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 Table of Contents  
ORIGINAL ARTICLE
Year : 2018  |  Volume : 16  |  Issue : 4  |  Page : 405-413

Comparative study between the analgesic effects of transversus abdominis plane block and caudal block in lower abdominal surgeries in pediatrics compared with general anesthesia


1 Department of Anesthesia and Intensive Care, Faculty of Medicine, Al-Azhar University, Alhussein University Hospital, Cairo, Egypt
2 Department of Clinical Pathology, Faculty of Medicine, Al-Azhar University, Alhussein University Hospital, Cairo, Egypt
3 Department of Anesthesia, Banha Kids Hospital, Banha, Egypt

Date of Submission26-Nov-2018
Date of Acceptance27-Jan-2019
Date of Web Publication23-Apr-2019

Correspondence Address:
Ismail F Ezz
Department of Anesthesia and Intensive Care, Faculty of Medicine, Al-Azhar University, Alhussein University Hospital, Cairo, 11727
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/AZMJ.AZMJ_129_18

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  Abstract 


Background Pain experienced after abdominal surgery is derived from abdominal wall incision. Transversus abdominis plane (TAP) block is a novel approach for blocking abdominal wall neural afferents.
Aim of study To evaluate the analgesic effects of ultrasound-guided TAP block and caudal block in lower abdominal surgeries in pediatrics compared with general anesthesia (GA).
Patients and methods This prospective, randomized, controlled, single-blinded study was conducted on 60 pediatric patients of the American Society of Anesthesiologists physical status I and II, aged 2–6 years. Patients were randomized into three equal groups. Groups I and II received ultrasound-guided TAP and caudal block, respectively, whereas group III received GA and opioid analgesia. The primary outcome was intraoperative analgesic effects manifested by changes in hemodynamics and catecholamines. Secondary outcomes included postoperative analgesia and complications.
Results There was a highly significant decrease in heart rate 5 min after skin incision in both TAP and caudal groups compared with the GA group. However, there were nonsignificant differences between groups as regards systolic and diastolic blood pressures at baseline and 5 min after skin incision. There was a highly significant decrease in both norepinephrine and epinephrine in TAP and caudal groups compared with the GA group at 5 min after skin incision. Similar findings were reported 60 min after recovery. Postoperatively, Face, Legs, Activity, Cry, Consolability values were significantly higher in the caudal group compared with the GA and TAP groups. The side effects were statistically higher in the GA group. Till 12 postoperative hours the patients who received the TAP block did not require analgesic medication compared to the seven patients who received the caudal block. Patients who received GA significantly required analgesia after 4 h postoperatively.
Conclusion Ultrasound-guided TAP block is a good option for providing intra- and postoperative analgesia with no side effects in children undergoing lower abdominal surgeries.

Keywords: catecholamine, caudal anesthesia, general anesthesia, lower abdominal surgeries, pain, pediatrics, transversus abdominis plane block


How to cite this article:
Ezz IF, Alaa SM, Ahmed AAF, Kareem AA. Comparative study between the analgesic effects of transversus abdominis plane block and caudal block in lower abdominal surgeries in pediatrics compared with general anesthesia. Al-Azhar Assiut Med J 2018;16:405-13

How to cite this URL:
Ezz IF, Alaa SM, Ahmed AAF, Kareem AA. Comparative study between the analgesic effects of transversus abdominis plane block and caudal block in lower abdominal surgeries in pediatrics compared with general anesthesia. Al-Azhar Assiut Med J [serial online] 2018 [cited 2019 Aug 20];16:405-13. Available from: http://www.azmj.eg.net/text.asp?2018/16/4/405/256746




  Introduction Top


The key to success in pediatric day-case surgery is proper patient selection, prevention of common postoperative complications, and adequate pain management. Severe postoperative pain not only decreases the patients’ functional capacity but also is associated with longer postoperative stay and higher incidence of unanticipated readmission. Hence, adequate pain management is mandatory in day-case surgery and is receiving greater attention [1].

A child’s pain does not influence only the child, but also the family. Families can be a source of support for children in postoperative pain. The child’s pain also increases stress in the family members [2].

Transversus abdominis plane (TAP) block is a novel approach for blocking the abdominal wall neural afferents via the bilateral lumbar triangles of Petit. McDonnell et al. [3] described the use of TAP block for analgesia after major midline lower bowel surgery. TAP block provides effective alternative analgesia when an epidural is contraindicated or refused. The problem with a blind technique is the plane is identified by the ‘pop’ sensation of a blunt needle passing through fascial planes, which is a subtle and imprecise endpoint.

Pain experienced by patients after abdominal surgery is derived from the abdominal wall incision. The abdominal wall consists of three muscle layers, external oblique, internal oblique, and transversus abdominis; and their associated fascial sheaths. The central abdominal wall also includes the rectus abdominis muscles and its associated fascial sheath. This muscular wall is innervated by nerve afferents that course through the transversus abdominis neurofascial plane [4].

The current approaches to the blockade of these nerve afferents, such as abdominal field blocks, are limited, and the degree of block achieved can be unpredictable. A major reason for the relative lack of efficacy of these blocks is the lack of clearly defined anatomic landmarks, leading to uncertainty regarding the exact needle positioning, and the lack of a clear indication that the local anesthetic is being deposited in the correct anatomical plane [5],[6].

Netter [4] has sought an alternative, reliable approach to the blockade of the neural afferents to the anterior abdominal wall. These neural afferents course through the neurofascial plane between the internal oblique and the transversus abdominis muscles. His group identified the lumbar triangle of Petit as a potential access point to this neurofascial plane. This triangle is bounded posteriorly by the latissimus dorsi muscle and anteriorly by the external oblique, with the iliac crest forming the base of the triangle and is a fixed and easily palpable landmark. By introducing local anesthetics into the TAP via the triangle of Petit, it is possible to block the sensory nerves of the anterior abdominal wall before they pierce the musculature to innervate the abdomen. They call this novel block the TAP block.

The aim of the study was to evaluate the analgesic effects of ultrasound-guided TAP block and caudal block in lower abdominal surgeries in pediatrics compared with general anesthesia (GA). The primary outcome was intraoperative analgesic effects manifested by changes in hemodynamics and catecholamines. Secondary outcomes included postoperative analgesia and complications.


  Patients and methods Top


Sixty healthy pediatric patients, classified as the American Society of Anesthesiologists physical status I and II, aged 2–6 years, were included in this prospective, randomized, single-blinded, and controlled study. After approval by the ethics committee of the Faculty of Medicine, Al-Azhar University and provision of written informed consent from children’ parents, sixty healthy pediatric patients. All patients were scheduled for lower abdominal surgeries treated as day-case surgery.

Exclusion criteria included

  1. Patient/parent refusal.
  2. Patients with bilateral, obstructed, or strangulated hernias.
  3. Patients in whom a caudal block is contraindicated (infection at the site of block, bleeding diathesis, preexisting neurological, or spinal disease or abnormalities of the sacrum).
  4. Patients with a history of allergic reactions to local anesthetics.


Preoperative evaluation

The patients were screened for suitability by:
  1. History from parents about common cold, wheezy chest, cough and expectoration, fever and congenital anomalies.
  2. Physical examination included chest and heart auscultation, and examination of the back especially the sacral area.
  3. Investigations included complete blood picture, coagulation profile, and chest radiography.


Anesthetic technique

Preoperative sedation with nasal drops of midazolam (0.5 mg/kg). After 15 min the patients were taken to the operating room (OR) where standard American Society of Anesthesiologists monitors were placed (pulse oximetry, noninvasive blood pressure cuff, and EKG). Inhalation induction with sevoflurane was used and followed by intravenous cannulation using 22 or 24 G cannula. Thereafter, laryngeal mask airway of appropriate size was inserted to secure the airway. Anesthesia was maintained with sevoflurane in oxygen/air mixture and spontaneous breathing.

RandomizationThe patients were randomly allocated to one of the three groups according to a computer-generated table. A sealed envelope with the study technique to be used was given to the anesthesiologist on the morning of surgery

  • Group 1: received caudal bupivacaine 0.25% (1 m/kg) guided with ultrasound after general inhalational anesthesia.
  • Group 2: received 0.5 ml/kg bupivacaine 0.25% as TAP block guided with ultrasound after general inhalational anesthesia.
  • Group 3: this group received only general inhalational anesthesia with intravenous opioid analgesia (fentanyl 1–2 μg/kg).


Surgery was started 15 min after caudal or TAP block.

Performance of the transversus abdominis plane block

TAP blocks were performed with the patients in the supine position. The operative side was confirmed for each patient and marked for the TAP block. A wide-band high-frequency (5–13 MHz) linear array transducer (12 L-SC, GE Venue 40 point of care ultrasound machine; GE Healthcare, , Chicago, Illinois, USA) was used for all blocks ([Figure 1]). All blocks were performed using a 21 G (100 mm) SonoPlex echogenic needles by Pajunk (Norcross, Georgia, USA) ([Figure 2]). Strict aseptic technique was used during the procedure.
Figure 1 GE Venue 40 point of care ultrasound machine (GE Healthcare).

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Figure 2 SonoPlex echogenic needle by Pajunk (21 G, 100 mm).

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The ultrasound probe was placed in the midaxillary line of the side to be blocked, midway between the lower costal margin and the iliac crest. Scanning of the lateral abdominal wall was done by sliding the probe anteriorly and posteriorly to appreciate the three muscular layers forming the abdominal wall: from superficial to deep; external oblique, internal oblique, and transversus abdominis ([Figure 3]).
Figure 3 Muscular layers forming the abdominal wall with the transversus abdominis plane between the internal oblique and transversus abdominis muscles.

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The needle was advanced from the anterior aspect of the abdomen posteriorly using the in-plane approach. Ultrasound-guided TAP block was performed behind the anterior axillary line between the iliac crest and the most inferior extent of the ribs. The plane between internal oblique and transversus was located around the anterior axillary line while the probe is positioned transverse to the abdomen. Normal saline was used for hydrodissection till the tip of the needle is properly identified in the TAP ([Figure 4]) between the internal oblique (superficial) and transversus abdominis (deep).
Figure 4 Needle tip appears in the transversus abdominis plane between the internal oblique and transversus abdominis (in-plane approach):EO, external oblique muscle; IO, internal oblique muscle; TA, transversus abdominis muscle.

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After negative aspiration, 0.5 ml/kg (bupivacaine 0.25%) was injected in small increments over few minutes observing the spread dissection of the fluid between the two appropriate muscles ([Figure 5]).
Figure 5 Injection of the local anesthetic appears in the transversus abdominis plane between the internal oblique and transversus abdominis. EO, external oblique muscle; IO, internal oblique muscle; TA, transversus abdominis muscle; LA, local anesthetic.

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Intraoperative data

  1. Vital signs (heart rate, systolic and diastolic blood pressures, respiratory rate, and temperature). Baseline values were taken 5 min after induction of anesthesia.
  2. Oxygen saturation and capnography.
  3. Response to surgical stimulation (movement).
  4. Stress hormones, catecholamines: venous blood samples were taken at the following times:
    1. 5 min after induction: epinephrine-1 and norepinephrine-1.
    2. 5 min after skin incision: epinephrine-2 and norepinephrine-2.
    3. At the end of surgery: epinephrine-3 and norepinephrine-3.


Postoperative data

  1. Vital signs including heart rate, blood pressure, respiratory rate, temperature, and oxygen saturation.
  2. Evaluation of analgesic efficacy: After the child was awake, a blinded independent observer assessed pain at 1, 2, 4, 6, 8, and 12 h using the Face, Legs, Activity, Cry, Consolability (FLACC) scale [7]. The quality of analgesia was considered good at a pain score of 3 or less.
  3. Assessment of need for postoperative analgesia up to 12 h. Rescue analgesia included paracetamol intravenously (15 mg/kg).
  4. Venous blood samples for catecholamine were taken 60 min after recovery or with the first analgesic administration whichever comes first (epinephrine-4 and norepinephrine-4).
  5. Monitoring of drugs’ safety by determination of incidence of nausea and vomiting, hypotension, bradycardia, urine retention, dry mouth, and itching during 12 postoperative hours.


Statistical analysis

Data were coded and entered using the statistical package SPSS, version 22 (SPSS Inc., Chicago, Illinois, USA). Data were summarized using mean and SD for normally distributed quantitative variables, and comparisons between groups were done using analysis of variance followed by post-hoc test if there is significance. Qualitative data were presented as frequencies and percentages, and χ2 test was used to compare among the three groups. The significance level was set at a P value of less than or equal to 0.05.


  Results Top


Out of the 60 patients, 47 (78.3%) patients were men and 13 (21.7%) patients were women. Statistically, there was a highly significant difference between the studied groups according to the type of operation ([Table 1]).
Table 1 Comparison between the studied groups as regards age, sex, and type of operation

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There was a highly significant decrease in heart rate 5 min after skin incision in both TAP and caudal groups compared with the GA group. However, there were nonsignificant differences between groups as regards systolic and diastolic blood pressures at baseline and 5 min after skin incision ([Table 2]).
Table 2 Comparison between the studied groups according to heart rate, systolic and diastolic blood pressures at baseline and 5 min after skin incision

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Five minutes after skin incision, there was a highly significant decrease in both norepinephrine and epinephrine in TAP and caudal groups compared with the GA group. Similar findings was reported 60 min after recovery ([Table 3]).
Table 3 Comparison between the studied groups according to norepinephrine and epinephrine (pg/ml) in different follow-up periods

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Postoperatively, FLACC values were significantly higher in the caudal group compared with GA and TAP groups ([Table 4]).
Table 4 Comparison between the studied groups according to Face, Legs, Activity, Cry, Consolability score in different follow-up periods

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Side effects were statistically higher in the GA group (nausea, vomiting, and hypotension) compared with the other two groups ([Table 5]).
Table 5 Incidence of side effects between the studied groups

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Patients who received TAP block did not require analgesic medication up to 12 h postoperatively ([Table 6]). Meanwhile, only seven patients who received the caudal block required analgesia after 12 h postoperatively with a highly significant difference compared with the other two groups. Patients in the GA group significantly required analgesia after 4 h postoperatively.
Table 6 Comparison between the studied groups according to first analgesic administration

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  Discussion Top


Postoperative pain management is one of the most important issues influencing the outcome of surgery. Postoperative pain, especially when poorly controlled, results in harmful acute effects such as adverse physiological responses and chronic effects like delayed long-term recovery and chronic pain. Thus, techniques to provide postoperative analgesia have become an integral part of pediatric anesthesia practice [8].

Of the various modalities available for postoperative pain relief, regional anesthesia, especially caudal block is being used with greatest frequency in pediatric patients. The safe and effective use of caudal block for providing intraoperative and postoperative analgesia has been established by Tobias [9]. However, there is a trend toward the use of peripheral nerve blockade wherever applicable, given the lower incidences of adverse effects when compared with neuraxial techniques.

Of the various peripheral nerve block techniques available, the TAP block is a new and rapidly evolving peripheral nerve block technique that provides effective analgesia during the postoperative period following lower abdominal surgeries [10]. Taylor et al. [11] have also shown that TAP block is a good analgesic alternative for lower abdominal or pelvic surgical procedures.

The intraoperative and postoperative analgesic efficacy of the TAP block has been successfully described in adult patients undergoing abdominal surgeries such as colonic resection, total abdominal hysterectomy, and appendectomy [12].

A study on children have been done by Fredrickson [13] who concluded that the use of TAP block is a good alternative in pediatric patients for postoperative pain management in lower abdominal and infraumbilical surgeries.

There is a paucity of literature regarding comparison of ultrasound-guided TAP block and caudal block in terms of duration of postoperative analgesia in children undergoing abdominal surgeries. So, the aim of the present study was to evaluate the analgesic effects of the TAP block and caudal epidural administration in lower abdominal surgeries in pediatrics when guided with ultrasound compared with GA.

Out of the 60 patients participated in the present study, 47 (78.3%) patients were men and 13 (21.7%) patients were women.

Kanojia and Ahuja [14] evaluated TAP block and caudal block for the duration and quality of analgesia postoperatively in children. The mean age of their patients in group TAP was 6.81±2.82 years whereas in group caudal was 5.32±2.91 years. All children weighed less than or equal to 25 kg. The children in both groups were comparable regarding age, weight, and duration of surgery. The number of children who underwent the different types of operations in both groups was also comparable. Surgical procedures included herniotomy (group TAP n=29, group caudal n=29) and orchidopexy (group TAP n=1, group caudal n=1).

As regards hemodynamics, there was a highly significant decrease in heart rate 5 min after skin incision in both TAP and caudal groups compared with the GA group. Kanojia and Ahuja [14] found that intraoperative hemodynamic parameters (heart rate and mean arterial pressure) were within the normal limits and did not show any significant increase (>20%) from the baseline values.

In the present study, there was a highly significant decrease in both norepinephrine and epinephrine levels 5 min after skin incision in both TAP and caudal groups compared with the GA group. Similar findings were reported 60 min after recovery denoting the proper analgesic effects produced by such techniques.

Postoperatively, we found that FLACC values were significantly higher in the caudal group compared with GA and TAP groups. This may be due to the highly significant difference between the studied groups according to the type of operation, as there were many patients subjected to orchidopexy in the caudal group compared with the other two groups with a relatively more pain exhibited by such operations.

Tobias [9] demonstrated safe and effective use of ultrasound-guided TAP block in 10 pediatric patients in age ranging from 10 months to 8 years, undergoing umbilical and lower abdominal surgeries with 0.3 ml/kg of 0.25% bupivacaine and 1 : 200 000 epinephrine. He reported effective postoperative analgesia in eight out of 10 patients with the first request for postoperative analgesia varying from 7 to 11 h which are consistent with our results.

In the present study, the patients who received the TAP block did not require analgesic medication up to 12 h postoperatively. Meanwhile, only seven patients who received caudal block requested their first rescue analgesic after 12 h postoperatively.

Kanojia and Ahuja [14] found that the mean time for requirement of rescue analgesia in group TAP was 7.41±0.78 h whereas in group caudal it was 5.07±0.69 h. The difference was statistically significant between the two groups, the earliest need for rescue analgesia being in group caudal which is comparable to our results.

Falmer et al. [15] used ultrasound-guided TAP block in children undergoing upper and lower abdominal surgeries indicated a sensory blockade of usually three to four dermatomes and they suggested that the TAP block should be offered for lower abdominal surgery only.

In agreement with our results, Ahmed and Rayanb [16] evaluated the analgesic efficacy of an ultrasound-guided TAP block and compared it with a caudal block in children undergoing day-surgery unilateral open herniotomy. They concluded that the ultrasound-guided TAP block is as effective as the caudal block in providing intraoperative and postoperative analgesia in day-case open inguinal hernia repair in children.Contrary to our results, Sethi et al. [17] compared the efficacy of caudal epidural block versus ultrasonography-guided TAP block for providing postoperative pain relief in children scheduled for lower abdominal surgery. They concluded that caudal epidural block provides a significantly prolonged duration of postoperative analgesia when compared with ultrasonography-guided TAP block.

In our study, side effects were statistically higher in the GA group (nausea, vomiting, and hypotension) compared with the other two groups. Kanojia and Ahuja [14] reported no complications in their studied groups. Tsui and Suresh [18] postulated that ultrasound, primarily used during the performance of upper extremity and trunk blocks, may reduce complications such as mechanical nerve injury and arterial, pleural, or peritoneal puncture.


  Conclusion Top


Ultrasound-guided TAP block is a good option for providing intraoperative and postoperative analgesia with no side effects in children undergoing lower abdominal surgeries. The duration of analgesia was significantly longer in children who received the TAP block compared with caudal block and GA.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Gold J, Townsend J, Juy D, Kant A, Gallardo C, Joseph M. Current trends in pediatric pain management: from precoperative to the postoperative bedside and beyond. Semin Anesth Perioperat Med Pain 2006; 25:159–171.  Back to cited text no. 1
    
2.
Kankkunen P, Pietila AM, Julkunen KV. Families, and children’s postoperative pain − literature review. J Pediatr Nurs 2004; 19:2.  Back to cited text no. 2
    
3.
McDonnell JG, O’donnell B, Curley G, Heffernan A, Power C, Laffey JG. The analgesic efficacy of transversus abdominis plane block after abdominal surgery: a prospective randomized controlled trial. Anesth Analg 2007; 104:193–197.  Back to cited text no. 3
    
4.
Netter FH. Back and spinal cord. In: Netter FH, ed. Atlas of human anatomy summit. New Jersey, USA: The Ciba-Geigy Corporation; 1989. 145–155  Back to cited text no. 4
    
5.
Dierking GW, Dahl JB, Kanstrup J, Dahl A, Kehlet H. Effect of pre- vs post-operative inguinal field block on postoperative pain after herniorrhaphy. Br J Anaesth 1992; 68:344–348.  Back to cited text no. 5
    
6.
Kuppuvelumani P, Jaradi H, Delilkan A. Abdominal nerve blockade for postoperative analgesia after caesarean section. Asia Oceania J Obstet Gynaecol 1993; 19:165–169.  Back to cited text no. 6
    
7.
Merkel SI, Voepel-Lewis T, Shayevitz JR, Malviya S. The FLACC: a behavioral scale for scoring postoperative pain in young children. Pediatr Nurse 1997; 23:293–297.  Back to cited text no. 7
    
8.
Hurley RW, Wu CL. Acute post operative pain. In Miller RD, ed. Miller’s anaesthesia. 7th ed. Philadelphia, PA: Churchill Livingstone 2009. 2757–2758  Back to cited text no. 8
    
9.
Tobias JD. Preliminary experience with transversus abdominis plane block for post operative pain relief in infants and children. Saudi J Anaesth 2009; 3:2–6.  Back to cited text no. 9
    
10.
Jankonic Z. Transversus abdominis plane block: the holygrail of anaesthesia for (lower) abdominal surgery. Periodicum Biologorum 2009; 3:203–208.  Back to cited text no. 10
    
11.
Taylor R Jr, Pergolizzi JV, Sinclair A, Raffa RB, Aldington D, Plavin S, Apfel CC. Transversus abdominis block: clinical uses, side effects, and future perspectives. Pain Pract 2013; 13:332–344.  Back to cited text no. 11
    
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Niraj G, Searle A, Mathews M, Misra V, Baban M, Kiani S, Wong M. Analgesic efficacy of ultrasound guided transversus abdominis plane block in patients undergoing open appendicectomy. Br J Anaesth 2009; 103:601–605.  Back to cited text no. 12
    
13.
Fredrickson MJ. Ultrasound (US) guided transversus abdominis plane (TAP) block for paediatric inguinal hernia surgery-a pilot study. Paediatr Anaesth 2009; 19:556–557.  Back to cited text no. 13
    
14.
Kanojia N, Ahuja S. Comparison of transversus abdominis plane block and caudal block for postoperative analgesia in children undergoing lower abdominal surgery. Int J Sci Res 2015; 4:1585–1587.  Back to cited text no. 14
    
15.
Falmer GM, Luk VHY, Smith R, Prentice EK. Audit of initial use of the ultrasound guided transversus abdominis plane block in children. Anesth Intensive Care 2011; 39:279–286.  Back to cited text no. 15
    
16.
Ahmed AA, Rayanb AA. Ultrasound-guided transversus abdominis plane block versus caudal block for postoperative analgesia in children undergoing unilateral open inguinal herniotomy: a comparative study. Ain-Shams J Anesthesiol 2016; 9:284–289.  Back to cited text no. 16
    
17.
Sethi N, Pant D, Dutta A, Koul A, Sood J, Chugh PT. Comparison of caudal epidural block and ultrasonography-guided transversus abdominis plane block for pain relief in children undergoing lower abdominal surgery. J Clin Anesth 2016; 33:322–329.  Back to cited text no. 17
    
18.
Tsui BC, Suresh S. Ultrasound imaging for regional anesthesia in infants, children, and adolescents. a review of current literature and its application in the practice of extremity and trunk blocks. Anesthesiology 2010; 112:473–492.  Back to cited text no. 18
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]



 

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