|Year : 2020 | Volume
| Issue : 2 | Page : 167-175
Ultrasound-guided quadratus lumborum block versus transversus abdominis plane block in children undergoing laparoscopic appendectomy: a randomized controlled study
Shereen E Abd Ellatif, Fatma M Ahmed
Department of Anaesthesia and Surgical Intensive Care, Faculty of Medicine, Zagazig University, Zagazig, Egypt
|Date of Submission||27-Aug-2019|
|Date of Acceptance||28-Sep-2019|
|Date of Web Publication||27-Jun-2020|
MD Shereen E Abd Ellatif
El Shimaa Street, Alqawmia, Zagazig, Al Sharqia Governorate, 44511
Source of Support: None, Conflict of Interest: None
Context Ultrasound (US)-guided quadratus lumborum block (QLB) is a new abdominal truncal block used for perioperative pain management of both upper and lower abdominal surgeries.
Aims To compare the analgesic efficacy of US-guided QLB with transversus abdominis plane (TAP) block.
Settings Approval of Zagazig Institutional Review Board (IRB) was obtained (ZU-IRB # 5504/16-9-2018) before the study, and patient’s informed written consent was also obtained. Our clinical study was registered with ClinicalTrials.gov (NCT04031196). A total of 34 pediatric patients scheduled for elective laparoscopic appendectomy were randomly allocated in two equal groups: QLB and TAP block groups.
Patients and methods All patients received general anesthesia using intravenous 2 mg/kg propofol, 1 µg/kg fentanyl, and atracurium 0.5 mg/kg. After induction of anesthesia, QLB group received bilateral US-guided QLB type 2, using 0.5 ml/kg of 0.25% levobupivacaine, whereas TAP block group received bilateral US-guided TAP block using 0.5 ml/kg of 0.25% levobupivacaine. The primary outcomes were changes of intraoperative hemodynamics and postoperative pain assessment. Secondary outcomes were total intraoperative fentanyl consumption, the first time of rescue analgesics, total rescue analgesic consumption in the first postoperative 24 h, and degree of parent satisfaction.
Results QLB group had statistically significant lower hemodynamic changes 15 min after performing the block to the end of surgery (P<0.05), highly significant lower visual analog scale score in the first postoperative 4 h (P<0.001), highly significant lower intraoperative fentanyl dose (P<0.001), significant longer time for the first rescue analgesic, lower analgesic doses given in the first 24 h postoperatively (P<0.001), and higher parent satisfaction compared with TAP block group.
Conclusion This study revealed that QLB provides longer and more effective postoperative analgesia compared with TAP block in pediatric patients undergoing laparoscopic appendectomy.
Keywords: appendectomy, laparoscopic, pediatric, quadratus lumborum block, regional anesthesia, transversus abdominis plane
|How to cite this article:|
Abd Ellatif SE, Ahmed FM. Ultrasound-guided quadratus lumborum block versus transversus abdominis plane block in children undergoing laparoscopic appendectomy: a randomized controlled study. Res Opin Anesth Intensive Care 2020;7:167-75
|How to cite this URL:|
Abd Ellatif SE, Ahmed FM. Ultrasound-guided quadratus lumborum block versus transversus abdominis plane block in children undergoing laparoscopic appendectomy: a randomized controlled study. Res Opin Anesth Intensive Care [serial online] 2020 [cited 2020 Jul 7];7:167-75. Available from: http://www.roaic.eg.net/text.asp?2020/7/2/167/288000
| Introduction|| |
Recently, laparoscopic appendectomy has been successfully used instead of the traditional open method . However, patients may require hospitalization for over 24 h owing to postoperative pain caused by the surgical wound and visceral peritonitic pain of peritoneal inflammation and infection . Regional anesthesia techniques such as the transversus abdominis plane (TAP) block are enhanced for pain management in pediatric lower abdominal surgery as it blocks sensory nerves that supply the anterior abdominal wall . It was first described in 2004 by McDonnell et al. ; later ultrasound (US)-guided technique was popularized by Hebbard et al. .
Quadratus lumborum block (QLB) was initially described by Blanco, where the LA was injected at the anterolateral aspect of the QL muscle (type 1). Later, Børglum injected the LA at the anterior aspect of the QL (type 3). Recently, Blanco injected the LA at the posterior aspect of the QL muscle (type 2), and finally the intramuscular QLB (type 4) was introduced, where the LA is injected directly into the QL muscle . QLB has been recently described for management of chronic pain following abdominal hernia repair and postoperative pain following abdominal surgery .
The aim of this study was to compare the effect of US-guided QLB type 2 versus classic TAP block on hemodynamic stability and the degree of pain relief in pediatric patients undergoing laparoscopic appendectomy.
| Patients and methods|| |
This prospective randomized clinical study was conducted in Zagazig University Hospitals from October 2018 to June 2019. Approval of Zagazig Institutional Review Board (IRB) was obtained (ZU-IRB # 5504/16-9-2018) before the study, and patient’s informed written consent was also obtained. Our clinical study was registered with ClinicalTrials.gov (NCT04031196).
The sample size was calculated to be 34 cases divided into two groups, with 17 patients in each group. It was calculated using open Epi program, at confidence interval of 95% and power of test 80%, assuming that the total intraoperative fentanyl dose was 0.8±0.5 and 1.4±0.7 in TAP block and control groups, respectively .
Children 7–12 years old, 20–35 kg body weight, with American Society of Anesthesiologist status I–II, scheduled for laparoscopic appendectomy were involved in this study. Patients refusing regional anesthesia, those with bleeding disorders, skin lesion at needle insertion site, sepsis, liver disease, and peritonitis were excluded from the study.
Computer-generated table randomly allocated 34 patients into two equal groups, ‘QLB group’ and ‘TAP block group’, with 17 patients in each one. The patient was trained to report the level of pain on visual analog scale (VAS) from 0–10 (where 0 indicates no pain and 10 indicates the most severe pain). After insertion of venous access, all patients received 0.01 mg/kg atropine as a premedication. Preoperative monitoring and baseline readings of mean arterial blood pressure (MAP) and heart rate (HR) were recorded.
In either group, general anesthesia was induced using 1.5–2 mg/kg propofol, 1 µg /kg fentanyl, and atracurium 0.5 mg/kg for endotracheal intubation. Isoflurane (1 MAC) was used to maintain anesthesia in oxygen/air mixture. Muscle relaxation was maintained using atracurium supplement 0.1 mg/kg every 30 min. Parameters of mechanical ventilation were adjusted to maintain an end-tidal CO2 ∼35–40 mmHg.
In QLB group, the patient was placed in the lateral decubitus position. After sterilization of the US site, needle entry, and draping, a low frequency convex probe of Sonosite M Turbo US (FUJIFIM Sonosite Inc., Bothell, Washington, USA) was placed horizontally in the anterior axillary line midway between the subcostal margin and the iliac crest to identify the triple abdominal muscle layers. Then, the probe was moved posteriorly to the posterior axillary line until the QL muscle was visualized with its attachment to the lateral edge of the transverse process of the L4 vertebral body, the psoas major muscle placed anteriorly, and the erector spinae muscle posteriorly; this is a well-recognizable pattern of a shamrock sign with three leaves . A 22-G, 80-mm needle (Stimuplex D, B-Braun, Germany) was inserted in plane relative to the US probe, into the posterior aspect of the QL muscle (between QL and erector spinae muscle); this is known as QLB type 2. Then, 0.5 ml/kg of 0.25% levobupivacaine was injected behind the muscle as a bolus dose ([Figure 1]a). The block was performed bilaterally.
|Figure 1 (a) Ultrasound images of quadratus lumborum block (QLB) type 2, and (b) classic transversus abdominis plane (TAP) block.|
Click here to view
In TAP block group, the patient was placed in the supine position, and after sterilization, a linear high frequency probe of Sonosite M Turbo US (FUJIFIM Sonosite Inc.) was placed posterior to the midaxillary line at the midpoint between the inferior costal margin and the iliac crest. US identification of the plane between the internal oblique and the transversus abdominis muscle was followed by inserting the needle in plane technique relative to US probe, between the two muscles; this is known as classic TAP block. Then, LA was injected in a bolus dose 0.5 ml/kg of 0.25% levobupivacaine, the TAP was appeared expanding with the injection (appeared as a hypoechoic space) ([Figure 1]b); the block was done bilaterally .
Intravenous fentanyl (0.5 µg/kg) was given intraoperatively when any increase in MAP or HR more than 20% of baseline data occurred throughout the procedure. At the end of the surgery, anesthesia was discontinued, reversal of muscle relaxation by 0.02 mg/kg atropine and 0.05 mg/kg prostigmine was done, and patients received 1 mg/kg diclofenac sodium suppository before extubation.
Patients were assessed in the immediate postoperative period and then at 2, 4, 6, 8, 12, 18, and at 24 h for the quality of analgesia using VAS score. Patients were given paracetamol 15 mg/kg intravenous as a rescue analgesic if VAS score was more than or equal to three.
The patients and the investigators who were responsible for assessing the primary and secondary outcomes were blinded to study group assignment. However, the attending intraoperative anesthesiologists and assessors were not blinded to study group assignment.
The primary outcomes were changes in intraoperative hemodynamic measures; mean arterial blood pressure and heart rate(MAP and HR) (measured at baseline (To), 10 min after intubation and before performing the block (T1), 15 min after performing the block (T2) and the mean of intraoperative values measured every 15 min till the end of the surgery (T3))and degree of pain assessed by VAS scale. Secondary outcome items were total intraoperative fentanyl consumption, the first time of rescue analgesics, total amount of rescue analgesic consumed in the first postoperative 24 h, length of hospitalization, postoperative nausea and vomiting, and degree of patient and parent satisfaction based on a five-point assessment scale (satisfied or completely satisfied, not satisfied nor dissatisfied, dissatisfied, and completely dissatisfied) .
The collected data were statistically analyzed using statistical package for social science software (version 20; SPSS Inc., Chicago, Illinois, USA). Continuous variables with a normal distribution were reported as mean±SD and range. Categorical variables were summarized as frequencies and percentages. Numerical data were evaluated using independent t test and analysis of variance for repeated measures, whereas nonnumerical data were evaluated by χ2 test. P values less than 0.05 and less than 0.001 were considered statistically significant and highly statistical significant, respectively.
| Results|| |
A total of 42 patients scheduled for laparoscopic appendectomy were assessed for eligibility to participate in this study. Of them, eight patients were excluded, four patients refused to participate, and the other four had one or more of the exclusion criteria; therefore, the remaining 34 patients were included in the study ([Figure 2]).
As shown in [Table 1], there was no statistically significant difference (P>0.05) between QLB and TAP block groups regarding age, sex, weight, American Society of Anesthesiologist physical status (I/II), and operative time, ensuring homogeneity of both groups.
|Table 1 Demographic and clinical characteristics of the studied groups (N=34)|
Click here to view
For hemodynamic changes (MAP and HR), both were comparable at baseline reading (T0) and 10 min after intubation and before performing the block (T1), and then became statistically significantly lower (P<0.05) in the QLB group 15 min after performing the block (T2) and intraoperatively till the end of the surgery (T3). Moreover, changes within each group were statistically significant before and after the block (P<0.05), but all were within the clinically accepted range ([Figure 3]a and b).
|Figure 3 Intraoperative hemodynamic changes (mean arterial pressure and heart rate) between the studied groups (N=34).|
Click here to view
Regarding the total intraoperative fentanyl dose, it was highly significantly lower in QLB group compared with TAP block group (P<0.001). Moreover, the first time to rescue analgesic was longer, and the total paracetamol/24 h dose was less in QLB group compared with TAP block group (P<0.001), whereas the duration of hospital stay and postoperative nausea and vomiting were comparable between both groups, with no statistically significant difference (P=0.128 and 0.289, respectively) ([Table 2]).
|Table 2 Intraoperative and postoperative findings between the studied groups (N=34)|
Click here to view
In the first postoperative 4 h, the VAS score mean values were highly statistically significant lower (P<0.001) for QLB group compared with TAP block group. However, pain scores at the remaining time intervals were not statistically significant different between both the groups ([Figure 4]).
|Figure 4 Mean postoperative visual analog scores (VAS) between the studied groups (N=34).|
Click here to view
When comparing parents’ and patients’ satisfaction between both groups, there was significantly higher satisfaction in the QLB group (P=0.016) ([Table 2]).
| Discussion|| |
Pain management after laparoscopic appendectomy is required. Several regional anesthesia procedures have been described for this purpose to reduce opiate requirements while producing an effective pain relief . QLB is recently considered as one of the pain control procedures for abdominal surgeries in both adults and children .
The current randomized study demonstrated that bilateral US-guided QLB gives an additive value to perioperative pain management strategy in children undergoing laparoscopic appendectomy in comparison with the conventional TAP block that provides satisfactory somatic block with no or minimal visceral analgesia (the localized effects of the TAP block have a minor contribution to the pain control compared with analgesia achieved by extension of LA into paravertebral space).
QLB is not technically difficult to be done as it is a superficial fascial block between the posterior abdominal wall muscles (QL and erector spinae). QLB does not target a nerve; it aims to target a fascial plane that is very bright, hyperechoic, and easily dissected. The current study was implemented by using QLB type two (posterior approach) as it is more safer than QLB type one (anterolateral) or the transmuscular approach QLB type three (in between QL and psoas muscles), as it has a more superficial point of injection, the needle tip is separated from the peritoneum by the QL muscle, so it avoids intraperitoneal injection and bowel injury, and it is associated with better US resolution ,.
In this study, levobupivacaine 0.25% was used with the lowest suggested volume of 0.5 ml/kg for both QLB and TAP block. Although Marjanovic et al.  have suggested that higher volumes of 0.6–1.0 ml/kg of levobupivacaine 0.25% caudally administered might be able to provide the same quality of intraoperative and postoperative analgesia in pediatric patients undergoing inguinal hernia repair and orchidopexy, some authors have reduced the applied volume to 0.5 ml/kg LA to avoid adverse effects and toxicity .
In a study by Frawley et al. , who compared (1 ml/kg) bupivacaine 0.25% versus (1 ml/kg) levobupivacaine 0.25% for caudal anesthesia for children, they noted that onset time, motor block, and analgesia of levobupivacaine were comparable with bupivacaine; however, levobupivacaine considerably reduced central nervous system and cardiovascular toxicity, allowing a larger dose to be given.
In this study, the intraoperative hemodynamic changes (MAP, HR) were comparable at baseline reading and immediately after induction. Then, they became statistically significantly lower in the QLB group 15 min after performing the block till the end of the surgery compared with TAP block group. This matched with Shafeek et al. , who compared QLB group, TAP block group, and control group for patients undergoing laparoscopic bariatric surgery and found that there was a statistically significant lower value of intraoperative HR and MAP in QLB group after 30 min of induction to after 120 min compared with other both groups. On the contrary, Baytar et al.  noticed no statistically significant difference between the QLB and TAP block groups in laparoscopic cholecystectomy regarding intraoperative HR and MAP; this may be explained as the authors used subcostal TAP block that was associated with higher dermatomal block rather than the classic TAP block which was used in this study.
The present study recorded statistically significant lower intraoperative fentanyl doses in children under QLB compared with TAP block group. This is in agreement with Yousef , who compared QLB versus TAP block in patients undergoing total abdominal hysterectomy and found that the total amount of intraoperative fentanyl consumption was significant higher in TAP block group than in QLB group. Moreover, Stuart Green et al.  revealed that intraoperative use of fentanyl was significant lower in patients receiving QLB for total hip arthroplasty compared with those not receiving QLB.
Regarding the VAS score, mean values were highly statistically significantly reduced in the first 4 h postoperatively for the QLB group compared with TAP block group; however, pain scores at the remaining time intervals were not statistically significantly different between both groups. Moreover, for the first time to rescue analgesics, this study showed significantly longer duration in children under QLB (P<0.001), and the total paracetamol given during the first postoperative 24 h was significant lower in QLB group (P<0.001).
Our results were in line with the results recorded by Yousef , who found that VAS score was significant higher in TAP block group than in QLB group at all the measured time postoperatively, duration of postoperative analgesia was shorter in TAP block group than in QLB group (8.33±4 vs. 15.1±2.12 h), and the mean amount of morphine used postoperatively was significant higher in TAP block group than in QLB group (14.46±3.4 vs. 10.06±3.8 mg, respectively). In a case series by Baidya et al.  involving five children undergoing pyeloplasty, transmuscular QLB block using 0.2% ropivacaine in a dose of 0.5 ml/kg gave very good postoperative pain control in comparison with TAP block. Another study by McCrum et al.  noticed that patients who had a preemptive QLB block for hip arthroscopy recorded lower VAS score and required significantly fewer postoperative opioids versus patients who did not receive a block.
In accordance with these results, a case report by Elsharkawy et al. , comparing anterior QLB with TAP block with liposomal bupivacaine, noted that using the same LA mixture, the duration of QLB was significant longer by four times than TAP block, and they explained that QLB does not result in lateral spread of LA but result in more spread to the thoracic paravertebral space. Moreover, QLB gives a wider range of sensory analgesia (T7–L1) in comparison with TAP block (T10–T12). In addition, a study by Chiao and Jung  using ropivacaine as a local anesthetic revealed that QLB has many benefits in comparison with TAP block, spread of the block between T7 and T12/L1 in comparison with small coverage by TAP block, and also duration of analgesia is 21 h compared with 7 h for TAP block. Another study by Öksüz et al.  showed that QLB in children undergoing unilateral inguinal hernia repair or orchiopexy provides effective and longer postoperative analgesia and lower face, legs, activity, cry, consolability (FLACC) score in comparison with TAP block.
These results were not compatible with Stuart Green et al. , who found that 24-h VAS pain scores and postoperative narcotic utilization were not statistically significant in patients receiving QLB for total hip arthroplasty compared with those not receiving QLB. They attributed this to the small sample size used (10 patients in each group). Moreover, lack of controlled timing of postoperative measurement of VAS may introduce bias as comforted patient at rest may report differently than those recently finishing physical therapy session, and also administering breakthrough medication at rest versus after physical therapy sessions may increase bias too.
It is surprising that several studies, such as a study by Tupper-Carey et al. , revealed that TAP block performed for skin incision in laparoscopic appendectomy did not significantly improve the outcomes of postoperative analgesia in adults. Moreover, a study by Sandeman et al.  showed that TAP block offered no extra benefit over local anesthesia infiltration in children undergoing laparoscopic appendectomy.
This study reported that the duration of hospital stay and postoperative nausea and vomiting were comparable between both groups, with no statistically significant difference.
This is in contrary to what Stuart Green et al. , cleared up that hospital stay was significantly shorter in patients receiving QLB (3 days) versus patients not receiving QLB (5 days); this may be explained by as our laparoscopic surgical procedure is associated with mild postoperative pain, whereas their total hip arthroplasty surgery is associated with moderate to severe pain and needs longer hospital stay for follow-up and physiotherapy. Moreover, their comparison group received no regional block. Another study by Shafeek et al.  noticed a statistically significant increase in postoperative nausea and vomiting in controlled group compared with QLB and TAP block groups, with no difference between the latter two groups.
When comparing parents’ and patients’ satisfaction between both groups, there was a statistically significant higher satisfaction in the QLB group. This matched with the results of Öksüz et al. , who documented that parent satisfaction scores were significantly higher in the QLB group compared with TAP block group. In addition, a case report by Murouchi  showed that bilateral QLB in a 7-year-old child undergoing laparoscopic appendectomy is a valuable technique in managing perioperative pain with good patient and parent satisfaction.
Some limitations of the present study are that the laparoscopic appendectomy is minimal invasive surgery that seems to be associated with less postoperative pain compared with laparotomy. Moreover, we did not test the sensory block plane level in those patients of the two groups, which may need further studies to evaluate it.
| Conclusion|| |
The results of this study concluded that QLB type 2 has to be taken into account as an effective technique for pain management in pediatric patients undergoing laparoscopic appendectomy, being associated with more intraoperative hemodynamic stability, longer postoperative analgesic time, and less rescue analgesics consumption compared with classic TAP block.
Financial support and sponsorship
Conflicts of interest
There are no conflcits of interest.
| References|| |
Li X, Zhang J, Sang L, Zhang W, Chu Z, Li X, Liu Y et al.
Laparoscopic versus conventional appendectomy—a meta-analysis of randomized controlled trials. BMC Gastroenterol 2010; 10:129.
Sabbagh C, Brehant O, Dupont H, Browet F, Pequignot A, Regimbeau JM et al.
The feasibility of short-stay laparoscopic appendectomy for acute appendicitis: a prospective cohort study. Surg Endosc 2012; 26:2630–2638.
Siddiqui MR, Sajid MS, Uncles DR, Cheek L, Baig MK. A meta-analysis on the clinical effectiveness of transverses abdominis plane block. J Clin Anesth 2011; 23:7–14.
McDonnell JG, O’Donnell BD, Tuite D, Farrell T, Power C. The regional abdominal field infiltration (R.A.F.I.) technique: computerized tomographic and anatomical identification of a novel approach to the transversus abdominis neurovascular fascial plane. Anesthesiology 2004; 01:A899.
Hebbard P, Fujiwara Y, Shibata Y, Royse C. Ultrasound guided transversus abdominis plane (TAP) block. Anaesth Intensive Care. 2007; 35:616–7.
Murouchi T. Quadratus lumborum block intramuscular approach for pediatric surgery. Acta Anaesthesiol Taiwan 2016; 54:135–136.
Kadam VR. Ultrasound-guided quadratus lumborum block as a postoperative analgesic technique for laparotomy. J Anaesthesiol Clin Pharmacol 2013; 29:550–552.
] [Full text]
Al-Sadek WM, Rizk SN, Selim MA. Ultrasound guided transversus abdominis plane block in pediatric patients undergoing laparoscopic surgery. Egypt J Anaesth 2014; 30:273–278.
Ueshima H, Otake H, Jui-An L. Ultrasound-guided quadratus lumborum block: an updated review of anatomy and techniques. Biomed Res Int 2017; 2017:1–7.
Carli F, Kehlet H, Baldini G, Steel A, McRae K, Slinger P et al.
Evidence basis for regional anesthesia in multidisciplinary fast-track surgical care pathways. Reg Anesth Pain Med 2011; 36:63–72.
Chakraborty A, Goswami J, Patro V. Ultrasound-guided continuous quadratus lumborum block for postoperative analgesia in a pediatric patient. A A Case Rep 2015; 4:34–36.
Blanco R, Ansari T, Riad W, Shetty N. Quadratus lumborum block versus transversus abdominis plane block for postoperative pain after cesarean delivery: a randomized controlled trial. Reg Anesth Pain Med 2016; 41:757–762.
Yousef NK. Quadratus lumborum block versus transversus abdominis plane block in patients undergoing total abdominal hysterectomy: a randomized prospective controlled trial. Anesth Essays Res 2018; 12:742–747.
Marjanovic V, Budic I, Stevic M, Simic D. A comparison of three different volumes of levobupivacaine for caudal block in children undergoing orchidopexy and inguinal hernia repair. Med Princ Pract 2017; 26:331–336.
Locatelli B, Ingelmo P, Sonzogni V, Zanella A, Gatti V, Spotti A et al.
Randomized, double-blind, phase III, controlled trial comparing levobupivacaine 0.25%, ropivacaine 0.25% and bupivacaine 0.25% by the caudal route in children. Br J Anaesth 2005; 94:366–371.
Frawley GP, Downie S, Huang GH. Levobupivacaine caudal anesthesia in children: a randomized double-blind comparison with bupivacaine. Paediatr Anaesth 2006; 16:754–760.
Shafeek AM, Gomaa GA, Abd ElMalek FA, Hassan KM, Muhammad DW. A comparative study between ultrasound guided quadratus lumborum block versus ultrasound guided transversus abdominis plane block in laporoscopic bariatric surgery. Egypt J Hosp Med 2018; 70:2190–2199.
Baytar C, Yılmaz C, Karasu D, Topal S. Comparison of ultrasound-guided subcostal transversus abdominis plane block and quadratus lumborum block in laparoscopic cholecystectomy: a prospective, randomized, controlled clinical study. Pain Res Manag 2019; 2019:2815301.
Stuart Green M, Ryan Hoffman C, Iqbal U, Olabisi Ives O, Hurd B. Transmuscular quadratus lumborum block reduces length of stay in patients receiving total hip arthroplasty. Anesth Pain Med 2018; 8:e80233.
Baidya DK, Maitra S, Arora MK, Agarwal A. Quadratus lumborum block: an effective method of perioperative analgesia in children undergoing pyeloplasty. J Clin Anesth 2015; 27:694–696.
McCrum CL, Ben-David B, Shin JJ, Wright VJ. Quadratus lumborum block provides improved immediate postoperative analgesia and decreased opioid use compared with a multimodal pain regimen following hip arthroscopy. J Hip Preserv Surg 2018; 5:233–239.
Elsharkawy H, Salmasi V, Soliman LM, Esa WAS, Blanco R. Anterior quadratus lumborum block versus transversus abdominis plane block with liposomal bupivacaine: a case report. J Anesth Crit Care Open Access 2016; 6:00214.
Chiao F, Jung B. Quadratus lumborum block: A more extensive spread and longer-lasting alternative to the transverses abdominus plane block? SPA News Clin Rev 2016; 29:3.
Öksüz G, Bilal B, Gürkan Y, Urfalioğlu A, Arslan M, Gişi G et al.
Quadratus lumborum block versus transversus abdominis plane block in children undergoing low abdominal surgery: a randomized controlled trial. Reg Anesth Pain Med 2017; 42:674–679.
Tupper-Carey DA, Fathil SM, Tan YK, Kan YM, Cheong CY, Siddiqui FJ, Assam PN et al.
A randomised controlled trial investigating the analgesic efficacy of transversus abdominis plane block for adult laparoscopic appendicectomy. Singapore Med J 2017; 58:481–487.
Sandeman DJ, Bennett M, Dilley AV, Perczuk A, Lim S, Kelly KJ. Ultrasound-guided transversus abdominis plane blocks for laparoscopic appendicectomy in children: a prospective randomized trial. Br J Anaesth 2011; 106:882–886.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2]