ORIGINAL ARTICLE
Year : 2022 | Volume
: 10 | Issue : 1 | Page : 6--13
Efficacy of ultrasound guided quadratus lumborum plane-1 block for post operative analgesia at iliac / hypogastric donor sites in patients undergoing reconstructive surgery with graft harvest from dermatomal area t7 - l1 : A prospective randomised controlled study
A Muralikrishna Srivatsav1, V Boopathi1, Divya Sankuru2, Shibu Sasidharan3, Babitha Manalikuzhiyil4, Harpreet Singh Dhillon5,
1 Department of Anaesthesia, Ganga Medical Centre and Hospital, Coimbatore, Tamil Nadu, India
2 Department of Pediatrics, Apollo Medical College and General Hospital, Hyderabad, Telangana, India, India
3 Department of Anaesthesia and Critical Care, Command Hospital, Chandimandir, Panchkula, Haryana, India
4 Department of Radiodiagnosis and Imaging, Ojas Hospital, Chandimandir, Panchkula, Haryana, India
5 Department of Psychiatry, Command Hospital, Chandimandir, Panchkula, Haryana, India
Correspondence Address:
Dr. Shibu Sasidharan
Departments of Anaesthesia and Critical Care and Psychiatry, Level III UN Hospital, Goma
India
Abstract
Background: Ultrasound-guided quadratus lumborum plane-1 (QLP-1) block involves placement of local anesthetic lateral to the quadratus lumborum muscle. It provides better and long-lasting analgesia than transverse abdominis plane block due to the spread of local anesthetic more posteriorly along the thoracolumbar fascial plane, thus involving the L1 dermatomal area.
Objectives: We conducted a study to evaluate the efficacy of ultrasound-guided QLP-1 block for postoperative analgesia at iliac/hypogastric donor sites in patients undergoing reconstructive surgery with graft harvest from dermatomal area T7-L1.
Materials and Methods: After obtaining approval from the ethical committee, a randomized controlled trial was conducted from February 2018 to November 2018. Eighty patients were randomly allocated into two equal groups, Group A (QLP-1 block) and Group B (control, without any block, and only iv analgesics) based on computer-generated random number techniques. Twenty ml of local anesthetic mixture containing 0.5% bupivacaine and 2% lignocaine with adrenaline and 4 mg of dexamethasone was for QLP-1 block in Group A. Aim was to assess pain scores every second hourly up to 24 h and secondary objective was the requirement of rescue analgesia. SPSS version 19 was used to derive statistical results. The unpaired t-test is used for quantitative analysis.
Results: The numerical pain score (NPS) was significantly low in Group A compared to Group B between 6th and 12th h after the block (P < 0.001). The mean time at which first rescue analgesia had to be given was significantly later in group A (15.55 h) compared to Group B (6.25 h). The requirement of double rescue analgesia in the first 24 h after the block was higher in Group B (100%) compared to Group A (0%).
Conclusion: Ultrasound-guided QLP-1 block is safe, hemodynamically stable, and provided superior analgesia at iliac/hypogastric donor sites compared to control group in patients undergoing reconstructive surgery with graft harvest from dermatomal area T7-L1. The number of rescue analgesics required in the QLP-1 group is less compared to the control group.
How to cite this article:
Srivatsav A M, Boopathi V, Sankuru D, Sasidharan S, Manalikuzhiyil B, Dhillon HS. Efficacy of ultrasound guided quadratus lumborum plane-1 block for post operative analgesia at iliac / hypogastric donor sites in patients undergoing reconstructive surgery with graft harvest from dermatomal area t7 - l1 : A prospective randomised controlled study.MRIMS J Health Sci 2022;10:6-13
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How to cite this URL:
Srivatsav A M, Boopathi V, Sankuru D, Sasidharan S, Manalikuzhiyil B, Dhillon HS. Efficacy of ultrasound guided quadratus lumborum plane-1 block for post operative analgesia at iliac / hypogastric donor sites in patients undergoing reconstructive surgery with graft harvest from dermatomal area t7 - l1 : A prospective randomised controlled study. MRIMS J Health Sci [serial online] 2022 [cited 2023 Oct 3 ];10:6-13
Available from: http://www.mrimsjournal.com/text.asp?2022/10/1/6/337525 |
Full Text
Introduction
Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage.[1]
Posttraumatic skin, soft tissue, and bony defects of the upper limb represent a challenging problem to restore function and esthetic appearance. Autogenous grafts are considered the method of choice as there is no tissue incompatibility, no disease transfer, and no allergic reactions.[2] The iliac crest is most commonly used because of its ease of access to large quantities of both cancellous and cortical bone.[3]
Immediate postoperative pain at the donor area is more distressing to the patient as uncontrolled postoperative pain may increase the incidence of postoperative complications.[4] Untreated pain in the immediate postoperative period can lead to patient stress, slow recovery, and the development of chronic pain in later life.[5] Acute pain results in hemodynamic changes, such as hypertension, tachycardia, and increased tissue oxygen demand, which can cause myocardial ischemia.[6] Acute pain can decrease ventilation and predispose the patient to pulmonary complications. Severe acute pain causes metabolic and hormonal changes that inhibit fibrinolysis.[6] This inhibition of fibrinolysis may increase thrombotic complications, such as deep venous thrombosis and pulmonary embolism, which are the leading causes of morbidity after elective reconstructive orthopedic surgery.[6] Furthermore, it can lead to complications like delirium, depression, and sleep disturbances.[7],[8]
The main aim of postoperative pain management is to alleviate pain to a tolerable limit with minimal or no associated distress.[9] To accomplish these goals, different methods have been proposed. The various modalities available for postoperative pain control are the use of medications such as opioids and nonopioid drugs (paracetamol, Nonsteroidal anti-inflammatory drugs (NSAID's), alpha 2 agonists, tricyclic antidepressants, and Gabapentinoids),[10] Central neuraxial techniques like epidural analgesia and regional techniques like thoracic paravertebral block, Transverse abdominal plane block, and quadratus lumborum plane (QLP) blocks.[11],[12]
Epidural analgesia is associated with shorter postoperative ileus, hypotension, postoperative urinary retention, and delayed ambulation of patients.[13-16] Bupivacaine has long-lasting sensory blockade, and accidental intravascular injection of bupivacaine may be cardiotoxic.[17]
Dexamethasone's properties include anti-inflammatory response, immunosuppression, anti-emesis, and analgesia.[17],[18] Ultrasound guidance helps the practitioner monitor correct needle placement, the spread of local anesthetics, and reduce the dose of local anesthetics compared to blind technique.[19],[20]
Thoracic paravertebral block has been used as an alternative to epidural analgesia. Both blind and ultrasound-guided techniques are available with varying success and complication rates.[21] As the local anesthetic is deposited close to segmental spinal nerves at the point of exit from the intervertebral foramina, may cause unilateral sympathetic blockade and hemodynamic disturbances.[22] Furthermore, it necessitates individual blockade of T12 and L1 nerve roots because of the unpredictable cephalocaudal spread of local anesthetics. In addition, superior costotransverse ligament and pleura, which are key ultrasound landmarks, are not present at T12 and L1 levels, making real-time ultrasound guidance technically challenging.[23]
Standard ultrasound-guided transverse abdominis plane blocks are widely used for surgeries involving the inferior part of the umbilical wall.[24] It involves the placement of local anesthetics in the plane between the inferior oblique and transverse abdominis muscles. However, it provides inferior analgesia and patchy block because of the sparing of L1 dermatome.[25]
Ultrasound-guided QLP-1 block involves placement of local anesthetic lateral to the quadratus lumborum muscle.[26-28] It provides better and long-lasting analgesia than transverse abdominis plane block due to the spread of local anesthetic more posteriorly along the thoracolumbar fascial plane, thus involving the L1 dermatomal area.[12],[29]
Hence, in this study, we demonstrate the efficacy of ultrasound-guided QLP block-1 for postoperative analgesia at iliac/hypogastric donor sites in patients undergoing reconstructive surgery with graft harvest from T7-L1 dermatomal area using a 10-point numeric pain score assessment scale.
Materials and Methods
Prospective randomized controlled trial, done at a tertiary level trauma hospital in South India over 1 year (2018–19). Eighty patients were recruited. (Forty in each group) (based on the article titled the analgesic effect of ultrasound-guided quadratus lumborum block after cesarean delivery: A randomized clinical trial and the proportion used to measure the parameter requirement of rescue analgesia is 4% with an alpha of 5%, the corresponding z value is -1.95996398454005. Using the above formula with the minimum percentage difference to be deemed clinically significant as 6.1%, the sample size required would be 40 in each group for the study).
Inclusion criteria
Patients of either sex between 16 and 60 yearsAmerican Society of Anesthesiologists (ASA I) and ASA II physical statusPatients undergoing pedicled groin and abdominal flap cover for posttraumatic upper limb, skin, and soft-tissue reconstructionsPatients undergoing iliac crest bone harvesting for orthopedic surgeries of the upper limb.
Exclusion criteria
Patients <16 years, >60 years of agePatients of ASA III and above physical statusPatients with bleeding diathesisPatients on anti-coagulants and anti-platelet drugsPatients allergic to local anesthetic drugsPatients with localized sepsis at the site of injection.
Methodology
After thoroughly explaining the patients and attenders regarding the nature of the study and after obtaining informed consent, patients will be allocated to either of the study or the control group using a computer-generated randomization system.
Group A (n = 40): USG guided QLP-1 blockGroup B (n = 40): Control group (no block, and only analgesics iv).
Procedure
Institutional ethical clearance was taken. Informed consent was taken. Patients are then explained by the use of a 10 point numeric pain score assessment scale [Figure 1] graded from 0 (no pain) to 10 (worst pain). Each patient was monitored in the postanesthesia care unit from the time of completion of surgery to 24 h postblock.{Figure 1}
On arrival to the operation theater, all standard noninvasive monitors are attached, baseline vital parameters are recorded. IV access secured with 20G cannula and crystalloid infusion with ringer's lactate or normal saline started.
Technique
With the patient in a supine position, A linear or curvilinear ultrasound probe is oriented transversely over the lateral abdomen between the iliac crest and the costal margin [Figure 2]. The external oblique, internal oblique, and transversus abdominis muscles are imaged and the more posterior transversus aponeurosis is distinguished.{Figure 2}
The reflection of the peritoneum curving away from the muscles from anterior to posterior is identified, and the perinephric fat, which lies behind the peritoneum and deep to the transversalis fascia, identified. The perinephric fat is generally more prominent closer to the iliac crest. The quadratus lumborum is identified medial to the aponeurosis of the transversus abdominis [Figure 3].{Figure 3}
Patients are then given an ultrasound-guided brachial plexus block by subclavian perivascular approach on the affected side with 20 milliliters of the local anesthetic mixture and dexamethasone 4 mg under repeated aspiration for each fifth milliliter injected.
Then, the patient is made to sit and subarachnoid block given with 0.5% hyperbaric bupivacaine in L3–L4 interspace for surgical anesthesia. The patients in the study group are then given a QLP-1 block. The patient is then made supine, and the side to be blocked is slightly elevated with pillows under the hips and shoulders. A sterile draped high-frequency linear probe is placed in the transverse plane on the flank of the patient's cranial to the iliac crest and at the level of the umbilicus. The anterior abdominal muscle layers are identified, the transducer is then moved posteriorly to visualize the aponeurosis of the transverse abdominis muscle. The pararenal fat and quadratus lumborum muscle were imaged medial to the aponeurosis. A sterile 23G Quincke needle is then advanced out of the plane under ultrasound guidance through the muscle layers of the abdominal wall. The needle tip was advanced to the transverse aponeurosis and positioned superficial to the pararenal fat and lateral to the border of the quadratus lumborum muscle. Five millimeters of normal saline is injected to verify the correct position of the needle and if necessary, the needle may be repositioned. After confirming the needle placement, 20 mm of the local anesthetic mixture and dexamethasone 4 mg injected under repeated aspiration for every 5th ml injected.
After the completion of the surgery, patients are shifted to postanesthesia care unit (PACU) for observation of any complications and adverse effects. All patients in Group B were given intravenous paracetamol 15 mg/kg 6th hourly for 24 h after surgery. Vital parameters and numeric pain rating score on a 10 point scale is noted immediately on shifting to PACU and every second hourly to 24 h after surgery in both study and control groups. Need for rescue analgesia is noted and times for administration of rescue analgesia from the time of block are noted in the first 24 h after surgery in both groups.
Rescue analgesics are given if the patient has numeric pain score of 3 or more at rest. Intravenous ketorolac 0.5 mg/kg body weight was considered as the first choice rescue analgesia and intravenous tramadol 1 mg/kg body weight diluted in 100 ml of normal saline is given as second choice rescue analgesia.
Results
The study was conducted for a period of 1 year spanning 2018–19. There were no exclusions or fall-outs from the study group. [Table 1]a shows the demographic pattern of the patients.{Table 1}
Statistical methods
Descriptive and inferential statistical analysis has been carried out in the present study. Results for continuous measurements are presented on mean ± standard deviation (min-max) and results for categorical measurements are presented by number (%). Significance is assessed at a 5% level of significance.
Student t-test (two-tailed, independent) has been used to find the significance of study parameters on a continuous scale between two groups (intergroup analysis) on metric parameters.
Chi-square/Fisher Exact test has been used to find the significance of study parameters on a categorical scale between two or more groups.
Significant figures (P < 0.05)Type I error of 5%Power of the study, 80%.
Statistical software
The Statistical Package for the Social Sciences (SPSS) Version 19 was used for the analysis of the data. Microsoft Word 2016 and Excel 2016 have been used to generate graphs, tables, etc.
[Graph 1] shows that there is not much variability in the trend of heart rate (HR) between the two groups for a period of 24 h. According to the repeated analysis of variance (ANOVA) test P > 0.05, which is statistically insignificant.[INLINE:1]
The above [Table 1] shows the trend of NPS over a period of 24 h at every 2 h interval after the block in both groups. By unpaired student t-test, the P < 0.05 from 6 h till 12 h after the block stating that Group A (QLP-1 block) had better analgesia in postoperative period when compared to Group B (control group) from 6 h till 12 h after the block. After 12 h, P value is consistent >0.05 which is statistically insignificant.
[Table 2] and graph show the requirement of the requirement of rescue analgesia at every 2nd hourly interval until 24 h after the block in both Group A (QLP-1 block) and Group B (control group). This shows that the requirement of rescue analgesia is more in Group B when compared to Group A.{Table 2}
[Table 3] and graph show that the meantime of requirement of first rescue analgesia in Group B (control group) is 6.25 h when compared to 15.55 h for Group A (QLP-1 block). This shows that there has been a statistically significant difference in the mean time for the requirement of first rescue analgesia between Group A and Group B with a P < 0.001.{Table 3}
[Table 4] shows that patients in Group B (Control group) required more number of rescue analgesics and all patients required double rescue analgesia in the first 24 h. This shows that patients in Group A (QLP-1 block) required less rescue analgesia and no need for double rescue analgesia with a significant P < 0.001.{Table 4}
Discussion
The most common modalities used for reconstructive surgery of upper limb defects are pedicled groin and abdominal flap covers and iliac crest bone harvest especially in orthopedic trauma spine arthrodesis and maxillofacial surgery like alveolar bone grafting. Iliac crest is most commonly used because of its ease of access to large quantities of both cancellous and cortical bone. Autogenous grafts are considered method of choice as there is no tissue incompatibility, no disease transfer, and no allergic reactions.
Pain at the harvesting site is more distressing in the postoperative period, especially in the first 24 h. Uncontrolled and poorly managed postoperative pain produces both acute and chronic detrimental effects in the postoperative period. Persistent untreated pain also leads to negative neuroplasticity and discomfort to the patient. Therefore it becomes necessary to provide excellent and high-quality pain relief in the postoperative period with minimum side effects and improved patient satisfaction.
Among the various treatment modalities, regional anesthesia techniques provide excellent pain relief and lesser side effects. In our study, 80 patients undergoing reconstructive surgery of the upper limb were grouped into two groups of 40 each. All patients were comparable with respect to the demographic parameters: Age, sex. All patients were comparable with respect to the ASA physical status. All the patients were clinically and statistically comparable with respect to hemodynamic parameters: HR, systolic blood pressure, diastolic blood pressure. Basal preblock NPS was the same (0) in both groups as the block is performed before surgical incision after subarachnoid block. Ultrasound guided QLP-1 block was performed in Group A by experienced anesthesiologist. Good quality ultrasound image of QLP-1 was acquired and the spread of local anesthetic was visualized. We used 20 ml of a local anesthetic mixture containing 0.5% bupivacaine, 2% lignocaine with adrenaline, and dexamethasone 4 mg. We preferred to use local anesthetic mixture to decrease the requirement of bupivacaine and adrenaline acts as a marker for early detection of inadvertent intravascular injections.
In our study, we evaluated the analgesic efficacy of QLP-1 block with respect to numeric pain score (NPS) and the requirement of rescue analgesics over the first 24 hours in the postoperative period.
Krohg et al.,[29] in 2013 did a randomized clinical trial to determine cumulative Ketobemidone consumption in 24 h after Cesarean delivery in 40 patients of which 20 patients undergone ultrasound-guided QLP-1 block. Hence, in our study, we choose 80 patients as our study sample with 40 patients in each group to obtain clinical significance of 5% and power of 80%.
In the current modern period of anaesthesia, ultrasound-guided block have become the ―gold standard in peripheral neural blockade which enables a reduction in local anesthetic dose. According to the review article published by Vermeylen et al.,[30] the precise and real-time visualization of the injected local anesthetics spread under ultrasound-guided block may represent the best requisite for reducing local anesthetics dose and local anesthesia related side effects.
The use of adjuvants in peripheral nerve blocks is well advocated. A plain peripheral block with longer-acting local anesthetics provides effective analgesia up to 6–8 h. Rasmussen et al.,[31] in their study found that the addition of dexamethasone provided longer and effective pain relief than the local anesthetic alone. Khurana et al.,[32]in their study found that the addition of dexamethasone in the brachial plexus block provided faster onset and longer duration of pain relief which was desired in our patients. Hence, 4 mg of dexamethasone was used as adjuvant of choice in our study.
The hemodynamic parameters were compared using the ANOVA test, the results are statistically insignificant with P > 0.05.
The primary objective of this study, the quality of analgesia using NPS over 24 h at 2 h interval is compared using the unpaired student t-test. The results showed that Group A (QLP-1) had a better quality of analgesia compared to Group B (Control) with a significant P < 0.001 between 6th h and 12th h after the block. There was no significant difference in the first 6 h between both groups because of the subarachnoid block given for surgical anesthesia. The results are compared to Krohg et al.,[29] where the effective analgesic scores are less in patients undergoing QLP block compared to the placebo group, both at rest and during coughing in the first 24 h after surgery with a P < 0.01.
The secondary objectives of this study, the percentage of patients requiring rescue analgesia in the form of NSAID (Ketorolac) and opioid (Tramadol) were compared between both the groups. Though the difference in the number of patients requiring first rescue analgesia in the form of Ketorolac was not statistically significant between both groups, the mean time at which first rescue analgesia was required in Group A (QLP-1 block) was 15.55 h when compared to 6.25 h in Group B (Control).
The percentage of patients requiring second rescue analgesia in the form of tramadol is 0% in Group A compared to 100% in Group B. The percentage of patients requiring double rescue analgesia was 100% in Group B (control) compared to 0% in Group A (QLP-1 block).
The total number of rescue analgesics required for patients over 24 h is more in Group B (80) compared to Group A (40). The results were compared to Krohg et al. study where the effective analgesic score both at rest and during coughing and cumulative ketobemidone consumption in 24 h were reduced in the treatment group (QLPB group) compared to the placebo group with a significant P < 0.01.
Limitations
There was no statistically significant difference in NPS between 12 and 24 h after the blockThe time of onset of analgesia after the block in Group A couldn't be assessed as the block is performed after subarachnoid block for surgical anesthesiaThe effects of systemic absorption of dexamethasone were not monitored in our studyAnother limitation is that our study was carried out in one center. A multicentric study with a larger sample size can highlight the effectiveness of QLP-1 block in postoperative analgesia.
Conclusion
Ultrasound-guided QLP-1 block is safe, hemodynamically stable, and easy to performUltrasound-guided QLP-1 block is effective in providing postoperative analgesia at iliac/hypogastric sites until 12 h in patients undergoing reconstructive surgeryQLP-1 block helps in avoiding opioid usage in the first 24 h following surgeryQLP-1 block helps in achieving a larger duration of postoperative analgesia after wearing off Sub-arachnoid blockUse of rescue analgesia was not required until 16 h (15.55 h) in Group AQLP-1 block helped in avoiding the second rescue analgesia.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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