Anatomical bases for paravertebral anesthetic block: fluid communication between the thoracic and lumbar paravertebral regions

Proof of concept study of the posterior quadratus lumborum block for laparoscopic myomectomy: A randomized controlled trial

In the United States, 65,000 myomectomies are performed annually to treat uterine fibroids. The quadratus lumborum block (QLB) is an effective block for laparoscopic pelvic surgery, urologic surgery, hip surgery and cesarean sections, with limited data for laparoscopic myomectomies. We evaluated the posterior QLB in reducing MME consumption and numeric rating scale (NRS) pain scores in patients undergoing laparoscopic myomectomies. Twenty-two subjects were enrolled in this single-center, randomized, controlled study between March 28, 2019 and June 16, 2020 and were randomized to either the QLB or control group. Seven subjects were excluded from the final analysis, 5 after being lost to follow-op and 2 for not meeting the inclusion criteria. Recipients in the QLB group received bilateral posterior QLBs, with 30 mL of 0.25% ropivacaine per injection. The primary outcome of MME use at 24 hours was not significant between the QLB group and the control group (23.3 ± 8.5 mg vs. 25.7 ± 14.4 mg, p = 0.859). The secondary outcome of NRS pain scores was also not significant between groups (p > 0.05). While this study did not provide evidence that QLB may be useful in reducing opioid consumption or pain scores in patients undergoing laparoscopic myomectomies, further studies with a larger sample size will be valuable to determine the effectiveness of this block for laparoscopic myomectomy.

Comparison of two approaches to quadratus lumborum block for postoperative analgesia in radical cystectomy: a randomized clinical trial

BACKGROUND

The aim of this study was to evaluate the analgesic effects following radical cystectomy using two ultrasound guided quadratus lumborum block (QLB) techniques: anterior and intramuscular.

METHODS

Sixty patients aged 40-60 years old with ASA I, II were considered for this study. They were divided into two equal groups. Bilateral ultrasound guided QLB was performed via either the anterior (QLBa) or intramuscular (QLBi) approach with 2.5 mg/kg of 0.25% bupivacaine diluted to 20 mL of normal saline after surgery. The primary outcome was the time to the first request for analgesia, while the secondary outcomes were the dose of postoperative morphine consumption, numerical rating scale (NRS) at rest and on movement, Bromage Scale, adverse events, and patient satisfaction.

RESULTS

The mean time to first request for analgesia was significantly prolonged in group QLBa (14.7±1.33 hours) compared to group QLBi (9.8±0.72 hours) (P<0.001). NRS either at rest or on movement were not statistically significant until six hours postoperatively. At 10, 12, and 14 h, Group QLBi had a significantly higher NRS Score at rest and on movement (P<0.001). Group QLBa had a significantly lower total morphine consumption (5.37±0.49 mg) compared to Group QLBi (6.4±0.77 mg) (P<0.001). The QLBa had higher patient satisfaction than the QLBi.

CONCLUSIONS

Compared with QLBi, bilateral ultrasound guided QLBa provided a longer time to the first analgesic request, less postoperative opioid consumption, lower NRS at rest and on movement, and higher patients' satisfaction after radical cystectomy under general anesthesia.

[Old and New Regional Anesthesia Procedures Under Review - Abdomen to Toe]

Ultrasound (US) technology has significantly expanded the spectrum of regional anesthesiological procedures in recent years. Abdominal wall blocks are becoming an increasingly integral part of a multimodal postoperative pain concept after abdominal surgery, gynecological or urological interventions. Thoracic epidural analgesia remains the gold standard for extensive surgery. The requirement for rapid postoperative mobilization and discharge after lower extremity surgery has led to the abandonment of neuroaxial or plexus blocks in favor of selective, peripheral blocks such as the PENG block or adductor canal block. The following article is intended to show the reader the change in the use of regional anesthesiological procedures for abdominal wall and lower extremity blocks using selected blockages.

Comparison of ultrasound-guided transversalis fascia plane block and anterior quadratus lumborum block in patients undergoing caesarean delivery: a randomized study

BACKGROUND

Cesarean section is becoming increasingly common. Well-managed postoperative analgesia improves patient comfort while encouraging early ambulation and breastfeeding. The analgesic efficacy of transversalis facial plane block (TFPB) vs. anterior quadratus lumborum block (QLB) was compared in this study.

METHODS

We analyzed the data of 49 pregnant women (gestation, ≥ 37weeks; age, 18-45years) scheduled for elective cesarean delivery (CD) under general anesthesia. They were randomly divided into TFPB and anterior QLB groups. All blocks were administered bilaterally with 25mL of 0.25% bupivacaine under ultrasound guidance prior to extubation. Postoperative morphine consumption and numerical rating scale (NRS) pain scores (static and dynamic [during coughing]) were recorded at 1, 3, 6, 9, 12, 18, and 24h.

RESULTS

There was no difference in postoperative morphine consumption between the groups at the third, sixth, and ninth hours, but the anterior QLB group consumed less morphine at the 12th, 18th, and 24th hours. Except for the first hour, resting and dynamic NRS scores were comparable between the groups. The first-hour resting and dynamic NRS scores were lower in the TFPB group (resting NRS, anterior QLB group, median [interquartile range], 2 [2-3] vs. TFPB group, 2 [0-2], p = 0.046; dynamic NRS, anterior QLB group, median [interquartile range], 3 [2-4] vs. TFPB group 2 [0-3], p = 0.001).

CONCLUSIONS

In patients undergoing CD, anterior QLB decreased morphine consumption in the late period (9-24h) compared to TFPB, while pain scores were similar between both groups. The reduction in morphine consumption was statistically significant, but not clinically significant.

Effect of Quadratus Lumborum Block on Pain and Stress Response after Video Laparoscopic Surgeries: A Randomized Clinical Trial

BACKGROUND

There are many surgical and anesthetic factors that affect pain and the endocrine-metabolic response to trauma. The ability of anesthetic agents and neuronal blockade to modify the response to surgical trauma has been widely studied in the last few years.

OBJECTIVE

To evaluate if the anterior quadratus lumborum block contributes to improved surgical recovery, using as parameters analgesia, pulmonary function and neuroendocrine response to trauma.

METHODS

We carried out a prospective, randomized, controlled, and blinded study, in which 51 patients scheduled for laparoscopic cholecystectomy. Patients were randomly selected and assigned to 2 groups. The control group received balanced general anesthesia and venous analgesia, and the intervention group was treated under general, venous analgesia and anterior quadratus lumborum block. The parameters evaluated were: demographic data, postoperative pain, respiratory muscle pressure and inflammatory response to surgical stress with the plasma dosage of IL-6 (Interleukin 6), CRP (C-Reactive protein) and cortisol.

RESULTS

Anterior quadratus lumborum block induced the slowing of IL-6 cytokine production and a decrease in cortisol release. This effect was accompanied by the significant reduction of postoperative pain scores.

CONCLUSION

Anterior quadratus lumborum block is an important strategy for analgesia in abdominal laparoscopic surgery and contributes to reducing the inflammatory response to surgical trauma with an early return of preoperative baseline physiological functions.

Postoperative Pain Management in Children Undergoing Laparoscopic Appendectomy: A Scoping Review

Laparoscopic appendectomy (LA) is one of the most commonly performed surgical procedures in children and is associated with extreme postoperative discomfort due to peritoneal inflammation and infection. The main objective of this study was to investigate the effects of postoperative pain (POP) in children after laparoscopic appendectomy. Articles describing or evaluating the control of POP in children with LA were considered eligible. All available literature such as randomized controls, prospective controls, retrospective as well as clinical studies were considered. A comprehensive search was performed in PubMed, Medline, Embase, Cochrane Library, Clinical trials.gov, and Google scholar. The initial search took place on 23 April 2021, and was updated on 24 August 2021. There were no language or date restrictions. Each of the included articles was evaluated separately by two independent reviewers. Additional papers were found by searching the reference lists of eligible studies. Eighteen papers were considered. All papers, and many of them used different methods to treat POP in children undergoing LA, such as lidocaine infusion, different analgesic approaches, ultrasound-guided transverse abdominis blockade (UGTAP), ultrasound-guided quadratus lumborum blockade (UGQLB), and comparison of open appendectomy (OA) with local anesthetics in relation to POP management in children. Laparoscopic appendectomy is the surgical procedure preferred by clinicians compared with open appendectomy in children. A multimodal analgesic approach is optimal and efficient surgical techniques such as UGBRSB, UGQLB, and UGTAP block might significantly impact POP in children except that there are contraindications. Dexmedetomidine proved to be an effective adjuvant that can enhance the effect of local anesthetics. The lack of a sufficient number of studies may be a factor affecting our confidence in the results of this study. Therefore, further evidence-based randomized control trials with a large sample size are needed to provide clarity.

Advantages of Transmuscular Quadratus Lumborum Block via Subfascial Approach Versus Extrafascial Approach for Postoperative Analgesia After Laparoscopic Cholecystectomy: A Randomized Controlled Study

OBJECTIVE

We aimed to compare the analgesic effect and incidence of lower limb weakness of transmuscular quadratus lumborum (TQL) block via subfascial approach with that via extrafascial after laparoscopic cholecystectomy (LC).

METHODS

Eighty patients undergoing LC were randomized to receive ultrasound-guided bilateral TQL block via subfascial (subfascial group) or extrafascial (extrafascial group) using 30 mL of 0.33% ropivacaine unilaterally. Pain scores of port sites while rest and coughing at 1, 6, 12, 24, 36, and 48 hours postoperatively as primary outcome were compared. Modified Lovett Rating Scale, ambulatory dependency, and rescue analgesia requirement was also compared.

RESULTS

The pain score of the subxiphoid and of the right subcostal port site for up to the postoperative 36 hours (2 [1 to 2]) and 24 hours (2 [2 to 3]) in the subfascial group was significantly lower than that in extrafascial group (2 [2 to 2] and 3 [2.25 to 4]). Up to postoperative 24 hours, the rescue analgesia requirement in subfascial group was significantly lower than that in extrafascial group, namely less fentanyl consumption and parecoxib (1.3 [±5.5] μg vs. 5.6 [±10.6] μg; 17.5% vs. 37.5%). The ratio of patients with LRS score of 6 at postoperative 1 hour (65.0%), and with dependent ambulation at postoperative 1 and 6 hours in subfascial group (15.0% and 0.0%) was significantly lower than that in extrafascial group (10.0%, 80.0%, and 17.5%).

CONCLUSION

TQL block via subfascial had the advantages of better analgesic effect and less lower limbs weakness after LC over that via extrafascial.

Understanding fascial anatomy and interfascial communication: implications in regional anesthesia

With the extensive application of ultrasound in regional anesthesia, there has been rapid development of interfascial plane block techniques recently. Compared with neuraxial anesthesia or nerve plexus blocks, the interfascial plane blocks have many advantages, such as technical simplicity, fewer complications and comparable or better analgesia. The concept of fascial interconnectivity is fundamental in understanding the effects and complications of interfascial plane blocks. Many fascial planes are continuous and communicate with each other without a clear anatomical boundary. The prevertebral fascia of the neck, endothoracic fascia of the chest, transversalis fascia of the abdomen, and the fascia iliaca of the pelvic cavity form a natural fascial continuation. This anatomical feature suggests that the space beneath the cervical prevertebral fascia, the thoracic paravertebral space, the space between transversalis fascia and psoas muscles (psoas major and quadratus lumborum), and the fascia iliaca compartment are a confluent potential cavity. Additionally, the permeability of the fascia at different anatomical locations to local anesthetics is different, which can also influence the block effect and the incidence of complications. This article summarizes the anatomical characteristics and communication relationships of the major fascia which are related to regional anesthesia, and their relationships with block effects and complications.

Anatomical classification and clinical application of thoracic paraspinal blocks

Various techniques for regional anesthesia and analgesia of the thorax are currently being used in clinical practice. A recent international consensus has anatomically classified paraspinal blocks in the thoracic spinal region into the following four types: paravertebral, retrolaminar, erector spinae plane, and intertransverse process blocks. These blocks have different anatomical targets; thus, the spreading patterns of the injectates differ and can consequently exhibit different neural blockade characteristics. The paravertebral block directly targets the paravertebral space just outside the neuraxial region and has an analgesic efficacy comparable to that of the epidural block; however, there are multiple potential risks associated with this technique. Retrolaminar and erector spinae plane blocks target the erector spinae plane on the vertebral lamina and transverse process, respectively. In anatomical studies, these two blocks showed different injectate spreading patterns to the back muscles and the fascial plane. In cadaveric studies, paravertebral spread was identified, but variable. However, numerous clinical reports have shown paravertebral spread with erector spinae plane blocks. Both techniques have been found to reduce postoperative pain compared to controls; however, the results have been more inconsistent than with the paravertebral block. Finally, the intertransverse process block targets the tissue complex posterior to the superior costotransverse ligament. Anatomical studies have revealed that this block has pathways that are more direct and closer to the paravertebral space than the retrolaminar and erector spinae plane blocks. Cadaveric evaluations have consistently shown promising results; however, further clinical studies using this technique are needed to confirm these anatomical findings.

Anatomical method for rib disconnection during posterior costotransversectomy for paravertebral access to the ventral thoracic spine

Posterior surgical approaches to the thoracic spine are commonly used for degenerative diseases, tumors, trauma, and other operative indications. A posterior approach for access to the paravertebral space is advantageous because it allows for resection of the vertebral body without violating the pleural cavity. Posterior costotransversectomy (PCT) is widely used for this purpose. It involves resection of the rib head after the ligamentous complexes have been disconnected from the transverse process and lateral vertebral body. The current literature provides only vague descriptions of the steps involved in rib disconnection with respect to PCT. A comprehensive knowledge of the anatomical relationships of the ligamentous and soft tissue complexes connecting the rib to the vertebral body is paramount for completing an efficient and safe surgery. This manuscript describes an anatomically directed method for rib disconnection during costotransvrersectomy.

Anatomical basis of fascial plane blocks

Fascial plane blocks (FPBs) are regional anesthesia techniques in which the space ("plane") between two discrete fascial layers is the target of needle insertion and injection. Analgesia is primarily achieved by local anesthetic spread to nerves traveling within this plane and adjacent tissues. This narrative review discusses key fundamental anatomical concepts relevant to FPBs, with a focus on blocks of the torso. Fascia, in this context, refers to any sheet of connective tissue that encloses or separates muscles and internal organs. The basic composition of fascia is a latticework of collagen fibers filled with a hydrated glycosaminoglycan matrix and infiltrated by adipocytes and fibroblasts; fluid can cross this by diffusion but not bulk flow. The plane between fascial layers is filled with a similar fat-glycosaminoglycan matric and provides gliding and cushioning between structures, as well as a pathway for nerves and vessels. The planes between the various muscle layers of the thorax, abdomen, and paraspinal area close to the thoracic paravertebral space and vertebral canal, are popular targets for ultrasound-guided local anesthetic injection. The pertinent musculofascial anatomy of these regions, together with the nerves involved in somatic and visceral innervation, are summarized. This knowledge will aid not only sonographic identification of landmarks and block performance, but also understanding of the potential pathways and barriers for spread of local anesthetic. It is also critical as the basis for further exploration and refinement of FPBs, with an emphasis on improving their clinical utility, efficacy, and safety.

Anterior quadratus lumborum block for ambulatory laparoscopic cholecystectomy: a randomized controlled trial

AIM

To explore the effects of an anterior quadratus lumborum block (QLB) on opioid consumption, pain, nausea, and vomiting (PONV) after ambulatory laparoscopic cholecystectomy.

METHODS

This randomized controlled study recruited 70 patients scheduled for ambulatory laparoscopic cholecystectomy from January 2018 to March 2019. The participants were randomly allocated to one of the following groups: 1) anterior QLB (n=25) with preoperative ropivacaine 3.75 mg/mL, 20 mL bilaterally; 2) placebo QLB (n=22) with preoperative isotonic saline, 20 mL bilaterally; and 3) controls (n=23) given only standard intravenous and oral analgesia. The primary endpoint was opioid analgesic consumption. The secondary endpoints were pain (numeric rating scale 0-10) and PONV (scale 0-3, where 0=no PONV and 3=severe PONV). Assessments were made up to 48 hours postoperatively.

RESULTS

The groups did not significantly differ in opioids consumption and reported pain at 1, 2, 24, and 48 hours postoperatively. PONV in the QLB group was lower than in the placebo and control groups.

CONCLUSION

Preoperative anterior QLB for laparoscopic cholecystectomy did not affect postoperative opioid requirements and pain. However, anterior QLB may decrease PONV.

Distribution of injectates in the thoracic paravertebral space of the dog and cat: A cadaveric study

Background:

Thoracic paravertebral block (TPVB) entails injecting a local anesthetic inside the thoracic paravertebral space (TPVS). Loss of resistance to air injection (air-LOR) was the first technique described in humans to locate the TPVS. To date, no study has investigated the spread of any substance after injection into the TPVS using the air-LOR technique nor has described the cranial and caudal limits of the space.

Aim:

To identify the boundaries of the TPVS, to determine whether the air-LOR technique is reliable for the identification of the TPVS and to examine the relationship between the volume of injectate and its spread.

Methods:

After a preliminary phase, the thorax of five cat and five dog cadavers was accessed and eviscerated. After TPVS probing, the polyurethane foam was injected, and the cranial and caudal borders were recorded after its maximum spread. Different volumes of a mixture of new methylene blue and ioversol were injected in the TPVS after its localization with a Tuohy needle and air-LOR technique in fourteen dog and six cat cadavers. Lateral radiographs of the vertebral column were used to document needle positioning, spread pattern and extension. The thorax of these subjects was then accessed and eviscerated to observe and record the spread of the mixture.

Results:

Injecting a dye into the TPVS, localized by an air-LOR technique, resulted in multi-segmental and often bilateral subpleural staining of paravertebral, intercostal, and dorsal mediastinal structures in dog and cat cadavers. The lateral radiographs most often showed a mixed cloud-like and linear spread pattern, which could be a predictor of the longitudinal spread of the dye. The foam injected into the TPVS at the cranial and the caudal level revealed anatomical communication with the cervical, axillar, and lumbar paravertebral regions.

Conclusion:

TPVS localization by air-LOR technique and injection results in a longitudinal multi-segmental spread in dog and cat cadavers. The communication of the TPVS with the axillary and lumbar regions could be of clinical interest for the brachial plexus and the lumbar intercostal nerve blocks in a clinical setting.

Effects of quadratus lumborum block regional anesthesia on postoperative pain after colorectal resection: a randomized controlled trial

INTRODUCTION

Postoperative pain following colorectal surgery is associated with a significant use of opioids. Recently, regional anesthesia, such as the posterior quadratus lumborum block (QL2), has been proposed to improve pain relief and reduce opioid use. However, the benefit of the QL2 on postoperative pain control remains controversial.

METHODS

We conducted a randomized controlled trial of patients undergoing colorectal surgery at the CHU de Québec-Université Laval. Patients were randomized to regional QL2 anesthesia with 150 mg of ropivacaine combined with standard analgesia or to QL2 with a sham intervention and standard analgesia. Our primary outcome was postoperative opioid administration at 24 h. Secondary outcomes included opioid administration in the post-anesthesia care unit (PACU), at 48 h and at hospital discharge, postoperative pain scores, delay in resumption of intestinal transit, nausea and vomiting, and hospital length of stay.

RESULTS

A total of 62 patients were enrolled from November 2017 to February 2018. QL2 regional anesthesia compared with a sham intervention was not associated with a reduction in postoperative morphine dose equivalent (100.2 mg, 95% CI 68.9-131.5 versus 88.7 mg, 95% CI 59.3-118.0, p = 0.81, respectively). Compared to QL2 regional anesthesia, postoperative pain scores in the control group were lower although statistical significance was not consistent for all postoperative time points. Other secondary outcomes were comparable between both groups.

CONCLUSION

We did not observe a reduction in postoperative opioid administration at 24 h with a posterior quadratus lumborum block regional anesthesia in patients undergoing elective colorectal surgery.

Analgesic effect of the ultrasound-guided subcostal approach to transmuscular quadratus lumborum block in patients undergoing laparoscopic nephrectomy: a randomized controlled trial

Background

Quadratus lumborum block (QLB) is an effective analgesia that lowers opioid consumption after lower abdominal and hip surgeries. The subcostal approach to transmuscular QLB is a novel technique that can provide postoperative analgesia by blocking more dermatomes. The aim of this study is to evaluate the efficacy and viability of subcostal approach to QLB after laparoscopic nephrectomy.

Methods

Sixty patients who underwent laparoscopic nephrectomy were randomly divided into the subcostal approach to QLB group (QLB group, n = 30) and the control group (C group, n = 30). All patients underwent ultrasound-guided subcostal approach to QLB in an ipsilateral parasagittal oblique plane at the L1–L2 level. The QLB group received 0.4 cc/kg of 0.3% ropivacaine, and the C group received 0.4 cc/kg of 0.9% saline. Postoperatively, a patient-controlled intravenous analgesic pump with sufentanil was attached to all the patients. The primary outcome was sufentanil consumption within the first 24 h after surgery. The secondary outcomes included the Ramsey sedation scale (RSS) scores and Bruggemann comfort scale (BCS) scores 6 h (T1), 12 h (T2), and 24 h (T3) after surgery, intraoperative remifentanil consumption, number of patients requiring rescue analgesia, time to recovery of intestinal function, mobilization time after surgery, and presence of side effects.

Results

Sufentanil consumption within the first 24 h after surgery was significantly lower in the QLB group than in the C group (mean [standard deviation]: 34.1 [9.9] μg vs 42.1 [11.6] μg, P = .006). The RSS scores did not differ between the two groups, and the BCS scores of the QLB group at T1 and T2 time points was significantly higher than those of the C group(P<0.05). The consumption of remifentanil intraoperatively and the number of patients requiring rescue analgesia were significantly lower in the QLB group (P<0.05). Time to recovery of intestinal function and mobilization time after surgery were significantly earlier in the QLB group (P<0.05). The incidence of postoperative nausea and vomiting was significantly lower in the QLB group (P<0.05).

Conclusions

The ultrasound-guided subcostal approach to QLB is an effective analgesic technique in patients undergoing laparoscopic nephrectomy as it reduces the consumption of sufentanil postoperatively.

Trial registration

ChiCTR1800020296 0 (Prospective registered). Initial registration date was 22/12/2018.

Quadratus Lumborum Block: Anatomical Concepts, Mechanisms, and Techniques

A review of anatomy, potential mechanisms of action, and techniques and summary of clinical evidence for quadratus lumborum block.

Boundaries of the thoracic paravertebral space: potential risks and benefits of the thoracic paravertebral block from an anatomical perspective

Purpose

Thoracic paravertebral block (TPVB) may be an alternative to thoracic epidural analgesia. A detailed knowledge of the anatomy of the TPV-space (TPVS), content and adnexa is essential in understanding the clinical consequences of TPVB. The exploration of the posterior TPVS accessibility in this study allows (1) determination of the anatomical boundaries, content and adnexa, (2) description of an ultrasound-guided spread of low and high viscous liquid.

Methods

In two formalin-fixed specimens, stratification of the several layers and the 3D-architecture of the TPVS were dissected, observed and photographed. In a third unembalmed specimen, ultrasound-guided posterolateral injections at several levels of the TPVS were performed with different fluids.

Results

TPVS communicated with all surrounding spaces including the segmental dorsal intercostal compartments (SDICs) and the prevertebral space. TPVS transitions to the SDICs were wide, whereas the SDICs showed narrowed transitions to the lateral intercostal spaces at the costal angle. Internal subdivision of the TPVS in a subendothoracic and an extra-pleural compartment by the endothoracic fascia was not observed. Caudally injected fluids spread posteriorly to the costodiaphragmatic recess, showing segmental intercostal and slight prevertebral spread.

Conclusions

Our detailed anatomical study shows that TPVS is a potential space continuous with the SDICs. The separation of the TPVS in a subendothoracic and an extra-pleural compartment by the endothoracic fascia was not observed. Based on the ultrasound-guided liquid spread we conclude that the use of a more lateral approach might increase the probability of intravascular puncture or catheter position.

Laparoscopic-guided psoas blockade as a novel analgesic method during inguinal herniorrhaphy: a clinical trial

BACKGROUND

Under laparoscopic guidance, block of ilioinguinal, iliohypogastric, and genitofemoral nerves can be possible with anesthetic injection in the plane between psoas major and the fasciae covering its anterior aspects [laparoscopic-assisted psoas (LAP) blockade]. This observer-blinded trial aimed to compare the opioid-sparing effect of LAP block with transversus abdominis plane (TAP) block after laparoscopic inguinal herniorrhaphy.

METHODS

Forty-five male patients were randomly assigned to receive LAP block, group LAP (n = 23), or ultrasound-guided TAP block, group TAP (n = 22). Primary outcome measure was the analgesic requirements in the first 36 post-operative hours. Post-operative pain scores and sensory blockade were recorded.

RESULTS

Median (interquartile range) total morphine requirement was significantly less in patients who underwent LAP blockade 0 (0, 4) than in patients who underwent TAP blockade 21 (10, 27; P < 0.001). LAP group showed significantly less pain at rest and on coughing compared with TAP group. The median number of dermatomes blocked was 3 (2-4) in LAP group and 3 (3-4) in TAP group (P < 0.05). The highest sensory-level blockade was at T12 (T11-L1) in LAP group, while it was at T10 (T10-T11) in TAP group. The most distal dermatome involvement was at L2 (L2-L2) in LAP group and at L1 (T12-L1) in TAP group.

CONCLUSION

A single injection LAP blockade significantly reduces the post-operative analgesic requirements and provides longer pain relief compared with TAP block after laparoscopic inguinal herniorrhaphy.

Anatomical Relationship between Bl23 and the Posterior Ramus of the L2 Spinal Nerve

Background

The acupuncture point BL23 is located in the region of the posterior ramus of the second lumbar spinal nerve (L2) and has historically been used to treat conditions such as lower back pain, pollakiuria, erectile dysfunction, dysmenorrhoea, tinnitus, and vertigo. Some of these treatment effects have been hypothesised to be mediated by the sympathetic nervous system. It was recently discovered that the posterior ramus of the spinal nerve (PRSN) at L2 forms not two but three branches.

Objective

To examine the relationship between the acupuncture point BL23 and the L2 PRSN in order to consider the pathways possibly affected by BL23 acupuncture.

Methods

Acupuncture needles were inserted through the skin at BL23 to a depth of 3 cm a total of 13 times in eight donor cadavers (seven right-sided, six left-sided). Leaving the needle in place, ventral dissection was performed to determine the PRSN anatomy between the L1 and L3 spinal segments. In four cadavers, the relationship between the L2 spinal nerve and sympathetic branches was additionally evaluated. Following dissection, three-dimensional (3D) data were acquired using a photo scanner and 3D structural images were created using 3D computer graphics software. One additional (female) cadaver was studied without insertion of an acupuncture needle (due to significant scoliosis).

Results

The L2 PRSN was divided into medial, intermediate and lateral branches. The needle inserted at BL23 came to lie in the region of the intermediate or lateral branches in all cases. Rami communicantes were found between the L2 spinal nerve and sympathetic trunk with fibres going on to supply the superior hypogastric plexus.

Conclusions

Our findings suggest that acupuncture needles inserted at BL23 come into close proximity with the intermediate or lateral branch of the L2 PRSN, which could result in stimulation of both the somatic and sympathetic nervous systems.

Different Approaches to Ultrasound-guided Thoracic Paravertebral Block: An Illustrated Review

Given the fast development and increasing clinical relevance of ultrasound guidance for thoracic paravertebral blockade, this review article strives (1) to provide comprehensive information on thoracic paravertebral space anatomy, tailored to the needs of a regional anesthesia practitioner, (2) to interpret ultrasound images of the thoracic paravertebral space using cross-sectional anatomical images that are matched in location and plane, and (3) to briefly describe and discuss different ultrasound-guided approaches to thoracic paravertebral blockade. To illustrate the pertinent anatomy, high-resolution photographs of anatomical cross-sections are used. By using voxel anatomy, it is possible to visualize the needle pathway of different approaches in the same human specimen. This offers a unique presentation of this complex anatomical region and is inherently more realistic than anatomical drawings.

Lumbar paravertebral blockade as intractable pain management method in palliative care

Optimal symptoms control in advanced cancer disease, with refractory to conventional pain treatment, needs an interventional procedure. This paper presents coadministration of local anesthetic (LA) via paravertebral blockade (PVB) as the alternative to an unsuccessful subcutaneous fentanyl pain control in a 71-year old cancer patient with pathological fracture of femoral neck, bone metastases, and contraindications to morphine. Bupivacaine in continuous infusion (0.25%, 5 mL · hour⁻¹) or in boluses (10 mL of 0.125%–0.5% solution), used for lumbar PVB, resulted in pain relief, decreased demand for opioids, and led to better social interactions. The factors contributing to an increased risk of systemic toxicity from LA in the patient were: renal impairment; heart failure; hypoalbuminemia; hypocalcemia; and a complex therapy with possible drug-drug interactions. These factors were taken into consideration during treatment. Bupivacaine’s side effects were absent. Coadministered drugs could mask LA’s toxicity. Elevated plasma α1-acid glycoprotein levels were a protective factor. To evaluate the benefit-risk ratio of the PVB treatment in boluses and in constant infusion, bupivacaine serum levels were determined and the drug plasma half-lives were calculated. Bupivacaine’s elimination was slower when administered in constant infusion than in boluses (t_½ = 7.80 hours versus 2.64 hours). Total drug serum concentrations remained within the safe ranges during the whole treatment course (22.9–927.4 ng mL⁻¹). In the case presented, lumbar PVB with bupivacaine in boluses (≤ 137.5 mg · 24 hours⁻¹) was an easy to perform, safe, effective method for pain control. Bupivacaine in continuous infusion (≤150 mg · 12 hours⁻¹) had an acceptable risk-benefits ratio, but was ineffective.

A review of the thoracic splanchnic nerves and celiac ganglia

Anatomical variation of the thoracic splanchnic nerves is as diverse as any structure in the body. Thoracic splanchnic nerves are derived from medial branches of the lower seven thoracic sympathetic ganglia, with the greater splanchnic nerve comprising the more cranial contributions, the lesser the middle branches, and the least splanchnic nerve usually T11 and/or T12. Much of the early anatomical research of the thoracic splanchnic nerves revolved around elucidating the nerve root level contributing to each of these nerves. The celiac plexus is a major interchange for autonomic fibers, receiving many of the thoracic splanchnic nerve fibers as they course toward the organs of the abdomen. The location of the celiac ganglia are usually described in relation to surrounding structures, and also show variation in size and general morphology. Clinically, the thoracic splanchnic nerves and celiac ganglia play a major role in pain management for upper abdominal disorders, particularly chronic pancreatitis and pancreatic cancer. Splanchnicectomy has been a treatment option since Mallet-Guy became a major proponent of the procedure in the 1940s. Splanchnic nerve dissection and thermocoagulation are two common derivatives of splanchnicectomy that are commonly used today. Celiac plexus block is also a treatment option to compliment splanchnicectomy in pain management. Endoscopic ultrasonography (EUS)-guided celiac injection and percutaneous methods of celiac plexus block have been heavily studied and are two important methods used today. For both splanchnicectomies and celiac plexus block, the innovation of ultrasonographic imaging technology has improved efficacy and accuracy of these procedures and continues to make pain management for these diseases more successful.

Potential foramen to allow communication between the pleural cavity and retroperitoneal space during laparoscopic surgery: a cadaver study of Bochdalek’s triangle

The indications for laparoscopic retroperitoneal surgery have recently been greatly extended and the technique has become popular, but concomitant pleural injury or pneumothorax has been reported from numerous hospitals in Japan. Which anatomical information is useful to avoid surgical injury of the suggested weak portion of the diaphragm? We identified a diaphragm-free triangular area or Bochdalek's triangle in 90.1% of elderly Japanese cadavers (100/111 cadavers), comprising about 622.8 mm(2) in area (height 47.9 mm, base 25.0 mm). In most cases (80.1%; 129/161), the entire triangle was restricted to the superior side of the 12th rib in addition to the medial side of the distal end of the rib. A "potential foramen" (PF) was defined as the diaphragm-free triangle >100 mm(2) in area on the parietal pleura. Most triangles (77.6%, 125/161) met this criterion. The PF was often covered by the kidney (93.3%), and had a mean area of 318.9 mm(2). The PF was located 42.3 mm from the distal end of the 12th rib, while the inferior pleural margin was 27.8 mm superior to the rib end. When the triangle was large, the PF was also large, with the PF often occupying >50% of the triangle area (62/125; 49.6%). To avoid the distal end of the 12th rib, in laparoscopic retroperitoneal surgery, we recommend making a transverse skin incision at the midpoint between the end of the 12th rib and the iliac crest.

Lumbar plexus blockade with ropivacaine for postoperative pain management in elderly patients undergoing urologic surgeries

BACKGROUND/AIMS

We evaluated the effectiveness and safety of lumbar plexus blockade with ropivacaine for postoperative pain relief in elderly patients undergoing flank incision for urological surgery.

METHODS

60 urological patients (>65 years old) were chosen randomly for paravertebral lumbar blockade. Postoperatively ropivacaine was used in group I (n = 30) and bupivacaine was administered in group II (n = 30) for lumbar plexus blockade. Heart rates, systolic and diastolic blood pressures, peripheral oxygen saturations, analgesia levels with visual analogue scales (VAS) were measured postoperatively at 5 and 30 min and 1, 3, 6, 8,and 12 h. Patient satisfaction scores and complications were recorded.

RESULTS

The hemodynamic parameters of the groups were in the normal ranges (p > 0.05). VAS were significantly decreased at 60 min in both groups (p < 0.05) and no important increase was observed during the first 8 h (p > 0.05). After the 8-hour measurement, analgesic was given to 7 patients in group I and 6 patients in group II (p < 0.05). There were no complications (p > 0.05). Patient satisfaction scores were found to be higher for all patients (p > 0.05).

CONCLUSION

In elderly patients, lumbar plexus blockade with ropivacaine can be a simple, safe and effective analgesic technique especially in the early postoperative period after urologic surgeries with flank incision.

In with the new, out with the old? Comparison of two approaches for psoas compartment block

We compared the approaches of Winnie and Capdevila for psoas compartment block (PCB) performed by a single operator in terms of contralateral spread, lumbar plexus blockade, and postoperative analgesic efficacy. Sixty patients underwent PCB (0.4 mL/kg levobupivacaine 0.5%) and subsequent spinal anesthesia for primary joint arthroplasty (hip or knee) in a prospective, double-blind study. Patients were randomly allocated to undergo PCB by using the Capdevila (group C; n = 30) or a modified Winnie (group W; n = 30) approach. Contralateral spread and lumbar plexus blockade were assessed 15, 30, and 45 min after PCB. Contralateral spread (bilateral from T4 to S5) and femoral and lateral cutaneous nerve block were evaluated by sensory testing, and obturator motor block was assessed. Bilateral anesthesia occurred in 10 patients in group C and 12 patients in group W (P = 0.8). Blockade of the femoral, lateral cutaneous, and obturator nerves was 90%, 93%, and 80%, respectively, for group C and 93%, 97%, and 90%, respectively, for group W (P > 0.05). No differences were found in PCB procedure time, pain scores, 24-h morphine consumption, or time to first morphine analgesia.

Varying anatomical injection points within the thoracic paravertebral space: effect on spread of solution and nerve blockade

The factors responsible for the spreading pattern of a single paravertebral injection are still uncertain. In this study, 28 patients were randomly assigned to receive a paravertebral injection of radio-opaque dye (10 ml, with or without co-administration of 20 ml of local anaesthetics) either dorsal or ventral to the endothoracic fascia. The point of injection was determined by use of a nerve-stimulator and the radiographic distribution pattern was assessed blindly by a radiologist. Injections made in the more ventral part of the thoracic paravertebral space, supposedly anterior to the endothoracic fascia, resulted in a multisegmental longitudinal spreading pattern, whereas injections made dorsal to the endothoracic fascia resulted in a less predictable cloud-like spreading pattern, with only limited distribution over adjacent segments. The use of a nerve stimulator-guided technique appears to enhance the likelihood of achieving the more desirable longitudinal spreading pattern.

Pathways of anesthetic from the thoracic paravertebral region to the celiac ganglion

Communication between the lower thoracic paravertebral region and the celiac ganglion through the retrocrural space was investigated. After dye was injected into the endothoracic fascia in the lower thoracic paravertebral region at the T11 level, its spread to the celiac ganglion was examined in fifteen cadavers. The dye reached the celiac ganglion in nine cadavers (60%) by passing through the retrocrural space, along the greater and lesser splanchnic nerves and through the split in the crus of the diaphragm through which the splanchnic nerves traveled. In the remaining six cadavers, dye spread toward the ganglion along the crus of the diaphragm. In three living subjects the spread of a radio-opaque dye injected in the same manner was studied using 3D-computed tomography. This study confirmed that the radio-opaque dye traveled toward the celiac ganglion along the crus of the diaphragm. From our results we suggest that a fluid communication may exist between the lower thoracic paravertebral region and the celiac ganglion in cadavers and in living humans and that clinicians should be aware of this possible route of spread when administering lower thoracic paravertebral anesthesia.