Continuous Intra-articular Infusion of Ropivacaine after Unilateral Total Knee Arthroplasty

Analgesic efficacy of single-shot adductor canal block versus adductor canal block combined with intra-articular ropivacaine infusion after total knee arthroplasty

Aims

Single-shot adductor canal block (ACB) after total knee arthroplasty (TKA) for postoperative analgesia is a common modality. Patients can experience breakthrough pain when the effect of ACB wears off. Local anaesthetic infusion through an intra-articular catheter (IAC) can help manage breakthrough pain after TKA. We hypothesized that combined ACB with ropivacaine infusion through IAC is associated with better pain relief compared to ACB used alone.

Methods

This study was a prospective double-blinded placebo-controlled randomized controlled trial to compare the efficacy of combined ACB+ IAC-ropivacaine infusion (study group, n = 68) versus single-shot ACB+ intra-articular normal saline placebo (control group, n = 66) after primary TKA. The primary outcome was assessment of pain, using the visual analogue scale (VAS) recorded at 6, 12, 24, and 48 hours after surgery. Secondary outcomes included active knee ROM 48 hours after surgery and additional requirement of analgesia for breakthrough pain.

Results

The study group (mean visual analogue scale (VAS) pain score of 5.5 (SD 0.889)) experienced significant reduction in pain 12 hours after surgery compared to the control group (mean VAS 6.62 (SD 1.356); mean difference = 1.12, 95% confidence interval (CI) -1.46 to 0.67; p < 0.001), and pain scores on postoperative day (POD) 1 and POD-2 were lower in the study group compared to the control group (mean difference in VAS pain = 1.04 (-1.39 to -0.68, 95% CI, p < 0.001). Fewer patients in the study group (0 vs 3 in the control group) required additional analgesia for breakthrough pain, but this was not statistically significant. The study group had significantly increased active knee flexion (mean flexion 86.4° (SD 7.22°)), compared to the control group (mean 73.86° (SD 7.88°), mean difference = 12.54, 95% CI 9.97 to 15.1; p < 0.014).

Conclusion

Combined ACB+ ropivacaine infusion via IAC is a safe, reproducible analgesic modality after primary TKA, with superior analgesia compared to ACB alone. Further large volume trials are warranted to generate evidence on clinical significance on analgesia after TKA.

Cite this article: Bone Jt Open 2021;2(12):1082–1088.

Assessing outcome in postoperative pain trials: are we missing the point? A systematic review of pain-related outcome domains reported in studies early after total knee arthroplasty

ABSTRACT

The management of acute postoperative pain remains suboptimal. Systematic reviews and Cochrane analysis can assist with collating evidence about treatment efficacy, but the results are limited in part by heterogeneity of endpoints in clinical trials. In addition, the chosen endpoints may not be entirely clinically relevant. To investigate the endpoints assessed in perioperative pain trials, we performed a systematic literature review on outcome domains assessing effectiveness of acute pain interventions in trials after total knee arthroplasty. We followed the Cochrane recommendations for systematic reviews, searching PubMed, Cochrane, and Embase, resulting in the screening of 1590 potentially eligible studies. After final inclusion of 295 studies, we identified 11 outcome domains and 45 subdomains/descriptors with the domain "pain"/"pain intensity" most commonly assessed (98.3%), followed by "analgesic consumption" (88.8%) and "side effects" (75.3%). By contrast, "physical function" (53.5%), "satisfaction" (28.8%), and "psychological function" (11.9%) were given much less consideration. The combinations of outcome domains were inhomogeneous throughout the studies, regardless of the type of pain management investigated. In conclusion, we found that there was high variability in outcome domains and inhomogeneous combinations, as well as inconsistent subdomain descriptions and utilization in trials comparing for effectiveness of pain interventions after total knee arthroplasty. This points towards the need for harmonizing outcome domains, eg, by consenting on a core outcome set of domains which are relevant for both stakeholders and patients. Such a core outcome set should include at least 3 domains from 3 different health core areas such as pain intensity, physical function, and one psychological domain.

Adductor canal block versus periarticular infiltration for pain control following total knee arthroplasty: Study protocol for a randomized controlled trial

BACKGROUND

Periarticular infiltration (PAI) and adductor canal block (ACB) have become popular modes of pain management after total knee arthroplasty. The purpose of our study is to evaluate the efficacy of ACB in comparison with PAI for pain control in patients undergoing primary total knee arthroplasty.

METHODS

This study is a prospective, 2-arm, parallel-group, open-label randomized controlled trial that is conducted at a single university hospital in China. A total of 120 patients who meet inclusion criteria are randomized in a ratio of 1:1 to either ACB or PAI group. The primary outcome is visual analog scale score at rest 24 hours after surgery, whereas the secondary outcomes include visual analog scale score at 48 hours after surgery, satisfaction, opioid consumption, and complications. All pain scores are assessed by an independent observer who is blinded to the allocation of groups.

RESULTS

This study has limited inclusion and exclusion criteria and a well-controlled intervention. This clinical trial is expected to provide evidence of better therapy for the pain management after total knee arthroplasty.

TRIAL REGISTRATION

This study protocol was registered in Research Registry (researchregistry5410).

Randomized Prospective Comparative Study of Adductor Canal Block vs Periarticular Infiltration on Early Functional Outcome After Unilateral Total Knee Arthroplasty

BACKGROUND

Total knee arthroplasty (TKA) is associated with significant postoperative pain. Effective pain relief is essential for early postoperative rehabilitation. Periarticular infiltration (PAI) and adductor canal block (ACB) have become popular modes of pain management after TKA. Our aim is to compare their efficacy and impact on early functional outcome in patients undergoing TKA.

METHODS

A single-blinded randomized controlled trial, 100 patients undergoing unilateral primary TKA for symptomatic osteoarthritis were allocated to either of the 2 groups (50 in each arm): postoperative ultrasound-guided single shot of ACB (group A) or intraoperative PAI (group B). All patients underwent TKA without patella resurfacing under spinal anesthesia. Preoperative workup, surgical technique, and postoperative management were standardized for all the patients. Patients were assessed for pain using visual analogue scale at 6, 12, and 24 hours after surgery; hemoglobin level preoperatively and postoperatively on day 1 to calculate blood loss; hospital stay; tourniquet time; operative time; and postoperative complications by an independent observer blinded to the group allocation.

RESULTS

Patients were matched for age, gender, American Society of Anesthesiologists grade, and deformity. Visual analogue scale (scale 0-10) between PAI and ACB at 6, 12, and 24 hours were significantly different (P < .05) with higher scores seen in patients with ACB at all time points. Tourniquet time and operative time were significantly longer in the PAI than ACB. No significant difference in hospital stay was observed. No complications occurred during the study.

CONCLUSION

PAI achieves better pain control as compared to ACB in patients undergoing unilateral TKA.

Effectiveness and weakness of local infiltration analgesia in total knee arthroplasty: a systematic review

Local infiltration analgesia has been widely used for pain relief in patients undergoing total knee arthroplasty. However, the effectiveness and major weakness of this technique have not been clarified; therefore, improvements in the technique have been limited. We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials and conducted a meta-analysis of randomized controlled trials comparing local infiltration analgesia with placebo infiltration in patients undergoing total knee arthroplasty. Fourteen trials involving 1305 knees were eligible. The results showed that local infiltration analgesia significantly reduced early perioperative pain and total narcotic consumption. However, postoperative functional outcomes were not significantly different between local infiltration analgesia and placebo. The pain-relieving effect of local infiltration analgesia was found to be strong but short in duration. In the future, modified delivery methods and formulas with longer durations of action and analgesia may provide a better environment for patients and therefore improve their function outcomes.

Local anesthetic infusion pump for pain management following total knee arthroplasty: a meta-analysis

Background

We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) were to evaluate the effect and safety of local anesthetic infusion pump versus placebo for pain management following total knee arthroplasty (TKA).

Methods

In September 2016, a systematic computer-based search was conducted in the Pubmed, ISI Web of Knowledge, Embase, Cochrane Database of Systematic Reviews. Randomized controlled trials of patients prepared for primary TKA that compared local anesthetic infusion pump versus placebo for pain management following TKA were retrieved. The primary endpoint was the visual analogue scale (VAS) with rest or mobilization at 24, 48 and 72 h and morphine consumption at 24 and 48 h. The second outcomes are range of motion, length of hospital stay (LOS) and complications (infection, deep venous thrombosis (DVT), prolonged drainage and postoperative nausea and vomiting (PONV)).

Results

Seven clinical studies with 587 patients were included and for meta-analysis. Local anesthetic infusion pump are associated with less pain scores with rest or mobilization at 24 and 48 h with significant difference. However, the difference was likely no clinical significance. There were no significant difference between the LOS, the occurrence of DVT, prolonged drainage and PONV. However, local anesthetic infusion pump may be associated with more infection.

Conclusion

Based on the current meta-analysis, we found no evidence to support the routine use of local anesthetic infusion pump in the management of acute pain following TKA. More RCTs are still need to identify the pain control effects and optimal dose and speed of local anesthetic pain pump.

Combined adductor canal block with periarticular infiltration versus periarticular infiltration for analgesia after total knee arthroplasty

BACKGROUND

Both adductor canal block (ACB) and periarticular infiltration (PI) have been shown to reduce pain after total knee arthroplasty (TKA) without the motor blockade. However, the efficacy and safety of combined ACB with PI (ACB + PI) as compared to PI alone for analgesia after TKA remains controversial. We therefore performed a meta-analysis to compare the effects of ACB + PI with PI alone on pain controll after TKA.

METHODS

PubMed, Medline, Embase, Web of Science, and the Cochrane Library were searched to identify studies comparing ACB + PI with PI alone for TKA patients. The primary outcomes included pain score with rest or activity and morphine consumption. Secondary outcomes were distance walked, length of hospital stay, and postoperative complications. Relevant data were analyzed using RevMan v5.3.

RESULTS

Three studies involving 337 patients were included. Combined ACB with PI was associated with longer distances walked than PI alone (MD = 7.27, 95% CI: 0.43-14.12, P = 0.04) on postoperative day 1. The outcomes of pain, morphine consumption, length of hospital stay, and postoperative complications were not statistically different between the 2 groups (P > 0.05).

CONCLUSION

Our meta-analysis suggests that combined ACB with PI may achieve earlier ambulation for patients after TKA without a reduction in analgesia when compared to PI alone in the early postoperative period. There were no significant differences in morphine consumption, length of hospital stay, and postoperative complications between the 2 groups. However, owing to the variation of included studies, no firm conclusions can be drawn.

Continuous Local Infiltration Analgesia for Pain Control After Total Knee Arthroplasty: A Meta-analysis of Randomized Controlled Trials

A total knee arthroplasty (TKA) has always been associated with moderate to severe pain. As more research is conducted on the use of continuous local infiltration analgesia (CLIA) to manage pain after a TKA, it is necessary to reassess the efficacy and safety of the TKA method. The purpose of this systematic review and meta-analysis of randomized controlled trials was to evaluate the efficacy and safety of pain control of CLIA versus placebo after a TKA. In January 2015, a systematic computer-based search was conducted in the Medline, Embase, PubMed, CENTRAL (Cochrane Controlled Trials Register), Web of Science, Google database, and Chinese Wanfang databases. This systematic review and meta-analysis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement criteria. The primary endpoint was the visual analog scale score after a TKA with rest or mobilization at 24, 48, and 72 hours, which represents the effect of pain control after TKA. The complications of infection, nausea, and whether it prolonged wound drainage were also compiled to assess the safety of CLIA. RevMan 5.30 software was used for the meta-analysis. After testing for publication bias and heterogeneity across studies, data were aggregated for random-effects modeling when necessary. Ten studies involving 735 patients met the inclusion criteria. The meta-analysis revealed that continuous infusion analgesia provided better pain control with rest at 24 hours (mean difference [MD] -12.54, 95% confidence interval [CI] -16.63 to 8.45), and with mobilization at 24 hours (MD -18.27, 95% CI -27.52 to 9.02) and 48 hours (MD -14.19, 95% CI -21.46 to 6.93). There was no significant difference with respect to the visual analog scale score at 48 hours (MD -6.15, 95% CI -13.51 to 1.22, P = 0.10) and 72 hours (MD -3.63, 95% CI -10.43 to 3.16, P = 0.29) with rest and at 72 hours with mobilization (MD -4.25, 95% CI -16.27 to 7.77, P = 0.49). However, CLIA increased the rate of infection (relative risk [RR] 3.16, 95% CI 1.18-8.50, P = 0.02) and the rate of nausea or vomiting (RR 0.60, 95% CI 0.37-0.96, P = 0.03). There were no significant differences in the length of hospital stay (MD -0.34, 95% CI -1.09 to 0.42, P = 0.38), deep venous thrombosis (RR 1.02, 95% CI 0.30 to 1.41, P = 0.99), or duration of surgery (MD 1.20, 95% CI -4.59 to 6.98, P = 0.69). On the basis of the current meta-analysis, CLIA was more efficacious for reducing postoperative pain than the placebo at 24 hours with rest and at 24 and 48 hours with mobilization, but it increased the risk of infection. However, CLIA did not prolong the length of hospital stay or the duration of surgery. There was also a higher heterogeneity of different analgesic drugs mixed and a high risk of selection bias in this analysis; therefore, more high-quality randomized controlled trials with standardized CLIA are necessary for proper comparisons of this technique with other methods.

Systematic review of high-volume multimodal wound infiltration in total knee arthroplasty

Pain relief following total knee arthroplasty (TKA) is challenging because early mobilization and rehabilitation are essential for a successful outcome. Postoperative pain can limit recovery, leading to reduced mobility and prolonged hospitalization. There are potential benefits of infiltrating high volumes of local anesthetics around the soft tissues of replaced hip and knee joints. The risk of systemic toxicity is minimized with diluted local anesthetic solution, which also allows a high volume to be used. One of the principal advantages is that analgesia agents are administered intraoperatively by the surgeon, thereby minimizing the need for additional invasive procedures. The authors conducted a systematic review to evaluate whether high-volume multimodal wound infiltration reduces pain and opiate intake while enhancing early rehabilitation and discharge when used in patients undergoing TKA. Only randomized controlled studies were included. Although better pain relief in the immediate postoperative period with wound infiltration is gained after TKA, there is no definite evidence that this leads to a reduction in opiate consumption, the achievement of early milestones, or a reduction in hospital stay. The roles of individual agents in achieving pain relief and the use of percutaneous wound catheter for postoperative doses are also unclear. There are few reports of complications, including falls and delayed mobilization, when femoral nerve blocks are used. Wound infiltration analgesia should be used at the preference of the surgeon and anesthetist provided regular review of their practice is undertaken to identify any untoward side effects. Further randomized trials with sufficient sample size comparing each outcome, including pain scores, opiate consumption, and length of hospital stay, should be undertaken.

Postoperative pain control by intra-articular local anesthesia versus femoral nerve block following total knee arthroplasty: impact on discharge

INTRODUCTION

The goal of this retrospective study was to compare pain control following total knee arthroplasty (TKA) on a perioperative protocol of local anesthesia (LA) versus the more classical femoral nerve block (FNB) technique.

HYPOTHESIS

Fitness for discharge would be achieved earlier using the LA protocol.

MATERIALS

Ninety-eight consecutive TKA patients operated on by a single surgeon were included with no selection criteria. In the study group (49 patients), 200 mL ropivacaine 5% was injected into the surgical wound and an intra-articular catheter was fitted to provide continuous infusion of 20 mL/h ropivacaine for 24h. The control group (49 patients) received ropivacaine FNB. Discharge fitness (independent walking, knee flexion>90°, quadricipital control, pain on VAS≤3) and hospital stay were assessed.

RESULTS

Discharge fitness was achieved significantly earlier in the study group (4.2±2.6 versus 6.7±3.2 days; P=0.0003), with significantly shorter mean hospital stay (6.1±3.4 versus 8.8±3.5 days; P=0.0002). The complications rate did not differ between study and control groups.

DISCUSSION

Although retrospective, this study indicates that the LA protocol improves management of post-TKA pain and accelerates rehabilitation, thereby, reducing hospital stay. The acceleration effect may be due to the absence of quadriceps inhibition.

LEVEL OF EVIDENCE

Level III - Case control study.

Continuous infusion of bupivacaine following total knee arthroplasty: a randomized control trial pilot study

An RCT pilot-study was conducted to assess efficacy of a 48-h continuous local infiltration of intra-articular bupivacaine (0.5% at 2 cc/h) versus placebo (0.5% saline at 2 cc/h) in decreasing PCA morphine consumption following TKA. Secondary outcomes included 48-h VAS pain, opioid side effects, length of stay, and knee function scores up to 1-year postoperatively. Of 67 randomized patients, 49 completed the trial including 24 bupivacaine, and 25 placebo patients. Mean 48-h PCA morphine consumption did not differ significantly between treatment (39 mg ± 27.1) and placebo groups (53 mg ± 30.4) (P = .137). The intervention did not improve pain scores, or any other outcome studied. Given study results we would conclude that analgesia outcomes with a multimodal analgesia regimen are not significantly improved by adding 48 h of 0.5% bupivacaine infiltration at 2 cc/h.

Effect of Single-Injection versus Continuous Local Infiltration Analgesia after Total Knee Arthroplasty: A Randomized, Double-Blind, Placebo-Controlled Study

In this randomized, double-blind, placebo-controlled, single-centre study, 80 patients (American Society of Anesthesiologists physical status I — III) received postoperative single-injection local infiltration analgesia (SLIA), continuous local infiltration analgesia (CLIA) or placebo (control group). Intravenous patient-controlled morphine was used as rescue analgesia. The CLIA group showed lower postoperative visual analogue scale (VAS) pain scores from 8 to 48 h at rest and from 16 to 48 h during activity compared with the SLIA group. The CLIA group also had significantly lower consumption of morphine from 24 to 48 h postoperatively versus the SLIA group. Patient satisfaction was higher, and maximum flexion of the knee on postoperative days 7 and 90 was greater, in the CLIA group compared with the SLIA group. CLIA provided prolonged superior analgesia and was associated with more favourable functional recovery and patient satisfaction compared with SLIA.

Pain control infusion pumps: a prospective randomized evaluation in bilateral total knee arthroplasty

We prospectively monitored pain scores on 24 patients who underwent bilateral total knee arthroplasty (TKA). Patients were blinded to receiving either a functional or placebo pain control infusion pumps. After 3 days, pump volume was recorded, and patients were asked to identify which knee they believed received the functional pain control infusion pump. Fourteen patients (58%) correctly identified their knee with the functional pain control infusion pump. Pump volumes ranged from 70 to 310 mL, with an average flow rate of 4.3 mL/hour. Positive identification rates were similar to rates routinely generated from standard placebo symptom treatment pain trials (0%-60%). Our data suggest that the placebo effect plays at least a partial role in pain control infusion pump effectiveness, and that pain control infusion pump use for TKA unpredictably contributes to postoperative pain management. [corrected]

Reduced opioid consumption and improved early rehabilitation with local and intraarticular cocktail analgesic injection in total hip arthroplasty: a randomized controlled clinical trial

OBJECTIVE

Postoperative pain after total hip arthroplasty (THA) is not well tolerated. We assessed postoperative pain relief and the need for opioid use after using a cocktail of local and intraarticular analgesic injection (LIA) after THA.

METHODS

Eighty patients undergoing THA under spinal anesthesia were randomly assigned to receive either LIA or placebo. The LIA was composed of 5 mg morphine, 30 mg bupivacaine (15 mg/1.5 mL), 1 mL betamethasone, and 0.5 mL epinephrine (1:1,000) intraoperatively. We compared three outcomes total morphine consumption, visual analog scale (VAS) at rest and during activity, and hip flexion angle while standing.

RESULTS

When compared with placebo, opioid consumption was significantly reduced in the trial group, as well as VAS at rest and during mobilization. Earlier rehabilitation and better range of motion (ROM) were achieved in the trial group. There were no significant differences in side effects or postoperative wound healing between groups.

CONCLUSION

In patients undergoing THA, LIA may reduce postoperative systemic opioid use and offer better pain control and earlier rehabilitation, without observable risks.

Use of invasive placebos in research on local anaesthetic interventions

Placebos play a vital role in clinical research, but their invasive use in the context of local anaesthetic blocks is controversial. We assessed whether recently published randomised controlled trials of local anaesthetic blocks risked harming control group patients in contravention of the Declaration of Helsinki. We developed the 'SHAM' (Serious Harm and Morbidity) scale to assess risk: grade 0 = no risk (no intervention); grade 1 = minimal risk (for example, skin allergy to dressing); grade 2 = minor risk (for example, subcutaneous haematoma, infection); grade 3 = moderate risk (with or without placebo injection) (for example, neuropraxia); and grade 4 = major risk (such as blindness, pneumothorax, or liver laceration). Placebo interventions of the 59 included trials were given a SHAM grade. Nine hundred and nineteen patients in 31 studies, including six studies with 183 children, received an invasive placebo assessed as SHAM grade ≥ 3. A high level of agreement (78%, κ = 0.80, p < 0.001) for SHAM grades 0-4 increased to 100% following discussion between assessors. More than half of the randomised controlled study designs subjected patients in control groups to risks of serious or irreversible harm. A debate on whether it is justifiable to expose control group patients to risks of serious harm is overdue.

Continuous peripheral nerve blocks in acute pain management

The indications for continuous nerve blocks for the perioperative pain management in hospitalized and ambulatory patients have extended well beyond orthopaedics. These techniques are not only used to control pain in patients undergoing major upper and lower extremity surgery, but also to provide perioperative analgesia in patients undergoing abdominal, plastic, urological, gynaecological, thoracic, and trauma surgeries. Infusion regimens of local anaesthetics and supplements must take into consideration the condition of the patient before and after surgery, the nature and intensity of the surgical stress associated with the surgery, and the possible need for immediate functional recovery. Continuous nerve blocks have proved safe and effective in reducing opioid consumption and related side-effects, accelerating recovery, and in many patients reducing the length of hospital stay. Continuous nerve blocks provide a safer alternative to epidural analgesia in patients receiving thromboprophylaxis, especially with low molecular-weight heparin.