I and 5 patients in group II had pruritus. Hemodynamic parameters were stable during the operation in both of the groups. CONCLUSION: spinal saddle block using hyperbaric levobupivacaine with both 12.5 µg and 25 µg fentanyl provided good quality of anesthesia without motor block for anorectal surgery in the prone position.

JUSTIFICATIVA: O objetivo deste estudo foi investigar os efeitos da raquianestesia com o uso de duas doses diferentes de fentanil em combinação com dose baixa de levobupivacaína em cirurgia anorretal. MÉTODOS: Neste estudo prospectivo e duplo-cego, 52 pacientes com estado físico ASA I-II, programados para cirurgia eletiva anorretal, foram randomicamente alocados em dois grupos. Os pacientes do Grupo I receberam 2,5 mg de levobupivacaína hiperbárica mais 12,5 µg de fentanil por via intratecal e os do Grupo II receberam 2,5 mg de levobupivacaína hiperbárica mais 25 µg de fentanil por via intratecal. Todos permaneceram em posição sentada por cinco minutos após o término da raquianestesia. O bloqueio sensorial foi avaliado com o teste da picada de agulha e o bloqueio motor com a escala modificada de Bromage. RESULTADOS: O bloqueio motor não foi observado em ambos os grupos. O bloqueio sensorial limitou-se ao nível S2 no Grupo I e S1 no Grupo II. Nenhum dos pacientes precisou de analgésico suplementar durante a operação. O tempo de regressão de dois seguimentos foi menor no Grupo I em comparação com o Grupo II (p < 0,01). Um paciente do Grupo I e cinco do Grupo II apresentaram prurido. Os parâmetros hemodinâmicos permaneceram estáveis durante a cirurgia em ambos os grupos. CONCLUSÃO: O bloqueio espinhal em sela com o uso de levobupivacaína hiperbárica, tanto com 12,5 µg quanto com 25 µg de fentanil, proporciona boa qualidade de anestesia sem bloqueio motor para cirurgia anorretal em decúbito ventral.

Low-dose levobupivacaine plus fentanyl combination for spinal anesthesia in anorectal surgery.

BACKGROUND: the aim of this study was to investigate the effects of spinal anesthesia using two different doses of fentanyl combined with low-dose levobupivacaine in anorectal surgery. METHODS: in this prospective, double-blind study, 52 American Society of Anaesthesiologists I-II patients scheduled for elective anorectal surgery were randomized into two groups. The patients in group I received intrathecal 2.5mg hyperbaric levobupivacaine plus 12.5 µg fentanyl and in group II received intrathecal 2.5mg hyperbaric levobupivacaine plus 25 µg fentanyl. All the patients remained in the seated position for 5 min after completion of the spinal anesthesia. Sensory block was evaluated with pin-prick test and motor block was evaluated with a modified Bromage scale. RESULTS: motor block was not observed in both of the groups. The sensory block was limited to the S2 level in group I, and S1 level in group II. None of the patients required additional analgesics during the operation. Time to two-segment regression was shorter in group I compared with group II (p<0.01). One patient in group I and 5 patients in group II had pruritus. Hemodynamic parameters were stable during the operation in both of the groups. CONCLUSION: spinal saddle block using hyperbaric levobupivacaine with both 12.5 µg and 25 µg fentanyl provided good quality of anesthesia without motor block for anorectal surgery in the prone position.

Anesthesia for a child with Walker-Warburg syndrome.

BACKGROUND AND OBJECTIVES: Walker-Warburg Syndrome is a rare, autosomal recessive congenital muscular dystrophy manifested by central nervous system, eye malformations and possible multisystem involvement. The diagnosis is established by the presence of four criteria: congenital muscular dystrophy, type II lissencephaly, cerebellar malformation, and retinal malformation. Most of the syndromic children die in the first three years of life because of respiratory failure, pneumonia, seizures, hyperthermia and ventricular fibrillation. CASE REPORT: The anesthetic management of a two-months-old male child listed for elective ventriculo-peritoneal shunt operation was discussed. CONCLUSIONS: A careful anesthetic management is necessary due to the multisystem involvement. We reported anesthetic management of a two-months-old male child with Walker-Warburg Syndrome who was listed for elective ventriculo-peritoneal shunt operation.

Anestesia em criança com síndrome de Walker-Warburg / Anesthesia for a child with Walker-Warburg syndrome / Anestesia en niño con el síndrome de Walker-Warburg

Justificativa e objetivos: A síndrome de Walker-Warburg é uma distrofia muscular autossômica recessiva congênita rara, manifestada pelo sistema nervoso central com malformações oculares e possível envolvimento de vários sistemas. O diagnóstico é estabelecido pela presença de quatro critérios: distrofia muscular congênita, lisencefalia tipo II, malformação cerebelar e malformação da retina. A maioria das crianças com a síndrome morre nos primeiros três anos de vida por causa de insuficiência respiratória, pneumonia, convulsões, hipertermia e fibrilação ventricular. Relato de caso: É discutida a conduta anestésica em uma criança do sexo masculino, de dois meses, programada para cirurgia eletiva de derivação ventrículo-peritoneal. Conclusões: Uma abordagem anestésica cuidadosa é necessária por causa do envolvimento de vários sistemas. Relatamos a conduta anestésica em uma criança do sexo masculino de dois meses com síndrome de Walker-Warburg, que foi programada para cirurgia eletiva de derivação ventrículo-peritoneal. .

Background and objectives: Walker-Warburg Syndrome is a rare, autosomal recessive congenital muscular dystrophy manifested by central nervous system, eye malformations and possible multisystem involvement. The diagnosis is established by the presence of four criteria: congenital muscular dystrophy, type II lissencephaly, cerebellar malformation, and retinal malformation. Most of the syndromic children die in the first three years of life because of respiratory failure, pneumonia, seizures, hyperthermia and ventricular fibrillation. Case report: The anesthetic management of a two-months-old male child listed for elective ventriculo-peritoneal shunt operation was discussed. Conclusions: A careful anesthetic management is necessary due to the multisystem involvement. We reported anesthetic management of a two-months-old male child with Walker -Warburg Syndrome who was listed for elective ventriculo-peritoneal shunt operation. .

Justificativa y objetivos: el síndrome de Walker-Warburg es una distrofia muscular autosómica recesiva congénita rara, manifestada por el sistema nervioso central con malformaciones oculares y la posible participación de varios sistemas. El diagnóstico se establece por la presencia de 4 criterios: distrofia muscular congénita, lisencefalia tipo II, malformación cerebelar y malformación de la retina. La mayoría de los niños con el síndrome se muere a los primeros 3 años de vida debido a la insuficiencia respiratoria, neumonía, convulsiones, hipertermia y fibrilación ventricular. Relato de caso: se discute aquí la conducta anestésica en un niño del sexo masculino, de 2 meses de edad, programado para la cirugía electiva de derivación ventrículo-peritoneal. Conclusiones: un cuidadoso abordaje anestésico se hace necesario debido a la involucración de varios sistemas. Relatamos la conducta anestésica en un niño del sexo masculino de 2 meses de edad, con el síndrome de Walker-Warburg, que fue programado para la cirugía electiva de derivación ventrículo-peritoneal .

In vitro effect of dexmedetomidine on platelet aggregation.

BACKGROUND AND OBJECTIVES: Dexmedetomidine is a selective α(2)-agonist. There are 250-300 α(2)-adrenoceptor on the surface of each human platelet and ephedrine induces platelet aggregation by binding these receptors. This study was designed to study platelet function after incubation with therapeutic concentrations of dexmedetomidine. METHODS: The study was carried out on 18 healthy, non-smoking males, ages ranging 25 to 35 years old. Because of the recommended therapeutic concentration range of dexmedetomidine obtained by intravenous infusion is 0.4-1.2 ng.mL(-1), dexmedetomidine solutions were prepared in three different concentrations. The calculated value of dexmedetomidine solution and diluent without dexmedetomidine as control were added to the blood sample. Thus, we obtained 0, 0.4, 0.8 and 1.2 ng.mL(-1) dexmedetomidine concentrations of plasma. Each concentration of dexmedetomidine was incubated with whole blood at 37°C during 15 minutes. Then blood samples were centrifugated to prepare platelet-rich plasma and platelet-poor plasma. The platelet-rich plasma was diluted with the platelet-poor plasma to yield test platelet-rich plasma with a fi nal platelet count of 250 ± 50 X 10(9).L(-1). RESULTS: The platelet aggregation amplitudes and slopes were statistically similar among all groups by the aggregation test, which were performed with ADP, collagen or epinephrine. CONCLUSION: Therapeutic concentrations of dexmedetomidine had no effect on the platelet functions in healthy individuals in vitro.

Efeito in vitro de dexmedetomidina na agregação plaquetária / In vitro effect of dexmedetomidine on platelet aggregation / Efecto in vitro de la dexmedetomidina en la agregación plaquetaria

JUSTIFICATIVA E OBJETIVOS: Dexmedetomidina é um α2-agonista seletivo. Há 250-300 receptores α2-adrenérgicos na superfície de cada uma das plaquetas humanas e a efedrina induz a agregação das plaquetas por ligação desses receptores. Este estudo foi desenvolvido para estudar a função plaquetária após incubação com concentrações terapêuticas de dexmedetomidina. MÉTODOS: O estudo foi conduzido com 18 homens saudáveis, não fumantes, com idades entre 25 e 35 anos. Porque o intervalo recomendado de concentração terapêutica de dexmedetomidina, obtido por infusão intravenosa, é de 0,4-1,2 ng.mL-1, as soluções de dexmedetomidina foram preparadas em três concentrações diferentes. Os valores calculados da solução de dexmedetomidina e do diluente sem dexmedetomidina (controle) foram adicionados a uma amostra de sangue. Assim, 0; 0,4; 0,8 e 1,2 ng.mL-1 de concentrações plasmáticas de dexmedetomidina foram obtidas. Cada concentração de dexmedetomidina foi incubada com sangue total a 37ºC durante 15 minutos. Em seguida, as amostras de sangue foram centrifugadas para preparar o plasma rico em plaquetas e o plasma pobre em plaquetas. O plasma rico em plaquetas foi diluído com o plasma pobre em plaquetas para gerar o teste de plasma rico em plaquetas com uma contagem final de plaquetas de 250 ± 50 x 10(9).L-1. RESULTADOS: As amplitudes e os declives da agregação plaquetária foram estatisticamente semelhantes entre todos os grupos nos testes de agregação feitos com ADP, colágeno ou adrenalina. CONCLUSÃO:As concentrações terapêuticas de dexmedetomidina não tiveram efeito in vitro nas funções plaquetárias de indivíduos saudáveis.

BACKGROUND AND OBJECTIVES: Dexmedetomidine is a selective α2-agonist. There are 250-300 α2-adrenoceptor on the surface of each human platelet and ephedrine induces platelet aggregation by binding these receptors. This study was designed to study platelet function after incubation with therapeutic concentrations of dexmedetomidine. METHODS: The study was carried out on 18 healthy, non-smoking males, ages ranging 25 to 35 years old. Because of the recommended therapeutic concentration range of dexmedetomidine obtained by intravenous infusion is 0.4-1.2 ng.mL-1, dexmedetomidine solutions were prepared in three different concentrations. The calculated value of dexmedetomidine solution and diluent without dexmedetomidine as control were added to the blood sample. Thus, we obtained 0, 0.4, 0.8 and 1.2 ng.mL-1 dexmedetomidine concentrations of plasma. Each concentration of dexmedetomidine was incubated with whole blood at 37ºC during 15 minutes. Then blood samples were centrifugated to prepare platelet-rich plasma and platelet-poor plasma. The platelet-rich plasma was diluted with the platelet-poor plasma to yield test platelet-rich plasma with a final platelet count of 250 ± 50 X 10(9).L-1. RESULTS: The platelet aggregation amplitudes and slopes were statistically similar among all groups by the aggregation test, which were performed with ADP, collagen or epinephrine. CONCLUSION: Therapeutic concentrations of dexmedetomidine had no effect on the platelet functions in healthy individuals in vitro.

JUSTIFICATIVA Y OBJETIVOS: La Dexmedetomidina es un α2-agonista selectivo. Hay 250-300 receptores α2-adrenérgicos en la superficie de cada una de las plaquetas humanas y la efedrina induce a la agregación de las plaquetas por el vínculo con esos receptores. Este estudio tuvo el objetivo de estudiar la función plaquetaria después de la incubación con concentraciones terapéuticas de dexmedetomidina. MÉTODOS: El estudio fue llevado a cabo con 18 hombres sanos, no fumadores, con edades entre los 25 y los 35 años. Como el intervalo recomendado de concentración terapéutica de dexmedetomidina obtenido por infusión intravenosa es de 0,4-1,2 ng/mL, las soluciones de dexmedetomidina fueron preparadas en tres concentraciones diferentes. Los valores calculados de la solución de dexmedetomidina y del diluyente sin dexmedetomidina (control), fueron adicionados a una muestra de sangre. Así se obtuvieron 0; 0,4; 0,8 y 1,2 ng.mL-1 de concentraciones plasmáticas de dexmedetomidina. Cada concentración de dexmedetomidina fue incubada con sangre total a 37ºC durante 15 minutos. A continuación se centrifugaron las muestras de sangre para preparar el plasma rico en plaquetas y el plasma pobre en plaquetas. El plasma rico en plaquetas se diluyó con el plasma pobre en plaquetas para generar el test de plasma rico en plaquetas con un conteo final de plaquetas de 250 ± 50 x 10(9).L-1. RESULTADOS: Las amplitudes y los declives de la agregación plaquetaria fueron estadísticamente similares entre todos los grupos en los test de agregación hechos con ADP, colágeno o adrenalina. CONCLUSIÓN: Las concentraciones terapéuticas de dexmedetomidina no tuvieron efecto in vitro en las funciones plaquetarias de individuos sanos.

The effects of midazolam and dexmedetomidine infusion on peri-operative anxiety in regional anesthesia.

BACKGROUND: This study aimed to compare the influences ofmidazolam and dexmedetomidine infusion on anxiety scores in patients undergoing surgery with regional anesthesia. METHODS: Eighty ASA I or II class patient undergoing elective surgery with regional anesthesia were included in the study. Permanent anxiety scores were determined using the State-Trait Anxiety Inventory (STAI)-1 and 2 one day before the surgery. In Group I patients, dexmedetomidine 0.5 micro g/kg basal infusion for 10 min and 0.5 micro g/kg/h for maintenance was administered. In Group II patients, midazolam infusion at a rate of 0.05 mg/kg for 10 min and 0.05 mg/kg/h for maintenance was administered. The sedation scores were determined every 5 min. The steady state anxiety scores of the patients were determined one day before, 30 min after operation, at the end of the operation, and at 30 min and day 7 postoperatively using STAI-1 score. Side effects were determined and recorded. RESULTS: Sedation scores were comparable in both of two treatment groups. Anxiety scores were maintained with drug infusions. The incidences of side effects were significantly decreased in midazolam group compared to the dexmedetomidine group. CONCLUSION: Midazolam infusion was found to be more appropriate and efficient than dexmedetomidine during regional anesthesia practice. Dexmedetomidine infusion should be cautiously used in regional anesthetic techniques performing symphathetic blockade.

Effects of low-dose methotrexate in spinal cord injury in rats.

BACKGROUND: This study was designed to evaluate the possible protective effects of low-dose methotrexate in the spinal cord injury (SCI) in rats. METHODS: Thirty-seven Wistar albino rats were used in the present study. Except for the animals of the Sham group, all animals were divided into two main groups, which were used in acute and subacute stage investigations. Then, thoracal laminectomy was performed, and except for the Sham group, SCI was induced using a temporary aneurysm clip. After clip compression, the experimental material (methotrexate or methylprednisolone) was administered intraperitoneally, except in the Sham and Control groups. Then, the spinal cords were removed to evaluate the SCI histopathologically and biochemically at the scheduled date. RESULTS: Neither experimental material was shown to reduce the histopathological grade in either stage of SCI. Low-dose methotrexate was shown to decrease lipid peroxidation levels only in the subacute stage of SCI. However, methylprednisolone and low-dose methotrexate could not decrease or block myeloperoxidase enzyme activation in either stage of SCI. CONCLUSION: Low-dose methotrexate was effective in reducing the lipid peroxidation levels in the subacute stage of SCI, although histopathological evaluation results and myeloperoxidase levels of all groups did not support this finding at either stage.

Effects of intracisternal and intravenous dexmedetomidine on ischemia-induced brain injury in rat: a comparative study.

AIM: To compare the effect of dexmedetomidine administered by intracisternal route with by intravenous route on brain tissue of rat after incomplete cerebral ischemia. MATERIAL AND METHODS: Cerebral ischemia was produced by the combination of right common carotid artery occlusion and hemorrhagic hypotension during 30 minutes. Thirty minutes before the ischemia, 0.1 ml 0.9% NaCl (Group SIC, n=6) or 9 µg/kg dexmedetomidine (Group DIC, n=6) was administered into the cisterna magna. For the intravenous groups, 9 µg/kg dexmedetomidine (Group DIV, n=6) or 0.9% NaCl (Group CONTROL, n=6) 5 ml/kg/h was given in 2 hours. After 24 hours, the lipid peroxidation levels were measured in the brain tissue and plasma. Hippocampal formations were used for histopathological examination. RESULTS: Intravenous dexmedetomidine produced a decrease in baseline mean arterial blood pressure and plasma glucose concentrations. There was a significant difference between the DIV group and DIC, SIC, CONTROL groups regarding the brain lipid peroxidation levels (p < 0.001, p < 0.001, p=0.001, respectively), and regarding the picnotic neuronal cell count (p < 0.001, p=0.01, p=0.009, respectively). Mean plasma lipid peroxidation levels of the DIV group was different from the DIC group (p=0.003). CONCLUSION: Systemically administered dexmedetomidine had neuroprotective effect in ischemia-induced neuronal damage, but centrally administered dexmedetomidine did not.

Evaluation of the neurotoxicity of the polyethylene glycol hydrogel dural sealant.

AIM: Although polyethylene glycol (PEG) is a neutral, biocompatible hydrophilic polymer recognized for its lack of interaction with biological barrier, its neurotoxicity has not been clearly identified in neurosurgery. This study is constructed to evaluate the possible neurotoxicity of a PEG hydrogel dural sealant. MATERIAL AND METHODS: After a burrhole was opened in the left parietal bone of the twenty five Wistar albino rats, the dura mater and cerebral cortex were incised and the experimental material (activated polyethylene glycol and polyethylene imine) was sprayed into the burrhole. Then brain tissues were harvested for histopathological and biochemical studies at 72 hours to investigate the acute stage changes and on 15th day to evaluate the chronic stage changes. RESULTS: There were statistically significant differences among the groups regarding the comparison of the values of the PMNL cell infiltration grades, gliosis and congestion in both acute and chronic stages. However, the values of the MNL cell infiltration grades, edema and fibrin formation, lipid peroxidation levels of harvested brain tissues were similar in all groups. CONCLUSION: Although this study did not present the detailed histopathological and biochemical evaluation results, it indicated that the application of the PEG-based hydrogel sealant was not associated with neurotoxicity, delayed healing, or degenerative changes.

Effects of intracisternal dexmedetomidine on cerebral neuronal cells in rat: a preliminary study.

AIM: The aim was to investigate whether dexmedetomidine had a toxic effect on cerebral neurons when it was administered centrally into the cerebrospinal fluid by the intracisternal route. MATERIAL AND METHODS: Eighteen rats were anesthetized and the right femoral artery was cannulated. Mean arterial pressures, heart rates, arterial carbon dioxide tension, arterial oxygen tension, and blood pH were recorded. When the free cerebrospinal fluid flow was seen, 0.1 ml normal saline (Group SIC, n=6) or 9 µg/kg diluted dexmedetomidine in 0.1 ml volume (Group DIC, n=6) was administered into the cisterna magna of rats. After 24 hours, the whole body blood was collected for measurement of plasma lipid peroxidation (LPO) levels. The hippocampal formations used for histopathological examination and measurement of tissue LPO levels. RESULTS: There was a statistically significant difference between the DIC/SIC groups and DIC/CONTROL groups regarding the brain LPO levels (p=0.002, p < 0.001, respectively). Plasma LPO levels were statistically different between the CONTROL/DIC groups, CONTROL/SIC groups, DIC/ SIC groups (p=0.002, p=0.047, p=0.025, respectively), The picnotic neuron counts were different between the CONTROL/SIC groups, CONTROL/ DIC groups, DIC/SIC groups (p < 0.001, p=0.001, p=0.024, respectively). CONCLUSION: In conclusion, dexmedetomidine had a toxic effect on cerebral neurons when it was administered centrally into the cerebrospinal fluid by the intracisternal route.

Preoperative exercise heart rate recovery predicts intraoperative hypotension in patients undergoing noncardiac surgery.

STUDY OBJECTIVE: To assess the predictive role of heart rate (HR) recovery in the detection of intraoperative hypotension in patients undergoing noncardiac surgery. DESIGN: Prospective, observational study. SETTING: Department of cardiology and operating rooms of university hospitals. PATIENTS: 160 ASA physical status 1 and 2 patients scheduled for elective noncardiac surgery. MEASUREMENTS: All patients underwent exercise stress testing. Maximum HRs and metabolic equivalent levels were recorded. Heart rate recovery at the first, second, and third minutes were calculated by subtracting HRs one, two, and three minutes into the recovery period from the maximal HR at peak exercise. A decrease in mean arterial pressure (MAP) of greater than 30% was defined as intraoperative hypotension and recorded. Patients were classified to two groups according to whether they had intraoperative hypotension. MAIN RESULTS: Hypotensive episode was observed in 31 patients (19.7%) during the operation. The presence of diabetes mellitus was higher in patients with intraoperative hypotension (22.6% vs 7.1%, P = 0.019). Mean HR recovery at the first, second, and third minutes was significantly lower in the intraoperative hypotension group (P = 0.001, P = 0.004, and P = 0.031, respectively). Heart rate recovery at the first, second, and third minutes was a good predictor of intraoperative hypotension, but only HR recovery at the first minute (OR 0.82, 95% CI 0.73 to 0.92, P = 0.001) and HR recovery at the second minute (OR, 0.90; 95% CI, 0.82 to 0.98; P = 0.019) were independent predictors of intraoperative hypotension. A higher negative correlation was noted between the degree of MAP reduction and HR recovery at the first minute (r = -0.797, P = 0.001). CONCLUSIONS: Abnormal preoperative exercise HR recovery predicts intraoperative hypotension in patients undergoing noncardiac surgery. Given the importance of intraoperative hypotension, preoperative use of exercise testing might be considered.

Comparison of effects of dexmedetomidine-ketamine and dexmedetomidine-midazolam combinations in transurethral procedures.

OBJECTIVE: To compare the effects of dexmedetomidine-ketamine and dexmedetomidine-midazolam combinations on the recovery time, hemodynamic and respiratory variables, and side effects in patients undergoing transurethral procedures. METHODS: Sixty patients scheduled for elective outpatient transurethral procedure were randomized into 2 groups. In the group K, a ketamine-dexmedetomidine combination was administered, and in the group M, midazolam-dexmedetomidine was administered, to provide sedation/analgesia. Pain and sedation levels were assessed using visual analog score (VAS) and Ramsey Sedation Scale, respectively. The recovery time was assessed with the scale of Aldrete. Time was measured and recorded to the moment at which patient responses brought the Aldrete score to 10 points. Time to eye opening and length of stay in the recovery room were recorded. RESULTS: Group M showed significantly lower mean arterial pressure (MAP) values at 5 and 10 minutes during the procedure when compared with group K (P = .02 and P = .01, respectively). Visual analogue scale scores were greater in group M than in group K at 5 and 10 minutes for the transurethral procedure (P = .039 and P = .028, respectively). Sedation scores were similar between groups during the procedure. Time to eye opening and length of recovery room stay were shorter (P < .001 and P < .001, respectively), and Aldrete scores were greater in group K than group M. CONCLUSION: Both combinations provided satisfactory sedation levels, but the dexmedetomidine-ketamine combination provided better analgesia and hemodynamic stability, with less nausea and vomiting and shorter recovery time, than the dexmedetomidine-midazolam combination.

Neuroprotective effects of racemic ketamine and (S)-ketamine on spinal cord injury in rat.

BACKGROUND: The aim of this study was to investigate and to compare the potential neuroprotective effects of racemic ketamine, (S)-ketamine and methylprednisolone after an experimental spinal cord injury model in rats. METHODS: Fifty-nine Wistar albino rats were divided into three main groups as acute stage (A), subacute stage (SA) and sham groups and then acute and subacute stage groups were divided into four groups regarding the used drug as control (CONT), racemic ketamine (RK), (S)-ketamine (SK) and methylprednisolone (MP) groups. A dorsal laminectomy was performed; and spinal cord injury was induced by using a temporary aneurysm clip. Four hours later from the clip compression, except those of the sham and control groups, the drugs (60 mg/kg racemic ketamine, 60 mg/kg (S)-ketamine or 30 mg/kg methylprednisolone) were administered intraperitoneally. At 72th h and 7th days of the study, the spinal cords of rats were removed from T8 level to the conus medullaris level. The specimens were and evaluated histopathologically, tissue lipid peroxidation (LPO) and myeloperoxidation (MPO) levels were measured and biochemically. RESULTS: The histopathological results were similar both in the acute and in the subacute stage groups. There was a statistically significant difference among all groups regarding the tissue LPO levels (p<0.001). There was a statistically significant difference between the CONT-A group and the MP-A, RK-A and SK-A groups (p=0.004, p<0.001 and p=0.007, respectively) in acute stage and between the CONT-SA group and SK-SA group (p=0.002) in subacute stage. There was a statistically significant difference among all groups regarding the tissue MPO levels (p=0.001). The median MPO levels were similar among acute stage groups (p=0.057), but there was a statistical difference among subacute stage groups (p=0.046). CONCLUSION: (S)-ketamine is more effective than methylprednisolone and racemic ketamine to reduce the LPO levels in subacute stage of spinal cord injury in rats. And, it is as effective as methylprednisolone in preventing secondary spinal cord injury histopathologically.

Evaluation of the neurotoxicity of DMSO infused into the carotid artery of rat.

INTRODUCTION: Despite the explanations put forth in many studies regarding histopathological evidence of the inflammatory stage related with the infusion of dimethyl sulfoxide (DMSO) in the vessel wall and its lumen, there has been no research to evaluate its neural toxicity when it is infused via the intracarotid route. This study was designed to evaluate the possible neurotoxic effects of DMSO on the closer and distant brain tissue and carotid artery when it was slowly infused into the internal carotid arteries of the rats. METHODS: The right common carotid artery bifurcation was exposed through a midline neck incision, and then except those of the control group animals (n=5), the experimental material (normal saline, n=5 or anhydrous DMSO, n=10) was infused into the internal carotid artery of the Wistar albino rats. After the experimental materials were administered intra-arterially, brain tissues were harvested for histopathological and biochemical studies at 72 h for investigation of the acute stage changes and on 10th day for investigation of the chronic stage changes. Internal carotid arteries of both sides were also removed for histopathological evaluation. During sacrification of the rats, whole body blood of them are collected for biochemical evaluation. RESULTS: There was no statistically significant difference between the groups regarding comparison of the mean values of the hippocampal neuronal cell counts and the carotid artery diameters in both acute and chronic stages. Also, mean values of the lipid peroxidation levels of harvested brain tissues and serums of the collected bloods were similar in control, saline and DMSO groups. CONCLUSION: This experimental study suggested that DMSO has no toxic effect on the neural and arterial tissues of rats when it is slowly infused into the carotid artery.

The effects of tramadol and levobupivacaine infiltration on postoperative analgesia in functional endoscopic sinus surgery and septorhinoplasty.

OBJECTIVE: The aim of this prospective, randomized, double-blind study was to investigate the postoperative analgesic effects of levobupivacaine or tramadol infiltration administered prior to surgery in septorhinoplasty (SRP) or endoscopic sinus surgery (ESS). MATERIAL AND METHODS: Sixty ASA class I-III adult patients electively undergoing SRP or ESC were included the study. Induction of anesthesia was performed with propofol 2-2.5 mg/kg, rocuronium bromide 0.6 mg/kg and fentanyl 1 µg/kg i.v. Sevoflurane 2% with an N2O/O2 mixture (FiO2: 35%) was used for maintenance. Tramadol 0.5 mg/kg (Group T: n=20), levobupivacaine 0.25% (Group L: n=20) and lidocaine 1% (Group C: n=20) in a 1/200,000 adrenaline solution was infiltrated into the surgical area 10 min before the operation (5 mL for ESS and 10 mL for SRP). All patients received fentanyl (bolus dose: 15 µg and lockout interval: 10 min) with a patient-controlled analgesia device during the postoperative period. Pain was assessed using an 11-point visual analogue scale (VAS) every 4 h for the first 24 h. Analgesic requirements, opioid consumption and side effects in the postoperative period were recorded. RESULTS: There was a statistically significant decrease in postoperative fentanyl demand and consumption in patients receiving tramadol. Fentanyl doses in the 24 h period were 345.2±168.8 µg, 221.1±120.6 µg and 184.1±130.3 µg (p=0.002) for the Groups C, L and T, respectively. There were statistically significant differences in fentanyl requirements between the tramadol and control groups at the 16, 20 and 24 h time points (p=0.012, p=0.004 and p=0.002, respectively). The side effect profiles were similar. CONCLUSIONS: Our study indicates that the preemptive tramadol infiltration technique is an efficient, practical and safe alternative to levobupivacaine in ESS or SRP operations.