Cadaveric feasibility study on the use of ultrasound contrast to assess spread of injectate in the serratus anterior muscle plane

Ultrasound-guided serratus anterior plane block enhances postoperative analgesia and recovery in thoracoscopic surgery

BACKGROUND

The serratus anterior muscle, located in the lateral aspect of the thorax, plays a crucial role in shoulder movement and stability. Thoracoscopic surgery, while minimally invasive, often results in significant postoperative pain, complicating patient recovery and potentially extending hospital stays. Traditional anesthesia methods may not adequately address this pain, leading to increased complications such as agitation due to inadequate pain management.

AIM

To evaluate the application value of ultrasound-guided serratus anterior plane block (SAPB) in patients undergoing thoracoscopic surgery, focusing on its effects on postoperative analgesia and rehabilitation.

METHODS

Eighty patients undergoing thoracoscopic surgery between August 2021 and December 2022 were randomly divided into two groups: An observation group receiving ultrasound-guided SAPB and a control group receiving standard care without SAPB. Both groups underwent general anesthesia and were monitored for blood pressure, heart rate (HR), oxygen saturation, and pulse. The primary outcomes measured included mean arterial pressure (MAP), HR, postoperative visual analogue scale (VAS) scores for pain, supplemental analgesic use, and incidence of agitation.

RESULTS

The observation group showed significantly lower cortisol and glucose concentrations at various time points post-operation compared to the control group, indicating reduced stress responses. Moreover, MAP and HR levels were lower in the observation group during and after surgery. VAS scores were significantly lower in the observation group at 1 h, 4 h, 6 h, and 12 h post-surgery, and the rates of analgesic supplementation and agitation were significantly reduced compared to the control group.

CONCLUSION

Ultrasound-guided SAPB significantly improves postoperative analgesia and reduces agitation in patients undergoing thoracoscopic surgery. This technique stabilizes perioperative vital signs, decreases the need for supplemental analgesics, and minimizes postoperative pain and stress responses, underscoring its high application value in enhancing patient recovery and rehabilitation post-thoracoscopy.

Fascial plane blocks for cardiothoracic surgery: a narrative review

In recent years, there has been a growing awareness of the limitations and risks associated with the overreliance on opioids in various surgical procedures, including cardiothoracic surgery.This shift on pain management toward reducing reliance on opioids, together with need to improve patient outcomes, alleviate suffering, gain early mobilization after surgery, reduce hospital stay, and improve patient satisfaction and functional recovery, has led to the development and widespread implementation of enhanced recovery after surgery (ERAS) protocols.In this context, fascial plane blocks are emerging as part of a multimodal analgesic in cardiac surgery and as alternatives to conventional neuraxial blocks for thoracic surgery, and there is a growing body of evidence suggesting their effectiveness and safety in providing pain relief for these procedures. In this review, we discuss the most common fascial plane block techniques used in the field of cardiothoracic surgery, offering a comprehensive overview of regional anesthesia techniques and presenting the latest evidence on the use of chest wall plane blocks specifically in this surgical setting.

The Effect of Ultrasound-Guided Low Serratus Anterior Plane Block on Analgesia and Quality of Recovery After Robot-Assisted Thymectomy via Subxiphoid Approach: Study Protocol for a Randomized Controlled Trial

Purpose

Study Design and Methods

Discussion

The Role of Serratus Anterior Plane Block During in Video-Assisted Thoracoscopic Surgery

Although thoracoscopy has characteristics such as a small surgical incision and low stress response, post-surgical pain after a thoracoscopic operation is no less than that after a thoracotomy. Moreover, poor post-surgical pain management is likely to cause an increased incidence of postoperative pulmonary complications (PPCs) and chronic post-surgical pain. The serratus anterior plane block (SAPB) is a regional anesthesia method whereby local anesthetics (LAs) are injected into the serratus anterior space to block the lateral cutaneous branch of the intercostal nerve, long thoracic nerve, and dorsal thoracic nerve. The block range of the SAPB covers the incisions of video-assisted thoracoscopic surgery (VATS) and the site of the chest tube, which are often located in the antero-lateral chest wall. Therefore, the SAPB can achieve effective analgesia in VATS. For example, 0.125% to 0.25% levobupivacaine (20-25 ml) is widely used for thoracic surgery, which can achieve effective analgesia and avoid adverse reactions. Moreover, it has advantages compared with thoracic segmental epidural block (TEA) and thoracic paravertebral block (TPVB), such as simple operation, increased safety, fewer complications, and hemodynamic stability. In addition, adequate analgesia is helpful for pulmonary function recovery and reduces the incidence of PPCs. This article introduces the anatomical mechanism of the SAPB, diverse operation approaches, how to choose drugs and adjuvants, and the resulting impacted area range. It summarizes the advantages and disadvantages of the SAPB compared with other analgesic methods and posits that the SAPB is beneficial to the recovery of postoperative lung function, which provides more options for postoperative analgesia after VATS.

Serratus anterior plane versus paravertebral nerve blocks for postoperative analgesia after non-mastectomy breast surgery: a randomized controlled non-inferiority trial

Background

Paravertebral and serratus plane blocks are both used to treat pain following breast surgery. However, it remains unknown if the newer serratus block provides comparable analgesia to the decades-old paravertebral technique.

Methods

Subjects undergoing unilateral or bilateral non-mastectomy breast surgery were randomized to a single-injection serratus or paravertebral block in a subject-masked fashion (ropivacaine 0.5%; 20 mL unilateral; 16 mL/side bilateral). We hypothesized that (1) analgesia would be non-inferior in the recovery room with serratus blocks (measurement: Numeric Rating Scale), and (2) opioid consumption would be non-inferior with serratus blocks in the operating and recovery rooms. In order to claim that serratus blocks are non-inferior to paravertebral blocks, both hypotheses must be at least non-inferior.

Results

Within the recovery room, pain scores for participants with serratus blocks (n=49) had a median (IQR) of 4.0 (0–5.5) vs 0 (0–3.0) for those with paravertebral blocks (n=51): 0.95% CI −3.00 to −0.00; p=0.001. However, the difference in morphine equivalents did not reach statistical significance for superiority with the serratus group consuming 14 mg (10–19) vs 10 mg (10–16) for the paravertebral group: 95% CI −4.50 to 0.00, p=0.123. Since the 95% CI lower limit of −4.5 was less than our prespecified margin of −2.0, we failed to conclude non-inferiority of the serratus block with regard to opioid consumption.

Conclusions

Serratus blocks provided inferior analgesia compared with paravertebral blocks. Without a dramatic improvement in safety profile for serratus blocks, it appears that paravertebral blocks are superior to serratus blocks for postoperative analgesia after non-mastectomy breast surgery.

Trial registration number

NCT03860974.

Quality of recovery scores in deep serratus anterior plane block vs. sham block in ambulatory breast cancer surgery: a randomised controlled trial

Deep serratus anterior plane block has been widely adopted as an analgesic adjunct for patients undergoing breast surgery, but robust supporting evidence of efficacy is lacking. We randomly allocated 40 patients undergoing simple or partial mastectomy with sentinel node biopsy to receive either a pre-operative deep serratus anterior plane block (serratus group) or a placebo injection (sham group), in addition to systemic analgesia. The primary outcome measure was the quality of recovery score at discharge, as assessed by the quality of recovery-15 questionnaire at various time-points. Secondary analgesic outcomes included: pain severity; postoperative opioid consumption; opioid-related side-effects; patient satisfaction up to 7 days postoperatively; and persistent postoperative pain up to 3 months after surgery. All patients who were recruited completed the study. There were no differences in the quality of recovery-15 scores between patients in the serratus and control groups, with mean (SD) scores of 96 (14) and 102 (20) for the control and serratus groups, respectively. We were also unable to detect differences in any of the secondary analgesic outcomes examined. The addition of a deep serratus anterior plane block to systemic analgesia does not enhance quality of recovery in patients undergoing ambulatory breast cancer surgery.

Postoperative Thoracic Pain Treatment: Serratus Anterior or Erector Spinae Plane Block?

BACKGROUND

 Thoracic surgery is one of the most painful surgeries. Effective analgesia is important in postoperative pain management. In this study, we aimed to compare the two new fascial block techniques.

METHODS

 A total of 107 patients who underwent thoracic surgery between October 2018 and November 2019 were retrospectively evaluated. The study included 59 patients in the serratus anterior plane block (SAPB) group and 48 patients in the erector spinae plane block (ESPB) group. Both groups were administered 30 mL of 0.25% bupivacaine and their morphine consumption was evaluated by a patient-controlled analgesia (PCA) method during the 2nd, 6th, 12th, 24th, and 48th postoperative hours. Pain was measured with the visual analog scale (VAS). Intraoperative mean arterial pressure (MAP) and heart rate (HR) were recorded.

RESULTS

 During the first 24 hours, VAS values were significantly lower in the ESPB group (p < 0.05). Moreover, morphine consumption was significantly lower in the ESPB group in the 24th and 48th hours (p < 0.05). Intraoperative remifentanil consumption was also significantly lower in the ESPB group (p < 0.05). Intraoperative MAP in the ESPB group was found to be significantly lower after the 4th hour. HR was similar in both groups.

CONCLUSION

 ESPB was more effective compared with SAPB in postoperative thoracic pain management.

Evaluation of postoperative pain in patients undergoing modified radical mastectomy with pectoralis or serratus-intercostal fascial plane blocks

Background

Regional nerve blocks are an integral part of multimodal analgesia and should be chosen based on their efficacy, convenience, and minimal side effects. Here, we compare the use of pectoral (PEC II) and serratus-intercostal fascial plane (SIFP) blocks in breast carcinoma cases undergoing modified radical mastectomy in terms of the postoperative analgesic efficacy and shoulder mobility.

Methods

The primary outcome of this prospective controlled study was to compare the postoperative static and dynamic pain scores, and the secondary outcome was to assess the shoulder pain, range of shoulder joint motion, and hemodynamic parameters. Sixty patients were randomly allocated to three groups and given general anesthesia. All patients received paracetamol, diclofenac, and rescue doses of tramadol based on the institute's acute pain service policy. No block was performed in group C (control), whereas groups P and S received PEC II and SIFP blocks, respectively, before surgical incision.

Results

The groups were comparable in terms of age, weight, height, and body mass index distribution. Dynamic pain relief was significantly better 12 and 24 h postoperatively in groups P (P = 0.034, P = 0.040 respectively) and S (P = 0.012 and P = 0.017, respectively) compared to group C. Shoulder pain relief and shoulder mobility were better in group S, while the hemodynamic parameters were more stable in group P.

Conclusions

Both SIFP and PEC blocks have comparable dynamic and static pain relief with better shoulder pain scores in patients receiving SIFP.

Analgesic efficacy and spread of local anesthetic in ultrasound-guided paravertebral, pectoralis II, and serratus anterior plane block for breast surgeries: A randomized controlled trial

Background

Thoracic paravertebral block (TPVB) has become the gold standard to provide postoperative analgesia in breast surgery. Recently, ultrasound-guided (USG) pectoralis (PECS) block and serratus anterior plane (SAP) block have been described as an alternative to TPVB. The objectives were to compare TPVB, PECS, and SAP block in terms of analgesic efficacy and the spread of local anesthetic by ultrasound imaging, correlating it with the sensory blockade.

Materials and Methods

Prospective randomized interventional study conducted in 45 ASA grades I-II patients scheduled for the elective breast surgery. Patients were randomly allocated into three groups, i.e., Gr.1 (USG -TPVB) (ropivacaine 0.375% 20 ml), Gr.2 (USG-PECS II) block (ropivacaine 0.375% 30 ml), and Gr.3 (USG-SAP) (ropivacaine 0.375% 30 ml). Spread of the local anesthetics was seen with ultrasound imaging. Onset of sensory blockade, postoperative fentanyl consumption, and pain scores was measured.

Results

TPVB and SAP group had comparatively higher spread and sensory block compared to PECS group. Postoperative fentanyl requirement (mean ± SD) was 428.33 ± 243.1 μg, 644.67 ± 260.15 μg, and 415 ± 182.44 μg in the TPVB group, PECS II group, and SAP group, respectively. SAP group had significantly lesser requirement than PECS II group (P = 0.028) but similar requirement as in TPVB group (P = 1.0). Pain scores were not significantly different among the group in the postoperative period.

Conclusion

TPVB and SAP group result in a greater spread of the drug and provide equivalent analgesia and are superior to the PECS II block in providing analgesia for breast surgeries. SAP block is easier to perform than TPVB with lesser chances of complications and results in faster onset.

Impact of serratus plane block on pain scores and incentive spirometry volumes after chest trauma

Background: Adequate pain control is difficult to achieve in patients with multiple rib fractures (MRF). Serratus plane block (SPB) is a novel technique for alleviating rib fracture pain. Several published case reports support this hypothesis. Purpose: The purpose of this study was to evaluate the use of SPB in MRF at our level 1 trauma center. Methods: Our hospital's Regional Anesthesia Registry was queried for all trauma patients with MRF who underwent SPB between August 2014 and January 2018. Data were compared in each patient as a matched pair for the time periods before and after undergoing SPB. Thirty-four patients with similar baseline characteristics were enrolled. Results: The median number of rib fractures was 7. Ordinal pain scores were found to be improved 4 hrs after SPB from median 7/10 to 3/10 (P<0.001). Incentive spirometry (IS) volumes recorded 4 and 24 hrs postserratus plane block showed a median increase of 150 and 175 mL from baseline, respectively (P<0.001). IS volumes recorded at 48 hrs showed a median increase of 300 mL from baseline (P<0.001). Respiratory rate decreased from a median value of 24.5 to 16 breaths/min (P<0.001). SpO₂ was improved at 24 hrs from median 96% to 99% (P<0.001). Conclusion: SPB improves pain scores and IS volumes in MRF. Because it is not limited by patient positioning or anticoagulation and has a better safety profile, it may offer a viable alternative to neuraxial techniques. Additional studies are necessary to evaluate its efficacy compared to neuraxial techniques.

Interspace between Popliteal Artery and posterior Capsule of the Knee (IPACK) Injectate Spread: A Cadaver Study

OBJECTIVES

Local anesthetic injection into the interspace between the popliteal artery and the posterior capsule of the knee (IPACK) has the potential to provide motor-sparing analgesia to the posterior knee after total knee arthroplasty. The primary objective of this cadaveric study was to evaluate injectate spread to relevant anatomic structures with IPACK injection.

METHODS

After receipt of Institutional Review Board Biospecimen Subcommittee approval, IPACK injection was performed on fresh-frozen cadavers. The popliteal fossa in each specimen was dissected and examined for injectate spread.

RESULTS

Ten fresh-frozen cadaver knees were included in the study. Injectate was observed to spread in the popliteal fossa at a mean ± SD of 6.1 ± 0.7 cm in the medial-lateral dimension and 10.1 ± 3.2 cm in the proximal-distal dimension. No injectate was noted to be in contact with the proximal segment of the sciatic nerve, but 3 specimens showed injectate spread to the tibial nerve. In 3 specimens, the injectate showed possible contact with the common peroneal nerve. The middle genicular artery was consistently surrounded by injectate.

CONCLUSIONS

This cadaver study of IPACK injection demonstrated spread throughout the popliteal fossa without proximal sciatic involvement. However, the potential for injectate to spread to the tibial or common peroneal nerve was demonstrated. Consistent surrounding of the middle genicular artery with injectate suggests a potential mechanism of analgesia for the IPACK block, due to the predictable relationship between articular sensory nerves and this artery. Further study is needed to determine the ideal site of IPACK injection.

Interfascial block at the serratus muscle plane versus conventional analgesia in breast surgery: a randomized controlled trial

Background and objectives

In the context of opioid-sparing perioperative management, there is still little evidence from randomized controlled trials regarding the effectiveness of interfascial thoracic blocks. This study hypothesizes that receiving a serratus plane block reduces opioid requirements, pain scores, and rescue medication needs.

Methods

This double-blind, randomized controlled study was conducted on 60 adult females undergoing oncologic breast surgery. After general anesthesia, patients were randomly allocated to either conventional analgesia (control group, n=30) or single-injection serratus block with L-bupivacaine 0.25% 30mL (study group, n=30). First 24-hour total morphine consumption (primary outcome), pain scores at 1, 3, 6, 12, and 24 hours, time-to-first opioid rescue analgesia, and adverse effects were recorded.

Results

Median 24 hours’ opioid dose was greater in the control group (median difference 9 mg (95% CI 4 to 14.5 mg); p<0.001). Proportional odds model showed that the study group has a lower probability of receiving opioid drugs (OR=0.26 (95% CI 0.10 to 0.68); p<0.001), while mastectomies have a higher probability of receiving them (OR=4.11 (95% CI 1.25 to 13.58); p=0.002). Pain scores in the study group were significantly lower throughout the follow-up period (p<0.001). Control group subjects needed earlier morphine rescue and had a higher risk of rescue dose requirement (p=0.002).

Conclusions

Interfascial serratus plane block reduces opioid requirements and is associated with better pain scores and lower and later rescue analgesia needs in the first 24 hours, compared with conventional intravenous analgesia, in breast surgery.

Trial registration number

NCT02905149.

Serratus anterior plane block for minimal invasive heart surgery

BACKGROUND

Minimal invasive heart surgery (MIHS) presents several benefits, but provides intense and prolonged post-operative pain. Our objective was to compare efficacy of serratus anterior plane block (SAPB) with continuous wound infiltration (CWI) for management of post-operative pain following MIHS.

METHODS

It's retrospective, monocentric study between November 2016 to April 2017. The study was performed at the University hospital of Dijon, Burgundy, France. All patients scheduled for MIHS was included. Data was collected retrospectively. During this period, 20 patients had SAPB and 26 had CWI. SAPB was performed before extubation with a single injection of 0.5 mg/kg of ropivacaïne (5 mg/ml). In the CWI group, catheter was inserted in the subcutaneous space by the surgeon at the end of the procedure. A 10 ml bolus of ropivacaïne (7.5 mg/mL) was followed by a continuous infusion (2 mg/ml) between 7 and 12 ml/h for 48 h. Morphine consumption and visual analog score (VAS) were recorded for 48 h. Length of stay in intensive care unit and hospital was also collected.

RESULTS

Morphine consumption and VAS score were significantly lower in SAPB group (p < 0.01). Length of stay in intensive care and hospital was significantly was decreased in SAPB group.

CONCLUSION

SAPB appears effective in reducing postoperative MIHS pain.

Radiological study to evaluate the spreading of two volumes (10 vs. 20ml) of radiological contrast in the block of cutaneous branches of intercostal nerves in medial axillary line (BRILMA) in a porcine experimental model

OBJECTIVE

Interfascial blocks of the thoracic wall are being developed as an alternative to central blocks in breast surgery. However, there are few studies that have evaluated the anatomical extension of the local anaesthetic. The objective of this study was to analyse, using fluoroscopy, the spreading of two volumes (10 vs. 20ml) of radiological contrast in the serratus-intercostal plane block in an experimental pig model.

MATERIAL AND METHODS

Ten Large-White breed pigs were selected to have a bilateral ultrasound serratus-intercostal plane block performed, with the administering of 10ml and 20ml of iopamidol in the right and left hemithorax, respectively. The spreading of contrast was analysed by fluoroscopy. The Spearman test correlation was used to evaluate the relationship between the administered volume and radiological spreading. A value of P<.05 was considered significant.

RESULTS

Twenty anaesthetic blocks were performed, being able to analyse 18 of them. The administration of 10ml of contrast was associated with a mean spreading of 2.28±0.31 (95% CI; 2.01-2.54) intercostal spaces, while the administration of 20ml showed a spreading of 3±0.25 (95% CI; 2.81-3.18) intercostal spaces. There was a significant correlation between the injected volume and the spreading of the contrast (Spearman correlation coefficient of 0.81; P=.0001).

CONCLUSION

The results showed a spreading of volume subject to the serratus-intercostal plane block, although not maintaining a 1:1 ratio. Doubling the volume increased the blocked segments by 31%. These findings, if corroborated in the clinical practice, would allow a more precise adjustment in the anaesthetic volume administered.

The efficacy of serratus anterior plane block in analgesia for thoracotomy: a retrospective study

PURPOSE

A multimodal analgesic approach is necessary for post-thoracotomy pain, which can be severe. Intravenous access, central and peripheral nerve blocks are frequently used. The aim of this study was to evaluate the efficacy of serratus anterior plane block (SAPB) in the management of post-thoracotomy pain.

METHODS

A total of 40 patients who underwent thoracotomy between January 2014 and January 2016 were retrospectively analyzed. The patients were divided into two groups: Group M (intravenous patient-controlled analgesia morphine; n = 20) and Group S (intravenous patient-controlled analgesia morphine + SAPB; n = 20). The Visual Analogue Scale (VAS) was used for pain evaluation at the 1st, 2nd, 4th, 6th, 8th, 12th and 24th postoperative hours and morphine consumption was evaluated at the 6th, 12th and 24th postoperative hours. Secondary outcomes were additional analgesic requirement, side effects, the Ramsay Sedation Scale (RSS) scores, block onset time and block level.

RESULTS

The VAS scores and the amount of morphine consumed at the 6th, 12th and 24th hours were found to be significantly lower in Group S than in Group M (P < 0.001). No statistically significant difference was found in the rate of side effects, including nausea, vomiting, pruritus, respiratory depression, bradycardia and hypotension, and RSS outcomes between the groups.

CONCLUSION

Our study suggests that SAPB is an effective adjuvant treatment option for thoracotomy analgesia.

Analgesic efficacy of ultrasound-guided paravertebral block versus serratus plane block for modified radical mastectomy: A randomised, controlled trial

Background and Aims:

Modified radical mastectomy (MRM) may be associated with severe post-operative pain, leading to chronic pain syndrome. We compared the post-operative analgesic profile of two ultrasound-guided nerve blocks: Paravertebral block (PVB) and serratus plane block (SPB).

Methods:

This double-blind, randomised study was conducted on fifty adult females, scheduled for MRM with axillary dissection. After inducing general anaesthesia with intravenous midazolam 1 mg, fentanyl 1.5 mcg/kg, propofol 1–2 mg/kg and vecuronium 0.1 mg/kg, patients were administered either ultrasound-guided thoracic PVB at T4 (n = 25) or SPB at 5^th rib (n = 25) with 20 ml of 0.5% bupivacaine, both as a single level injection. Time to first rescue analgesia and morphine consumption in 4, 6, 24, 48 and 72 h by PCA pump, visual analogue scale score and any adverse effects were recorded. Quantitative variables were compared using the unpaired t-test or the Mann–Whitney U test between the two groups. Qualitative variables were compared using the Chi-square test or Fisher's exact test.

Results:

The duration of analgesia (mean ± Standard deviation [SD]) was significantly longer in the PVB group compared to SPB group (346 ± 57 min vs. 245.6 ± 58 min, P < 0.001). The post-operative 24 h morphine consumption (mean ± SD) was significantly higher in the SPB group (9.7 ± 2.1 mg) compared to PVB group (6.5 ± 1.5 mg) (P < 0.001).

Conclusion:

Ultrasound-guided SPB is an alternative analgesic technique to thoracic PVB for MRM although PVB provides a longer duration of analgesia.