Protective effect of dexmedetomidine in a rat model of α-naphthylthiourea-induced acute lung injury.

BACKGROUND: We assessed the effects of dexmedetomidine in a rat model of α-naphthylthiourea (ANTU)-induced acute lung injury. METHODS: Forty Wistar Albino male rats weighing 200-240 g were divided into 5 groups (n = 8 each), including a control group. Thus, there were one ANTU group and three dexmedetomidine groups (10-, 50-, and 100-µg/kg treatment groups), plus a control group. The control group provided the normal base values. The rats in the ANTU group were given 10 mg/kg of ANTU intraperitoneally and the three treatment groups received 10, 50, or 100 µg/kg of dexmedetomidine intraperitoneally 30 min before ANTU application. The rat body weight (BW), pleural effusion (PE), and lung weight (LW) of each group were measured 4 h after ANTU administration. The histopathologic changes were evaluated using hematoxylin-eosin staining. RESULTS: The mean PE, LW, LW/BW, and PE/BW measurements in the ANTU group were significantly greater than in the control groups and all dexmedetomidine treatment groups (P < 0.05). There were also significant decreases in the mean PE, LW, LW/BW and PE/BW values in the dexmedetomidine 50-µg/kg group compared with those in the ANTU group (P < 0.01). The inflammation, hemorrhage, and edema scores in the ANTU group were significantly greater than those in the control or dexmedetomidine 50-µg/kg group (P < 0.01). CONCLUSION: Dexmedetomidine treatment has demonstrated a potential benefit by preventing ANTU-induced acute lung injury in an experimental rat model. Dexmedetomidine could have a potential protective effect on acute lung injury in intensive care patients.

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.

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.

Effect of dexmedetomidine on testicular torsion/detorsion damage in rats.

BACKGROUND AND OBJECTIVE: We assessed the antioxidant activity of dexmedetomidine (DEX) during an ischemic period in a rat model of testicular torsion/detorsion (T/DT) by using biochemical and histopathological methods. METHODS: Wistar Albino male rats weighing 250-300 g were divided into three groups: sham (group S, n = 7); torsion/detorsion (group T/DT, n = 7), and DEX treatment (group DEX, n = 7). In the T/DT group, right testes were rotated 720 degrees for 1 h. Group S served for normal basal values. Rats in group T/DT were operated to make T/DT, this group served as a control group. Group DEX received intraperitoneal DEX 10 microg . kg(-1) after the 30-min torsion period. For measurement of total antioxidant enzyme activities and malondialdehyde (MDA) levels, testes of 7 animals in each group were excised after 4 h of reperfusion. Germ cell apoptosis was evaluated using the apoptosis protease-activating factor 1 (APAF-1) antibody in all groups and also on the expressions of endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) were assessed within the bilateral testes. RESULTS: Mean MDA levels in group T/DT were significantly higher than in groups S and DEX (p < 0.05). There were also significant decreases in mean total antioxidant activities in group T/DT when compared to groups S and DEX (p < 0.05). These values were significantly higher in group DEX than group T/DT. Germ cell apoptosis, eNOS and iNOS levels were significantly higher in group T/DT when compared to groups S and DEX (p < 0.05). CONCLUSIONS: DEX treatment has potential biochemical and histopathological benefits by preventing ischemia/reperfusion-related cellular damage in an experimental testicular torsion model. Preference of DEX for anesthesia during the detorsion procedure may attenuate ischemia-reperfusion injury.

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.

Anaesthesiology and Reanimation Education in Turkey: Residents' Views.

OBJECTIVE: This study aimed to determine opinions of medical residents undergoing anaesthesia and reanimation training about equipment, programmes, applications, study conditions and shift systems at training institutions in Turkey. METHODS: A web-based survey was sent by e-mail to residents in anaesthesiology and reanimation training programmes. The survey comprised 73 questions about demographic characteristics, satisfaction, basic specialisation knowledge, anxiety and motivation. RESULTS: The study included 270 individuals. Of the residents, 82.2% willingly chose their field, whereas 66.7% stated that specialisation was necessary because of incorrect application of first-stage and GP medical services. The mean of the weekly working hours was 91.69±36.69 hours; the mean number of monthly on-call shifts was 7.49±1.99. Of the participants, 61.9% found the predicted five-year training duration long. The intensive care training duration was sufficient for 71.1% and only 26.3% found the pain management training duration sufficient. CONCLUSION: According to the results, the number of residents is insufficient, workload is heavy, working hours are long and large numbers of shifts are worked without leave afterwards. In spite of negatives and high dissatisfaction, most residents willingly chose their departments and would choose the same branches again. Participants stated that their institutions emphasised service rather than education and research, and educators were less accessible to residents due to increasing service loads.

Morbidity and mortality predictivity of nutritional assessment tools in the postoperative care unit.

The aim was to evaluate the nutritional situation of patients admitted to the Postoperative Acute Care Unit using classic methods of objective anthropometry, systemic evaluation methods, and Nutrition Risk in Critically Ill (NUTRIC) score, and to compare them as a predictor of morbidity and mortality.At admission to the postoperative care unit, patients undergoing various surgeries were assessed for the following items: Subjective Global Assessment (SGA), Nutritional Risk Index (NRI), Nutritional Risk Screening (NRS)-2002, Mini Nutritional Assessment (MNA), Charlson comorbidity index (CCI), and NUTRIC score, anthropometric measurements, serum total protein, serum albumin, and lymphocyte count. Patients were monitored for postoperative complications until death or discharge. Correlation of complications with these parameters was also analyzed.A total of 152 patients were included in the study. In this study a positive correlation was determined between mortality and NRS-2002, SGA, CCI, Acute Physiology and Chronic Health Evaluation , Sepsis-related Organ Failure Assessment, and NUTRIC score, whereas a negative correlation was determined between mortality and NRI. There was a correlation between NUTRIC score and pneumonia, development of atrial fibrillation, delirium, renal failure, inotrope use, and duration of mechanical ventilation. In our study group of postoperative patients, MNA had no predictive properties for any complication, whereas SGA had no predictive properties for any complications other than duration of hospital stay and mortality.The NUTRIC score is an important indicator of mortality and morbidity in postoperative surgical patients. NRI correlated with many postoperative complications, and though SGA and NRS were correlated with mortality, they were not correlated with the majority of complications. MNA was determined not to have any correlation with any complication, mortality, and duration of hospital stay in our patient group.

Effectiveness of sugammadex for cerebral ischemia/reperfusion injury.

Cerebral ischemia may cause permanent brain damage and behavioral dysfunction. The efficacy and mechanisms of pharmacological treatments administered immediately after cerebral damage are not fully known. Sugammadex is a licensed medication. As other cyclodextrins have not passed the necessary phase tests, trade preparations are not available, whereas sugammadex is frequently used in clinical anesthetic practice. Previous studies have not clearly described the effects of the cyclodextrin family on cerebral ischemia/reperfusion (I/R) damage. The aim of this study was to determine whether sugammadex had a neuroprotective effect against transient global cerebral ischemia. Animals were assigned to control, sham-operated, S 16 and S 100 groups. Transient global cerebral ischemia was induced by 10-minute occlusion of the bilateral common carotid artery, followed by 24-hour reperfusion. At the end of the experiment, neurological behavior scoring was performed on the rats, followed by evaluation of histomorphological and biochemical measurements. Sugammadex 16 mg/kg and 100 mg/kg improved neurological outcome, which was associated with reductions in both histological and neurological scores. The hippocampus TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) and caspase results in the S 16 and S 100 treatment groups were significantly lower than those of the I/R group. Neurological scores in the treated groups were significantly higher than those of the I/R group. The study showed that treatment with 16 mg/kg and 100 mg/kg sugammadex had a neuroprotective effect in a transient global cerebral I/R rat model. However, 100 mg/kg sugammadex was more neuroprotective in rats.

[Effects of smoking on venous cannulation pain: a randomized prospective trial]. / Efeitos do tabagismo sobre a dor durante o cateterismo venoso: um estudo prospectivo e randomizado.

BACKGROUND AND OBJECTIVES: It has been demonstrated that smoking increases pain perception; however the effect of smoking on perception of pain during venous cannulation is not known. The purpose of this study is to determine whether or not smoking has an effect on pain perception due to peripheral venous cannulation. METHODS: 220 patients scheduled to have elective surgery were enrolled in the study and were divided into two groups (Group S and C, n=110 for each) according to their smoking habits. Numerical rating scale was introduced to the patients and then peripheral venous cannulation at the dorsum of the hand was made with a 20G intracath. Pain perception of the patients was scored by subsequent numerical rating scale questioning. RESULTS: The demographic characteristics of the groups were identical. Numerical rating scale scores in Group S and C were 3.31±1.56 and 1.65±1.23, respectively (p<0.001). CONCLUSION: Pain perception due to peripheral venous cannulation is higher in smokers. Future studies on pain treatment should consider the smoking habits of patients.

[An evaluation of the psychosocial characteristics of patients admitted to a pain clinic and their relatives]. / Agri poliklinigine basvuran hastalarin ve yakinlarinin psikososyal özelliklerinin degerlendirilmesi.

OBJECTIVES: This study tested the hypothesis that as pain brings about psychosocial changes in the pain patient, it also does in those relatives dealing with and supporting the patient. In order to test the hypothesis, comparisons of psychosocial status were made among patients with chronic pain, their relatives, and a control group (individuals having no pain and no relative with a pain disorder). METHODS: The study included 270 individuals separated into 3 groups: Patients admitted to the Pain Polyclinic at Dokuz Eylül University Faculty of Medicine with chronic pain (Group CP; n=77), relatives of these patients (Group R; n=98), and individuals age- and sex-matched to the relatives as a control group (Group C; n=95). The demographic values of all individuals were recorded, and psychological evaluations performed on all participants using the SCL 90 test. RESULTS: Somatization, anxiety, depression, interindividual sensibility, psychosis, paranoia, anger and general symptom index average scores were found to be high in Group R compared to Group C. CONCLUSION: Changes in psychosocial status were observed in pain patients and their relatives when compared to the control group. The study recommends that in addition to evaluating the psychological status of pain patients in order to provide them with psychological and medical support, relatives of these patients should also be evaluated carefully and given psychological and medical support to enable necessary diagnosis and treatment.

[Rectal dexmedetomidine in rats: evaluation of sedative and mucosal effects]. / Dexmedetomidina retal em ratos: avaliação dos efeitos sedativos e sobre a mucosa.

BACKGROUND AND OBJECTIVES: In this study, we investigated the anesthetic and mucosal effects of the rectal application of dexmedetomidine to rats. METHODS: Male Wistar albino rats weighing 250-300g were divided into four groups: Group S (n=8) was a sham group that served as a baseline for the normal basal values; Group C (n=8) consisted of rats that received the rectal application of saline alone; Group IPDex (n=8) included rats that received the intraperitoneal application of dexmedetomidine (100µgkg(-1)); and Group RecDex (n=8) included rats that received the rectal application of dexmedetomidine (100µgkg(-1)). For the rectal drug administration, we used 22G intravenous cannulas with the stylets removed. We administered the drugs by advancing the cannula 1cm into the rectum, and the rectal administration volume was 1mL for all the rats. The latency and anesthesia time (min) were measured. Two hours after rectal administration, 75mgkg(-1) ketamine was administered for intraperitoneal anesthesia in all the groups, followed by the removal of the rats' rectums to a distal distance of 3cm via an abdominoperineal surgical procedure. We histopathologically examined and scored the rectums. RESULTS: Anesthesia was achieved in all the rats in the Group RecDex following the administration of dexmedetomidine. The onset of anesthesia in the Group RecDex was significantly later and of a shorter duration than in the Group IPDEx (p<0.05). In the Group RecDex, the administration of dexmedetomidine induced mild-moderate losses of mucosal architecture in the colon and rectum, 2h after rectal inoculation. CONCLUSION: Although 100µgkg(-1) dexmedetomidine administered rectally to rats achieved a significantly longer duration of anesthesia compared with the rectal administration of saline, our histopathological evaluations showed that the rectal administration of 100µgkg(-1) dexmedetomidine led to mild-moderate damage to the mucosal structure of the rectum.

[Effects of various anesthesia maintenance on serum levels of selenium, copper, zinc, iron and antioxidant capacity]. / Efeitos da manutenção de várias anestesias sobre os níveis séricos de selênio, cobre, zinco e ferro e a capacidade antioxidante.

BACKGROUND AND OBJECTIVES: In this study, we aimed to investigate the effects of sevoflurane, desflurane and propofol maintenances on serum levels of selenium, copper, zinc, iron, malondialdehyde, and glutathion peroxidase measurements, and antioxidant capacity. METHODS: 60 patients scheduled for unilateral lower extremity surgery which would be performed with tourniquet under general anesthesia were divided into three groups. Blood samples were collected to determine the baseline serum levels of selenium, copper, zinc, iron, malondialdehyde and glutathion peroxidase. Anesthesia was induced using 2-2.5mgkg(-1) propofol, 1mgkg(-1) lidocaine and 0.6mgkg(-1) rocuronium. In the maintenance of anesthesia, under carrier gas of 50:50% O2:N2O 4Lmin(-1), 1 MAC sevoflorane was administered to Group S and 1 MAC desflurane to Group D; and under carrier gas of 50:50% O2:air 4Lmin(-1) 6mgkgh(-1) propofol and 1µgkgh(-1) fentanyl infusion were administered to Group P. At postoperative blood specimens were collected again. RESULTS: It was observed that only in Group S and P, levels of MDA decreased at postoperative 48th hour; levels of glutathion peroxidase increased in comparison to the baseline values. Selenium levels decreased in Group S and Group P, zinc levels decreased in Group P, and iron levels decreased in all three groups, and copper levels did not change in any groups in the postoperative period. CONCLUSION: According to the markers of malondialdehyde and glutathion peroxidase, it was concluded that maintenance of general anesthesia using propofol and sevoflurane activated the antioxidant system against oxidative stress and using desflurane had no effects on oxidative stress and antioxidant system.

Efficiency of levobupivacaine and bupivacaine for supraclavicular block: a randomized double-blind comparative study.

BACKGROUND AND OBJECTIVES: Success rate of catheter applications is low in supraclavicular block. Thus, bupivacaine and levobupivacaine become important with their long effect time in single injection practices. In this study, we aimed to compare the effectiveness, side effects and complications of bupivacaine and levobupivacaine in supraclavicular block. METHODS: Sixty patients aged between 20 and 65, with body weight between 50 and 100 kg, in the ASA I-II-III group who were scheduled for hand, forearm and arm surgery using supraclavicular block were randomized into two groups of 30. The patients received 30 ml 0.5% bupivacaine (Group B) or 30 ml 0.5% levobupivacaine (Group L). Motor and sensory blocks were evaluated. Motor and sensory block onset times, total block durations, postoperative pain, amount of postoperative analgesic used and patient satisfaction were recorded. RESULTS: Demographic data, distribution of surgical area and hemodynamic data were similar between the two groups. Surgery, motor and sensory block durations of Group B and L patients did not vary statistically significantly. However, motor and sensory block onset times in Group B were significantly shorter than Group L (p<0.05). The mean time for first postoperative analgesic demand were 16.6 ± 8.0 h in Group B and 14.4 ± 7.3h in Group L (p>0.05). CONCLUSION: 30 ml 0.5% bupivacaine and levobupivacaine provide similar block characteristics for supraclavicular block. Bupivacaine leads to faster motor and sensory block onset compared to levobupivacaine however similar duration of postoperative analgesia.

The effect of levobupivacaine and bupivacaine on QT, corrected QT (Qtc), and P wave dispersions in cesarean section.

BACKGROUND AND OBJECTIVES: In our study we aimed to investigate the effect of bupivacaine and levobupivacaine on QT, corrected QT (QTc), and P wave dispersion durations during spinal anesthesia in cesarean section. METHODS: Sixty parturients scheduled for elective cesarean section in ASA I-II risk groups were included in the study. Baseline electrocardiographic (ECG) records of the patients were obtained in the operation room. Heart rate (HR), non-invasive blood pressure (NIBP), peripheral oxygen saturation (SpO2) and respiration rates (RR) were recorded. Venous cannulation was performed with 18G cannula and fluid preload made with 10 mL.kg(-1). Lactated Ringer solution. After fluid preload, second ECG recordings were taken and the patients were randomly separated into two groups. Group B (n = 30) received 10mg of bupivacaine and Group L (n = 30) received 10mg of levobupivacaine for spinal anesthesia. ECG recordings were repeated at 1, 5 and 10 minutes after spinal block. HR, NIBP, SpO2, RR and sensory block levels were also recorded at the same time intervals. At predetermined time intervals of spinal anesthesia, P wave dispersion (Pwd), QT dispersion (QTd), and QTc dispersion (QTcd) durations were measured from ECG records. QT and QTc durations are calculated with Bazzett formula. RESULTS: There was no difference between two groups according to block levels, hemodynamic parameters, Pwd, QTd, QTc and QTcd durations. CONCLUSION: Bupivacaine and levobupivacaine may be preferred in spinal anesthesia in pregnant patients who have extended Pwd and QTcd preoperatively.

Effect of ghrelin on inflammatory response in lung contusion.

The purpose of this study was to investigate the effects of ghrelin on inflammatory response and tissue damage following trauma-induced acute lung injury. Thirty male wistar albino rats (300-400 g) were randomly assigned into three groups: control group (n = 6), lung contusion plus saline (saline-treated, n = 12), and lung contusion plus ghrelin (ghrelin-treated, n = 12). Saline- or ghrelin-treated traumatic rats were sacrificed at two time points (24 and 72 hours) after lung contusion. Blood was collected for the analysis of serum adenosine deaminase (ADA). Tissue transforming growth factor-beta 1 (TGF-ß1) and matrix metalloproteinase-2 (MMP-2) levels were measured by enzyme-linked immunosorbent assay and histopathological examination was performed on the lung tissue samples. Our results indicated that ghrelin significantly reduced morphologic damages. Serum ADA activities were significantly decreased after lung contusion and this decline started early with ghrelin treatment. TGF-ß1 and MMP-2 levels in lung tissue were elevated at 72 hours after lung contusion and treatment with ghrelin significantly increased TGF-ß1 level and reduced MMP-2 level. In conclusion, our study demonstrates that acute lung injury initiated proinflammatory responses and ghrelin administration showed an anti-inflammatory effect in lung contusion.

The effect of levobupivacaine and bupivacaine on QT, corrected QT (Qtc), and P wave dispersions in cesarean section.

BACKGROUND AND OBJECTIVES: In our study we aimed to investigate the effect of bupivacaine and levobupivacaine on QT, corrected QT (QTc), and P wave dispersion durations during spinal anesthesia in cesarean section. METHODS: Sixty parturients scheduled for elective cesarean section in ASA I-II risk groups were included in the study. Baseline electrocardiographic (ECG) records of the patients were obtained in the operation room. Heart rate (HR), non-invasive blood pressure (NIBP), peripheral oxygen saturation (SpO2) and respiration rates (RR) were recorded. Venous cannulation was performed with 18G cannula and fl uid preload made with 10mL.kg(-1). Lactated Ringer solution. After fl uid preload, second ECG recordings were taken and the patients were randomly separated into two groups. Group B (n=30) received 10mg of bupivacaine and Group L (n=30) received 10mg of levobupivacaine for spinal anesthesia. ECG recordings were repeated at 1, 5 and 10minutes after spinal block. HR, NIBP, SpO2 , RR and sensory block levels were also recorded at the same time intervals. At predetermined time intervals of spinal anesthesia, P wave dispersion (Pwd), QT dispersion (QTd), and QTc dispersion (QTcd) durations were measured from ECG records. QT and QTc durations are calculated with Bazzett formula.

Effects of esmolol, lidocaine and fentanyl on P wave dispersion, QT, QTc intervals and hemodynamic responses to endotracheal intubation during propofol induction: a comparative study.

BACKGROUND AND OBJECTIVES: In our study we aimed to investigate the effect of esmolol, lidocaine and fentanyl on P-wave dispersion (Pwd), QT and corrected QT (QTc) durations and hemodynamic responses to endotracheal intubation during propofol induction. METHODS: A total of eighty adult patients, American Society of Anesthesiologists (ASA) Physical Status I or II aged 18 to 60 years were included in this prospective, randomised, double-blind study. All patients had control electrocardiograms (ECGs) done before anesthesia induction. The patients were randomised into four equal groups. The control group (Group C) received saline 5mL, the esmolol group (Group E) received esmolol 0.5mg.kg(-1), the fentanyl group (Group F) received fentanyl 2µg.kg(-1) and the lidocaine group (Group L) received lidocaine 1.5mg.kg(-1) before anesthesia induction. Anesthesia was induced with intravenous propofol. ECGs for all patients were performed during the 1(st) and 3(rd) minutes of induction, 3minutes after administration of muscle relaxant, and at 5minutes and 10minutes after intubation. Pwd and QT intervals were measured on all ECGs. QTc intervals were determined using the Bazett formula. Heart rate (HR) and mean arterial pressure (MAP) were recorded before and after induction of anesthesia, immediately after intubation, and 1, 3, 5, 7 and 10minutes after intubation. RESULTS: Compared with control, HR significantly increased in Group C, Group L and Group F after intubation. However, in Group E, there was no significant difference in HR values between control and after intubation. Compared with control, MAP significantly increased in Group C and Group L after the intubation. However, in Group E and Group F, there was no significant difference in MAP values between control and after the intubation. Compared with control, Pwd significantly increased in Group C after intubation. In Group L, Group F and Group E, there was no significant difference in Pwd values between control and after the intubation. Compared with control, QTc duration significantly increased in Group C and L after the intubation. In Group F and Group E, there was no significant difference in QTc durations between control and after the intubation. CONCLUSION: We concluded that administration of esmolol before intubation prevents tachycardia and an increase in MAP, Pwd and QTc duration caused by laryngoscopy and tracheal intubation.

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.

Comparison of the effects of bupivacaine, lidocaine, and tramadol infiltration on wound healing in rats.

BACKGROUND AND OBJECTIVES: The aim of this study was to investigate the effects of saline solution, bupivacaine, lidocaine and tramadol infiltration on wound healing in rats. METHOD: Thirty-two male Wistar Albino rats were randomly separated into four groups, receiving 3 mL saline solution in control group (Group C, n=8), 3 mL of 2% lidocaine in lidocaine group (Group L, n=8), 3 mL of 0.5% bupivacaine in bupivacaine group (Group B, n=8), and 3 mL of 5% tramadol in tramadol group (Group T, n=8). Breaking-strength measurements, collagen bundle counting, and histopathologic evaluation were evaluated in the tissue samples taken from the rats. RESULTS: Comparing the control group with the groups where bupivacaine and lidocaine were used for wound infiltration, collagen production was lower, breaking-strength measurements showed reduced resistance while significantly high edema, vascularity, inflammation scores were found (p<0.0125). Between the control and the tramadol group there were no significant differences in collagen production, breaking-strength measurements, and edema, vascularity, inflammation scores (p>0.0125). CONCLUSION: In our study, we found bupivacaine and lidocaine reduced the collagen production, wound breaking strength, and caused significantly high scores for edema, vascularity, and inflammation when compared to the control group. There was no significant difference between the control and the tramadol group. Results of this experimental preliminary study on rats support the idea that tramadol can be used for wound infiltration anesthesia without adverse effect on the surgical healing process. These results need to be verified in humans.

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.