The Relevant Clinical Research For Transversus Abdominis Plane Block In Infants And Young Children

Transversus abdominis plane block?TAPB?is a kind of regional block analgesia for abdomen,which block the nerve that pass through the abdominal wall of transversus abdominis fascial plane providing effective analgesia for anterior abdominal wall skin,muscles and the parietal peritoneum.At present,with the application of ultrasound imaging in clinical anesthesia,ultrasound-guided TAPB in children has gradually increased,becoming one of the important components of multimodal analgesia in children.The ultrasonographic changes,effective dosages of drug and different puncture approach in infants and young children with TAPB were researched in this study.Part 1: The effects of analgesia and the changes of ultrasound imaging during operation for different volumes of 1%lidocaine in infants and young children with TAP blockObjective: To compare the effects of analgesia and the changes of ultrasound imaging during operation with different volumes of 1% lidocaine in infants and young children with TAP block.Methods: 60 infants and young children undergoing elective unilateral inguinal hernia or hydrocele were enrolled according to inclusive criteria,40 males,20 females.Children were randomly divided into three groups: L_0.3,L_0.5 and C,20 patients were included in each group.After sevoflurane inhalating induction in all children,ultrasound-guided TAPB were successfully performed by a lateral mid-axillary approach.The children in group L_0.3 were injected 1% lidocaine0.3ml/kg,group L_0.5 were injected 1% lidocaine 0.5ml/kg and group C were injected normal saline 0.3ml/kg or 0.5ml/kg.Under midazolam sedation,onset time and the blocked dermatomal level of lidocaine were tested by pinprick.After tests were completed,the anesthesia were inducted with sevoflurane inhalation and followed by laryngeal mask insertion.Then anesthesia was maintained with 3%sevoflurane.According to changes in heart rate and blood pressure,adjust the amount of continuous or interrupt infusion of remifentanil.The offset time of TAP block was tested postoperatively.The distances of cephalad-caudad expansion,anterior-posterior expansion of local anesthetic solution,the biggest distance between abdominal internal oblique muscle and transverse abdominal muscle?I-T?in TAP,the distance between the lower costal margin or iliac crest and the injectate were measured by ultrasonography in the midaxillary line after the injection of lidocaine,onset time of the blocking and postoperation.The onset time,extent and duration of TAP blockage and ultrasonic image changes at different points of time were recordedResults: 1.There were no difference from onset time and the duration of TAPB between group L_0.3 and group L_0.5?P>0.05?;Dermatomal level of TAPB reached up to T10 level in group L_0.5,and was higher than which in group L_0.3?P<0.01?.The dosage of remifentanil were consumed lesser in group L_0.3 and group L_0.5 compared with group C?P<0.01?,but there was no difference between group L_0.3 and group L_0.5?P>0.05?.2.Ultrasonographic changes followed by spread of injectate after TAP block with different volume of 1% lidocaine in infants and young children: The ultrasonic image displayed spindle-shaped or spoon-shaped liquid cavity after the injection in TAP.After injection and onset time of TAPB,the distances of cephalad-caudad expansion,anterior-posterior expansion of local anesthetic solution were increased,and the distance from injectate to rib edge was reduced;however there were no changes for those distance compared postoperation to onset time of TAPB.At different observational time points,the distance from injectate to rib edge was closer,expansive distance in the other direction was greater in group L_0.5 than group L_0.3.The posterior expansion for injectate was more than anterior,but there was no obvious difference from expansive distance for anterior or posterior unilate between the two groups.The distance of I-T was decreased gradually after injection,and it was much more narrow in group L_0.3 than group L_0.5.When the action of TAPB disappears,ultrasound imaging shew that small amounts of residual injectate in TAP cavity still exist for part of the children.After injectate infiltration,there was obvious thickening and expansion for the black sheath of abdominal internal oblique muscle and transverse abdominal muscle fascia.Conclusion: 1.0.3ml/kg and 0.5ml/kg of 1% lidocaine can provide reliable effects of TAP blockage for inguinal hernia and hydrocele surgery in infants and young children,and reduce the consumption of intraoperative opioids.2.With the progression of time,ultrasound images shew different spreading characteristics after TAP were injected for infants and young children: during injection and the onset tome of local anesthetic solution,the distances of cephalad-caudad and anterior-posterior expansion of local anesthetic solution were increased,and the distance from injectate to rib edg was reduced;however there were no changes for those distance compared postoperation instantly to onset time of TAPB.The volume of injecteate have an obviously effection on its spreading in the TAP.When the volume of injecta increased,the distances of above to mention were expanded,and the distance from the injecta to rib edge was more closer,which may have an advantage to improve the blocking for more higher innervating dermatomal level.Part 2:The effective concentration and effective volume of levobupivacaine in infant and young children ungergoing lower abdominal surgery with TAP blockingObjective: To determine the effective concentration of 0.5ml/kg levobupivacaine and the effective volume of 0.25% levobupivacaine in infants and yong children undergoing low abdominal surgery with ultrasound guided TAP blocking.Methods: 1.100 infants and young children were enrolleded according to inclusive criteria,75 males,25 females,50 children undergoing unilateral inguinal hernia surgery and 50 children undergoing neoplasm resection in low abdominal wall.Patients were randomly divided into five groups: L_0.1,L_0.125,L_0.15,L_0.2 and L_0.25,20 patients in each group.After sevoflurane induction,ultrasound guided TAP blocking were performed,and 0.1%,0.125%,0.15%,0.2% and 0.25% levobupivacaine0.5ml/kg were given respectively by different groups.Then the pinprink tests were performed within T10-L1.If there was body movement,or heart rate or blood pressure increased more than 20% persisting more than 1min during skin incision,TAP was invalid.The general conditions,effective number of TAPB,effective blocking level of TAPB and postoperative analgesic action time were recorded and compared.the EC50,EC95,and 95% confidence interval of 0.5ml/kg levobupivacaine with ultrasound guided TAP blockage were caculated by Probit regression analysis.2.100 infants and young children were selected according to inclusive criteria,77 males,23 females,50 children undergoing unilateral inguinal hernia surgery and 50 children undergoing neoplasm resection in low abdominal wall.Patients were randomly divided into five groups: L_0.2,L_0.25,L_0.3,L_0.35 and L0.4,20 patients in each group.Under ultrasound guided TAP blocking,0.2 ml/kg,0.25 ml/kg,0.3 ml/kg,0.35ml/kg and 0.4 ml/kg 0.25% levobupivacaine were administered respectively by different groups.The other procedure and assessment were as same as part 1.The general conditions,effective number of TAPB,effective blocking level of TAPB and duration if postoperative analgesic action for TAPB were recorded and compared.The EV50,EV95,and 95% confidence interval of 0.25% levobupivacaine ultrasound guided TAP blocking were caculated by Probit regression analysis.Results: 1.The EC50 of 0.5ml/kg levobupivacaine for ultrasound guided TAP blocking was 0.13%?95% confidence interval: 0.118%-0.148%?,and the EC95 was0.23%?95% confidence interval: 0.20%-0.31%?;The equation of Probit dose-effect relationship: Probit=5.84+6.682 X.For children with effective TAPB,there were statistical significance in duration for postoperative analgesia of TAPB between groups?P<0.01?and two different individual groups?P<0.05?.For children with effective TAPB,there were significant positive correlations between the duration of postoperative analgesic action of TAPB and the concentration of levobupivacaine?P<0.01?,and was linear relationship?P<0.01?;the linear equation: duration of postoperative analgesiia=-3.316+68.03 X.2.The EV50 of 0.25% levobupivacaine for ultrasound guided TAP blocking was 0.27ml?95% confidence interval0.248ml-0.284ml?,EV95 was0.37ml?95% confidence interval 0.339ml-0.435ml?;Probit dose-effective equation: Probit=6.57+11.43 X.For children with effective TAPB,there was no statistical significance in duration of postoperative analgesia between groups?P>0.05?.Conclusion: 1.The EC50,EC95 of 0.5ml/kg levobupivacaine for ultrasound guided TAP blocking in infants and children underwent lower abdominal surgery was 0.13%and 0.23% respectively;For children with effective TAPB in defferent groups,there was significant positive linear correlations between the duration of postoperative analgesia of TAPB and the concentration of levobupivacaine.2.The EV50,EV95 of0.25% levobupivacaine fort ultrasound guided TAP blocking in infants and children underwent lower abdominal surgery was 0.27 ml and 0.37 ml respectively.There was no statistical significance in duration of postoperative analgesia for children with effective TAPB between groups.Part 3: The comparision of block effect of ropivacaine between midaxillary line and posterior TAPB technique in infants and young childrenObjective: To compare the analgesic effect of ropivacaine between axillary midline and posterior TAPB technique in infants and young children undergoing lower abdominal surgery.Methods: 60 infants and young children satisfied the inclusion criteria were enrolled,44 males and 16 females;According to TAPB approach,patients were randomly divided into three groups: group A,group B and group C,20 patients in each group.After sevoflurane induction,ultrasound guided TAP blocking were performed with midaxillary line technique in group A and posterior technique in group B,and both injected with 0.25% ropivacaine 0.4 ml;group C was control group,only performed with venipuncture but no TAP.After completion of TAPB,under midazolam sedation,testing the onset time and the blocked dermatomal level of ropivacaine were tested by pinprick.After tests were completed,anesthesias were inducted with sevoflurane inhalation and fellowed by laryngeal mask insertion,Then anesthesia were maintained with 3% sevoflurane;change the dosage of continuous or intermittent infusion of remifentanil according to intraoperative heart rate and blood pressure changes.Record the general condition,the duration of operation and anesthesia,the time of laryngeal mask removing and the duration of children in PACU for all groups.The onset time and the blocked dermatomal level of TAPB were recorded for group A and B.The changes of blood pressure and heart rate before and after skin incision were observed and the total consumpion of intraoperative remifentanil were calculated;The agitation score were recorded and the degree of agitation were evaluated in PACU;FLACC scores of 2h,4h,8h,12 h,16 h and 24 h postoperatively were evaluated.The complications related with procedure of of TAP blockage and the adverse reactions of local anesthetic were Observed.Follow-up24 h after surgery,record the occurrence of adverse reactions such as nausea and vomiting,dizziness,headache,heart palpitations,respiratory depression and sleepiness.Results: the onset time of group A and group B were?12±2.10?min and?11.6±2.08?min,there was no statistical significance between the two groups?P>0.05?;The blocked dermatomal level of group A reached down to L1 nerve plane and up to T10 nerve plane,and group B reached down to L1 nerve plane and up to T9-7 nerve plane.There was no statistical difference between the three groups in average blood pressure and heart rate before and after skin incision;the total consumpion of intraoperative remifentanil in group A and group B were less than control group?P< 0.01?;During staying in PACU,agitation rate and PAED score were less in group A and group B than control group?P < 0.05?;FLACC scores for 2 h,4 h,8 h and 12 h after postoperation in group A and group B were significantly lower compared with control group?P < 0.05?;postoperative 16 h FLACC score of group B were significantly lower compared with group A and group C?P < 0.05?.Conclusion: midaxillary line and posterior TAPB technique with 0.25% ropivacaine0.4 ml can provide satisfied analgesia for infants and young children undergoing lower abdominal surgery;The onset time was comparable between two techniques,but posterior TAPB can provide higher blocking range and longer duration of postoperative analgesia which is obviously better than that of the midaxillary line approach;Both methods can significantly reduce the intraoperative consumption of remifentanil,decrease the agitation incidence during anesthesia recovery period.