Thoracic paravertebral nerve block(TPVB)is a regional anesthesia technique that pro-vides ipsilateral somatosensory,motor and sympathetic nerves block segmentally by injecting local anesthetics in the paravertebral space.In recent years,there has been an increasing number of studies on the use of TPVB technique for anesthesia and analgesia in pediatric thoracic and upper abdominal surgery,showing good perioperative analgesic efficacy.This article intends to provide a review of the current applica-tion and progress of TPVB technique for pediatric perioperative analgesia in terms of medication regimens,drug diffusion routes,block methods,clinical application,and complications.

Ischemia-reperfusion (I / R) is a complex hemodynamic process that can cause tissue damage through oxidative stress, mitochondrial dysfunction, and inflammatory reactions. It is an important factor leading to poor prognosis in patients, and the exploration of effective prevention and treatment measures is of significant clinical significance. As an endogenous hormone with strong antioxidant and anti-inflammatory properties, Melatonin plays an important role in reducing cell death and improving tissue I / R injury. Therefore, this article reviews the relationship between Melatonin and organ I/R injury in order to provide a theoretical basis for the clinical application of melatonin to alleviate organ I/R injury.

Objective To compare two different regimens of ultrasound-guided Continuous ad-ductor canal block (CACB)for postoperative analgesia and early ambulation after total knee arthro-plasty (TKA).Methods Sixty-seven patients scheduled for unilateral TKA undergoing spinal anes-thesia,13 males and 54 females,aged 18-85 years,BMI 18-30 kg/m2,ASA physical status Ⅰ-Ⅲ, were randomly divided into the continuous infusion group A (n=34)and the intermittent boluses group B (n=33).After the operations,ultrasound-guided CACB were administered and 20 ml of 0.2% ropivacaine was given as the loading dose.From then on,patients in both groups used electronic analgesic pumps containing 240 ml of 0.2% ropivacaine for postoperative analgesia.5 ml/h of 0.2% ropivacaine was continuously infused for 48 hours in the group A.5 ml of 0.2% ropivacaine was automated injected every 60 minutes in the group B.All infusion pumps were setted at a bolus dose of 5 ml,with a lock time of 30 minutes.The total consumptions of analgestic pum solution and dezoine, quadriceps muscle strength, active range of knee flexion, ambulation distance and occurrences of adverse reactions such as nausea and vomiting,dizziness,drowsiness,extravasating and errhysis were recorded at different time points postoperatively.Results The total consumptions of analgestic pum solution at 12,24 h postoperatively of group B were significantly reduced than that of group A (P<0.05).The 48 h total dezoine consumption of group B was significantly reduced than group A (P<0.05).Active range of knee flexion at 24,48 h and ambulation distance at 48,72 h of group B were significantly higher than group A (P<0.05).There was no statistical difference in quadriceps muscle strength between group A and group B.The incidence of nausea and vomiting in group A was significantly higher than that in group B,and there were no statistical difference in other adverse reactions between group A and group B.Conclusion Compared with the continuous infusion group,the intermittent bolus group for CACB after TKA can provide better analgesic effect and de-crease opioid use postoperatively,with little effect on motor nerve,promoting early ambulation.

Objective To evaluate the efficacy of hydromorphone for postoperative parent-controlled intravenous analgesia in pediatric patients.Methods Seventy-five pediatric patients of both sexes,aged 2-5 yr,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,scheduled for elective surgery for treatment of developmental displasia of the hip,were divided into 2 groups using a random number table:sufentanil group (group S,n =38) and hydromorphone group (group H,n =37).Parent-controlled intravenous analgesia was carried out within 48 h after operation.Parent-controlled intravenous analgesia solution contained sufentanil 2 μg/kg (group S) or hydromorphone 200 μg/kg (group H) in 100 ml of normal saline.The analgesia pump was set up with a 0.5 ml bolus dose,a 15-min lockout interval and infusion at a rate of 0.5 ml/h.Ramsay sedation scores were recorded at 0.5,1,4,8,12,24 and 48 h after extubation (T1-7).At 1 h before operation (To),T3 and T6,blood samples were collected from the ulnar vein for determination of the concentration of substance P in serum.The total consumption of analgesics,the number of successfully delivered doses,the number of attempts and drug-related adverse reactions were recorded,and parents' satisfaction was scored.Results Compared with group S,Ramsay sedation scores were significantly decreased at T1-3,the number of attempts was increased (P＜0.05),and no significant change was found in the total consumption of analgesics,the number of successfully delivered doses,degree of parents' satisfaction,serum concentration of substance P or incidence of drug-related adverse reactions in group H (P＞0.05).Conclusion Hydromorphone can be safely and effectively used for postoperative parent-controlled intravenous analgesia in pediatric patients.

Objective To compare the impact of propofol and sevoflurane on thermoregulation in children undergoing orheopaedic surgery.Methods Sixty-eight children scheduled to undergo ortho-paedic surgery were randomly allocated to receive propofol (group P)and sevoflurane(group S)anes-thesia,34 cases in each group.Tympanic temperature was recorded 5 minutes before (T0 )and 5 min (T1 ),1 5 min (T2 ),30 min (T3 ),45 min (T4 ),60 min (T5 ),75 min (T6 ),90 min (T7 ),105 min (T8 )and 120 min (T9 )after anesthesia.Total fluid intake,duration of surgery,duration of anesthe-sia,the incidence of hypothermia,and the incidence of shivering were also recorded.Results Com-pared with T0 ,in both groups body temperature declined at T1-T8 .There was no difference between the two groups in total fluid intake,duration of surgery,duration of anesthesia and the incidence of shivering.Compared with group P,children in group S had a higher incidence of hypothermia(8 vs 1). Children in group S had lower temperature,which had statistical significance at T7 and T8 (P <0.05). Conclusion The core temperature of children undergoing orthopaedic surgery showed a trend of in-crease after the first fall in the surgery.Compared with propofol,sevoflurane anesthesia is more likely to lead to the incidence of hypothermia in children undergoing orthopaedic surgery in 90 min after in-duction of anesthesia.

Objective To evaluate the role of spinal c?Jun N?terminal kinase ( JNK ) signaling pathway in incisional pain in rats. Methods Sixty?three adult male Sprague?Dawley rats, weighing 200-250 g, were randomly divided into 3 groups ( n=21 each) using a random number table: incisional pain group ( IP group) , dimethyl sulfoxide ( DMSO) group, and JNK inhibitor SP600125 group ( SP group) . A 1?cm longitudinal incision was made through skin, fascia and muscle of the plantar aspect of the hindpaw in anesthetized rats. In group DMSO, 10% DMSO 10 μl was injected intrathecally at 30 min before surgery. In group SP, SP600125 25 μg (in 10 μl of 10% DMSO) was injected intrathecally at 30 min before sur?gery. Six rats in each group were sacrificed, and the mechanical paw withdrawal threshold ( MWT) and thermal paw withdrawal latency ( TWL) were measured at 24 h before establishment of the model and 2, 6, 24, 48 and 72 h after establishment of the model. After measurement of the pain threshold at 24 h before establishment of the model and 6, 24, 48 and 72 h after establishment of the model, the lumbar segment of the spinal cord was removed for determination of the expression of phosphorylated JNK ( p?JNK) by im?munofluorescence. Results The MWT was significantly lower, the TWL was shorter, and the expression of p?JNK was lower at each time point after establishment of the model than at 24 h before establishment of the model in group IP (P<0?05). Compared with group IP, the MWT was significantly increased, the TWL was prolonged, and the expression of p?JNK was down?regulated at each time point after establishment of the model in group SP ( P<0?05) , and no significant change was found in the parameters mentioned a?bove in group DMSO ( P>0?05) . Conclusion Spinal JNK signaling pathway is involved in the develop?ment and maintenance of incisional pain in rats.

Objective To investigate the effects of different doses of dexmedetomidine on perioperative inflammatory responses in patients undergoing one-lung ventilation (OLV).Methods Thirty-six ASA T or Ⅱ patients (aged 43-72 years and weighing 50-78 kg) scheduled for esophagectomy were randomly divided into three groups (n =12 each):control group (group C),low dose dexmedetomidine group (group D1) and high dose dexmedetomidine group (group D2).Dexmedetomidine 1 μg/kg was infused intravenously 10 minutes before anesthesia induction,then infused at a rate of 0.2 μg· kg-1 · h-1 (group D1) or 0.5 μg· kg-1· h-1 (group D2) until 30 minutes before the end of operation.Group C received the equal volume of normal saline.Blood samples were collected before anesthesia induction (T0),immediately before OLV (T1),30 minutes after OLV (T2),90 minutes after OLV (T3),30 minutes after lung inflation (T4) and 2 hours after operation (T5) for monitoring serumlevels of tumor necrosis factor-alpha (TNF-α) and interleukin-8 (IL-8).Results Compared with T0,serum levels of TNF-α and IL-8 significantly increased at T3 and T5 in all the three groups (P ＜ 0.05).Compared with group C,serum levels of TNF-α and IL-8 significantly decreased at T3 and T5 in group D2 (P ＜ 0.05).There was no significant difference in the indexes mentioned above between group C and group D1 (P ＞ 0.05).Conclusion Dexmedetomidine 1 μg/kg given before anesthesia induction and then infused at the rate of 0.5 μg· kg-1 ·h-1 during operation can reduce inflammatory responses in patients undergoing OLV.

Objective To evaluate the role of mitochondrial ATP-sensitive potassium (mito-KATP) channels in attenuation of renal ischemia-reperfusion (I/R) injury by lidocaine pretreatment in rats.Methods Sixty healthy male Wistar rats,weighing 300-350 g,were randomly assigned into 5 groups (n =12 each) using a random number table:sham operation group (group S); renal I/R group (group I/R); lidocaine pretreatment group (group L) ; 5-HD (a specific blocker of the mito-KATP channel) group and 5-HD + lidocaine pretreatment group (group 5-HD + L).Renal ischemia was induced by occlusion of bilateral renal arteries for 60 min with atraumatic microclips followed by 4 h reperfusion.At 60 min before renal ischemia,lidocaine 5 mg/kg was intravenously injected followed by continuous infusion at 2 mg· kg-1 · h-1 in group L.5-HD 10 mg/kg was injected intraperitoneally at 65 min before ischemia in group 5-HD.In 5-HD + L groups,5-HD 10 mg/kg was injected intraperitoneally at 65 min before ischemia and the other procedures were similar to those previously described in group L.In S and I/R groups,the animals received equal volumes of normal saline instead of lidocaine.Blood samples were obtained at 6 h of reperfusion for determination of serum creatinine (Cr) and urea mitrogen (BUN) concentrations.Bilateral kidneys were removed for determination of mitochondrial membrane potential in the renal tubular epidural cells,malondialdehyde (MDA) content,and superoxide dismutase (SOD) activity and for microscopic examination.Results Compared with group S,the serum Cr and BUN concentrations and MDA content were significantly increased,and SOD activity and mitochondrial membrane potential were decreased in I/R,L,5-HD and 5-HD + L groups (P ＜ 0.05).Compared with group I/R,the serum Cr and BUN concentrations and MDA content were significantly decreased,and SOD activity and mitochondrial membrane potential were increased in L and 5-HD + L groups (P ＜ 0.05),and no significant changes were found in the serum Cr and BUN concentrations,MDA content,SOD activity and mitochondrial membrane potential in group 5-HD (P ＞ 0.05).Compared with group L,the serum Cr and BUN concentrations and MDA content were significantly increased,and SOD activity and mitochondrial membrane potential were decreased in 5-HD + L group (P ＜ 0.05).The pathological changes were significantly reduced in group L as compared with I/R and 5-HD + L groups.Conclusion Mito-KATp channels are involved in reduction of I/R-induced renal injury by lidocaine pretreatment in rats.

ObjectiveTo investigate the effect of infusion of esmolol on expression of hypoxia inducible factor-1α following spinal ischemia-reperfusion (I/R) in rats.MethodsThirty-six healthy male Wistar rats weighing 300-350 g were randomly assigned into 3 groups (n =12 each):group Ⅰ sham operation (group S); group Ⅱ spinal I/R and group Ⅲ esmolol pretreatment (group E).Spinal ischemia was produced by cross-clamping of abdominal aorta distal to renal artery for 20 min in I/R and E groups,Infusion of esmolol 200 g· kg- 1 ·min- 1 was initated 30 min before spinal ischemia and continued for the subsequent 1 h reperfusion in group Ⅲ (E).In groups S and I/R the animals received equal volumes of NS instead of lidocaine.Neurological behavior was assessed according to Tarlov scoring system at 24 and 48 h of reperfusion.The lumbar segment ( L4、5 ) spinal cord was resected at 24 and 48 h ofreperfusion for microscopic examination.The expression of HIF-Ia in spinal cord was detected by immunohistochemistry analysis.ResultsCompared with group S,the expression of HIF-Iα in spinal cord was down-regulated,and Tarlov score was significantly decreased in groups S and l/R.The spinal cord injury was attenuated in group E compared with group I/R.CondusionEsmolol infusion can protect the spinal cord against I/R injury,and inhibition of the expression of HIF-1α is involved in the mechanism.

Objective To investigate the effect of lidocaine pretreatment on renal HMGB1 expression during renal ischemia-reperfusion (I/R) in rats.Methods Thirty-six male Wistar rats weighing 300-350 g were randomly divided into 3 groups ( n=12 each):sham operation group (group S),I/R group and lidocaine pretreatment group (group L).Renal I/R was induced by occlusion of bilateral renal arteries for 60 min followed by 4 or 24 h reperfusion.Lidocaine 5 mg/kg was injected iv at 60 min prior to ischemia followed by 2 mg· kg- 1· h- 1 infusion iv for 60 min in group L.Equal volume of normal saline was given in group I/R.Six rats in each group were sacrificed at 4 or 24 h of reperfusionand their kidneys were removed for microscopic examination and for determination of SOD activity,MDA content and the expression of HMGB1 mRNA and protein.Results Compared with group S,renal HMGB1 mRNA and protein expression,MDA content were significantly increased,while SOD activity were significantly decreased in groups I/R and L( P ＜ 0.05).Compared with group I/R,renal HMGB1 mRNA and protein expression,and MDA content were significantly decreased,while SOD activity were significantly increased in group L ( P ＜ 0.05 ).Conclusion Lidocaine pretreatment can attenuate renal I/R injury in rats by down-regulating HMGB1 expression