Dexmedetomidine as supplement to low-dose levobupivacaine spinal anesthesia for knee arthroscopy

AimTo evaluate efficiency of dexmedetomidine compared to fentanyl as supplements to low-dose levobupivacaine spinal anesthesia in patients undergoing knee arthroscopy.Materials and methodsSixty adult patients (ASA I or II) scheduled for knee arthroscopy were randomized to receive plain levobupivacaine (4 mg) plus dexmedetomidine (3 μg) in group D or fentanyl (10 μg) in group F.ResultsDexmedetomidine shortened time to surgery (P = 0.002), time to highest sensory level (P = 0.001), and time to highest Bromage score (P < 0.001). The highest sensory level was comparable in both groups (P = 0.969), but the duration of sensory block was significantly longer in group D (P = 0.009). The highest Bromage score was 2 in both groups. This score was attained in significant higher number of patients in group D (P = 0.038) that showed better muscular relaxation (P = 0.035). At the end of surgery, a residual motor block (Bromage score 1) was observed in significant higher number of patients (P = 0.033) and time to ambulation was significantly longer in group D (P = 0.001). There was no difference in the number of patients bypassed post-anesthesia care unit (PACU) (P = 0.761) or time to hospital discharge (P = 0.357) between groups. The pain free period was more prolonged (P < 0.001), and the visual analog scale (VAS) for pain was lower at the 2nd, 4th, 6th, and 8th postoperative hours (P < 0.001, <0.001, 0.013, 0.030 respectively) in group D.ConclusionDexmedetomidine is a good alternative to fentanyl for supplementation of low-dose levobupivacaine spinal anesthesia for knee arthroscopy.     

Comparative study of epidural morphine and epidural dexmedetomidine used as adjuvant to levobupivacaine in major abdominal surgery

BackgroundA lot of researches have been done to find an adjuvant in regional anesthesia that inhibits pain without any side effects.AimThis study was conducted to evaluate the onset, extent and duration of sensory and motor block, and side effects of morphine and dexmedetomidine when used as adjuvants to levobupivacaine in epidural anesthesia in major abdominal surgery.Materials and methodsA prospective randomized study was conducted on 60 patients classified as American Society of Anesthesiologists status I and status II who underwent abdominal surgery. Patients were randomly allocated into two groups; group I levobupivacaine morphine group (LM), group II: levobupivacaine dexmedetomidine group (LD), comprising of 30 patients each. Group I patients received 20 ml of 0.5% levobupivacaine (150 mg) and 0.005 % morphine. Group II patients received 20 ml of 0.5% levobupivacaine and 1.5 μg/kg dexmedetomidine. The onset, extent and duration of sensory and motor blocks, abdominal muscle relaxation, and side effects were recorded.ResultsThere were no statistically significant differences between the two groups as regards onset of sensory block or sensory level achieved. Time to reach motor block was shorter in the LM group than the LD group. There were no significant differences between the time of total regression of sensory or motor black and abdominal muscle relaxation. As regards side effects, more patients in the LM group suffered from pruritis and more patients suffered from dry mouth in the LD group.ConclusionDexmedetomidine is a good alternative to morphine as an adjuvant to levobupivacaine in epidural anesthesia in major abdominal surgeries.     

Comparação de fentanil e dexmedetomidina como adjuvante à bupivacaína para raquianestesia unilateral em cirurgia de membros inferiores: estudo randômico

Background and objectivesOne of the disadvantages of unilateral spinal anesthesia is the short duration of post‐operative analgesia, which can be addressed by adding adjuvants to local anesthetics. The aim of current study was to compare the effects of adding dexmedetomidine, fentanyl, or saline to bupivacaine on the properties of unilateral spinal anesthesia in patients undergoing calf surgery.MethodsIn this double‐blind clinical trial, 90 patients who underwent elective calf surgery were randomly divided into three groups. The spinal anesthetic rate in each of the three groups was 1 mL bupivacaine 0.5% (5 mg). In groups BD, BF and BS, 5 μg of dexmedetomidine, 25 μg of fentanyl and 0.5 mL saline were added, respectively. The duration of the motor and sensory blocks in both limbs and the rate of pain during 24 h after surgery were calculated. Hemodynamic changes were also measured during anesthesia for up to 90 min.ResultsThe duration of both of motor and sensory block was significantly longer in dependent limb in the BF (96 and 169 min) and BD (92 and 166 min) groups than the BS (84 and 157 min) group. Visual Analog Scale was significantly lower in the two groups of BF (1.4) and BD (1.3), within 24 h after surgery, than the BS (1.6) group.ConclusionsThe addition of fentanyl and dexmedetomidine to bupivacaine in unilateral spinal anesthesia can increase the duration of the motor and sensory block in dependent limb and prolong the duration of postoperative pain. However, fentanyl is more effective than dexmedetomidine.     

Lidocaine-tramadol versus lidocaine-dexmedetomidine for intravenous regional anesthesia

BackgroundIntravenous regional anesthesia (IVRA) has been used for more than a century. Both tramadol (synthetic opioid) and dexmedetomidine (α₂-agonist) can act locally.Aim of the workTo compare effects of adding tramadol versus dexmedetomidine to lidocaine during IVRA.Patients and methodsSixty patients were randomly assigned into: Group C (n = 20), Group T (n = 20), and Group D (n = 20). All patients received 3 mg/kg 0.5% lidocaine [+100 mg tramadol in Group T, or 1 μg/kg dexmedetomidine in Group D]. Times of onset and offset of sensory and motor blocks, and time to tourniquet pain were recorded. Postoperative VAS score, time to first dose, and total amounts of supplementary analgesia (Paracetamol) were recorded. Sedation was evaluated using Ramsay sedation scale (RSS).ResultsSignificantly shorter onset times and longer recovery times of sensory and motor block were recorded in Groups T and D compared to Group C (P < 0.05); while, with no significant differences between Groups T and D. Delayed onset of tourniquet pain occurred in Groups T and D compared to Group C (P < 0.05) with no significant differences between Groups T and D. Fourteen patients required fentanyl to control tourniquet pain in Group C compared to (5 and 4) in Groups T and D respectively. Significantly lower Postoperative VAS score, longer time to first dose and lower consumption of Paracetamol were recorded in Groups T and D than in Group C; with no significant differences between Groups T and D. Complications were skin rash in 30% of patients in Group T, bradycardia and sedation in 35% and 65% of patients in Group D respectively.ConclusionAddition of either tramadol or dexmedetomidine enhances lidocaine during IVRA with higher incidence of skin rash with tramadol and postoperative bradycardia and sedation with dexmedetomidine.     

Effects of intrathecal bupivacaine–fentanyl versus bupivacaine–dexmedetomidine in diabetic surgical patients

BackgroundDiabetes mellitus is the most common endocrine disorder encountered during anesthesia. Experimental researches showed that the functional μ opioid receptors in the dorsal horn of spinal cord in diabetics are either reduced or impaired in their function. This prospective study was postulated to differentiate between the effects of either opioid like fentanyl versus nonopioid like dexmedetomidine agents added to spinal bupivacaine in diabetic patients.MethodsSixty diabetic patients of either sex were submitted for elective lower limb orthopedic surgery. Patients were randomly allocated into three equal groups (each group 20 patient): bupivacaine group in which patients received 2.5 ml of hyperbaric bupivacaine 0.5% plus 0.5 mL of normal saline, bupivacaine–fentanyl group in which patients received 2.5 ml of hyperbaric bupivacaine 0.5% plus 25 μg fentanyl in 0.5 mL of normal saline and bupivacaine–dexmedetomidine group in which patients received 2.5 ml of hyperbaric bupivacaine 0.5%, plus 10 μg dexmedetomidine in 0.5 mL of normal saline. Duration and quality of sensory and motor block were assessed.ResultsThe duration of sensory and motor block as well as duration of effective analgesia was significantly longer in the bupivacaine–dexmedetomidine group as compared with both bupivacaine–fentanyl and control bupivacaine groups.ConclusionAddition of intrathecal dexmedetomidine to heavy bupivacaine 0.5% was more advantageous than fentanyl with special regard to its analgesic properties in diabetic surgical patients.     

Dexmedetomidine improves intraoperative conditions and quality of postoperative analgesia when added to epidural in elective cesarean section

IntroductionThis study was designed to evaluate the effect of adding dexmedetomidine to regular mixture of epidural drugs for pregnant women undergoing elective caesarian section with special emphasis on their sedative properties, ability to improve quality of intraoperative, postoperative analgesia and neonatal outcome.MethodsFifty women of ASA physical status I or II at term pregnancy were enrolled randomly to receive either plain bupivacaine plus fentanyl (BF group) or plain bupivacaine plus mixture of fentanyl and dexmedetomidine (DBF group). Incidence of hypotension, bradycardia, Apgar scores, intraoperative pain assessment, onset of postoperative pain, sedation scores and side effects were recorded.ResultsNo difference in the times taken for block to reach T4 sensory level, to reach the highest level of sensory block and interval between first neuraxial injection and onset of surgery between the groups. Onset of postoperative pain was significantly delayed in the DBF group (P = 0.001), the need for supplementary fentanyl was significantly less in DBF group (P = 0.03), and no significant difference was obtained between both groups regarding neonatal Apgar scores as well as the incidence of hypotension, bradycardia, nausea, vomiting and duration of motor blockade between the groups. DBF group had significantly less incidence of shivering (P = 0.03).ConclusionAdding dexmedetomidine to regular mixture of epidural anesthetics in women undergoing elective cesarean section improved intraoperative conditions and quality of postoperative analgesia without maternal or neonatal significant side effects.     

The analgesic efficacy of continuous fascia iliaca block vs. continuous psoas compartment block after hip surgery: A comparative study

BackgroundBoth psoas compartment block and fascia iliaca compartment block have been shown to be reliable blocks for postoperative pain relief for procedures involving the hip joint. This study evaluated the efficacy of continuous psoas compartment block with continuous fascia iliaca block for postoperative analgesia after hip surgery.MethodsIn randomized blinded study Forty, ASA I–III patients aged 30–75 years, with BMI less than 40, scheduled for hip surgery, were divided to one of two groups. Group P: continuous psoas compartment block (n = 18) and group F: continuous fascia iliaca block (n = 19). Standard general anesthesia was induced after finishing the block technique. After recovery 30 ml of 0.125% levobupivacaine was injected through the catheter to all patients. Postoperative 24 h meperidine consumption, patient satisfaction, visual analogue scale pain scores at (1, 6, 12, 18, and 24 h) postoperative, postoperative hemodynamics (HR and MAp), evidence of sensory and motor blockades, and incidence of adverse effects were recorded.ResultsThere was no significant difference between the two groups in 24 h postoperative meperidine requirements, postoperative VAS, patient satisfaction, postoperative hemodynamics, and distribution of sensory and motor block of (femoral, lateral femoral cutaneous, and obturator nerves). The epidural anesthesia occurred in two patients in psoas group (11%).ConclusionBoth continuous fascia iliaca block and continuous psoas compartment block were comparable in providing safe and effective analgesia after hip surgery.     

Effects of intravenous ondansetron and granisetron on hemodynamic changes and motor and sensory blockade induced by spinal anesthesia in parturients undergoing cesarean section

BackgroundSpinal anesthesia has many advantages for cesarean section parturients, but hypotension is considered the most frequent complication and can be managed by different interventions. One of these interventions is to give a serotonin receptor antagonist prior to spinal anesthesia.ObjectivesTo compare between two serotonin receptor antagonists on the hemodynamics, sensory, and motor blockade induced by intrathecal bupivacaine in parturients undergoing cesarean section.Patients and methodsSixty patients undergoing elective cesarean section under spinal anesthesia by intrathecal bupivacaine were randomly divided into three groups (20 pregnant females of ASA I–II physical status in each group). Group O received intravenous 4 mg ondansetron diluted in 10 ml normal saline and injected over 1 min, 5 min before spinal anesthesia, group G given intravenous 1 mg granisetron by the same route and group S given 10 ml normal saline. Mean arterial blood pressure, heart rate, vasopressor use, sensory, and motor blockade were assessed.ResultsDecreases in mean arterial pressure were significantly lower in group O than groups G and S with lower vasopressor use (P < 0.05), while there was significant faster sensory recovery in group G than groups O and S (P < 0.05). Actually, there were significant decrease in the incidence of nausea in groups O and G than group S (P = 0.008).ConclusionIn parturient females undergoing elective cesarean section, intravenous 4 mg ondansetron before subarachnoid block significantly decreased both the hypotension and the doses of vasopressor used, while intravenous 1 mg granisetron prior to subarachnoid block induced faster sensory recovery compared to both the ondansetron and the saline groups, with no significant differences between the later two groups.     

The efficacy of preoperative pregabalin on reduction of the incidence and severity of postdural puncture headache after spinal anesthesia

ObjectiveThe aim of this study was to evaluate the efficacy of prophylactic pregabalin on postdural puncture headache incidence and severity after spinal anesthesia.Method86 ASA I-II male and female patients age 20–50 years old, undergoing elective general surgeries below the umbilicus under spinal anesthesia with 3 ml heavy bupivacaine 0.5% (15 mg), patients were randomly allocated into one of two groups (Group C, n = 43) (control group) received a placebo capsule 2 h preoperatively (Group P, n = 43) received 150 mg pregabalin capsule 2 h preoperatively, number of attempts for spinal block, sensory level, motor block grade, postoperative time to first analgesic requirement, the incidence, onset and intensity of PDPH and adverse events were recorded for 72 h.ResultsThe peak sensory level in C group and P group showed no statistical significant difference, the time to peak sensory block was significantly earlier in P group than group C, the time to reach the modified Bromage motor block grade 3 was significantly earlier in P group than C group, time to two segment regression of sensory level to S1 and motor block regression to modified Bromage grade 0 were statistically insignificant between the studied groups. Group P had a significantly longer time to first analgesic requirements than group C, and there was no significant difference in VAS (visual analogue scale) of pain between the studied groups. There was significant increase in sedation score in P group compared to C group at 2 h and 6 h postoperatively, and there was statistically significant reduction in the incidence rate and severity of PDPH in P group compared to group C. There were no recorded cases of dizziness, visual disturbances, or PONV.Conclusionspreoperative oral pregabalin 150 mg reduced the incidence and severity of PDPH, beside the earlier onset of peak sensory and motor block with increase duration of analgesia in patients undergoing elective surgeries under spinal anesthesia.     

Postural change from lateral to supine is an important mechanism enhancing cephalic spread after injection of intrathecal 0.5% plain bupivacaine for cesarean section

BackgroundSpinal anesthesia is widely used for cesarean section, but the factors that affect the spread of the block in pregnant patients are still not fully explained. This study was designed to investigate the effect of postural changes on sensory block level.MethodsThirty patients scheduled for elective cesarean section under combined spinal–epidural anesthesia were randomly allocated into three groups. After intrathecal injection of 0.5% plain bupivacaine 7.5 mg, patients in group S were immediately placed in the supine position with left tilt, patients in group L5 were kept lateral for 5 min and then turned to the supine position with left tilt, and patients in group L10 were kept lateral for 10 min and then turned to the supine position with left tilt.ResultsAt 5 min, median cephalad level of sensory block was lower in groups L5 and L10 compared with group S (corrected P<0.001); at 10 min, median cephalad sensory block level was lower in group L10 compared with group S (corrected P<0.001) and group L5 (corrected P<0.001), and lower in group L5 compared with group S (corrected P=0.033); at 15 min, median cephalad level of sensory block was lower in group L10 compared with group S (corrected P=0.003) and group L5 (corrected P=0.015).ConclusionsIn our population, using 0.5% plain bupivacaine 7.5 mg, postural change from the lateral position to the supine position is an important mechanism enhancing cephalic spread of spinal anesthesia during late pregnancy.     

The effect of gabapentin premedication on pain and anxiety during cataract surgery under peribulbar block

BackgroundThe principal goal of sedation during eye surgery is to keep the patient calm and comfortable without depression of the protective airway reflexes or affecting the hemodynamics. The aim of the present study was to evaluate the effect of oral gabapentin premedication on anxiety and pain during cataract surgery done under peribulbar block.Material and methodsIn this double blinded placebo controlled study, 60 patients scheduled for cataract surgery under peribulbar block were randomly allocated into two groups. In the gabapentin group (n = 30), patients were premedicated 2 h before peribulbar block by 1200 mg oral gabapentin capsules. In the placebo group (n = 30), patients were premedicated 2 h before peribulbar block by oral placebo capsules. Verbal pain score (VPS), sedation score, verbal anxiety score (VAS), respiratory rate, oxygen saturation, heart rate, blood pressure and side effects were recorded.ResultsVPS was low in the gabapentin group versus the placebo group after the block till discharge (P < 0.01). VAS for anxiety was low in the gabapentin group versus the placebo group 1 h after premedication till discharge (P < 0.01). The heart rate and blood pressure were high in the placebo group versus the gabapentin group from arrival to the operating room till discharge. No side effects were recorded.ConclusionPremedication with 1200 mg oral gabapentin reduces anxiety and pain during cataract surgery done under peribulbar block without producing side effects.     

Dexmedetomidine decreases the required amount of bupivacaine for ultrasound-guided transversus abdominis plane block in pediatrics patients: a randomized study

BackgroundThe effect of dexmedetomidine on the potency of bupivacaine for transversus abdominis plane (TAP) block in pediatric patients has not been investigated.Study objectiveThe primary objective of this study was to assess the effectiveness of dexmedetomidine to decrease the concentration of bupivacaine needed for analgesia for ultrasound-guided TAP block in a pediatric patient undergoing hernia repair or hydrocelectomy.DesignThis is a randomized, double-blind, up-down, dose-finding study.SettingOperating room.PatientsSixty American Society of Anesthesiologists I and II patients aged 1-4 years scheduled for elective unilateral herniorrhaphy or hydrocelectomy.InterventionsPatients were randomly assigned to 1 of the 2 groups: group B (0.125% bupivacaine, 1 mL/kg) TAP block or group BD (0.125% bupivacaine plus 2 μg/kg dexmedetomidine, 1 mL/kg) TAP block.MeasurementsThe response of each child was observed for 60 seconds after skin incision and evaluated as ‘unsuccessful’ when skin incision caused a change in hemodynamic parameters (heart rate and mean blood pressure) 20% more than the preincision values. If the response was determined to be unsuccessful, the concentration of bupivacaine administrated to the next patient was increased by 0.02%. If it was successful, the concentration of bupivacaine administrated to the next patient was decreased by 0.02%.ResultsThe minimum local anesthetic concentration of bupivacaine was 0.0839% (0.0137) in the B group and 0.0550% (0.0169) in the BD group. The difference was statistically significant (t = 7.165, P = .0001). The total postoperative analgesic dosage of morphine was significantly higher in the B group (0.17 ± 0.04 mg/kg) than the BD group (0.11 ± 0.02 mg/kg, P = .001).ConclusionsThe addition of 2 μg/kg of dexmedetomidine reduced the minimum local anesthetic concentration of bupivacaine used for a TAP block and improved postoperative analgesia in children undergoing surgery for inguinal hernia repair or hydrocelectomy.     

Single shot spinal anesthesia with very low hyperbaric bupivacaine dose (3.75 mg) for hip fracture repair surgery in the elderly. A randomized,double blinded study

PurposeSingle shot spinal anesthesia is used worldwide for hip fracture repair surgery in the elderly. Arterial hypotension is a frequent adverse effect. We hypothesized that lowering local anesthetics dose could decrease the incidence of arterial hypotension, while maintaining quality of surgical anesthesia.MethodsIn a randomized double blinded study, 66 patients over the age of 65 years, with hip fracture needing surgical repair, were assigned to B0.5 group 7.5 mg hyperbaric bupivacaine 5 mg/ml (control group), and B0.25 group 3.75 mg hyperbaric bupivacaine 2.5 mg/ml (study group). Sensory and motor block level, and hemodynamic parameters including blood presure, heart rate and vasopressor dose administration were registered, along with rescue anesthesia needs, the feasibility of surgery, its duration, and regression time of sensory anesthesia to T12.ResultsAfter exclusions, 61 patients were included in the final analysis. Arterial hypotension incidence was lower in the B0.25 group (at the 5, 10, and 15 min determinations), and a lower amount of vasopressor drugs was needed (mean accumulated ephedrine dose 1.6 mg vs. 8.7 mg in the B0.5 group, p < 0.002). Sensory block regression time to T12 was shorter in the B0.25 group, mean 78.6 ± 23.6 (95% CI 51.7–110.2) min vs. 125.5 ± 37.9 (95% CI 101.7–169.4) min in the B0.5 group, p = 0.033. All but one patient in the B0.25 group were operated on under the anesthetic procedure first intended. No rescue anesthesia was needed.ConclusionLowering bupivacaine dose for single shot spinal anesthesia for hip fracture repair surgery in elderly patients was effective in decreasing the occurrence of arterial hypotension and vasopressor use, while intraoperative quality remained.     

Ultrasound-guided supraclavicular versus infraclavicular brachial plexus nerve block in chronic renal failure patients undergoing arteriovenous fistula creation

BackgroundMost patients with chronic renal failure suffer from complications that make brachial plexus block a good choice for providing anesthesia. The use of ultrasonography increases the success rate and decreases complications. We compared the efficacy of ultrasound-guided supraclavicular and infraclavicular brachial plexus block in providing anesthesia for creation of arteriovenous fistula.Patients and methodsSixty adult patients with chronic renal failure, scheduled for creation of arteriovenous fistula of the distal upper extremity were randomly divided into two equal groups: Supra G (n = 30): ultrasonic guided supraclavicular brachial plexus block was given and Infra G (n = 30): ultrasonic guided infraclavicular brachial plexus block was given. For both groups we used 20–25 cm 1:1 volumes of 0.5% bupivacaine and 2% lidocaine. The measured parameters were block performance time and related pain, the degree and duration of sensory and motor block, patient discomfort, first call for analgesics, complications and the patient’s satisfaction.ResultsThere was no statistically significant difference between both groups as regard the block performance time, the block related pain, the degree of sensory and motor block in the areas supplied by the median, radial and musculocutaneous nerves at 10, 20 and 30 min. There was no statistically significant difference as regard the sensory block grade in the area supplied by the ulnar nerve at 10 min, but it was significantly higher in the Supra G than Infra G at 20 and 30 min. No statistically significant difference as regard the motor block grade in the area supplied by the ulnar nerve, the block duration, first call for analgesia, complications and patients’ satisfaction.ConclusionBoth approaches can provide satisfactory sensory and motor block, very good analgesia that extends for a long time postoperatively in patients with chronic renal failure undergoing creation of arteriovenous fistula.     

Sciatic nerve block made easy for resident trainers

BackgroundThe infragluteal parabiceps approach to sciatic nerve might be easier to be learnt by trainees with reasonable success rate and performance time and less incidence of complications.MethodsAfter ethical approval, infragluteal and Labat approaches for sciatic nerve block (n = 50 for each) were performed by five trainees at 3rd grade of anesthesia training program. We recorded the changes in the times to performance of the block, and onset of sensory block, the patients' satisfaction and difficulty of the technique for the trainees.ResultsPerformance time was 3–3.5 min with Labat approach and 2–2.75 min with infra-gluteal approach (P < 0.001). Sciatic nerve stimulation was observed at a depth of 70 ± 8 mm after (2–10) needle redirection in group Labat, and at a depth of 58 ± 13 mm after (2–7) needle redirection in infragluteal group (P < 0.001). Failed nerve block was reported in 5 cases in group Labat and 2 cases in infra-gluteal group (P = 0.13). Thirty cases in Labat group would refuse the same anesthetic if required in the future for another surgery, while only twenty five cases in infragluteal group would refuse the same technique in the future (P = 0.13). Three resident trainer described the infragluteal approach as a simple approach and easy to perform by a beginner, whereas only two trainers accepted the Labat approach (P = 0.52).ConclusionInfragluteal approach for the sciatic nerve block was considered rapidly and easy to use and the preferred approach regardless of previous experience compared with Labat approach.     

Dexmedetomidine acts as an oxidative damage prophylactic in rats exposed to ionizing radiation

Study objectiveTo investigate the effects of dexmedetomidine on oxidative injury caused by ionizing radiation.DesignRandomized controlled experimental study.SettingDepartment of radiation oncology and research laboratory of an academic hospital.InterventionsTwenty-eight rats were randomized to 4 groups (n = 7 per group). Group S rats were administered physiologic serum; group SR rats were administered physiologic serum and 10 Gy external ionizing radiation. Groups D100 and D200 were administered 100 and 200 μg/kg dexmedetomidine intraperitoneally, respectively, 45 minutes before ionizing radiation.MeasurementsLiver, kidney, lung, and thyroid tissue and serum levels of antioxidant enzymes (glutathione peroxidase [GPX], superoxide dismutase, and catalase) and oxidative metabolites (advanced oxidation protein products, malondialdehyde, and nitrate/nitrite, and serum ischemia-modified albumin) were measured 6 hours postprocedure.Main resultsIn group SR, IR decreased antioxidant enzyme levels and increased oxidative metabolite levels (P < .05). In plasma, antioxidant enzyme levels were higher and oxidative metabolite levels were lower in groups D100 and D200 than in group SR (P < .01). In tissues, hepatic and lung GPX levels were higher in groups D100 and D200 than in group SR (P < .001). Renal and thyroid GPX levels were higher in D200 than in group SR (P < .01). Thyroid superoxide dismutase levels were higher in groups D100 and D200 than in group SR (P < .01). Renal, lung, and thyroid catalase levels were higher in group D200 than in group SR (P < .01). Hepatic, renal, and lung advanced oxidation protein products and malondialdehyde levels were lower in groups D100 and D200 than in group SR (P < .01). Hepatic, renal, and lung nitrate/nitrite levels were lower in group D200 than in group SR (P < .05).ConclusionsDexmedetomidine preserves the antioxidant enzyme levels and reduces toxic oxidant metabolites. Therefore, it can provide protection from oxidative injury caused by ionizing radiation.     

Intrathecal vs intravenous magnesium as an adjuvant to bupivacaine spinal anesthesia for total hip arthroplasty

BackgroundThe aim of this study was to investigate the effect of intravenous infusion vs intrathecal magnesium sulfate during spinal anesthesia on postoperative pain, analgesic consumption, and intraoperative blood loss on patients undergoing total hip arthroplasty surgery.MethodsIn this prospective randomized controlled study, 75 adult patients, ASA physical status I and II scheduled for total hip arthroplasty, were included and randomized into three groups. Patients in Group I (control) received spinal anesthesia with hyperbaric bupivacaine and fentanyl. In Group II (IT Mg), 50 mg of magnesium sulfate was added to bupivacaine and fentanyl. In Group III (IV Mg), after induction of spinal anesthesia as in group I, a bolus dose of i.v. magnesium sulfate 40 mg kg^?1 was injected over 10 min, followed by continuous infusion of 15 mg kg^?1 h^?1 till the end of surgery. Arterial blood pressure, heart rate, electrocardiography, and O₂ saturation were continuously monitored. Onset, duration of sensory and motor block, and postoperative pain scores were assessed. Serum magnesium concentrations were checked before induction of anesthesia, immediately after surgery, at 6 h and 24 h after surgery. Total analgesic consumption and intraoperative blood loss were calculated.ResultsThere were no significant differences between the study groups in terms of onset time and maximum sensory level achieved, as well as onset and duration of motor block. Postoperative pain scores and 24 h analgesic consumption were lower in group II and III with insignificant differences between them. Intraoperative blood loss was significantly lower in group III. Postoperative Mg levels were higher in group III, without significant side effects.ConclusionsBoth i.v. infusion and intrathecal injection of Mg sulfate improved postoperative analgesia after total hip replacement. In addition, i.v. infusion of Mg sulfate reduced intraoperative blood loss.     

Comparison of caudal epidural block and ultrasonography-guided transversus abdominis plane block for pain relief in children undergoing lower abdominal surgery

Study objectiveWe conducted this study to compare the efficacy of caudal epidural block (CEB) vs ultrasonography-guided transversus abdominis plane (TAP) block for providing postoperative pain relief in children scheduled for lower abdominal surgery. Whereas the primary objective was to compare the duration of postoperative analgesia, the secondary objectives included comparative assessment (TAP vs CEB) of quality of pain relief in the first 24 hours postoperatively and rescue analgesia requirements.DesignRandomized-control, prospective, observer-blinded, 2-arm, single-center comparison.SettingOperating room, postoperative recovery area.PatientsEighty-children, aged 2-6 years, of American Society of Anesthesiologists physical status I/II scheduled to undergo unilateral lower abdominal surgery under general anesthesia.InterventionsThe recruited children were randomly allocated to receive under general anesthesia either CEB (group C, 0.75 mL/kg of 0.25% bupivacaine) or ultrasonography-guided administration of TAP block (group T, 0.5 mL/kg of 0.25% bupivacaine).MeasurementsIntraoperative: heart rate and noninvasive blood pressure; postoperative: pain profile, including duration of postoperative analgesia, quality of pain relief, and rescue analgesia requirements.Main resultsThe median duration of postoperative analgesia was significantly greater in children who received CEB than those who were administered TAP block (group C: 362.5 minutes [172.5-693.75] vs group T: 210 minutes [108.75-362.5]; P < .05). No difference was found in the incidence of postoperative pain up to 6 hours from the point of initiation of assessment (group C: 47.2% vs group T: 55.9%; P > .05). The children who received CEB experienced greater incidence of pain in the 6- to 24-hour postoperative interval than those administered TAP block (group C: 75% vs group T: 44.1%; P < .05). Although there was no difference in the rescue analgesia requirements, the number of children not requiring any rescue analgesia in the first 24 hours postoperatively was significantly higher in the TAP group (group C: n = 2 vs group T: n = 8; P < .05).ConclusionsIn children undergoing lower abdominal surgery, CEB provides a significantly prolonged duration of postoperative analgesia when compared with ultrasonography-guided TAP block.     

Dexmedetomidine as a hypotensive agent: Efficacy and hemodynamic response during spinal surgery for idiopathic scoliosis in adolescents

BackgroundThis study was designed to evaluate the efficacy of dexmedetomidine as a hypotensive agent in comparison to sodium nitroprusside in scoliosis surgery.MethodForty patients ASA I or II aged (12–16) year scheduled for scoliosis surgery were randomly assigned to receive either dexmedetomidine 1 μg/kg over 10 min before induction of anesthesia followed by 0.2–0.5 μg/kg/h infusion during maintenance (DEX group) or sodium nitroprusside 1–10 μg/kg/min infusion after induction of anesthesia (SNP group) to maintain mean arterial blood pressure between (60–65 mmHg). Mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), systemic vascular resistance index (SVRI) and stroke index (SI) were recorded. The two groups were compared with reference to reversibility of hypotensive state, intraoperative blood loss and transfusion requirement.ResultsDexmedetomidine administration resulted in significant reduction in MAP, HR and CI. During the steady state hypotension SNP group showed significant increase in HR and CI compared to baseline and to DEX group (P < 0.05). SVRI was significantly lower during controlled hypotension in SNP group compared to DEX group (P < 0.001). Time to restoration of baseline MAP was longer with DEX group (10.21 ± 1.52 min) than SNP group (4.87 ± 0.86 min) (P < 0.001). Blood loss and transfusion requirement were significantly lower in DEX group than SNP group [1095.62 ± 128.9 6 ml versus 1287.50 ± 182.54 ml, P = 0.0013] and [855.42 ± 140.23 versus 1006.00 ± 154.66 ml, P = 0.0026], respectively.ConclusionDexmedetomidine is a safe and effective drug for controlled hypotension in scoliosis surgery. It may offer the significant advantage of reducing blood loss and transfusion requirement.     

Efeitos de dexmedetomidina em conjunto com o pré‐condicionamento isquêmico remoto em lesão de isquemia‐reperfusão renal em ratos

Background and objectivesThe aim of this study was to evaluate the effects of remote ischemic preconditioning by brief ischemia of unilateral hind limb when combined with dexmedetomidine on renal ischemia–reperfusion injury by histopathology and active caspase‐3 immunoreactivity in rats.Methods28 Wistar albino male rats were divided into 4 groups. Group I (Sham, n = 7): Laparotomy and renal pedicle dissection were performed at 65th minute of anesthesia and the rats were observed under anesthesia for 130 min. Group II (ischemia–reperfusion, n = 7): At 65th minute of anesthesia bilateral renal pedicles were clamped. After 60 min ischemia 24 h of reperfusion was performed. Group III (ischemia–reperfusion + dexmedetomidine, n = 7): At the fifth minute of reperfusion (100 μg/kg intra‐peritoneal) dexmedetomidine was administered with ischemia–reperfusion group. Reperfusion lasted 24 h. Group IV (ischemia–reperfusion + remote ischemic preconditioning + dexmedetomidine, n = 7): After laparotomy, three cycles of ischemic preconditioning (10 min ischemia and 10 min reperfusion) were applied to the left hind limb and after 5 min with group III.ResultsHistopathological injury scores and active caspase‐3 immunoreactivity were significantly lower in the Sham group compared to the other groups. Histopathological injury scores in groups III and IV were significantly lower than group II (p = 0.03 and p = 0.05). Active caspase‐3 immunoreactivity was significantly lower in the group IV than group II (p = 0.01) and there was no significant difference between group II and group III (p = 0.06).ConclusionsPharmacologic conditioning with dexmedetomidine and remote ischemic preconditioning when combined with dexmedetomidine significantly decreases renal ischemia–reperfusion injury histomorphologically. Combined use of two methods prevents apoptosis via active caspase‐3.