Pharmacokinetics of 400 mg ropivacaine after periarticular local infiltration analgesia for total knee arthroplasty

Liberal use of local anaesthetic and the risk of toxicity in elective arthroplasties at a tertiary teaching hospital

Background

Local anaesthetic systemic toxicity (LAST) is a life-threatening potential complication that may follow the administration of local anaesthetic (LA) drugs, and is cumulative across the drug class. Local anaesthetics are commonly administered via different routes for elective orthopaedic procedures – both by anaesthetists and surgeons. We hypothesized that total doses of LA may be routinely encroaching upon toxicity.

Methods

All total hip or knee arthroplasties (THAs and TKAs) performed within a 3 month period at the John Hunter Hospital (tertiary referral centre and teaching hospital) were audited to assess total administration of LA. Demographics, surgical characteristics, use of general anaesthesia or sedation, and use of local anaesthetic via any route of administration was recorded. For each patient, a weight-based theoretical maximum safe dose was calculated and compared against the dose they received. Data is presented as mean ± SD, percentages. Statistical significance was determined at p < 0.05.

Results

130 THAs and TKAs were identified within the audit period. 52 patients exceeded their drug-class theoretical maximum safe dose. 49 patients exceeded their weight-based maximum dose for a single LA agent, in all cases ropivacaine. Non-obese individuals receive significantly higher mean dose than obese individuals (119.4% [98.6–140.3] vs 78.82% [65.95–91.69], p = 0.001). No LAST events were identified.

Conclusions

Patients who received elective total hip or knee arthroplasties were exposed to concerningly high total doses of local anaesthetic, suggesting that greater awareness of the additive toxicity of drugs within this class is required.

Local Anesthetic Systemic Toxicity After Local Infiltration Analgesia Following a Total Knee Arthroplasty

Multimodal analgesia is nowadays a recognized method to reduce postoperative pain. Infiltration of the surgical site with local anesthetic is one of the methods widely used for its effectiveness and its lower risk of toxicity, particularly in orthopedic surgery. We present here a case of local anesthetic systemic toxicity (LAST) that occurred on two different occasions to the same patient after total knee replacement surgeries. The clinical presentation of the syndrome was not typical for this 74-year-old patient who presented with respiratory distress associated with impaired consciousness. After the elimination of the most common diagnoses, it was finally the administration of Intralipid that followed with clinical improvement.

Orthostatic intolerance after fast-track knee arthroplasty: Incidence and hemodynamic pathophysiology

BACKGROUND

Early postoperative mobilization can be hindered by orthostatic intolerance (OI) due to failed orthostatic cardiovascular regulation. The underlying mechanisms are not fully understood and specific data after total knee arthroplasty (TKA) are lacking. Therefore, we evaluated the incidence of OI and the cardiovascular response to mobilization in fast-track TKA.

METHODS

This prospective observational cohort study included 45 patients scheduled for primary TKA in spinal anesthesia with a multimodal opioid-sparing analgesic regime. OI and the cardiovascular response to sitting and standing were evaluated with a standardized mobilization procedure preoperatively, and at 6h and 24h postoperatively. Hemodynamic variables were measured non-invasively (LiDCO™ Rapid). Perioperative bleeding, fluid balance, surgery duration, postoperative hemoglobin, opioid use and pain during mobilization were recorded.

RESULTS

Eighteen (44%) and 8 (22%) patients demonstrated OI at 6 and 24h after surgery respectively. Four (10%) and 2 (5%) patients experienced severe OI and terminated the mobilization procedure prematurely. Dizziness was the most common OI symptom during mobilization at 6h. OI was associated with decreased orthostatic responses in systolic, diastolic, mean arterial pressures and heart rate (all p<0.05), while severe OI patients demonstrated impaired diastolic, mean arterial pressures, heart rate and cardiac output responses (all p<0.05). No statistically significant differences in perioperative bleeding, fluid balance, surgery duration, postoperative hemoglobin, pain or opioid use were observed between orthostatic tolerant and intolerant patients.

CONCLUSION

Early postoperative OI is common following fast-track TKA. Pathophysiologic mechanisms include impaired orthostatic cardiovascular responses. The progression to severe OI symptoms appears to be primarily due to inadequate heart rate response.

Serum Concentration of Ropivacaine After Repeated Administration to Several Parts of the Head During Awake Craniotomy: A Prospective Cohort Study

Introduction

During awake craniotomy, effective use of local anesthetics, such as ropivacaine, is critical. Blood concentrations of ropivacaine after repeated administration over a short period during awake craniotomy have not been studied.

Materials and Methods

In this prospective cohort study, we evaluated serum concentrations of ropivacaine 15 min after each administration during awake craniotomy at Nagoya University Hospital between April 5, 2018 and August 31, 2019 to determine the safe dose. A total of 30 patients scheduled to undergo elective awake craniotomy were included. Patients were injected with 0.375% ropivacaine before the awake phase at the following points: scalp block (T1), headpin area (T2), skin incision area (T3), temporal muscle (T4), and dura mater (T5). Arterial blood samples were collected 15 min after ropivacaine administration. In addition to the blood concentrations of ropivacaine, complications during the awake phase were evaluated as secondary endpoints.

Results

The mean total dose of ropivacaine was 5.01 ± 0.68 mg/kg (maximum total dose: 6.30 mg/kg). The mean interval from T1 to T5 was 128.0 ± 17.7 min. The maximum serum concentration did not exceed the toxicity threshold of 4.3 μg/mL in any patient (mean serum concentration: T1, 1.23 ± 0.36 μg/mL; T5, 0.82 ± 0.26 μg/mL). No addiction symptoms were observed during awakening in any case.

Conclusion

Our results show that, in cases of awake craniotomy with repeated anesthetic administration, a total dose of up to 5.0 mg/kg is safe, without addiction symptoms. Relatively large amounts of ropivacaine can be safely injected during awake craniotomy.

Additional periarticular catheter shows no superiority over single-shot local infiltration analgesia alone in unicondylar knee replacement

PURPOSE

Local infiltration analgesia (LIA) has attracted growing interest in recent years. To prolong the positive effects of LIA, a continuous intraarticular perfusion has been introduced in total knee arthroplasty with good clinical results. The purpose of the present study was to evaluate if similar results can be obtained with the use of a continuous periarticular perfusion in unicondylar knee arthroplasty (UKA).

METHODS

50 consecutively selected patients undergoing UKA received either a single-shot LIA (control group; n = 25) or single-shot LIA combined with a continuous postoperative periarticular perfusion for 2 postoperative days (intervention group, n = 25). VAS (visual analogue scale) for pain, pain medication consumption and range of flexion were recorded postoperatively for 6 days. The catheter was removed after 2 days.

RESULTS

Only minor advantages of using a continuous periarticular catheter could be shown. Patients in the intervention group showed significant lower VAS scores on day 1 and required significant less pain medication on day 6. Further, there was a significant difference in the range of flexion on day 3, on which patients of the intervention group were able to bend the knee joint on average by 12° more than patients of the control group. On the other days, any significant differences between the two groups were not observed.

CONCLUSION

In summary, the present study could not identify any superiority of a periarticular catheter over single-shot LIA in UKA. Because of additional costs and the potential risk of infection, the conclusion of this study is to not recommend adding a periarticular catheter to the single-shot LIA in UKA.

LEVEL OF EVIDENCE

II.

Population pharmacokinetics of ropivacaine used for local infiltration anaesthesia during primary total unilateral and simultaneous bilateral knee arthroplasty

BACKGROUND

Ropivacaine is commonly used in local infiltration anaesthesia (LIA) as pain management after total knee arthroplasty (TKA). Although considered safe, no studies evaluated the pharmacokinetics of high-dose ropivacaine infiltration in simultaneous bilateral TKA.

METHODS

We studied 13 patients undergoing unilateral and 15 undergoing bilateral TKA. Standard LIA technique was used with ropivacaine 0.2%, 200 ml (400 mg) injected peri-articularly in each knee. Free and total plasma concentrations of ropivacaine were measured within 24 h using liquid chromatography-mass spectrometry. A population pharmacokinetic model was built using non-linear mixed-effects models.

RESULTS

Peak free ropivacaine concentration was 0.030 (0.017-0.071) μg ml^-1 (mean [99% confidence interval]) vs 0.095 (0.047-0.208) μg ml^-1, and peak total ropivacaine concentration was 0.756 (0.065-1.222) μg ml^-1vs 1.695 (0.077-3.005) μg ml^-1 for unilateral and bilateral TKA, respectively. The pharmacokinetics was ascribed a one-compartment model with first-order absorption. The main identified covariates were protein binding, allometrically scaled body weight on clearance and volume, and unilateral or bilateral surgery on volume.

CONCLUSIONS

This is the first study to investigate the pharmacokinetics of free and total ropivacaine after unilateral and bilateral TKA. A population model was successfully built and peak free ropivacaine concentration stayed below previously proposed toxic thresholds in patients undergoing unilateral and bilateral TKA receiving LIA with high-dose ropivacaine.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04702282.

Utilization of epinephrine-soaked gauzes to address bleeding from osteotomy sites in non-tourniquet total knee arthroplasty: a retrospective cohort study

Background

Reducing tourniquet inflation time is important because of the complications of tourniquet extensively used for the control of hemorrhage in total knee arthroplasty (TKA). Bleeding management is critical to acquire a relative bloodless arthrotomy interface for maximize cement fixation in non-tourniquet TKA. The purpose of this study was to investigate hemostatic and hemodynamic effects of epinephrine-soaked gauzes in cemented TKAs.

Methods

A retrospective cohort study of 101 patients in two groups was performed. The first group (n = 51) underwent unilateral TKA with our procedures of epinephrine use, the second group (n = 50) had the same protocol with tourniquet and no epinephrine utilization. Surgical field visualization was assessed by grading scale for difficulty of intraoperative visualization due to blood and number of surgical field clearances. Perioperative blood loss was recorded. Hemodynamic parameters were observed in the epinephrine group.

Results

There was statistically significant difference (p < 0.01) on surgeon-rated difficulty in visualization in the epinephrine group between before and after use of epinephrine, and no statistically significant difference (p = 0.96) between two groups before cementing. No statistically significant result on numbers of surgical field clearances between two groups (p = 0.25) was found. Epinephrine group showed significant difference in hidden blood loss compared with no epinephrine group (576.6 ± 229.3 vs 693.2 ± 302.9, respectively, p = 0.04). The hemodynamic effects of epinephrine may be under control.

Conclusion

The procedure of epinephrine soaked gauzes, as a prudent adjunct, may be effective to reduce blood loss and obtain bloodless bone sections in non-tourniquet TKAs, regardless of hemodynamics.

Local infiltration analgesia for total knee arthroplasty: Does a mixture of ropivacaine and epinephrine have an impact on hemodynamics? An observational cohort study

Purpose:

High doses of local anesthetic administered intra-articularly and peri-articularly during local infiltration analgesia (LIA) for total knee arthroplasty (TKA) may have potential effects on patient hemodynamics. The aim of this study was to know if hemodynamic changes are associated with LIA in patients undergoing TKA.

Methods:

In a prospective observational design, elective patients undergoing orthopedic surgery for TKA and treated with LIA consisting of a mixture of ropivacaine (300 mg) and epinephrine (1 mg) were investigated for changes in selected hemodynamic parameters: heart rate (HR), non-invasively registered mean arterial blood pressure (MAP), and incidence of arrhythmias during the perioperative course, consisting of the following periods: period 1. from establishment of spinal anesthesia to prior to LIA administration, period 2. from administration of LIA to before release of ischemia tourniquet, period 3. from release ischemia tourniquet to end of surgery, and period 4. from transfer to the post anesthesia care unit to the ward. Statistical analysis was done with ANOVA-RM for the difference in means in repeated measurements, and with the Tukey Test between pairs. Data are presented as mean ± standard deviation. A P value <0.05 was considered significant.

Results:

Ninety-nine patients (mean age 77 ± 8 years) were included. HR increased from period 2 to period 3 up to 16% (67 ± 14 to 77 ± 13 bpm, P < 0.001), and from period 2 to period 4 up to 21% (67 ± 14 to 81 ± 12 bpm, P < 0.001). MAP showed no significant changes from period 2 to period 3 (89 ± 13 to 87 ± 13 mmHg, P > 0.50), and from period 2 to period 4 (89 ± 13 to 91 ± 11 mmHg, P > 0.50). No arrhythmias were detected during follow-up.

Conclusions:

A mixture of ropivacaine and epinephrine for LIA, despite the high doses administered, does not have a negative impact on hemodynamics.

[Pain concepts in fast-track endoprosthetics]

An effective and safe pain management is nowadays a pivotal component of fast-track endoprosthetics. The analgesic strategies should be opioid-sparing whenever possible because opioids induce side-effects that reduce the well-being of patients and are even associated with a risk of falling. This is not compatible with a fast mobilization. In order to achieve this goal, multimodal pain concepts have proven to be suitable. Decentralized analgesia with epidural and regional catheters as well as the use of local infiltration anesthesia (LIA) can be used; however, catheters are also associated with a muscular deficit and the danger of falling. Therefore, in the fast-track concepts LIA has become established. With respect to knee endoprosthetics many studies have shown that LIA achieves at least comparable results or even superiority in comparison with the use of catheters. It represents a safe and effective procedure with respect to postoperative analgesia and accelerated mobilization. A variety of protocols for the use of LIA can currently be found in the literature. In addition to analgesics the supportive administration of glucocorticoids is increasingly being used, which also reduce pain due to the anti-inflammatory effect; however, regarding this aspect relatively few prospective randomized studies in comparison to LIA are available in the literature.

The Hemodynamic Effect of Epinephrine-Containing Local Infiltration Analgesia After Tourniquet Deflation During Total Knee Arthroplasty: A Retrospective Observational Study

BACKGROUND

Local infiltration analgesia (LIA) is widely used in patients undergoing total knee arthroplasty and often contains epinephrine for a prolonged analgesic effect and to reduce systemic absorption of the local anesthetic. This retrospective observational study investigated the hemodynamic effect of locally infiltrated epinephrine after deflation of the tourniquet during total knee arthroplasty.

METHODS

We reviewed the electronic medical records of patients who underwent total knee arthroplasty between January 2017 and February 2018 at a tertiary care university hospital. Total knee arthroplasty was performed using a conventional technique with a pneumatic tourniquet. LIA consisted of ropivacaine, morphine sulfate, ketorolac, and methylprednisolone. The patients were grouped according to whether or not epinephrine was included in the LIA. The incidence of a hypertensive response (systolic blood pressure >160 mmHg or mean blood pressure >110 mmHg) after deflation of the tourniquet was compared between the 2 groups.

RESULTS

A total of 452 patients had received LIA with (n = 188) or without (n = 264) epinephrine. A hypertensive response after deflation of the tourniquet was more common in patients who received LIA containing epinephrine (42/188 [22.3%]) than in those who received LIA without epinephrine (14/264 [5.3%], P < .001). However, the incidence of hypotension after deflation of the tourniquet was not significantly different between the 2 groups (P = .976).

CONCLUSION

Because epinephrine-containing LIA can result in a hypertensive response after deflation of the tourniquet during total knee arthroplasty, it should be cautiously administered, especially in patients with cardiovascular comorbidities.

Continuous Adductor Canal Block used for postoperative pain relief after medial Unicondylar Knee Arthroplasty: a randomized, double-blind, placebo-controlled trial

Background

Peripheral nerve block and local infiltration analgesia (LIA) provide good analgesia after knee replacement. This study evaluated the additional analgesic efficacy of continuous adductor canal block (ACB) added to single-dose LIA after medial unicondylar knee arthroplasty (UKA). We hypothesized ACB would lower pain scores and facilitate postoperative ambulation.

Methods

Forty-six patients were enrolled into this double-blind, randomized, placebo-controlled trial. UKA was performed and all patients received single-dose LIA intraoperatively. Patients were randomized into two groups: Group RP receiving 0.2% ropivacaine or Group Con receiving normal saline. A flow at 6 mL/h was administered for 48 h through a catheter in the adductor canal. Primary outcome was movement pain score at 24 h using the numeric rating scale (NRS-11). Secondary outcomes included serial postoperative pain scores, rate of patients with NRS>3 at rest and movement within 24 and 48 h postoperatively, time to breakthrough pain, quadriceps motor strength, ambulated distance, catheter related infection and patient satisfaction.

Results

Forty-two patients were analyzed. Pain scores with movement at 24 h postoperatively were significantly lower in Group RP than that in Group Con (3 vs. 5 NRS, P<0.001). Compared with Group Con, breakthrough pain occurred later in Group RP (18.5 vs 10.0 h, P = 0.002), serial pain scores at rest and with movement and rate of patients with NRS>3 with movement after surgery were significantly lower. Quadriceps motor strength was equivalent, however, ambulated distance on postoperative day 1 and 2 in Group Con was significant less (19.7 vs 37.3 m, P = 0.046; 33.4 vs 59.5 m, P = 0.002).

Conclusions

Continuous adductor canal block added to single-dose LIA offered better analgesia and facilitated ambulation without motor weakness after medial UKA.

Trial registration

Clinical Trial Registration: ChiCTR-IOR-16008720; Registered 25 June 2016.

Serum ropivacaine levels after local infiltration analgesia during total knee arthroplasty with and without adductor canal block

BACKGROUND AND OBJECTIVES

A common analgesic technique for total knee arthroplasty (TKA) is to inject local anesthetic into the periarticular tissue during surgery, known as local infiltration analgesia (LIA). Since the solution used typically contains a large amount of local anesthetic, concerns arise about exceeding the maximum dosage when adding a peripheral nerve block. Little research exists that addresses serum ropivacaine concentrations following LIA combined with peripheral nerve block. We hypothesized that after combining LIA and adductor canal blockade (ACB), serum ropivacaine concentrations would remain below levels associated with local anesthetic toxicity.

METHODS

This was a prospective observational study that included 14 subjects undergoing TKA with intraoperative LIA containing 270 mg ropivacaine with epinephrine. Patients weighing less than 80 kg were excluded due to standardized dosing by our pharmacy. Seven patients were assigned consecutively to receive LIA alone (Group LIA) and seven were assigned to receive LIA plus ACB with 100 mg ropivacaine with epinephrine (Group LIA+ACB). Venous serum ropivacaine concentrations were measured over 24 hours.

RESULTS

Peak serum concentrations (Cmax) in Group LIA ranged from 0.23 to 0.75 µg/mL and occurred at times from 4 to 24 hours. Cmax in Group LIA+ACB ranged from 0.46 to 1.00 µg/mL and occurred at times from 4 to 8 hours. No participants demonstrated signs or symptoms of local anesthetic toxicity.

CONCLUSIONS

Total serum concentration of ropivacaine after LIA using 270 mg ropivacaine with and without an additional 100 mg perineural ropivacaine remained well below the toxicity threshold of 3.0 µg/mL at all time points. Additional studies are needed to ascertain the safety of combining LIA with peripheral nerve blockade.

Pharmacokinetics of 400 mg Locally Infiltrated Ropivacaine After Total Knee Arthroplasty Without Perioperative Tourniquet Use

BACKGROUND AND OBJECTIVES

Local infiltration analgesia (LIA) with ropivacaine for total knee arthroplasty (TKA) is increasingly used. Despite the high doses of ropivacaine, LIA is considered safe, and this perception is sustained by pharmacokinetic data demonstrating that maximum concentrations of ropivacaine stay well below the toxic threshold in plasma. These pharmacokinetic studies all involve TKA procedures with the use of a tourniquet. Recently, performing TKA without the use of a tourniquet is gaining popularity, but no pharmacokinetic data exist when LIA is administered for TKA without the use of a tourniquet. The purpose of this study was to describe the pharmacokinetic profile of a single-shot ropivacaine (200 mL 0.2%) and 0.75 mg epinephrine (1000 μg/mL) when used for LIA in patients for TKA without a tourniquet.

METHODS

In this prospective cohort study, 20 patients treated with LIA for TKA without a tourniquet were studied. Plasma samples were taken at 20, 40, 60, 90, 120, 240, 360, 480, 600, 720, and 1440 minutes after local anesthetic infiltration, in which total and unbound ropivacaine concentrations were determined.

RESULTS

Results are given as median (interquartile range [IQR]). Median peak ropivacaine concentration was 1.16 μg/mL (IQR, 0.46); median peak unbound ropivacaine concentration was 0.05 μg/mL (IQR, 0.02). The corresponding times to reach the maximum concentration for total and unbound ropivacaine were 360 (IQR, 240) and 360 (IQR, 360) minutes, respectively.

CONCLUSIONS

Although great interindividual variability in ropivacaine concentration was found, both total and unbound maximum serum concentrations remained below the assumed systemic toxic thresholds in all samples.

CLINICAL TRIAL REGISTRATION

This study was registered at Netherlands Trial Registry (http://www.trialregister.nl), trial ID NTR6306.

Local anesthetic systemic toxicity: current perspectives

Local anesthetic systemic toxicity (LAST) is a life-threatening adverse event that may occur after the administration of local anesthetic drugs through a variety of routes. Increasing use of local anesthetic techniques in various healthcare settings makes contemporary understanding of LAST highly relevant. Recent data have demonstrated that the underlying mechanisms of LAST are multifactorial, with diverse cellular effects in the central nervous system and cardiovascular system. Although neurological presentation is most common, LAST often presents atypically, and one-fifth of the reported cases present with isolated cardiovascular disturbance. There are several risk factors that are associated with the drug used and the administration technique. LAST can be mitigated by targeting the modifiable risk factors, including the use of ultrasound for regional anesthetic techniques and restricting drug dosage. There have been significant developments in our understanding of LAST treatment. Key advances include early administration of lipid emulsion therapy, prompt seizure management, and careful selection of cardiovascular supportive pharmacotherapy. Cognizance of the mechanisms, risk factors, prevention, and therapy of LAST is vital to any practitioner using local anesthetic drugs in their clinical practice.

Effect of local infiltration analgesia, peripheral nerve blocks, general and spinal anesthesia on early functional recovery and pain control in unicompartmental knee arthroplasty

Background

The aim of the study was to analyze the effect of local infiltration analgesia (LIA), peripheral nerve blocks, general and spinal anesthesia on early functional recovery and pain control in primary unicompartmental knee arthroplasty (UKA).

Methods

Between January 2016 until August 2016, 134 patients underwent primary UKA and were subdivided into four groups according to their concomitant pain and anesthetic procedure with catheter-based techniques of femoral and sciatic nerve block (group GA&FNB, n = 38) or epidural catheter (group SP&EPI, n = 20) in combination with general anesthesia or spinal anesthesia, respectively, and LIA combined with general anesthesia (group GA&LIA, n = 46) or spinal anesthesia (group SP&LIA, n = 30). Outcome parameters focused on the evaluation of pain (NRS scores), mobilization, muscle strength and range of motion up to 7 days postoperatively. The cumulative consumption of (rescue) pain medication was analyzed.

Results

The LIA groups revealed significantly lower (about 50%) mean NRS scores (at rest) compared to the catheter-based groups at the day of surgery. In the early postoperative period, the dose of hydromorphone as rescue pain medication was significantly lower (up to 68%) in patients with SP&EPI compared to all other groups. No significant differences could be detected with regard to grade of mobilization, muscle strength and range of motion. However, there seemed to be a trend towards improved mobilization and muscle strength with general anesthesia and LIA, whereof general anesthesia generally tended to ameliorate mobilization.

Conclusions

Except for a significant lower NRS score at rest in the LIA groups at day of surgery, pain relief was comparable in all groups without clinically relevant differences, while the use of opioids was significantly lower in patients with SP&EPI. A clear clinically relevant benefit for LIA in UKA cannot be stated. However, LIA offers a safe and effective treatment option comparable to the well-established conventional procedures.

Effect of local infiltration analgesia, peripheral nerve blocks, general and spinal anesthesia on early functional recovery and pain control in total knee arthroplasty

BACKGROUND

Postoperative pain control and enhanced mobilization, muscle strength and range of motion following total knee arthroplasty (TKA) are pivotal requisites to optimize rehabilitation and early recovery. The aim of the study was to analyze the effect of local infiltration analgesia (LIA), peripheral nerve blocks, general and spinal anesthesia on early functional recovery and pain control in primary total knee arthroplasty.

METHODS

Between January 2016 until August 2016, 280 patients underwent primary TKA and were subdivided into four groups according to their concomitant pain and anesthetic procedure with catheter-based techniques of femoral and sciatic nerve block (group GA&FNB, n = 81) or epidural catheter (group SP&EPI, n = 51) in combination with general anesthesia or spinal anesthesia, respectively, and LIA combined with general anesthesia (group GA&LIA, n = 86) or spinal anesthesia (group SP&LIA, n = 61). Outcome parameters focused on the evaluation of pain (NRS scores), mobilization, muscle strength and range of motion up to 7 days postoperatively. The cumulative consumption of (rescue) pain medication was analyzed.

RESULTS

Pain relief was similar in all groups, while the use of opioid medication was significantly lower (up to 58%) in combination with spinal anesthesia, especially in SP&EPI. The LIA groups, in contrast, revealed significant higher mobilization (up to 26%) and muscle strength (up to 20%) in the early postoperative period. No analgesic technique-related or surgery-related complications occurred within the first 7 days. Due to insufficient pain relief, 8.4% of the patients in the catheter-based groups and 12.2% in the LIA groups resulted in a change of the anesthetics pain management.

CONCLUSIONS

The LIA technique offers a safe and effective treatment option concerning early functional recovery and pain control in TKA. Significant advantages were shown for mobilization and muscle strength in the early postoperative period while pain relief was comparable within the groups.

Adductor canal block with local infiltrative analgesia compared with local infiltrate analgesia for pain control after total knee arthroplasty: A meta-analysis of randomized controlled trials

BACKGROUND

This meta-analysis aimed to evaluate the efficiency and safety of the combined adductor canal block with peri-articular infiltration versus periarticular infiltration alone for pain control after total knee arthroplasty (TKA).

METHODS

PubMed, Medline, Embase, Web of Science, and the Cochrane Library were searched to identify articles comparing the combined adductor canal block with peri-articular infiltration and periarticular infiltration alone for pain control after TKA. Main outcomes were numeric rating scale (NRS) at postoperative day (POD) 0-2 and opioid consumption. Meta-analysis was performed using Stata 11.0 software.

RESULTS

Four randomized controlled trial (RCTs) including 297 patients met the inclusion criteria. The present meta-analysis indicated that there were significant differences between the groups regarding NRS score at POD 0 (weighted mean difference [WMD] = -0.849, 95% confidence interval [CI]: -1.345 to -0.353, P = .001), POD 1 (WMD = -0.960, 95% CI: -1.474 to -0.446, P = .000), and POD 2 (WMD = -0.672, 95% CI: -1.163 to -0.181, P = .007) after TKA. Significant differences were found in terms of opioid consumption at POD 0 (WMD = -3.761, 95% CI: -6.192 to -1.329, P = .002), POD 1 (WMD = -4.795, 95% CI: -8.181 to -1.409, P = .006), and POD 2 (WMD = -2.867, 95% CI: -4.907 to -0.827, P = .006).

CONCLUSION

Combined adductor canal block with peri-articular infiltration could significantly reduce NRS scores and opioid consumption in comparison with periarticular infiltration alone following TKA. Additionally, there is a lower incidence of nausea and vomiting in the combined groups.