Is sciatic nerve block advantageous when combined with femoral nerve block for postoperative analgesia following total knee arthroplasty? a meta-analysis

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

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

Preoperative Femoral Nerve Block and Postoperative Sciatic Nerve Block at the Subgluteal Space After Total Knee Arthroplasty: A Retrospective Cohort Study

Background A preoperative sciatic nerve block (SNB) before total knee arthroplasty (TKA) frequently causes postoperative drop foot; however, this can also occur as an unintended result of surgical invasion. This study assessed the benefits of a postoperative SNB at the subgluteal space for patients who underwent TKA. Methodology This was a single-center, retrospective cohort study. Patients who underwent TKA under general anesthesia between May 2018 and June 2019 at the Teikyo University School of Medicine were screened for inclusion. They received either a preoperative femoral nerve block alone (control group; n = 87) or a preoperative femoral nerve block and postoperative SNB at the subgluteal space (post-SNB group; n = 40). The primary outcome was the pain-related Numerical Rating Scale (NRS) scores. The secondary outcomes were postoperative nausea and vomiting (PONV), intravenous patient-controlled analgesia (iv-PCA) suspension, and postoperative complications. Results No significant differences were observed in the characteristics, NRS scores, time to first drug use for pain, and iv-PCA suspension between groups. However, the incidence of PONV was significantly lower in the post-SNB group (p = 0.03). Logistic regression analysis revealed that droperidol doses of iv-PCA and the presence of postoperative SNB were independently associated with PONV occurrence [A1] {(p = 0.008, 95% confidence intervals (CI) [0.46, 0.89] and (p = 0.02, 95% CI [0.25, 0.88])}. Conclusions A postoperative SNB at the subgluteal space following TKA does not improve postoperative pain control; however, it may have contributed to reduced PONV.

BDNF-TrkB/proBDNF-p75NTR pathway regulation by lipid emulsion rescues bupivacaine-induced central neurotoxicity in rats

Bupivacaine (BPV) can cause severe central nervous system toxicity when absorbed into the blood circulation system. Rapid intravenous administration of lipid emulsion (LE) could be used to treat local anaesthetic toxicity. This study aimed to investigate the mechanism by which the BDNF-TrkB/proBDNF-p75NTR pathway regulation by LE rescues BPV induced neurotoxicity in hippocampal neurons in rats. Seven- to nine-day-old primary cultured hippocampal neurons were randomly divided into 6 groups: the blank control group (Ctrl), the bupivacaine group (BPV), the lipid emulsion group (LE), the bupivacaine + lipid emulsion group (BPV + LE), the bupivacaine + lipid emulsion + tyrosine kinase receptor B (TrkB) inhibitor group (BPV + LE + K252a), the bupivacaine + lipid emulsion + p75 neurotrophic factor receptor (p75NTR) inhibitor group (BPV + LE + TAT-Pep5). All hippocampal neurons were incubated for 24 h, and their growth state was observed by light microscopy. The relative TrkB and p75NTR mRNA levels were detected by real-time PCR. The protein expression levels of brain-derived neurotrophic factor (BDNF), proBDNF, TrkB, p75NTR and cleaved caspase-3 were detected by western blotting. The results showed that primary hippocampal neuron activity was reduced by BPV. As administration of LE elevated hippocampal neuronal activity, morphology was also somewhat improved. The protein expression and mRNA levels of TrkB and p75NTR were decreased when BPV induced hippocampal neuronal toxicity, while the expression of BDNF was increased. At the same time, BPV increased the original generation of cleaved caspase-3 protein content by hippocampal neurons, while the content of cleaved caspase-3 protein in hippocampal neurons cotreated with LE and BPV was decreased. Thus, this study has revealed LE may reduce apoptosis and promote survival of hippocampal neurons by regulating the BDNF-TrkB pathway and the proBDNF-p75NTR pathway to rescue BPV induced central neurotoxicity in rats.

Femoral Nerve Block and Local Instillation Analgesia Associated With More Reliable Efficacy in Regional Anesthesia Interventions Within 24 Hours Following Anterior Cruciate Ligament Reconstruction: A Network Meta-analysis

PURPOSE

To assess the relative effectiveness of different regional anesthetic techniques (peripheral nerve blocks, local instillation analgesia, including intra-articular, subcutaneous, and periarticular infiltration) in patients undergoing anterior cruciate ligament reconstruction (ACLR).

METHODS

PubMed, Embase, Cochrane Library, and Web of Science databases were searched from their inception to December 31, 2020. The search was supplemented by manual review of relevant reference lists. Randomized controlled trials of participants after ACLR that compared regional anesthesia interventions were selected. The 2 coprimary outcomes were (1) rest pain scores and (2) cumulative oral morphine equivalent consumption on day 1 (24 hours) post-ACLR. Data were pooled using a Bayesian framework.

RESULTS

Of 759 records identified, 46 trials were eligible, evaluating 9 interventions in 3,171 patients. Local instillation analgesia (LIA), including intra-articular, subcutaneous, and periarticular infiltration, had significant improvement in pain relief as compared with placebo (-0.91; 95% CrI -1.45 to -0.37). Femoral nerve block (FNB) also showed significant effects in relieving pain as compared with placebo (-0.70; 95% 95% credible interval [CrI] -1.28 to -0.12). Compared with placebo, a significant reduction in opioid consumption was found in LIA (mean difference -13.29 mg; 95% CrI -21.77 to -4.91) and FNB (mean difference -13.97 mg; 95% CrI -24.71 to -3.04). Femoral and sciatic nerve block showed the greatest ranking for pain relief and opioid consumption without significant evidence (P > .05) to support superiority in comparison with placebo, respectively.

CONCLUSIONS

Our meta-analysis shows that FNB and LIA can significantly diminish postoperative pain and reduce opioid consumption following ACLR compared with placebo in the setting of regional anesthesia, and femoral and sciatic nerve block may be the number 1 top-ranked analgesic technique despite high uncertainty.

LEVEL OF EVIDENCE

I, Systematic review of Level I studies.

Efficacy and Side Effect Profile of Intrathecal Morphine versus Distal Femoral Triangle Nerve Block for Analgesia following Total Knee Arthroplasty: A Randomized Trial

(1) Background: The management of postoperative pain after knee replacement is an important clinical problem. The best results in the treatment of postoperative pain are obtained using multimodal therapy principles. Intrathecal morphine (ITM) and single-shot femoral nerve block (SSFNB) are practiced in the treatment of postoperative pain after knee replacement, with the most optimal methods still under debate. The aim of this study was to compare the analgesic efficacy with special consideration of selected side effects of both methods. (2) Materials and methods: Fifty-two consecutive patients undergoing knee arthroplasty surgery at the Department of Orthopedics and Traumatology of the Medical University of Warsaw were included in the study. Patients were randomly allocated to one of two groups. In the ITM group, 100 micrograms of intrathecal morphine were used, and in the SSFNB group, a femoral nerve block in the distal femoral triangle was used as postoperative analgesia. The other elements of anesthesia and surgery did not differ between the groups. (3) Results: The total dose of morphine administered in the postoperative period and the effectiveness of pain management did not differ significantly between the groups (cumulative median morphine dose in 24 h in the ITM group 31 mg vs. SSFNB group 29 mg). The incidence of nausea and pruritus in the postoperative period differed significantly in favor of patients treated with a femoral nerve block. (4) Conclusions: Although intrathecal administration of morphine is similarly effective in the treatment of pain after knee replacement surgery as a single femoral triangle nerve block, it is associated with a higher incidence of cumbersome side effects, primarily nausea and pruritus.

Sublingual Sufentanil Tablet System (SSTS-Zalviso®) for Postoperative Analgesia after Orthopedic Surgery: A Retrospective Study

Background: The aim of this study is to compare sublingual sufentanil and the administration device for its delivery (SSST-Zalviso®) with the traditional strategies used for the control of postoperative pain to establish if there is an actual benefit for the patient and healthcare personnel. Materials and Methods: A retrospective study was conducted to compare the efficacy of SSTS in the management of postoperative pain after orthopedic surgery between October 2018 and June 2020. We analyzed 50 patients who underwent a total knee arthroplasty (TKA). The control group consisted of 21 patients who underwent TKA and during the hospitalized recovery received a continuous femoral nerve block (cFNB). The statistical study was conducted with a level of significance p = 0.05 using “U” test, Mann−Whitney, to verify if patients had a better control of pain and fewer calls for rescue analgesia. Results: Patients involved in the study showed a significant reduction in pain intensity with the use of SSTS in the 24 h following surgery (p = 0.0568), also a drastic drop of the calls for rescue analgesia (p < 0.0001) reduces the number of calls for its control. Conclusions: This study demonstrates how SSTS might reduce pain intensity in the first 24 h after surgery and reduce the number of calls for its control, indicating better analgesic coverage and implying reduced interventions from healthcare personnel. This could allow a redistribution of resources and a reduction in the use of analgesic drugs in wards where the SSTS is used.

Pain management after total knee arthroplasty: PROcedure SPEcific Postoperative Pain ManagemenT recommendations

BACKGROUND

The PROSPECT (PROcedure SPEcific Postoperative Pain ManagemenT) Working Group is a global collaboration of surgeons and anaesthesiologists formulating procedure-specific recommendations for pain management after common operations. Total knee arthroplasty (TKA) is associated with significant postoperative pain that is difficult to treat. Nevertheless, pain control is essential for rehabilitation and to enhance recovery.

OBJECTIVE

To evaluate the available literature and develop recommendations for optimal pain management after unilateral primary TKA.

DESIGN

A narrative review based on published systematic reviews, using modified PROSPECT methodology.

DATA SOURCES

A literature search was performed in EMBASE, MEDLINE, PubMed and Cochrane Databases, between January 2014 and December 2020, for systematic reviews and meta-analyses evaluating analgesic interventions for pain management in patients undergoing TKA.

ELIGIBILITY CRITERIA

Each randomised controlled trial (RCT) included in the selected systematic reviews was critically evaluated and included only if met the PROSPECT requirements. Included studies were evaluated for clinically relevant differences in pain scores, use of nonopioid analgesics, such as paracetamol and nonsteroidal anti-inflammatory drugs and current clinical relevance.

RESULTS

A total of 151 systematic reviews were analysed, 106 RCTs met PROSPECT criteria. Paracetamol and nonsteroidal anti-inflammatory or cyclo-oxygenase-2-specific inhibitors are recommended. This should be combined with a single shot adductor canal block and peri-articular local infiltration analgesia together with a single intra-operative dose of intravenous dexamethasone. Intrathecal morphine (100 μg) may be considered in hospitalised patients only in rare situations when both adductor canal block and local infiltration analgesia are not possible. Opioids should be reserved as rescue analgesics in the postoperative period. Analgesic interventions that could not be recommended were also identified.

CONCLUSION

The present review identified an optimal analgesic regimen for unilateral primary TKA. Future studies to evaluate enhanced recovery programs and specific challenging patient groups are needed.

The effect of continuous adductor canal block combined with distal interspace between the popliteal artery and capsule of the posterior knee block for total knee arthroplasty: a randomized, double-blind, controlled trial

BACKGROUND

The optimal analgesia for total knee arthroplasty (TKA) requires excellent analgesia while preserving muscle strength. This study aimed to determine the hypothesis that continuous adductor canal block (CACB) combined with the distal interspace between the popliteal artery and the posterior capsule of the knee (IPACK) block could effectively alleviate the pain of the posterior knee, decrease opioids consumption, and promote early recovery and discharge.

METHODS

Patients undergoing unilateral, primary TKA were allocated into group CACB+SHAM (receiving CACB plus sham block) or group CACB+IPACK (receiving CACB plus IPACK block). The primary outcome was cumulative opioid consumption. Secondary outcomes included the incidence of postoperative pain originated from the posterior knee, visual analogue scale (VAS) score, range of motion, ambulation distance, and satisfaction for pain management.

RESULTS

The incidence of moderate-severe pain of the posterior knee was lower in group CACB+IPACK than that of the group CACB+SHAM at 4 hours (17.1% vs. 42.8%; p = 0.019), 8 hours (11.4% vs. 45.7%; p = 0.001), and 24 hours (11.4% vs. 34.3%; p = 0.046) after TKA. The VAS scores of the posterior knee were lower in group CACB+IPACK than that of the group CACB+SHAM at 4 hours [2 (2) vs. 3 (2-4); p = 0.000], 8 hours [1 (1, 2) vs. 3 (2-4); p = 0.001], and 24 hours [1(0-2) vs. 2 (1-4); p = 0.002] after TKA. The overall VAS scores were lower in group CACB+IPACK than that of the group CACB+SHAM at 4 hours [3 (2, 3) vs. 3 (3, 4); p = 0.013] and 8 hours [2 (2, 3) vs. 3 (2-4); p = 0.032] at rest and 4 hours [3 (3, 4) vs. 4 (4, 5); p = 0.001], 8 hours [3 (2-4) vs. 4 (3-5); p = 0.000], 24 hours [2 (2, 3) vs. 3 (2-4); p = 0.001] during active flexion after TKA. The range of motion (59.11 ± 3.90 vs. 53.83 ± 5.86; p = 0.000) and ambulation distance (44.60 ± 4.87 vs. 40.83 ± 6.65; p = 0.009) were superior in group CACB+IPACK than that of the group CACB+SHAM in postoperative day 1. The satisfaction for pain management was higher in group CACB+IPACK than that of the group CACB+SHAM [9 (8, 9) vs. 8 (7-9); p = 0.024]. There was no difference in term of cumulative opioids consumption between group CACB+IPACK and group CACB+SHAM [120(84-135) vs. 120(75-135); p = 0.835].

CONCLUSION

The combination of CACB and distal IPACK block could decrease the incidences of moderate-severe posterior knee pain, improve the postoperative pain over the first 24 hours after TKA, as well as promoting recovery of motor function. However, the opioids consumption was not decreased by adding distal IPACK to CACB.

TRIAL REGISTRATION

This study was registered at Chinese Clinical Trial Registry ( ChiCTR2200059139 ; registration date: 26/04/2022; enrollment date: 16/11/2020; http://www.chictr.org.cn ).

Buprenorphine versus dexamethasone as perineural adjuvants in femoral and adductor canal nerve blocks for total knee arthroplasty: a randomized, non-inferiority clinical trial

BACKGROUND

Optimal control of acute postoperative pain and prevention of chronic persistent pain in total knee arthroplasty (TKA) remain a challenge.

METHODS

A randomized, non-inferiority clinical trial (385 patients) evaluated every hour immediate postoperative pain during 24 h, using a verbal rating 11-point scale for patient self-reporting of pain (VRS11). All patients received subarachnoid anesthesia and were randomly allocated in 4 groups: single shots femoral (FNB) or adductor canal blocks (ACB), both with dexamethasone (dex) and buprenorphine (bup). Patients received intravenous analgesia (metamizole magnesium, dexketoprofen) and rescue analgesia when needed: intravenous (paracetamol and morphine) and/or regional (femoral and sciatic nerve blocks). Demographics and adverse effects were also recorded.

RESULTS

A 45.7% of patients had pain: bupACB 56.3%, bupFNB 50.0%, dexACB 40.6% and dexFNB 36.1% (p=0.022). Rescue analgesia was needed in 37.7% of patients (p=0.128). There were statistical differences in percentage of timepoints without pain (95.0±7.9%, p=0.014) and mean VRS11 (0.18±0.3, p=0.012) but no differences in distribution of intensity periods of pain. There were no significant differences in the need of rescue analgesia excepting the use of intravenous morphine (p=0.025).

CONCLUSIONS

buprenorphine is in the present trial inferior to dexamethasone by less than the established non-inferiority limit when used as perineural adjuvant in femoral nerve or adductor canal blocks in total knee arthroplasty analgesia. So, it could be considered an alternative in patients where dexamethasone is contraindicated, such as diabetics.

Comparison of iPACK and periarticular block with adductor block alone after total knee arthroplasty: a randomized clinical trial

PURPOSE

The infiltration between the popliteal artery and the capsule of the posterior knee (iPACK) has been described to provide analgesia without loss of muscle strength and is effective in functional recovery. This study compared iPACK + ACB (adductor canal block) with PAI (periarticular infiltration) + ACB and ACB alone in terms of postoperative analgesia and functional improvement.

METHODS

This double-blinded randomized controlled trial included 105 patients undergoing unilateral total knee arthroplasty. Patients received ACB, iPACK + ACB, and PAI + ACB along with spinal anesthesia. The primary outcome was the area under the curve (AUC) numeric rating scale (NRS) at 48 h. Secondary outcomes were cumulative postoperative analgesic consumption within 48 h, timed up-and-go test, range of motion, length of hospital stay, patient satisfaction, and adverse events.

RESULTS

The 48-h AUC movement NRS score in the iPACK + ACB group was significantly lower than in the PAI + ACB and ACB groups (p < 0.05). At the postoperative 48th h, the opioid consumption of the iPACK + ACB group was lower than those of the ACB and PAI + ACB groups (p < 0.001). The patients in the iPACK + ACB group had significantly shorter discharge and mobilization days than the ACB and PAI + ACB groups (p < 0.001).

CONCLUSIONS

The adding of an iPACK block to the ACB improves postoperative analgesia and reduces opioid consumption. In addition, this approach improves functional performance and reduces hospital stay.

Dexmedetomidine Combined with Femoral Nerve Block Provides Effective Analgesia Similar to Femoral Nerve Combined with Sciatic Nerve Block in Patients Undergoing Total Knee Arthroplasty: A Randomized Controlled Study

Background

Total knee arthroplasty (TKA) is a severe traumatic procedure, and femoral nerve block (FNB) combined with a sciatic nerve block (SNB) is widely used in TKA. However, injury of the sciatic nerve is clinically reported. Dexmedetomidine (DEX) could reduce stress and inflammation, as well as improve pain in TKA. This study aims to observe the analgesic impact of DEX combined with FNB in TKA.

Methods

Eighty-eight patients undergoing TKA were included and randomly divided into two groups: DF group (FNB combined with DEX 0.6μg/kg before surgery, followed by DEX 0.2–0.4μg/kg/h until articular closure) and SF group (FNB combined with SNB). Each nerve was blocked with 0.375% ropivacaine 20mL, and all patients received general anesthesia routinely. The primary endpoint was the pain visual analog scale (VAS) score during activities at postoperative 24 hours.

Results

There was no statistical difference in the pain VAS scores at any time point. The mean duration of analgesia for patients with rescue analgesic requests was comparable between the two groups: 25.4 ± 6.3 hours in the DF group vs 24.8 ± 6.4 hours in the SF group (two-sample t-test, p=0.738). The total dose of sufentanil was similar between groups (P=0.355). The maintenance dose of propofol and dose of rescue analgesics were comparable (all P>0.05). There were no statistical differences in the incidence of adverse events. However, the time to extubate in the DF group was significantly longer than those in the SF group (P<0.001).

Conclusion

DEX combined with FNB could provide effective analgesia similar to SNB combined with FNB in TKA.

Clinical Trial Registration

The trial was registered at the Chinese Clinical Trial Registry on November 17, 2019 (identifier: ChiCTR1900027552).

[Peripheral Regional Anaesthesia for Perioperative Analgesia]

Peripheral Regional Anaesthesia for Perioperative Analgesia Abstract. Peripheral regional anaesthesia is the actual gold standard of opioid-sparing perioperative analgesia and is mainly used for surgery of the shoulder, arm and leg. Well-trained anaesthesiologists are the prerequisite for the correct individual risk-benefit assessment and the performance of the nerve blocks using a combination of ultrasound guidance and peripheral nerve stimulation (dual guidance). The postoperative care of the patients requires trained staff.

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.

Adductor Canal Block Combined With iPACK (Interspace Between the Popliteal Artery and the Capsule of the Posterior Knee) Block vs Periarticular Injection for Analgesia After Total Knee Arthroplasty: A Randomized Noninferiority Trial

BACKGROUND

The combination of adductor canal block (ACB) and infiltration between the popliteal artery and the posterior capsule of the knee (iPACK) block may provide sufficient motor-sparing anterior and posterior knee analgesia after total knee arthroplasty. This study aimed to determine if ACB with iPACK block was noninferior to ACB with periarticular injection (PAI) when combined with postoperative multimodal analgesia regimen.

METHODS

Seventy-six patients were randomized to receive either ACB + iPACK block and continuous ACB (CACB) (ACB + iPACK group) or PAI and CACB (ACB + PAI group). Noninferiority was concluded for the primary outcome if the adjusted mean between-group difference in pain on movement at 12 postoperative hours was within 1.3 points on a visual analog pain scale. Pain scores, morphine consumption, functional performance, and adverse events were the secondary outcome measures assessed for superiority.

RESULTS

Adjusted mean differences, (ACB + iPACK) - (ACB + PAI), in anterior and posterior knee pain scores on movement at 12 postoperative hours were -0.66 (-1.86, 0.54) and -0.19 (-1.36, 0.99), respectively. The upper limit of 95% confident interval was lower than the prespecified noninferiority limit. The mean visual analog scale pain scores were low and no clinically significant differences between groups. However, morphine requirement at 48 postoperative hours was significantly higher (P < .05) and showed greater reduced quadriceps strength at 0 and 45 degrees on postoperative day 0 (P = .006 and .04, respectively) in the ACB + iPACK group.

CONCLUSIONS

ACB with iPACK block provides a noninferior analgesia compared with PAI when combined with CACB. However, patients who received ACB + iPACK block may require higher amounts of opioids and have worse immediate functional performance.

LEVEL OF EVIDENCE

Therapeutic level I.

Evidence-based Review of Periarticular Injections and Peripheral Nerve Blocks in Total Knee Arthroplasty

Background:

Recently, post-operative pain management after Total Knee Arthroplasty (TKA) has focused on a multimodal approach for reducing opioid requirements, promoting early rehabilitation, and expediting discharge from hospital. Regional anesthesia, in the form of Periarticular Injections (PAI) and Peripheral Nerve Blocks (PNB), has shown promise as adjunctive therapy to oral analgesics.

Objective:

To review the current literature surrounding regional anesthesia for TKA.

Discussion:

PNBs provide effective analgesia after TKA. Historically, femoral nerve blocks (FNB) have been commonly employed. FNBs, however, lead to the significant motor blockade to the quadriceps musculature, which can dampen early rehabilitation efforts and increase the risk of post-operative falls. Adductor Canal Blocks (ACB) have shown excellent results in reducing post-operative pain while minimizing motor blockade. Periarticular injections (PAI), and infiltration between the popliteal Artery and Capsule of the Knee (IPACK) have similarly helped in reducing patient discomfort after TKA and providing analgesia to the posterior capsular region of the knee.

Conclusion:

PAIs, and PNBs are important elements in many multimodal postoperative pain management protocols after TKA. Current evidence appears to suggest that a combination of an ACB supplemented by posterior capsular analgesic coverage through PAI or IPACK may provide optimal results.

Continuous Femoral Catheter for Postoperative Analgesia After Total Knee Arthroplasty

Introduction:

Postoperative pain management in the total knee replacement (TKR) represent a fundamental step for a positive outcome, allowing rapid mobilization, already on the first day. Further, continuous peripheral nerve block techniques have been reported to allow effective and safe control of acute postoperative pain, ensuring the implementation and completion of an accurate and intensive joint rehabilitation program.

Aim:

The aim of this study was to assess early mobility and compliance of patients that underwent TKR surgery using the femoral block.

Methods:

For the study, all patients that underwent TKR from 2015 to 2018 with ASA score between II-III was evaluated. Patients underwent vital parameters monitoring and were treated initially with midazolam (0.05mg / kg) e.v. combined sciatic block + femoral perineural catheter positioning using a peripheral nerve stimulation-assisted technique.

Results:

Intraoperatively, satisfactory analgesia was guaranteed in all patients, associated with a complete muscle relaxation of the affected limb. High patient compliance, associated with good control of acute postoperative pain was obtained in the first 24 hours after surgery (VAS 0- 1). The ROM outcomes were good in all rehabilitation stages, managing to reach 90 degrees bending on the seventh day with an average KSS score of 88-90. Patient satisfaction and impact on quality of life were assessed with the SF-36 showing average scores of 78.

Conclusion:

Continuous femoral nerve blocking ensures good postoperative analgesia in TKR allowing an early joint mobilization, a rapid functional recovery of the knee and increasing patient compliance during the post-operative rehabilitation program.

Motor-sparing effect of iPACK (interspace between the popliteal artery and capsule of the posterior knee) block versus tibial nerve block after total knee arthroplasty: a randomized controlled trial

Background and objective

An ultrasound-guided anesthetic technique targeting the interspace between the popliteal artery and capsule of the posterior knee (iPACK) can provide posterior knee analgesia with preserved motor function after total knee arthroplasty (TKA). This study compared the peroneal nerve motor-sparing effects of iPACK block and tibial nerve block (TNB) when combined with local infiltration analgesia (LIA) and continuous adductor canal block (CACB).

Methods

In this study, 105 patients scheduled for elective TKA were randomized to receive proximal iPACK block (iPACK1), distal iPACK block (iPACK2), or TNB, along with spinal anesthesia, modified LIA, and CACB. The primary outcome was the incidence of common peroneal nerve (CPN) motor blockade. Secondary outcomes included CPN sensory function, tibial sensorimotor function, posterior knee pain, pain score, intravenous morphine requirement, timed up-and-go test, quadriceps muscle strength, range of motion, length of hospital stay, patient satisfaction, and adverse events.

Results

The incidence of CPN motor blockade was significantly higher in the TNB group than in the iPACK1 (p=0.001) and iPACK2 (p=0.001) groups, but was not significant between the iPACK1 and iPACK2 groups (p=0.76). Tibial nerve motor function was more preserved in the iPACK1 and iPACK2 groups than in the TNB group (p<0.001 and p<0.001, respectively). Complete CPN and tibial sensorimotor blockade were not observed in the iPACK2 group. Posterior knee pain score was significantly higher in the iPACK1 group than in other groups during the 24-hour postoperative period (p=0.001).

Conclusions

Compared with TNB, iPACK1 and iPACK2 preserved CPN and tibial nerve motor function to a greater extent. However, iPACK2 did not demonstrate complete CPN and tibial nerve motor blockade while maintaining effective posterior knee pain relief.

Trial registration number

TCTR20180206002.

Slightly better pain relief but more frequently motor blockade with combined nerve block analgesia compared to continuous intraarticular analgesia after total knee arthroplasty

PURPOSE

Pain management after total knee arthroplasty (TKA) is still under debate. Continuous peripheral nerve blocks (PNB) can provide long pain relief but impair muscle function. Continuous intraarticular analgesia could result in longer pain relief than local infiltration analgesia without negative effects on muscle function. This study investigated the efficacy of pain control between PNB's and continuous intraarticular analgesia after TKA.

METHODS

A prospective randomized study on 140 patients undergoing TKA was performed. Patients received either a combination of continuous femoral nerve block, continuous sciatic nerve block and single-shot obturator nerve block (group R) or a local infiltration analgesia and a continuous intraarticular catheter with ropivacaine (group L). Primary outcome was pain measured on a numerical rating scale. Knee function, patient-reported outcome (PRO) and adverse events were assessed until 1 year after surgery.

RESULTS

Pain at rest was lower in group R on the day of surgery (mean NRS 3.0 vs. 4.2) and the morning of postoperative day 1 (mean NRS 3.4 vs. 4.4). Motor blockade longer than postoperative day 3 occurred more often in group R compared to group L (15.3% vs. 1.5%). Pain levels, PRO and satisfaction 3-month and 1-year after surgery were similar.

CONCLUSION

Continuous PNB's were slightly more effective in the first 24 h after surgery but were associated more often with motor blockade which should be avoided. It must be balanced if the small amount of better pain relief immediately after surgery justifies the risks associated with motor blockade following PNB's.

LEVEL OF EVIDENCE

I.

Peripheral nerve catheters: A critical review of the efficacy

Continuous peripheral nerve blocks are commonly used for postoperative analgesia after surgery. However, catheter failure may occur due to either primary (incorrect insertion) or secondary reasons (displacement, obstruction, disconnection). Catheter failure results in unanticipated pain, need for opioid use, and risk of readmission or delay in hospital discharge. This review aimed to assess definition and frequency of catheter failure, and discuss the alternatives to prolong duration of single-shot nerve blocks. A literature search was performed on peripheral catheters reporting failure as the main outcome measure. Thirty-three studies met the selection criteria, comprising 2711 catheters. Literature review suggests that peripheral nerve catheters have clinically significant failure rate when the assessment is performed using an objective (imaging) method. Subjective methods of assessment (without imaging) may underestimate the incidence of catheter failure.

Examining pain before and after primary total knee replacement (TKR): A retrospective chart review

OBJECTIVE

The goal of total knee replacement is to improve function and reduce knee pain. The aim of this retrospective chart review was to assess the change in pain intensity from prior to TKR to after TKR at time of discharge from hospital.

METHOD

Consecutive charts of 595 patients who were discharged from the orthopaedic inpatient setting between January 2014 and July 2014 were reviewed.

RESULTS

The mean pre-operative pain intensity score was 7/10 (n = 473), and the mean pain intensity score prior to discharge from hospital was 3/10 (n = 548). Four hundred and fifty-six patients had both a pre-operative and pre-discharge pain intensity score documented; for those patients there was a significant change in pain intensity scores from prior to surgery to prior to discharge (p < 0.001).

CONCLUSION

Pain after TKR can be a limiting factor in rehabilitation activities. This retrospective chart review examined the pain intensity scores before and after primary TKR for patients in our facility. We found a significant difference in the pain intensity from before surgery to after surgery. However, further research needs to be conducted to examine the intensity and quality of pain as well as which analgesics patients are consuming after discharge from hospital at 6 weeks and 3 months.

Epidural morphine improves postoperative analgesia in patients after total knee arthroplasty: A randomized controlled trial

BACKGROUND

Patients after total knee arthroplasty (TKA) often develop moderate to severe pain. This study compared the analgesic effect of low-dose epidural morphine vs. a comparable saline injection in patients following TKA surgery.

METHODS

This randomized, double-blinded, and placebo-controlled trial was conducted in a tertiary hospital in Beijing between July 1, 2017 and May 30, 2018. One hundred and ten patients following TKA under combined spinal-epidural anesthesia were randomized to receive either epidural morphine (2 mg diluted to 5 ml normal saline, the epidural morphine group) or placebo (5 ml normal saline, the placebo group). For all patients, single-injection femoral nerve block was performed, and a supplementary patient-controlled intravenous analgesia pump was provided. The severity of pain was assessed with the numerical rating scale (NRS, an 11-point scale where 0 = no pain and 10 = the worst pain) at 6, 12, 24, 36, and 48 hours after surgery. The primary endpoint was moderate to severe pain (NRS pain score ≥4) within 48 hours after surgery.

RESULTS

The percentage with moderate to severe pain within 48 hours was lower in the epidural morphine group than in the placebo group (58.2% [32/55] with epidural morphine vs. 76.4% [42/55] with placebo; OR 0.43, 95% CI 0.19-0.98; p = 0.042). Furthermore, the cumulative morphine consumption within 48 hours was lower (18.4±6.1 mg vs. 22.4±7.3 mg; p = 0.002) whereas the mental component summary score of 30-day quality of life was higher (63.8±2.9 vs. 61.9±4.2; p = 0.008) in the epidural morphine group than in the placebo group.

CONCLUSIONS

For patients following TKA, the addition of epidural morphine to single-injection femoral nerve block improves the quality of analgesia within 48 hours, without increasing adverse events.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03203967.

Ultrasound-guided single injection versus continuous sciatic nerve blockade on pain management and mobilisation after total knee arthroplasty (CoSinUS trial): A randomised, triple-blinded controlled trial

BACKGROUND

Combining continuous femoral nerve blockade with single injection sciatic nerve blockade is standard peripheral nerve block practice for total knee arthroplasty (TKA) during the first 24 postoperative hours.

OBJECTIVES

To assess the analgesic benefits and mobilisation capability of continuous sciatic blockade in conjunction with continuous femoral nerve blockade for 72 h after arthroplasty.

DESIGN

Randomised, triple-blinded controlled trial.

SETTING

Single-Centre, German University Hospital.

PATIENTS

In total, 50 patients receiving continuous femoral nerve blockade (5 ml h ropivacaine 0.2%) for TKA under general anaesthesia.

INTERVENTIONS

Patients were randomised to receive a sciatic nerve catheter with an initial dose of 10 ml ropivacaine 0.2% followed by either continuous double-blinded application of 5 ml h ropivacaine 0.2% (CO) or 5 ml h saline infusion (SIN).

MAIN OUTCOME

Measures primary endpoint: cumulative morphine consumption until 48 h postoperatively. Further endpoints included morphine consumption, pain scores, mobilisation, dynamometry until postoperative day 3.

RESULTS

Median [25th to 75th percentiles] cumulative morphine consumption at postoperative day 2 differed significantly between groups (CO 15 mg [11 to 25] versus SIN, 43 mg [27 to 67.5, P < 0.0001) in the 48 patients in the final analysis. Overall pain scores were comparable at rest and during stress at each time point. However, significantly higher pain scores of the popliteal fossa were observed in the SIN group. Mobilisation was comparable between groups.

CONCLUSION

This trial demonstrates the superior analgesic effects of continuous sciatic nerve block compared with a single injection in combination with continuous femoral blockade during the first 72 h after TKA. However, mobilisation capability was impaired in both groups. Improved pain control from two catheters needs to be balanced against the potential risks of impaired mobilisation and patient falls.

TRIAL REGISTRATION

DRKS - German clinical trials register (no: DRKS00010152).

Antimicrobial effect of anesthetic-eluting ultra-high molecular weight polyethylene for post-arthroplasty antibacterial prophylaxis

Despite being a relatively safe surgery, total joint replacement is often associated with two major complications-severe post-operative pain and periprosthetic joint infection. Local sustained delivery of therapeutics to the surgical site has a potential to address these complications more effectively than current clinical approaches. Given that several analgesics were shown to possess antibacterial activity, we propose here to use analgesic-loaded ultra-high molecular weight polyethylene (UHMWPE) as a delivery vehicle to provide antimicrobial effect after an arthroplasty. Three commonly used anesthetics, lidocaine, bupivacaine, and ropivacaine, were analyzed in order to reveal the drug with the highest antibacterial activity against methicillin-sensitive Staphylococcus aureus. Having shown highest antibacterial activity in the bacterial susceptibility tests, bupivacaine was chosen to be incorporated into UHMWPE to provide antibacterial properties. Bupivacaine-loaded UHMWPE possessed moderate dose-dependent antimicrobial properties, decreasing the S. aureus proliferation rate by up to 70%. Biofilm formation was also substanitally inhibited during the first 9 h of culture as quantified by bacterial counts and SEM. This proof-of-concept study is first of its kind to demonstrate that analgesic-loaded UHMWPE can be used as part of a multimodal antimicrobial therapy. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Regional and Multimodal Analgesia to Reduce Opioid Use After Total Joint Arthroplasty: A Narrative Review

BACKGROUND

Elective total joint arthroplasty may be a gateway to long-term opioid use.

QUESTIONS/PURPOSE

We sought to review the literature on multimodal and regional analgesia as a strategy to minimize perioperative opioid use and control pain in patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA).

METHODS

We conducted a narrative review to assess the state of the evidence informing opioid-sparing analgesics for THA and TKA. A PubMed search was conducted for English-language articles published before April 2018. We preferentially included well-designed randomized controlled trials, systematic reviews, and meta-analyses. Where the highest levels of evidence were not yet apparent, we evaluated retrospective and/or observational studies.

RESULTS

Multimodal analgesia emphasizing nonsteroidal anti-inflammatory agents and acetaminophen is associated with decreases in perioperative opioid use for THA and TKA. Regional analgesia, including peripheral nerve blocks and local infiltration analgesia, is also associated with decreased perioperative opioid use for THA and TKA. Emerging topics in post-arthroplasty analgesia include (1) the value of nonsteroidal anti-inflammatory drugs, (2) the use of peripheral nerve catheters and extended-release local anesthetics to prolong the duration of opioid-free analgesia, and (3) novel peripheral nerve blocks, exemplified by the IPACK (interspace between the popliteal artery and posterior capsule of the knee) block for TKA.

CONCLUSIONS

The use of multimodal analgesia with regional techniques may decrease perioperative opioid use for patients undergoing THA and TKA. These techniques should be part of a comprehensive perioperative plan to promote adequate analgesia while minimizing overall opioid exposure.

Opioid-Sparing Analgesia and Enhanced Recovery After Total Knee Arthroplasty Using Combined Triple Nerve Blocks With Local Infiltration Analgesia

BACKGROUND

Peripheral nerve block and local infiltration analgesia (LIA) have an increasing role as part of multimodal analgesia for enhanced recovery after total knee arthroplasty (TKA). We hypothesized that the combination of obturator nerve block (ONB) and tibial nerve block (TNB) would reduce pain and opioid consumption more than ONB or TNB alone when combined with continuous adductor canal block and LIA.

METHODS

Ninety patients were recruited into the study and received spinal anesthesia, LIA, and continuous adductor canal block. They were further randomized to receive either an ONB (group 1), a TNB (group 2), or both (group 3). The primary outcome was total morphine consumption over the postoperative 24 hours. The secondary outcomes included visual analog scale scores, time to first and total dosage of rescue analgesia, Timed Up and Go test, range of motion, muscle strength test, hospital stay, and patient satisfaction.

RESULTS

Eighty-nine patients completed analysis. The median total morphine consumption during the first 24 postoperative hours was 2 mg (interquartile range [IQR] 0-4) in group 3, 4 mg (IQR 2-8) in group 2, and 6 mg (IQR 6-14) in group 1 (P < .001). Posterior knee pain during the first 24 hours postoperatively was significantly lower in group 3 than in group 1 (P = .006). The ability to ambulate and quadriceps strength were significantly better in group 3 than in the other groups.

CONCLUSION

The combination of triple nerve block was superior to double nerve block in improving analgesia and functional outcomes in the immediate postoperative period after total knee arthroplasty, when combined with LIA.

Lower extremity regional anesthesia: essentials of our current understanding

The advent of ultrasound guidance has led to a renewed interest in regional anesthesia of the lower limb. In keeping with the American Society of Regional Anesthesia and Pain Medicine's ongoing commitment to provide intensive evidence-based education, this article presents a complete update of the 2005 comprehensive review on lower extremity peripheral nerve blocks. The current review article strives to (1) summarize the pertinent anatomy of the lumbar and sacral plexuses, (2) discuss the optimal approaches and techniques for lower limb regional anesthesia, (3) present evidence to guide the selection of pharmacological agents and adjuvants, (4) describe potential complications associated with lower extremity nerve blocks, and (5) identify informational gaps pertaining to outcomes, which warrant further investigation.

Sciatic nerve block or not for outpatient total knee arthroplasty? Study protocol for a randomized controlled trial

Background

The number of patients operated on for total knee arthroplasty (TKA) is growing worldwide. Outpatient surgery is defined by a length of stay (LOS) in the hospital of less than 12 h. This can be limited for TKA, with the efficient management of pain and perioperative complications, such as blood loss, affecting a safe hospital discharge. Outpatient TKA with a suitable protocol, including multimodal measures, could improve the success rate of this procedure. Among the main measures, single-shot sciatic nerve block in association with continuous femoral nerve block for pain control needs to be evaluated in outpatient TKA. Furthermore, to promote the safety of the postoperative period and to accelerate rehabilitation, patients who undergo ambulatory TKA could be discharged to a rehabilitation center on the day of surgery to screen adverse events and to optimize the rehabilitation process. This study is designed to assess the benefits of sciatic nerve block in postoperative pain relief for outpatient TKA.

Methods/design

This randomized prospective controlled study will be conducted in the knee unit of the teaching hospital of the Nice university and will include 40 patients undergoing primary unilateral outpatient TKA, discharged the day of surgery to a private rehabilitation center for enhanced recovery after surgery, after a hospital stay of less than 12 h. Before surgery, all patients will receive a continuous femoral nerve block with 2 mg/ml ropivacaine 20 ml, and then patients will be randomly assigned to receive or not receive a single-shot sciatic nerve block with 2 mg/ml ropivacaine, 20 ml. The primary outcome measure is the success rate of outpatient TKA. This rate is defined by patients discharged from the hospital to a rehabilitation center the day of surgery with no re-hospitalization due to insufficient pain control before the fifth postoperative day. Secondary outcomes include the incidence of major and minor adverse events during the first five postoperative days and measurement of the quality of recovery using the Knee injury and Osteoarthritis Outcome Score and the new International Knee Society scores plus the Quality of Recovery-40 questionnaire.

Discussion

The assessment of anesthesia and rehabilitation protocols enabling major orthopedic surgery, such as TKA, is necessary. This randomized controlled study will address the hypothesis that a suitable multimodal protocol including sciatic nerve block could improve pain control and thus improve the success rate of outpatient TKA.

Trial registration

EudraCT, 2016-000226-19. Registered on 15 April 2016.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3142-1) contains supplementary material, which is available to authorized users.

Lipid emulsion in local anesthetic toxicity

PURPOSE OF REVIEW

Enthusiasm for regional anesthesia has been driven by multimodal benefits to patient outcomes. Despite widespread awareness and improved techniques (including the increasing use of ultrasound guidance for block placement), intravascular sequestration and the attendant risk of local anesthetic systemic toxicity (LAST) remains. Intravenous lipid emulsion (ILE) for the treatment of LAST has been endorsed by anesthetic regulatory societies on the basis of animal study and human case report data. The accumulated mass of reporting now permits objective interrogation of published literature.

RECENT FINDINGS

Although incompletely elucidated the mechanism of action for ILE in LAST seemingly involves beneficial effects on initial drug distribution (i.e., pharmacokinetic effects) and positive cardiotonic and vasoactive effects (i.e., pharmacokinetic effects) acting in concert. Recent systematic review by collaborating international toxicologic societies have provided reserved endorsement for ILE in bupivacaine-induced toxicity, weak support for ILE use in toxicity from other local anesthetics, and largely neutral recommendation for all other drug poisonings. Work since publication of these recommendations has concluded that there is a positive effect on survival for ILE when animal models of LAST are meta-analyzed and evidence of a positive pharmacokinetic effect for lipid in human models of LAST.

SUMMARY

Lipid emulsion remains first-line therapy (in conjunction with standard resuscitative measures) in LAST. Increasing conjecture as to the clinical efficacy of ILE in LAST, however, calls for high-quality human data to refine clinical recommendations.

Oral prolonged-release oxycodone/naloxone offers equivalent analgesia to intravenous morphine patient-controlled analgesia after total knee replacement. A randomized controlled trial

BACKGROUND

The purpose of this study was to determine whether oral prolonged-release oxycodone-naloxone combination (OXN) could provide equivalent analgesia and a side-effect profile similar to intravenous morphine patient-controlled analgesia (IVPCA) for the control of pain in the immediate postoperative period after total knee replacement (TKR).

METHODS

All patients received a sciatic nerve block with 0.3% ropivacaine 15 mL, femoral nerve block with 0.5% ropivacaine 20 mL, spinal anesthesia and postoperative continuous femoral nerve infusion (ropivacaine 0.2% 4 mL/h). After surgery, patients were randomly allocated to receive either 10 +10 +5 mg controlled release OXN oral administration 12 hourly or IVPCA with morphine (2 mg bolus, no basal infusion). The primary outcome was the average rest and dynamic pain for the first 48 h postoperatively. Secondary outcomes were: post operative nausea vomiting (PONV) and the total morphine consumption.

RESULTS

OXN group experienced better pain control at rest during the first (0.89±1.54 vs. 1.27±1.82, P=0.0019) and second (1.03±1.69 vs. 1.65±2.05, P=0.0006) postoperative period. There was no statistically significant difference in pain score during movement between the two groups. The secondary outcome measures showed no significant differences in the total morphine consumption (12.04±1.1 vs. 11.46±3.7 mg, P=0.20) or PONV (0.6±0.8 vs. 0.8±1.0, P=0.40).

CONCLUSIONS

This study show that in the immediate postoperative period after TKR, the patients receiving oral prolonged-release OXN experienced the same to better pain control than those receiving morphine IVPCA, with a similar degree of PONV.

Does Combination Therapy of Popliteal Sciatic Nerve Block and Adductor Canal Block Effectively Control Early Postoperative Pain after Total Knee Arthroplasty?

Purpose

We compared adductor canal block (ACB) alone and a combination of ACB and sciatic nerve block (SNB) to control early postoperative pain after total knee arthroplasty.

Materials and Methods

One hundred patients received continuous ACB alone (group A), and another 100 patients received continuous ACB and single popliteal SNB (group B). Pain was evaluated at rest and 45° knee flexion using the numeric rating scale (NRS). The number of times the patient pressed the intravenous patient-controlled analgesia (PCA) button, total PCA volume infused, and the total dosage of additional analgesics were evaluated. We also investigated complications associated with each pain control technique.

Results

The NRS score on postoperative day 1 was significantly lower in group B than in group A. The number of times patients pressed the PCA button on postoperative day 1 and the total infused volume were significantly lower in group B than in group A. Thirty-five (35%) patients in group B developed foot drop immediately after surgery; but they all fully recovered on postoperative day 1.

Conclusions

SNB can be effective for management of early postoperative pain that persists even after ACB. Further research is needed to determine the proper dosage and technique for reducing the incidence of foot drop.

Continuous femoral nerve blockade and single-shot sciatic nerve block promotes better analgesia and lower bleeding for total knee arthroplasty compared to intrathecal morphine: a randomized trial

Background

Knee arthroplasty leads to postoperative pain. This study compares analgesia and postoperative bleeding achieved by intrathecal morphine with a continuous femoral plus single-shot sciatic nerve block.

Methods

A randomized non-blinded clinical trial enrolled patients aged over 18 years old, ASA I to III who underwent total knee arthroplasty. All patients underwent spinal anesthesia with isobaric bupivacaine, 20 mg. One group received 100 mcg of intrathecal morphine (M group), and the other received a femoral nerve block by continuous infusion plus a "single shot" block of the sciatic nerve at the end of the surgery (FI group). Pain score from verbal numeric rating scale (VNRS) and morphine consumption during the first 72 h, as well as motor blockade, adverse effects, and postoperative bleeding were recorded. Analysis of variance of repeated measures with Bonferroni post-test, t-test and Fisher exact test were used for statistical analysis.

Results

Thirty nine patients completed the study (M = 20; FI = 19 patients) and were similar except for higher age in the FI group. Motor blockade as well as movement pain during postanesthesia care unit (PACU) staying were not different between the groups, but movement pain was significantly lower in FI group after 24 h. Postoperative bleeding (ml) was lower in FI group.

Conclusions

Continuous femoral nerve block combined with sciatic nerve block provides effective for postoperative analgesia in patients undergoing total knee arthroplasty, with lower pain scores after 24 h and a lower incidence of adverse effects and bleeding compared to intrathecal morphine.

Trial registration

Retrospectively registered on https://clinicaltrials.gov/ under identifier NCT02882152, 23^rd December, 2016.

Femoral versus Multiple Nerve Blocks for Analgesia after Total Knee Arthroplasty

BACKGROUND

The PROSPECT (Procedure-Specific Postoperative Pain Management) Group recommended a single injection femoral nerve block in 2008 as a guideline for analgesia after total knee arthroplasty. Other authors have recommended the addition of sciatic and obturator nerve blocks. The lateral femoral cutaneous nerve is also involved in pain syndrome following total knee arthroplasty. We hypothesized that preoperative blocking of all four nerves would offer superior analgesia to femoral nerve block alone.

METHODS

This is a prospective, randomized, controlled, and observer-blinded clinical study. A total of 107 patients were randomly assigned to one of three groups: a femoral nerve block group, a multiple nerve block group, and a control group. All patients were treated postoperatively using patient-controlled intravenous analgesia with morphine. Pain intensity at rest, during flexion and extension, and morphine consumption were compared between groups over three days.

RESULTS

A total of 90 patients completed the study protocol. Patients who received multiple nerve blocks experienced superior analgesia and had reduced morphine consumption during the postoperative period compared to the other two groups. Pain intensity during flexion was significantly lower in the "blocks" groups versus the control group. Morphine consumption was significantly higher in the control group.

CONCLUSIONS

Pain relief after total knee arthroplasty immediately after surgery and on the first postoperative day was significantly superior in patients who received multiple blocks preoperatively, with morphine consumption significantly lower during this period. A preoperative femoral nerve block alone produced partial and insufficient analgesia immediately after surgery and on the first postoperative day. (Clinical trial registration number (NIH): NCT01303120).

Novel Regional Techniques for Total Knee Arthroplasty Promote Reduced Hospital Length of Stay: An Analysis of 106 Patients

BACKGROUND

Novel regional techniques, including the adductor canal block (ACB) and the local anesthetic infiltration between the popliteal artery and capsule of the knee (IPACK) block, provide an alternative approach for controlling pain following total knee arthroplasty (TKA). This study compared 3 regional techniques (femoral nerve catheter [FNC] block alone, FNC block with IPACK, and ACB with IPACK) on pain scores, opioid consumption, performance during physical therapy, and hospital length of stay in patients undergoing TKA.

METHODS

All patients had a continuous perineural infusion, either FNC block or ACB. Patients in the IPACK block groups also received a single injection 30-mL IPACK block of 0.25% ropivacaine. Pain scores and opioid consumption were recorded at postanesthesia care unit discharge and again at 8-hour intervals for 48 hours. Physical therapy performance was measured on postoperative days (POD) 1 and 2, and hospital length of stay was recorded.

RESULTS

We found no significant differences in the 3 groups with regard to baseline patient demographics. Although we observed no differences in pain scores between the 3 groups, opioid consumption was significantly reduced in the FNC with IPACK group. Physical therapy performance was significantly better on POD 1 in the ACB with IPACK group compared to the other 2 groups. Hospital length of stay was significantly shorter in the ACB with IPACK group.

CONCLUSION

This study demonstrated that an IPACK block reduced opioid consumption by providing effective supplemental analgesia following TKA compared to the FNC-only technique. ACB with IPACK provided equivalent analgesia and improved physical therapy performance, allowing earlier hospital discharge.