Fascial Plane Blocks: More Questions Than Answers?

Acute Pain Management with Ultrasound-Guided Erector Spinae Plane Block and Serratus Anterior Plane Block in Patients Undergoing Coronary Artery Bypass via Mini-thoracotomy: A Randomized Controlled Trial

OBJECTIVE

This study was designed to examine the analgesic efficacy of erector spinae plane (ESP) block or combined ESP and superficial serratus anterior plane (SAP) block in patients undergoing elective coronary artery bypass via mini-thoracotomy.

DESIGN

Randomized controlled study.

SETTING

Operating room, intensive care unit, and ward.

PATIENTS

Fifty-four patients undergoing elective coronary artery bypass via mini-thoracotomy.

INTERVENTIONS

Eligible patients were randomly allocated to single-ESP block (ESP group) or combined ESP and superficial SAP block (ESP+SAP group).

MEASUREMENTS AND MAIN RESULTS

The primary outcome was dynamic numerical rating scale (NRS) scores (on coughing) for the surgical incision site 6 hours after skin closure. Secondary outcomes included dynamic NRS scores for surgical incision at 12, 18, 24, and 48 hours postoperatively plus NRS scores for the chest tube, hydromorphone consumption, quality of recovery, and adverse events within 48 hours postoperatively. The ESP+SAP group had lower dynamic NRS scores for surgical incision at postoperative 6 hours (mean difference: -2.1, 95% CI -2.8 to -1.4, adjusted p < 0.001) and 12 hours (-1.3, 95% CI -2.0 to -0.7, adjusted p < 0.001) compared to the ESP group. The ESP+SAP group also showed lower dynamic NRS scores for the chest tube at 6 hours (-1.4, 95% CI -2.0 to -0.9, adjusted p < 0.001) and 12 hours (-1.2, 95% CI -1.7 to -0.6, adjusted p < 0.001) postoperatively. Linear mixed-model analysis showed that NRS scores for the surgical incision and chest tube were lower in the ESP+SAP group compared to the ESP group (both p < 0.05).

CONCLUSION

Compared with ESP block alone, ESP combined with superficial SAP block reduced pain scores in patients undergoing coronary artery bypass via mini-thoracotomy.

Is the combination of interfascial plane blocks sufficient for awake breast cancer surgery? An observational, prospective, proof-of-concept study

INTRODUCTION

Breast cancer is the most prevalent cancer among women, often necessitating surgical intervention. While surgeries like lumpectomy can be performed under local anesthesia, more extensive procedures typically require general anesthesia. Awake breast cancer surgery has emerged as an alternative due to risks associated with general anesthesia and patient preference.

METHODS

This prospective observational study, conducted from July 2022 to July 2023, evaluated the effectiveness of ultrasound-guided fascial plane blocks for awake breast surgery. Patients aged 18-80 years undergoing unilateral breast surgery were included, following ethical committee approval and written informed consent. Exclusion criteria were prior breast surgery, coagulopathies, infections, allergies to local anesthetics, psychiatric disorders, body mass index over 40 kg/m², and chest deformities. The combination of interpectoral, pecto-serratus, and deep serratus plane blocks was used as the primary anesthetic method, with a superficial parasternal block added in cases where complete cutaneous coverage was not achieved.

RESULTS

Seventeen patients were enrolled. The primary outcome, sufficient surgical anesthesia without deep sedation, was achieved in 15 patients. The combination of the aforementioned blocks proved effective, with an average surgery duration of 59.66 min, and propofol requirements averaging 1.77 mg/kg/hour. Most patients reported high satisfaction levels, and no early or late block-related complications were observed.

CONCLUSION

The combination of fascial plane blocks is a viable option for awake breast cancer surgery, potentially eliminating the need for more invasive anesthesia techniques. Further studies are necessary to confirm these findings in larger, homogeneous patient groups.

Comparison of Analgesic Method in Laparoscopic Gastrectomy Using External Oblique Intercostal Block Versus Wound Infiltration: A Randomized Controlled Trial

Background: External oblique intercostal block (EOIB) is effective in relieving pain in the T6 to T10 dermatomes; however, there is limited evidence comparing EOIB with conventional regional anesthesia. In this randomized controlled trial, it was hypothesized that EOIB would provide more effective analgesia than wound infiltration (WI) in laparoscopic gastrectomy. Methods: Thirty-two patients (aged 20-85 years) with American Society of Anesthesiologists Performance Status of 1 to 2, scheduled for laparoscopic gastrectomy, were randomly divided into EOIB and WI groups. Both procedures were performed using 40 mL of 0.25% levobupivacaine. The primary outcome was the numerical rating scale (NRS) score 12 h postoperatively. Secondary outcomes were NRS at 2, 24, and 48 h postoperatively, variation in quality of recovery-15 score on postoperative days 1 and 2 from preoperative baseline, postoperative fentanyl consumption, and variation in World Health Organization Disability Assessment Scale 2.0 scores between baseline and 3 months postoperatively. Plasma concentrations of levobupivacaine and pinprick sensation in the T4-11 dermatomes post-EOIB were evaluated to determine the exploratory endpoints. Results: There were no differences in the NRS scores 12 h postoperatively at rest and during movement between the EOIB and WI groups (mean standard deviation 1.3 [1.1] vs. 1.5 [1.4] and 3.1 [1.6] vs. 3.8 [1.7], respectively). Secondary outcomes did not differ significantly between the groups. The time to peak plasma concentration of levobupivacaine following EOIB was 45 min. Conclusions: No significant differences in NRS scores were observed between the analgesic effects of EOIB and WI at 12 h postoperatively.

A progress of research on the application of fascial plane blocks in surgeries and their future direction: a review article

Fascial plane blocks (FPBs) are gaining popularity in clinical settings owing to their improved analgesia when combined with either traditional regional anesthesia or general anesthesia during the perioperative phase. The scope of study on FPBs has substantially increased over the past 20 years, yet the exact mechanism, issues linked to the approaches, and direction of future research on FPBs are still up for debate. Given that it can be performed at all levels of the spine and provides analgesia to most areas of the body, the erector spinae plane block, one of the FPBs, has been extensively studied for chronic rational pain, visceral pain, abdominal surgical analgesia, imaging, and anatomical mechanisms. This has led to the contention that the erector spinae plane block is the ultimate Plan A block. Yet even though the future of FPBs is promising, the unstable effect, the probability of local anesthetic poisoning, and the lack of consensus on the definition and assessment of the FPB's success are still the major concerns. In order to precisely administer FPBs to patients who require analgesia in this condition, an algorithm that uses artificial intelligence is required. This algorithm will assist healthcare professionals in practicing precision medicine.

Latest Advances in Regional Anaesthesia

Training and expertise in regional anaesthesia have increased significantly in tandem with increased interest over the past two decades. This review outlines the most recent advances in regional anaesthesia and focuses on novel areas of interest including fascial plane blocks. Pharmacological advances in the form of the prolongation of drug duration with liposomal bupivacaine are considered. Neuromodulation in the context of regional anaesthesia is outlined as a potential future direction. The growing use of regional anaesthesia outside of the theatre environment and current thinking on managing the rebound plane after regional block regression are also discussed. Recent relevant evidence is summarised, unanswered questions are outlined, and priorities for ongoing investigation are suggested.

Unilateral Sacral Erector Spinae Plane Block for Thigh Amputation: Case Report

Selection of anesthetic technique for thigh amputation is complicated by patients' comorbid conditions. The sacral erector spinae plane block (ESPB) is an emerging technique with potential as a primary anesthetic for thigh amputation. We detail a case involving a 79-year-old undergoing thigh amputation, where sacral ESPB proved insufficient, prompting a shift to spinal anesthesia. This instance underscores the necessity for further investigation into the reliability of the sacral ESPB for lower limb surgeries. Until such evidence is established, caution is advised in relying solely on the sacral ESPB for thigh amputations, and consideration of alternative techniques is recommended.

The efficacy of ultrasound-guided upper thoracic erector spinae plane block for postoperative analgesia in proximal shoulder surgery and its effect on phrenic nerve function: A prospective exploratory study

Background and Aims

The upper thoracic (T2) erector spinae plane block (UT-ESPB) has been proposed as an alternative to interscalene brachial plexus block for postoperative analgesia in shoulder surgery. The current study was conducted to evaluate the same.

Material and Methods

Patients scheduled for shoulder surgery under general anesthesia (GA) received ultrasound-guided UT-ESPB. The outcomes measured were diaphragmatic movements, block characteristics, and quality of recovery at 24 h.

Results

A total of 43 patients were recruited. The incidence of phrenic nerve palsy was 0%. The sensory level achieved by the maximum number of patients at the end of 30 min was C7-T5 level, and none had a motor block. Forty-two percent of patients did not require rescue analgesia till 24 h postoperative. In the rest of the patients, the mean (SD) duration of analgesia was 724.2 ± 486.80 min, and the mean postoperative requirement of fentanyl was 98.80 ± 47.02 μg. The median pain score (NRS) during rest and movement is 2 to 3 and 3 to 4, respectively. The median quality of recovery score at the end of 24 h after the block was 14 (15-14).

Conclusion

The upper thoracic ESPB resulted in a sensory loss from C7-T5 dermatomes without any weakness of the diaphragm and upper limb. However, the block was moderately effective in terms of the total duration of analgesia, postoperative pain scores, analgesic requirement, and quality of recovery in patients undergoing proximal shoulder surgeries under GA. Further studies are required to establish its role due to its poor correlation with sensory spread.

Factors to consider for fascial plane blocks' success in acute and chronic pain management

The outcome of fascial plane blocks (FPBs) has a certain variability that may depend on many factors, which can be divided into three main categories: operator-related, patient-related and drug-related. Operator-related factors include personal skills, choice of needle and injection modalities. Patient variables include anthropometric features, the type of targeted fascia, anatomical variants, patient positioning, muscle tone and breathing. Ultimately, efficacy, onset, and duration of fascial blocks may be affected by characteristics of the injected solution, including the type of local anesthetic, volume, concentration, pH, temperature and the use of adjuvants. In this article, we investigated all the factors that may influence the outcome of FPBs from a generic perspective, without focusing on any specific technique. Also, we provided suggestions to optimize techniques for everyday practitioners and insights to researchers for future studies.

Efficacy of modified thoracoabdominal nerve block through perichondrial approach following laparoscopic inguinal hernia repair surgery: a randomized controlled trial

BACKGROUND

Modified thoracoabdominal nerve block through perichondrial approach is a novel fascial plane block and provides abdominal analgesia by blocking thoracoabdominal nerves. Our primary aim was to evaluate the efficacy of M-TAPA on quality of recovery and pain scores in patients who underwent laparoscopic inguinal hernia repair surgery (Trans Abdominal Pre-Peritoneal approach ‒ TAPP).

METHODS

Patients with American Society of Anesthesiologists (ASA) physical status I-II aged between 18 and 65 years scheduled for elective TAPP under general anesthesia were enrolled in the study. After intubation, the patients were randomized into two groups: M: M-TAPA group (n = 30) and the control group (n = 30). M-TAPA was performed with total 40 ml 0.25% bupivacaine in the M group. Surgical infiltration was performed in the control group. The primary outcome of the study was the global quality of recovery score, the secondary outcomes were pain scores, rescue analgesic demands, and adverse effects during the 24-h postoperative period.

RESULTS

The global quality of recovery scores at 24 h were significantly higher in the M group (p < 0.001). There was a reduction in the median static and dynamic NRS for the first postoperative 8 h in the M group compared to the control group (p < 0.001). The need for rescue analgesia was significantly lower in the M group compared to the control group (13 patients vs. 24 respectively, p < 0.001). The incidence of side effects was significantly higher in the control group (p < 0.001).

CONCLUSION

In our study, M-TAPA increased patient recovery scores, and provided pain relief in patients who underwent TAPP.

REGISTER NUMBER

NCT05199922.

Clinical effects of interspace between the popliteal artery and capsule of the posterior knee block with multimodal analgesia for total knee arthroplasty: a systematic review and meta-analysis

PURPOSE

Combination of regional anaesthesia technique that is most effective in analgesia and postoperative functional outcome with the fewest complications needs investigation. Interspace between the popliteal artery and the capsule of the posterior knee block (IPACK) has been introduced clinically. We evaluated the efficacy of IPACK in combination with other nerve blocks after total knee arthroplasty.

METHODS

Data were obtained from PubMed, Cochrane Library, Web of Science, and Sciencedirect. Studies that compared outcomes using IPACK combined with other regional nerve blocks after total knee arthroplasty with other analgesic modalities and those which used pain scores or opioid consumption as primary or secondary outcomes were included.

RESULTS

Seventeen articles (20 trials, 1652 patients) were included. IPACK supplementation significantly reduced rest pain scores after total knee arthroplasty at postoperative hours 8-12(95%CI - 0.85 [- 1.36, - 0.34], I2 = 94%, p = 0.001), postoperative day 1 (95% CI - 0.49 [- 0.85, - 0.14], I2 = 87%, p = 0.006), and postoperative day 2 (95% CI - 0.28 [- 0.51, -0.05], I2 = 72%, p = 0.02); there was no significant difference at postoperative day 3 or discharge (95% CI - 0.14 [- 0.33, 0.05], I2 = 0%, p = 0.14). Combination treatment resulted in reduced dynamic pain scores at postoperative hours 8-12 (95%CI - 0.52 [- 0.92, - 0.12], I2 = 86%, p = 0.01) and postoperative day 1(95% CI - 0.49 [- 0.87, - 0.11], I2 = 88%, p = 0.01). There was no difference between postoperative day 2(95% CI - 0.29 [- 0.63, 0.05], I2 = 80%, p = 0.09), postoperative day 3 or discharge (95% CI - 0.45 [- 0.92, 0.02], I2 = 83%, p = 0.06). In addition, it strongly reduced postoperative opioid consumption within 24 H (95% CI - 0.76 [- 1.13, - 0.39], I2 = 85%, p < 0.00001), 24-48 H (95% CI - 0.43 [- 0.85, - 0.01], I2 = 83%, p = 0.04), and total opioid use (95% CI - 0.64 [- 1.07, - 0.22], I2 = 86%, p = 0.003). Although IPACK supplementation improved timed up and go test and walking distance at postoperative day 2, there was no statistically significant difference at other time periods or obvious improvement in knee range of motion and quadriceps strength. IPACK block supplementation could shorten the length of stay (LOS) (95% CI - 0.40 [- 0.64, - 0.15], I2 = 70%, p = 0.001) and improve patient satisfaction (95% CI 0.43 [0.01, 0.84], I2 = 87%, p = 0.04).

CONCLUSION

Based on these results, IPACK supplementation, in addition to standard postoperative analgesia, can be used effectively and safely to relieve early postoperative pain after total knee arthroplasty.

Comparison of analgesic efficacy of different local anesthetic volumes for erector spinae plane block in thoracotomy patients; a prospective randomized trial

BACKGROUND

Erector spinae plane block (ESPB) is a thoracic wall block that has been used frequently in recent years. It was aimed to compare the analgesic efficacy of bupivacaine in different volumes for ESPB in patients undergoing thoracotomy.

METHODS

Patients who were in the age range of 18 to 65 years, ASA I-III, had a body mass index (BMI) of 18-30 kg/m² and were undergoing thoracotomy were included in the study. Patients were assigned to ESPB with 30 ml 0.25% bupivacaine (Group-1) or ESPB with 20 ml 0.25% bupivacaine (Group-2) groups according to the analgesia protocol. In the postoperative care unit, intravenous morphine was administered via a patient-controlled analgesia pump for 24 h. A paracetamol dose of 1 g every 8 h and a dexketoprofen dose of 50 mg twice daily were administered iv for multimodal analgesia.

RESULTS

Visual analog scale (VAS) resting scores, the 1^st (p = 0.001), 2^nd (< 0.001), 4^th (< 0.001), 8^th (< 0.001), 16^th (< 0.010), 24^th (< 0.044), and 48^th (< 0.005)-hour VAS resting results were found to be statistically significantly higher in the 20 ml group than the 30 ml group. VAS cough scores were statistically significantly higher in the 20 ml group at the 1^st (< 0.003), 2^nd (< 0.001), 4^th (< 0.001), 8^th (< 0.001), 16^th (< 0.004), 24^th (< 0.031), and 48^th (< 0.009)-hour. Morphine consumption, and additional analgesic use were found to be statistically significantly higher in the 20 ml group than in the 30 ml group (p < 0.001, p = 0.001, respectively). There was no statistically significant difference between the groups in terms of side effects (p > 0.05).

CONCLUSIONS

The results of ESPB applied with 20 ml and 30 ml of local anesthetic before the surgical incision in thoracotomy patients showed that the use of 30 ml of local anesthetic provided more effective analgesia. In addition, similar side-effect rates show that 30 ml of local anesthetic can be used safely.

[Ultrasound Guided Regional Anesthesia in Thoracic Surgery]

Perioperative analgesia plays an important role in thoracic surgery, regarding not only patient satisfaction, but also in preventing postoperative complications such as pneumonia. Ultrasound-guided thoracic wall blocks close the gap between opiate based and neuraxial pain management concepts.The following article explores the different ultrasound-guided approaches to anesthetize the thoracic wall, ranging from the ventral blocks such as parasternal or PECS I/II, followed by the lateral blocks (i.e. serratus anterior), up to the dorsal approaches including the paravertebral, erector spinae plane, and retrolaminar block.In summary, the anterolateral blocks are supplementary blocks in an opiate sparing, multimodal anaesthesia concept, whereas the dorsal procedures, as they include visceral anaesthesia, are an alternative to neuraxial anaesthesia, as they have a comparable analgetic potency. For minimally invasive thoracic surgery, where due to risk-benefit considerations epidural anaesthesia is omitted, thoracic wall blocks can be utilized in a single shot or a continuous, catheter-based approach.

Ultrasound-Guided PECS II + Serratus Plane Fascial Blocks Are Associated with Reduced Opioid Consumption and Lengths of Stay for Minimally Invasive Cardiac Surgery: An Observational Retrospective Study

This study tested the hypothesis that pectoralis II (PECS II) + serratus plane blocks would reduce opioid consumption and improve outcomes compared with standard practice in minimally invasive cardiac surgery. A retrospective and observational study was realized in the intensive care unit (ICU) setting of “ICLAS GVM, Istitituto Clinico Ligure Alta Specialità, (Rapallo, Italy)”, including adult patients who underwent right minithoracotomy for replacement/plastic aortic, mitral and tricuspid valve or atrial myxoma resection in cardiac surgery. Seventy-eight patients were extracted by the database and divided into two groups. Group 1 (41 patients) received ultrasound-guided PECS II + serratus plane blocks with Ropivacaine 0.25% 10 mL + 20 mL + 30 mL. Group 2 (37 patients) received intravenous opioids analgesia with morphine 20−25 mg/day or tramadol 200−300 mg/day. The primary outcomes were: the pain perceived: Critical-Care Pain Observation Tool (CPOT) score; the opioids consumption: mg morphine or tramadol, or µg sufentanyl administered; and mg paracetamol, toradol, tramadol or morphine administered as a rescue. The secondary outcomes were the hours of orotracheal intubation and of stay in ICU, and the number of episodes of nausea, vomiting, delayed awakening and respiratory depression. Group 1 vs. Group 2 consumed less opioids (Sufentanyl p < 0.0001; Morphine p < 0.0001), had a lower pain perceived (p = 0.002 at 6 h, p = 0.0088 at 12 h, p < 0.0001 at 24 h), need for rescue analgesia (p = 0.0005), episodes of nausea and vomiting (p = 0.0237) and intubation time and ICU stay (p = 0.0147 time of IOT, p < 0.0001 stay in ICU). Ultrasound-guided PECS II + serratus plane blocks demonstrated better than intravenous opioids analgesia in patients undergoing minimally invasive cardiac surgery.

Adductor Canal Block Combined With IPACK Block for Postoperative Analgesia and Function Recovery Following Total Knee Arthroplasty: A Prospective, Double-Blind, Randomized Controlled Study

BACKGROUND

This study aimed to explore the analgesic effect among adductor canal block (ACB) combined with infiltration between the popliteal artery and the capsule of the posterior knee (IPACK) block, ACB, and IPACK block following total knee arthroplasty (TKA).

METHODS

One hundred twenty patients were randomly allocated into 3 groups including group A (ACB + IPACK block), group B (ACB), and group C (IPACK block). The primary outcome was postoperative pain score. The secondary outcome was opioid consumption. Other outcomes included functional evaluation and postoperative complications.

RESULTS

Group A showed the lowest pain scores within 8 hours at rest and with knee maximum flexion (P < .001). From 12 to 24 hours, group C showed the highest pain scores, while no significant difference was found between group A and group B. No significant difference was found among the 3 groups 24 hours postoperatively. Group C showed the most opioid consumption within the first 24 hours and during the hospitalization, while no significant difference was found between group A and group B. No significant difference was found among the 3 groups including function evaluation and postoperative complications.

CONCLUSION

ACB + IPACK block can improve early analgesia when compared with ACB. However, the small statistical benefit to the addition of IPACK block to ACB may be unlikely to be clinically significant. Further studies may focus on patient selection and how to prolong the effect of IPACK block.

Erector spinae plane block vs. peri-articular injection for pain control after arthroscopic shoulder surgery: a randomised controlled trial

Interscalene brachial plexus block is the standard regional analgesic technique for shoulder surgery. Given its adverse effects, alternative techniques have been explored. Reports suggest that the erector spinae plane block may potentially provide effective analgesia following shoulder surgery. However, its analgesic efficacy for shoulder surgery compared with placebo or local anaesthetic infiltration has never been established. We conducted a randomised controlled trial to compare the analgesic efficacy of pre-operative T2 erector spinae plane block with peri-articular infiltration at the end of surgery. Sixty-two patients undergoing arthroscopic shoulder repair were randomly assigned to receive active erector spinae plane block with saline peri-articular injection (n = 31) or active peri-articular injection with saline erector spinae plane block (n = 31) in a blinded double-dummy design. Primary outcome was resting pain score in recovery. Secondary outcomes included pain scores with movement; opioid use; patient satisfaction; adverse effects in hospital; and outcomes at 24 h and 1 month. There was no difference in pain scores in recovery, with a median difference (95%CI) of 0.6 (-1.9-3.1), p = 0.65. Median postoperative oral morphine equivalent utilisation was significantly higher in the erector spinae plane group (21 mg vs. 12 mg; p = 0.028). Itching was observed in 10% of patients who received erector spinae plane block and there was no difference in the incidence of significant nausea and vomiting. Patient satisfaction scores, and pain scores and opioid use at 24 h were similar. At 1 month, six (peri-articular injection) and eight (erector spinae plane block) patients reported persistent pain. Erector spinae plane block was not superior to peri-articular injection for arthroscopic shoulder surgery.

New peripheral nerve blocks and local anesthetics

PURPOSE OF REVIEW

To describe current developed regional blocks, their indications and clinical use. Furthermore, describe new local anesthetics recently introduced and the new agents in pipeline.

RECENT FINDINGS

There are multiple new blocks recently developed with the introduction of ultrasound to regional anesthesia and studies demonstrate effect in different surgical procedures. However, majority of the studies do not compare with gold standard and are relatively small to change clinical practice. Some of these blocks are: erector spinae plane block, infiltration between the popliteal artery and capsule of the posterior knee, pectoral nerve blocks, quadratus lumborum and transversus abdominis plane block. New local anesthetics and adjuvants have been developed in recent years. However, the studies with even with the oldest one introduced Exparel is currently questioned, large future studies are needed to determine efficacy and safety profile and compared with conventional local anesthetics.

SUMMARY

New regional block techniques and new local anesthetics have been introduced recently. However, the efficacy/safety and comparison to conventional techniques and local anesthetics are still needed. Future studies must focus on prolonging analgesia with least invasive regional technique and compare new local anesthetics with current ones.

Infiltration between the popliteal artery and the capsule of the knee (IPACK) block in knee surgery: a narrative review

BACKGROUND

The infiltration between the popliteal artery and the capsule of the knee (IPACK) block has been described as an alternative analgesic strategy for knee pain.

OBJECTIVE

Our aim was to perform a narrative review to examine the place and value that the IPACK block has in comparison to and in conjunction with other regional anesthesia modalities.

EVIDENCE REVIEW

Following an extensive search of electronic databases, we included anatomical studies, letters, comparative observational studies, and non-randomized and randomized controlled trials that examined the IPACK block in relation to surgery on the knee under general or neuraxial anesthesia.

FINDINGS

In all, 35 articles were included. Cadaveric studies demonstrated the potential for injected dye to spread to the nerves responsible for the innervation of the posterior as well as anteromedial and anterolateral aspects of the knee. Of the comparative observational studies (n=15) and non-randomized (n=1) and randomized controlled trials (n=13), 2 and 27 were conducted in the context of anterior cruciate ligament reconstruction and knee replacement surgery, respectively. The role of the IPACK block with each different permutation of regional anesthesia techniques was investigated by a small number of studies. Clinical studies, in the setting of knee replacement surgery, revealed variation in the manner in which the IPACK block was performed, and indicated the possible superiority of distal injection at the level of the femoral condyles for the management of posterior knee pain. Evidence suggested the following: the IPACK block in combination with single shot adductor canal block (ACB) may be beneficial for analgesic and functional outcomes; in conjunction with single shot or continuous ACB, the IPACK block might be superior to local infiltration analgesia (LIA); and functional outcomes may be improved with the supplementation of continuous ACB and LIA with the IPACK block. The IPACK block did not commonly result in the occurrence of foot drop. Relative to tibial nerve block (TNB), the IPACK block reduced the occurrence of foot drop and increased the proportion of patients who were able to be discharged on the third postoperative day.

CONCLUSIONS

The IPACK block was potentially complementary to the ACB and might be preferable to the TNB as a motor-sparing regional anesthesia technique in knee surgery. Definitive recommendations were not reached in the presence of the heterogeneous and limited evidence base.