Comparison of the Effects of Adductor Canal and Femoral Nerve Blocks on Postoperative Opioid Consumption and Inflammatory Factor Levels in Elderly Patients After Total Knee Arthroplasty: A Prospective Observational Study.

Purpose: Total Knee Arthroplasty (TKA) is a highly invasive procedure causing severe postoperative pain, which hampers early mobility. Effective pain management is crucial for optimal recovery. This study aimed to evaluate how adductor canal block (ACB) and femoral nerve block (FNB) affect opioid use and inflammation factor levels in elderly TKA patients. Methods: This prospective observational study included 120 patients who received TKA, and divided them into three groups, based on the different nerve block technique: ACB, FNB, and no intervention before general anesthesia (CON). Postoperative opioid consumption, pain assessment, inflammation factor, knee function recovery and other clinical indicators were recorded. Results: The CON group had significantly higher cumulative sufentanil consumption compared to the ACB and FNB groups at both 12 h and 48h postoperative (P<0.001). Compared with the CON group, the ACB and FNB groups persistently had lower pain scores until 12 h at rest and 24 h during motion after surgery. The ACB group showed significantly lower serum concentrations of C-reactive protein (CRP) and interleukin-6 (IL-6) compared to the CON group at 24 h postoperative (P=0.017, P=0.009), and IL-6 levels remained significantly lower at 72 h postoperative (P=0.005). Both ACB and FNB groups achieved earlier ambulation compared to the CON group (P=0.002). On the first day postoperative, both the ACB and FNB groups showed significantly better knee motion (P<0.001), quadriceps strength (P<0.001), and daily mobilization (P<0.001) compared to the CON group. Additionally, the ACB group exhibited superior quadriceps strength (P<0.001) and daily mobilization (P<0.001) compared to the FNB group. Conclusion: The ACB and FNB groups exhibited comparable clinical efficacy outcomes in terms of pain scores and opioid consumption. However, the ACB group experienced reduced postoperative inflammation and improved knee recovery, especially in quadriceps strength.

Acute Pain Management in a Multi-site Trauma Patient.

Pain management is often difficult in the setting of multi-site trauma such as that caused by motor vehicle accidents (MVA), which is especially compounded in the setting of polysubstance abuse. This often results in patients with poor pain tolerance requiring escalating doses of opioid therapy, which creates a vicious cycle. The use of peripheral nerve blocks (PNB) has been shown to decrease overall opioid consumption and can be used effectively to manage postoperative pain in this patient population. Our case report aims to highlight the importance of PNBs as part of a multimodal approach to pain management in patients with polytrauma in the setting of polysubstance abuse.

Anaesthesia Considerations in a Case of Alkaptonuria Posted for Total Knee Arthroplasty.

Alkaptonuria is a rare hereditary condition in which homogentisic acid is deposited in collagenous tissues, leading to blackish discoloration, degenerative changes, restricted mobility, and pain in the affected part. The skeletal system is commonly affected, resulting in the stiffening of the vertebral spine, shoulders, knees, hip joints, and thoracic cage. Additionally, the degenerative process involves heart valves, endocardium, and kidneys, with associated pathophysiological changes. These patients present significant challenges in neuraxial anesthesia, airway management, and postoperative pain relief. In this report, we present the anesthetic management of a case of alkaptonuria undergoing total knee arthroplasty and discuss the encountered difficulties. We conclude that the perioperative anesthesia management of alkaptonuria patients requires thorough planning to effectively address the various challenges associated with the administration of anesthesia.

Efficacy of adding infiltration between the popliteal artery and the capsule of the posterior knee (IPACK) to adductor canal block and local infiltration analgesia in total knee arthroplasty: A retrospective cohort study.

OBJECTIVE: Local infiltration analgesia (LIA), adductor canal block (ACB), and infiltration between the popliteal artery and the capsule of the posterior knee (IPACK) are popular multimodal analgesia techniques used during total knee arthroplasty (TKA). This study aimed to explore the efficacy of adding the IPACK technique to ACB and LIA in patients undergoing TKA. METHODS: In this retrospective cohort study, patients who underwent primary unilateral TKA were divided into two groups based on their date of admission. Sixty-three patients underwent IPACK, ACB and LIA (IPACK group) during surgery, while 60 patients underwent ACB and LIA (control group). The primary outcome was the postoperative administration of morphine hydrochloride as a rescue analgesic. Secondary outcomes included time to first rescue analgesia, postoperative pain assessed using the visual analog scale (VAS), functional recovery assessed by knee range of motion and ambulation distance, time until hospital discharge, and complication rates. RESULTS: The two groups were similar in average postoperative 0-to-24-h morphine consumption (11.8 mg for the control group vs 12.7 mg for the IPACK group, p = .428) and average total morphine consumption (18.2 mg vs 18.0 mg, p = .983) during hospitalization. There were also no significant differences in the secondary outcomes. CONCLUSIONS: The addition of IPACK to ACB and LIA did not provide any clinical analgesic benefits. Orthopedic surgeons and anesthesiologists are justified in using ACB and LIA without IPACK for TKA.

A direct saphenous nerve block in TKA: A surgeon friendly technique! Cadaveric study.

Introduction: Effective management of postoperative pain in total knee arthroplasty (TKA) poses a significant challenge for surgeons. Achieving rapid recovery without pain and promoting early ambulation in immediate and early postoperative periods are essential for patient satisfaction. There are many pain management protocols including nerve blocks. Nerve blocks procedures were done using USG and anaesthetist dependent. This cadaveric study aimed to define the VMO (Vastus medialis obliquus) triangle to target the 'safe zone' of the saphenous nerve during TKA: A surgeon's friendly technique. Methods: 12 formalin-fixed embalmed cadaveric lower limbs were dissected to explore anatomy, trajectory, the relation of saphenous nerve and measured the distances from the nearby palpable bony landmarks. Results: The average distance to target the saphenous nerve i.e target point from midpoint of superior pole of the patella was 10.6cm, the average angle to target the saphenous nerve is the angle between the line joining the medial epicondyle to the midpoint of the superior pole of the patella is found to be 64.2°. The average distance from midpoint of superior pole patella to medial epicondyle is found to be 8.1cm. Therefore, triangle so formed using these three points (1. Medial epicondyle, 2. The midpoint of superior pole of the patella, 3. Target point of the saphenous nerve) is called a VMO triangle. Conclusions: The saphenous nerve course, relations, and the distances from intraoperative bony landmarks for the VMO triangle during TKA which is a reproducible triangle so may be useful for arthroplasty surgeons to achieve successful saphenous nerve block and to avoid related complications during total knee arthroplasty (TKA).

[Comparison of the effects of sciatic nerve block combined with continuted femoral nerve block or continuted adductor canal block on pain and motor function after total knee arthroplasty].

Objective: To compare the effect of sciatic nerve block (SNB) combined with continuted femoral nerve block (FNB) or continuted adductor canal block (ACB) on pain and motor function after total knee arthroplasty (TKA). Methods: A total of 60 patients with TKA-treated osteoarthritis of the knee who met the selection criteria were enrolled between November 2020 and February 2021 and randomised allocated into the study group (SNB combined with continuted ACB) and the control group (SNB combined with continuted FNB), with 30 cases in each group. There was no significant difference in gender, age, body mass, height, body mass index, preoperative Hospital for Special Surgery (HSS) score, femoral tibial angle, and medial proximal tibial angle between the two groups ( P>0.05). The operation time, the initial time to the ground, the initial walking distance, and the postoperative hospital stay were recorded. At 2, 4, 6, 12, 24, and 48 hours after operation, the numerical rating scale (NRS) score was used to evaluate the rest pain around the knee joint, the quadriceps femoris muscle strength was evaluated by the freehand muscle strength method, and the knee flexion and extension angles were measured. Results: There was no significant difference in the operation time and initial walking distance between the two groups ( P>0.05); the initial time to the ground and postoperative hospital stay of the study group were significantly shorter than those of the control group ( P<0.05). Except for the 48-hour postoperative NRS score of the study group, which was significantly lower than that of the control group ( P<0.05), there was no significant difference in the NRS scores between the two groups at the remaining time points ( P>0.05). The quadriceps femoris muscle strength from 4 to 24 hours postoperatively and the knee extension angle from 2 to 6 hours postoperatively of the study group were significantly better than those of the control group ( P<0.05); the differences in the quadriceps femoris muscle strength and knee extension and flexion angles between the two groups at the remaining time points were not significant ( P>0.05). Conclusion: SNB combined with either continuted ACB or continuted FNB can effectively relieve pain in patients after TKA, and compared with combined continuted FNB, combined continuted ACB has less effect on quadriceps femoris muscle strength, and patients have better recovery of knee flexion and extension mobility.

Comparison of genicular nerve block with adductor canal block for postoperative pain management in patients undergoing arthroscopic knee ligament reconstruction: A randomised controlled trial.

Background and Aims: Genicular nerve block (GNB) is beneficial in early ambulation and faster patient discharge since it selectively blocks articular branches and is motor-sparing. This study aimed to compare the analgesic efficacy of ultrasound (US)-guided GNB with adductor canal block (ACB) in patients undergoing arthroscopic anterior cruciate ligament reconstruction (ACLR). Methods: This randomised, double-blind study was conducted on 38 adults undergoing arthroscopic ACLR. Patients in Group GNB (n = 19) received US-guided GNB with 3 ml of 0.25% bupivacaine and 2 mg dexamethasone. Patients in Group ACB (n = 19) received US-guided ACB with 20 ml of 0.25% bupivacaine with 6 mg dexamethasone. Postoperative rescue analgesia was provided by intravenous Patient Controlled Analgesia (PCA) with morphine. The primary outcome was Numerical Rating Scale (NRS) pain scores over 24 h. The secondary outcome was the duration of analgesia and 24-h morphine consumption. The Chi-square test was used to test the statistical significance between categorical variables. Independent t-test or Mann-Whitney U test was used to compare continuous variables. Results: NRS scores at rest and physical activity at 24 h were similar in both the groups (P = 0.429 and P = 0.101, respectively). The mean time to rescue analgesia was comparable in both groups (Group GNB: 820.79 [483.65] min [95% confidence interval {CI}: 603.31-1038.27] and Group ACB: 858.95 [460.06] min [95% CI: 652.08, 1065.82], P = 0.805), and the mean 24-h morphine consumption was also comparable in both groups (P = 1.000). Conclusion: US-guided GNB has an analgesic efficacy similar to US-guided ACB for patients undergoing arthroscopic ACLR.

Adductor Canal Block Versus Local Infiltration Analgesia for Postoperative Pain Management in Total Knee Arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) is a common surgical procedure for patients with knee osteoarthritis, often associated with postoperative pain. Effective pain management strategies are essential for improving patient outcomes and satisfaction. This study aimed to compare the efficacy of two analgesic modalities, local infiltration analgesia (LIA) and adductor canal block (ACB), in providing postoperative pain relief for patients undergoing TKA. METHODS: This prospective randomized comparative study included 60 patients undergoing TKA for knee osteoarthritis under subarachnoid block (spinal anaesthesia). Patients were divided into two groups: LIA group (local wound infiltration with periarticular injection of bupivacaine 0.125% + dexmedetomidine 1 mcg/kg) and ACB group (ACB with bupivacaine 0.125% + 1 mcg/kg dexmedetomidine). Pain relief was assessed using the Numerical Rating Scale (NRS) score, time to first rescue analgesic requirement (NRS > 3), and total amount of analgesic needed in the first 24 hours post-surgery. RESULTS: The time to first perception of pain with NRS > 3 was 11.30±0.8 hours in the ACB group and 9.40 ± 1.1 hours in the LIA group, with a statistically significant difference (p < 0.001). Additionally, the total number of rescue analgesic doses given in the first 24 hours post-operatively differed significantly between the two groups (p = 0.046). CONCLUSION: The study concludes that ACB is an effective postoperative analgesic modality, superior to local infiltration analgesia, for patients undergoing TKA.

The Effect of Postoperative Single-Injection Adductor Canal Block in Total Knee Arthroplasty Under Spinal Anesthesia With Intraoperative Dexmedetomidine Infusion.

Background: Single-injection adductor canal block (SACB) is one of the multimodal pain managements in total knee arthroplasty. The effect of an intrathecal local anesthetic is prolonged with an intraoperative dexmedetomidine infusion. Currently, SACB's effect along with the prolonged spinal anesthesia effect by dexmedetomidine has not been studied elsewhere. Methods: Seventy-eight patients were randomized to either the SACB group (n = 39) or the control group (n = 39). Spinal anesthesia and continuous infusion of dexmedetomidine were performed intraoperatively. The SACB was performed using 15 mL of either 0.5% ropivacaine or normal saline in postanesthesia care unit postoperatively. Primary endpoint examined the average numerical rating scale (NRS) pain scores at 2, 6, 12, and 24 hours after SACB while resting or moving. The secondary outcomes were the morphine equivalent, postoperative nausea and vomiting score, quadriceps strength, and overall satisfaction score. Results: The SACB group showed a lower average NRS pain score until 24 hours than the control group (2.4 vs 3.3 resting, 3.4 vs 4.1 moving). Resting and moving NRS scores at 6 and 12 hours were significantly lower in the SACB group, whereas no difference was found at 2, 24, and 48 hours, regardless of movement. The satisfaction score was higher in the SACB group than in the control group (9 [7.3-10.0] vs 7 [5.3-8.8]), and morphine equivalent at 2 hours was lower in the SACB group (2 [1-3]) than in the control group (2.9 [1.6-4]). Conclusions: SACB provided an additional analgesic effect in patients undergoing total knee arthroplasty under spinal anesthesia with continuous dexmedetomidine intravenous infusion.

Intraoperative Surgeon-Administered Adductor Canal Block Is a Safe Alternative to Preoperative Anesthesiologist-Administered Adductor Canal Block in Primary Total Knee Arthroplasty.

BACKGROUND: The shift toward outpatient total knee arthroplasties (TKAs) has led to a demand for effective perioperative pain control methods. A surgeon-performed "low" adductor canal block ("low-ACB") technique, involving an intraoperative ACB, is gaining popularity due to its efficiency and early pain control potential. This study examined the transition from traditional preoperative anesthesiologist-performed ultrasound-guided adductor canal blocks ("high-ACB") to low-ACB, evaluating pain control, morphine consumption, first physical therapy visit gait distance, hospital length-of-stay, and complications. METHODS: There were 2,620 patients at a single institution who underwent a primary total knee arthroplasty between January 1, 2019, and December 31, 2022, and received either a low-ACB or high-ACB. Cohorts included 1,248 patients and 1,372 patients in the low-ACB and high-ACB groups, respectively. Demographics and operative times were similar. Patient characteristics and outcomes such as morphine milligram equivalents (MMEs), Visual Analog Scale pain scores, gait distance (feet), length of stay (days), and postoperative complications (30-day readmission and 30-day emergency department visit) were collected. RESULTS: The low-ACB cohort had higher pain scores over the first 24 hours (5.05 versus 4.86, P < .001) and higher MME at 6 hours (11.49 versus 8.99, P < .001), although this was not clinically significant. There was no difference in pain scores or MME at 12 or 24 hours (20.81 versus 22.07 and 44.67 versus 48.78, respectively). The low-ACB cohort showed longer gait distance at the first physical therapy visit (188.5 versus 165.1 feet, P < .001) and a shorter length of stay (0.88 versus 1.46 days, P < .01), but these were not clinically significant. There were no differences in 30-day complications. CONCLUSIONS: The low-ACB offers effective pain relief and comparable early recovery without increasing operative time or the complication rate. Low-ACB is an effective, safe, and economical alternative to high-ACB. LEVEL OF EVIDENCE: Therapeutic study, Level III (retrospective cohort study).

[A prospective comparative study on effectiveness of single versus continuous adductor canal block combined with local infiltration anesthesia in unicompartmental knee arthroplasty].

Objective: To compare the early analgesic effects and the impact on knee joint function recovery after unicompartmental knee arthroplasty (UKA) between single adductor canal block (SACB) and continuous adductor canal block (CACB) combined with local infiltration anesthesia (LIA) using a prospective study. Methods: The patients with knee osteoarthritis admitted between April 2022 and December 2023 were enrolled as a subject. Among them, 60 patients met the selection criteria and were enrolled in the study. They were randomly assigned to the SACB group or CACB group in a ratio of 1:1 using a random number table method. There was no significant difference between the two groups ( P>0.05) in terms of age, gender, height, body mass, body mass index, affected side, and preoperative resting visual analogue scale (VAS) score and active VAS score, Oxford knee score (OKS), and American Hospital of Special Surgery (HSS) score. All patients received multimodal analgesia management using LIA combined with SACB or CACB. The operation time, pain related indicators (resting and activity VAS scores, number and timing of breakthrough pain, opioid consumption), joint function related indicators (quadriceps muscle strength, knee range of motion, OKS score, and HSS score), as well as postoperative block complications and adverse events were recorded and compared between the two groups. Results: There was no significant difference in the operation time between the two groups ( P<0.05). All patients in the two groups were followed up with a follow-up time of (9.70±4.93) months in the SACB group and (12.23±5.05) months in the CACB group, and the difference was not significant ( P>0.05). The CACB group had a significant lower resting VAS score at 24 hours after operation compared to the SACB group ( P<0.05). There was no significant difference in resting and active VAS scores between the two groups at other time points ( P>0.05). The CACB group had a significantly lower incidence of breakthrough pain compared to the SACB group [9 cases (30.00%) vs. 17 cases (56.67%); P<0.05). However, there was no significant difference in the timing of breakthrough pain occurrence and opioid consumption between the two groups ( P>0.05). Four cases in the SACB group and 7 cases in the CACB group experienced adverse events, with no significant difference in the incidence of adverse events between the two groups ( P>0.05). The CACB group had significantly better knee joint mobility than the SACB group at 1 and 2 days after operation ( P<0.05). There was no significant difference between the two groups in knee joint mobility on 0 day after operation and quadriceps muscle strength and OKS and HSS scores at different time points ( P>0.05). Conclusion: In UKA, the analgesic effects and knee joint function recovery are similar when compared between LIA combined with SACB and LIA combined with CACB. However, SACB is simpler to perform and can avoid adverse events such as catheter displacement and dislocation. Therefore, SACB may be a better choice.

Does Proximal Adductor Canal Block Provide Better Analgesic Efficacy than Distal Adductor Canal Block in Patients Undergoing Knee Arthroplasty: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

To compare the analgesic efficacy and adverse events of proximal versus distal ACB for adults undergoing knee arthroplasty, we searched PubMed, Cochrane, Web of Science, and Embase to identify all eligible randomized controlled trials (RCTs). The study quality of the RCTs was evaluated using the Cochrane risk of bias assessment tool. Heterogeneity among studies was examined by Cochrane Q test. Our primary outcomes were pain intensity at rest/during movement and morphine consumption. Statistical analyses were conducted by RevMan Software. Seven eligible studies involving 400 subjects were included in this meta-analysis with 202 participants in the proximal ACB group and 198 participants in the distal ACB group. The results demonstrated that proximal ACB provided significantly better pain relief at rest at 2 h (SMD -0.27, 95% CI -0.54 to -0.01, four trials, 222 participants, I2 = 0, p = 0.04) and 24 h (SMD -0.28, 95% CI -0.48 to -0.08, seven trials, 400 participants, I2 = 0, p = 0.006) following the surgery. We found no evidence of a difference in postoperative pain intensity at other timepoints. Furthermore, we noted no evidence of a difference in cumulative morphine consumption and occurrence of adverse events. Proximal ACB provides better pain relief and comparable adverse effects profile compared with distal ACB. The analgesic benefit offered by proximal ACB, however, did not appear to extend beyond the first 24 h. The overall evidence level was mostly low or very low, which requires more well-organized multicenter randomized trials in the future.

Characterizing patient factors, perioperative interventions, and outcomes associated with inpatients falls after total knee arthroplasty.

INTRODUCTION: Mechanical falls represent a potential adverse event after total knee arthroplasty (TKA) and may introduce further injury and delay postoperative recovery. This study aimed to identify patient characteristics associated with inpatient falls, to determine the impact of inpatient falls on surgical outcomes following TKA, and to describe the relationship between tourniquet and/or adductor canal block (ACB) use and fall rates. METHODS: Patients undergoing primary, elective TKA at a single institution between 2018 and 2022 were retrospectively analyzed. Patients were stratified into groups based on whether they sustained a postoperative inpatient fall or not. Perioperative characteristics, lengths of stay (LOS), rates of 90-day readmissions, and revisions were compared, and fall characteristics were described. Subanalysis was conducted comparing fall incidence based on tourniquet and/or ACB use. RESULTS: In total 6472 patients were included with 39 (0.6%) sustaining falls. Falls most commonly occurred on postoperative days one (43.6%) and two (30.8%), and were most commonly due to loss of balance (41.9%) or buckling (35.5%). Six (15.4%) fall patients sustained minor injuries, and one (2.6%) sustained major injury (malleolar fracture requiring non-operative orthopaedic management). The LOS (3.0 ± 1.5 vs 2.3 ± 1.5 days, p = 0.002) and all-cause revision rates at latest follow-up (10.3% vs. 2.0%, p = 0.008) were significantly higher in the fall group. Falls were comparable across subgroups based on tourniquet and/or ACB use (p = 0.429). CONCLUSION: Patients who fell had a longer LOS and higher revision rate postoperatively. Rates of inpatient falls were comparable regardless of tourniquet and/or ACB use. Concern for inpatient falls should not influence surgeons when considering the use of tourniquets and/or ACBs, though well-designed, large-volume, prospective randomized studies are warranted to better understand this relationship.

Comparative Efficacy of iPACK vs Popliteal Sciatic Nerve Block for Pain Management Following Total Knee Arthroplasty: A Retrospective Analysis.

Introduction Total knee arthroplasty (TKA) is associated with severe acute postoperative pain. The use of tourniquets and drains (T/D) is common in TKA but may have an influence on postoperative pain and muscular strength. The infiltration of local anesthetic between the popliteal artery and capsule of the knee (iPACK block) is a motor-sparing block that provides analgesia to the posterior aspect of the knee. However, evidence regarding its efficacy is scarce. This study aims to assess the effectiveness of iPACK block and the impact of T/D use on pain and muscular strength after TKA. Material and methods A retrospective study was carried out including patients who underwent TKA from January 2020 to April 2023. Patients were allocated into groups according to the peripheral nerve block performed and T/D use. Results We included 415 patients in this study. No differences were found in pain at rest or the need for rescue analgesia between patients who received an iPACK block or sciatic nerve block (SNB) with T/D applied. Patients who received a SNB reported lower pain scores on movement (p = 0.019), but with a higher prevalence of motor block (p < 0.001). Patients who underwent surgery without using T/D reported lower pain scores on movement (p = 0.021) and reduced need for rescue analgesia (p = 0.041). Conclusion These findings indicate that iPACK block can facilitate early mobilization after TKA without significant impact on postoperative muscle strength. Furthermore, the use of a T/D may be a source of postoperative pain that could compromise early rehabilitation.

Analgesic effectiveness of continuous versus single-injection adductor canal block in addition to continuous popliteal sciatic nerve block for bimalleolar and trimalleolar ankle fracture surgery: Prospective randomized controlled trial.

BACKGROUND: The adductor canal block is a well-known procedure for controlling postoperative pain after medial malleolus fracture surgery. Continuous nerve block is a viable option for blocking pain for a longer period although the literature on this subject is scarce. Therefore, this study aimed to compare continuous adductor canal block (cACB) group to single-injection adductor canal block (sACB) group in those with bimalleolar or trimalleolar ankle fractures. The procedure was performed in addition to a continuous sciatic nerve block for postoperative pain relief and patient satisfaction. METHODS: The study included 57 patients who had bimalleolar or trimalleolar ankle fractures and underwent open reduction and internal fixation between August 2016 and June 2018. Each patient received a continuous sciatic nerve block and was divided into two groups: those who received cACB and those who received sACB. Each postoperative pain was scored at 4, 8, 12, 24, 48, and 72 h after surgery. Additionally, the consumption of rescue medications and patient satisfaction were evaluated. RESULTS: The two groups displayed no disparity in medial side ankle pain at 4 h and 8 h after surgery, but significantly higher pain in the sACB group at 12, 24, 48, and 72 h after surgery. However, there was no difference in the pain at the lateral side of ankle and consumption of rescue medication. In addition, the cACB group showed more satisfaction than the sACB group did. CONCLUSION: CACB is better than sACB in terms of postoperative pain control and patient satisfaction. cACB can be used for postoperative pain control in ankle fractures involving the medial malleolus. LEVEL OF EVIDENCE: Prospective Randomized Controlled Trial, Level 2.

Efficacy and safety of different bupivacaine concentrations in periarticular infiltration combined with adductor canal block for bilateral total knee arthroplasty: a randomized controlled trial.

BACKGROUND: Pain management for bilateral total knee arthroplasty (BTKA) often combines adductor canal block (ACB) with periarticular infiltration (PAI). However, concerns arise regarding local anesthetic toxicity. This study evaluated the efficacy and safety of different bupivacaine concentrations in simultaneous BTKA. METHODS: Patients undergoing simultaneous BTKA under spinal anesthesia were included in the study. They received ACB with 50 mg bupivacaine for each thigh. The patients were then randomized into two groups. Group A was administered a PAI of 100 mg bupivacaine per knee (totaling 300 mg bupivacaine for ACB and PAI). Group B received a PAI with 50 mg bupivacaine per knee (totaling 200 mg bupivacaine for ACB and PAI). Postoperative pain was assessed using a visual analog scale at 4-h intervals for 48 h after surgery. Plasma bupivacaine concentrations were measured at eight specified times. Postsurgery walking ability was also evaluated. RESULTS: Among the 57 participants analyzed, visual analog scale pain scores revealed no significant differences between the two groups. An interim analysis of plasma bupivacaine concentrations in both groups indicated no significant disparities. In group B, 93.1% managed to walk with assistance within 48 h, as opposed to group A's 71.4% (P = 0.041). CONCLUSIONS: Combining ACB with 100 mg bupivacaine and PAI with another 100 mg bupivacaine provided effective pain relief. This combination also had a better safety profile and led to more patients walking postsurgery than when combining ACB with 100 mg bupivacaine and PAI with 200 mg bupivacaine. Thus, ACB combined with PAI with a total dose of 200 mg bupivacaine appears suitable for simultaneous BTKA. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03249662).

Periarticular injection, iPACK block, and peripheral nerve block in pain management after total knee arthroplasty: a structured narrative review.

INTRODUCTION: Total knee arthroplasty (TKA) is commonly performed in patients with end-stage osteoarthritis or rheumatoid arthritis of the knee to reduce joint pain, increase mobility, and improve quality of life. However, TKA is associated with moderate to severe postoperative pain, which remains a significant clinical challenge. Surgeon-administered PAI and anesthesiologist-administered iPACK have proven viable alternatives to conventional peripheral nerve blocks. This review aims to discuss which IPACK block or periarticular injection, combined or not with different peripheral nerve blocks, has better effects on postoperative rehabilitation, patient satisfaction, and overall outcome. MATERIAL AND METHODS: The literature review was performed on standards of care, current therapeutic options, a pain management protocol, and innovative treatment options for patients undergoing total knee arthroplasty. The literature was reviewed through four electronic databases: PubMed, Cochrane Library, Google Scholar, and Embase. RESULTS: The initial search yielded 694 articles. Fifty relevant articles were selected based on relevance, recentness, search quality, and citations. Six studies compared PAI to peripheral nerve block (PNB), and eight studies checked the effectiveness of adding PNB to PAI. Three studies compared iPACK to PNB, and ten reviewed the point of adding PNB to iPACK. CONCLUSIONS: The literature review indicates that the best analgesic effect is obtained by combining PAI or iPACK with a peripheral nerve block, particularly with ACB, due to its analgesic, motor-sparing effect, and satisfactory analgesia.

Pain Management, Functional Recovery, and Stress Response Expressed by NLR and PLR after the iPACK Block Combined with Adductor Canal Block for Total Knee Arthroplasty-A Prospective, Randomised, Double-Blinded Clinical Trial.

INTRODUCTION: This study aimed to investigate pain management, functional recovery, and stress response expressed by the neutrophile-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) after the popliteal artery and posterior knee capsule infiltration (iPACK) block combined with adductor canal block (ACB) in total knee arthroplasty (TKA). PATIENTS AND METHODS: This was a prospective, double-blinded, randomised, controlled trial in a tertiary referral hospital. Three hundred and sixty-six patients were randomly allocated into the sham block group and iPACK combined with the ACB group. The primary outcome was postoperative pain scores. The secondary outcomes were opioid consumption, functional recovery expressed by a range of motion, and quadriceps strength. Also, the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were calculated. RESULTS: There were significant differences between the sham block and iPACK + ACB group in pain scores p < 0.0001 at all time points. Therefore, there was a significant difference in opioid consumption (p < 0.0001) and functional recovery (p < 0.0001). Also, NLR and PLR levels 12 h (p < 0.0001) and 24 h (24 h) after surgery (p < 0.0001) were much lower in the iPACK + ACB group. CONCLUSION: After total knee arthroplasty, the iPACK combined with ACB block group improved pain management, functional recovery, and stress response. Therefore, we strongly recommend this technique as a part of a multimodal analgesia protocol in knee surgery.

Preliminary experience on systemic effects of perineural dexamethasone sodium phosphate and methylprednisolone acetate through adductor canal block in total knee arthroplasty: A single center retrospective study.

Background and Aims: Glucocorticoids are commonly utilised as adjuvants to enhance nerve block quality and prolong the analgesic duration. Its systemic effects, after a single-injection adductor canal block (ACB) followed by a continuous infusion, are unclear. The aim of the study was to assess the systemic effects of a single dose of dexamethasone sodium phosphate (DEX), or a combination of DEX and methylprednisolone acetate (MPA), on fasting blood glucose (FBG) and white blood cell count (WBC) when administered perineurally via ACB. Material and Methods: A single-center retrospective study on total knee arthroplasty (TKA) was performed and a total of 95 patients were included in the final analysis. Patients were divided into three groups based on adjuvants received in ACB: Control group (N = 41) and two treatment groups, DEX group (N = 33) and DEX/MPA group (N = 21). Our primary outcomes were the change of FBG from its preoperative baseline value on postoperative day (POD) 2. The secondary outcomes included change of FBG on POD 0 and POD 1, and change of WBC on POD 0, POD 1, and POD 2. Results: The FBG change from baseline in the DEX group was significantly higher than that in the control group (difference = 14.04, 95% CI: 1.3 to 26.77), P = 0.031) on POD 0. The WBC change from baseline in the DEX/MPA group was statistically significant higher than control on POD 0 (2.62 (1.52 to 3.37), P < 0.0001). No significant differences between DEX and DEX/MPA group were found on any given postoperative days for FBG and WBC. Conclusion: This study provided preliminary safety data on the use of a combination of glucocorticoids with hydrophilic (DEX) and lipophilic (MPA) properties as local anesthetic adjuvants in ACB, which induced similar levels of changes on FBG and WBC as those from both control and DEX alone group.

Early versus delayed postoperative adductor canal block in total knee arthroplasty.

Background: We hypothesized that patients who received an adductor canal block (ACB) in the operating room following unilateral total knee arthroplasty would have a lower oral morphine milligram equivalent (MME) consumption during the postanesthesia care unit (PACU) phase 1 recovery period compared to patients who received an ACB in the PACU. Methods: This was a retrospective cohort study of patients who underwent robotic-assisted unilateral total knee arthroplasty under general anesthesia between March 1, 2020, and February 28, 2021, and received postoperative ACB either in the operating room or the PACU. Results: A total of 36 and 178 patients received postoperative ACB in the operating room and PACU, respectively, and had median and interquartile range MME consumption in the PACU of 22.5 (20-40) mg and 30.0 (20-40) mg (P = 0.76), respectively. Patients who had an ACB performed in the operating room and PACU had median and interquartile ranges of time spent in the PACU of 101 (75-178) minutes and 186 (125-272) minutes (P < 0.01), respectively. Conclusion: Patients who received an ACB in the operating room did not have a lower OME consumption than patients who received an ACB in the PACU but did have a shorter PACU length of stay.