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Background and purpose

Pain after total knee arthroplasty (TKA) is usually severe, and epidural analgesia or femoral nerve block has been considered to be an effective pain treatment. Recently, local infiltration analgesia (LIA) has become increasingly popular but the outcome of this method regarding the analgesic effect has not been fully evaluated. We compared local infiltration analgesia and femoral block with regard to analgesia and morphine demand during the first 24 h after TKA.

Methods

40 patients undergoing TKA under spinal anesthesia were randomized to receive femoral nerve block (group F) or peri- and intraarticular infiltration analgesia (group LIA) with a mixture containing ropivacaine, ketorolac, and epinephrine. All patients had access to intravenous patient-controlled analgesia (PCA) with morphine postoperatively. Pain intensity at rest and upon movement was assessed on a numeric rating scale (0–10) on an hourly basis over 24 h if the patients were awake.

Results

The average pain at rest was marginally lower with LIA (1.6) than with femoral block (2.2). Total morphine consumption per kg was similar between the 2 groups. Ancillary analysis revealed that 1 of 20 patients in the LIA group reported a pain intensity of > 7 upon movement, as compared to 7 out of 19 in the femoral block group (p = 0.04).

Interpretation

Both LIA and femoral block provide good analgesia after TKA. LIA may be considered to be superior to femoral block since it is cheaper and easier to perform.

Background and purpose

Postoperative pain is often severe after total knee arthroplasty (TKA). We investigated the efficacy of the local infiltration analgesia (LIA) technique, both intraoperatively and postoperatively.

Methods

48 patients undergoing TKA were randomized into 2 groups in a double-blind study. In group A, 400 mg ropivacaine, 30 mg ketorolac, and 0.5 mg epinephrine were infiltrated periarticularly during operation. In group P, no injections were given. 21 h postoperatively, 200 mg ropivacaine, 30 mg ketorolac, and 0.1 mg epinephrine were injected intraarticularly in group A, and the same volume of saline was injected in group P. All patients were followed up for 3 months.

Results

Median morphine consumption was lower in group A during the first 48 h: 18 (1–74) mg vs. 87 (36–160) mg in group P. Postoperative pain was lower at rest in group A during the first 27 h, and on movement during the first 48 h, except at 21 h. Time to fulfillment of discharge criteria was shorter in group A than in group P: 3 (1–7) vs. 5 (2–8) days. Patient satisfaction was higher in group A than in group P on days 1 and 7. The unbound venous blood concentration of ropivacaine was below systemic toxic blood concentrations.

Interpretation

The local infiltration analgesia (LIA) technique provides excellent pain relief and lower morphine consumption following TKA, resulting in shorter time to home readiness and higher patient satisfaction. There were few side effects and systemic LA concentrations were low.

Background and purpose

Ropivacaine infusion following high-volume local infiltration analgesia has been shown to be effective after total knee arthroplasty, but the optimum site of administration of ropivacaine has not been evaluated. We compared the effects of intraarticular and extraarticular adminstration of the local anesthetic for postoperative supplementation of high-volume local infiltration analgesia.

Patients and methods

In this double-blind study, 36 rheumatic patients aged 51–78 years with physical status ASA 2–3 who were scheduled for total knee arthroplasty were randomized into 2 groups. All patients received wound infiltration at the end of surgery with 300 mg ropivacaine, 30 mg ketorolac, and 0.5 mg epinephrine (total volume 156 mL). A tunneled catheter was randomly placed either extraarticularly or intraarticularly. Continuous infusion of ropivacain (0.5%, 2 mL/h) was started immediately and was maintained during the next 48 h. Pain intensity at rest, on movement, and with mobilization was estimated by the patients and the physiotherapist; rescue morphine consumption was recorded.

Results

As estimated by the patients, ropivacaine administered intraarticularly did not improve analgesia relative to extraarticular infusion, but improved the first mobilization. The incidence of high intensity of pain (VAS 7–10) was less in the group with intraarticular infusion. Analgesic requirements were similar in the 2 groups (47 mg and 49 mg morphine). No complications of postoperative wound healing were seen and there were no toxic side effects.

Interpretation

Continuous infusion of ropivacaine intraarticulary did not improve postoperative analgesia at rest relative to extraarticular administration, but it appeared to reduce the incidence of high pain intensity during first exercises, and could therefore be expected to improve mobilization up to 24 h after total knee arthroplasty.

Total knee arthroplasty (TKA) is a commonly performed procedure for the treatment of end-stage arthritis of the knee. Pain control following TKA is difficult to manage in some patients. We examined the use of a postoperative intraarticular injection of 100 mL of 0.2% (200 mg) ropivacaine in a double-blind, prospective, placebo-controlled pilot study to evaluate its use as a pain control modality. All patients received general anesthesia. Postoperatively, patients were placed on intravenous patient-controlled analgesia with morphine. The ropivacaine group showed an early trend in lower visual analog scale (VAS) scores when compared with the placebo group. Patients receiving ropivacaine used a similar amount of narcotics compared with the placebo group. Intraarticular ropivacaine used for pain control after TKA demonstrated no statistically significant difference in lowering VAS scores or narcotic usage; therefore, intraarticular ropivacaine as a single modality is not recommended for effective pain management.

INTRODUCTION

Adequate peri-operative analgesia following total knee arthroplasty (TKA) promotes earlier rehabilitation but remains problematic because of the drug side-effects. Peri-articular multimodal drug infiltration (PMDI) has been developed as an alternative strategy to avoid such complications. Autologous retransfusion drains reduce the need for peri-operative allogenic blood transfusions and the consequent risk. There is a theoretical risk of local anaesthesia toxicity when these systems are used concurrently. We performed a review of current practice to quantify this risk.

PATIENTS AND METHODS

A series of 10 patients undergoing TKA by the senior author (CAB) had drain fluid analysed for the concentration of ropivacaine. At the same time, the patients completed a questionnaire to establish the presence of ropiva-caine-induced side-effects.

RESULTS

The ropivacaine level in the retransfusion blood was less than 10 mg in all patients. This concentration was a factor of 6 below the published safe level. Three patients had minor neurological disturbances which recovered spontaneously and quickly. There were no cases of significant cardiovascular compromise.

CONCLUSIONS

The theoretical risk of local anaesthesia toxicity when these systems are used together is negligible and we conclude that peri-articular multimodal drug infiltration is safe in conjunction with the use of autotransfusion drains.

Background and purpose

Postoperative analgesia after primary total hip arthroplasty (THA) using opioids is associated with troublesome side effects such as nausea and dizziness, and epidural analgesic means delayed mobilization. Thus, local infiltration analgesia (LIA) during surgery prolonged with local infusion analgesia (LINFA) into the soft tissue in the hip region through a catheter in the first postoperative days has gained major interest in THA fast-track settings within a short period of time. LIA at the time of surgery is a validated treatment. We investigated the additional effect of giving postoperative LINFA after THA in patients already having LIA during surgery.

Patients and methods

60 consecutive patients undergoing non-cemented THA were randomized into two groups in a double-blind and controlled study. During surgery, all patients received standardized pain treatment with LIA. Postoperatively, they were treated either with a solution of Ropivacain, Ketorolac, and Adrenaline (LINFA group) or placebo (placebo group) administered through a catheter to the hip 10 and 22 h after surgery. Pain score, opioid consumption, and length of stay (LOS) were evaluated.

Results

After adjustment for multiple testing, there was no statistically significant postoperative difference between the LINFA group and the placebo group regarding pain and tiredness. We found some evidence of a short-term effect on nausea and vomiting. Opioid consumption and length of stay were similar in the two groups.

Interpretation

We found some evidence of a short-term effect of LINFA on nausea and vomiting, but no evidence of an effect on postoperative pain and tiredness. Thus, LINFA cannot be recommended as a standard pain treatment in patients with THA.

Background and purpose

High-volume infiltration analgesia may be effective in postoperative pain management after hip arthroplasty but methodological problems prevent exact interpretation of previous studies.

Methods

In a randomized, double-blind placebo-controlled trial in 12 patients undergoing bilateral total hip arthroplasty (THA) in a fast-track setting, saline or high-volume (170 mL) ropivacaine (0.2%) with epinephrine (1:100,000) was administered to the wound intraoperatively along with supplementary postoperative injections via an intraarticular epidural catheter. Oral analgesia was instituted preoperatively with a multimodal regimen (gabapentin, celecoxib, and acetaminophen). Pain was assessed repeatedly for 48 hours postoperatively, at rest and with 45° hip flexion.

Results

Pain scores were low and similar between ropivacaine and saline administration. Median hospital stay was 4 (range 2–7) days.

Interpretation

Intraoperative high-volume infiltration with 0.2% ropivacaine with repeated intraarticular injections postoperatively may not give a clinically relevant analgesic effect in THA when combined with a multimodal oral analgesic regimen with gabapentin, celecoxib, and acetaminophen.

Background and purpose

There has recently been interest in the advantages of minimally invasive surgery (MIS) over conventional surgery, and on local infiltration analgesia (LIA) during knee arthroplasty. In this randomized controlled trial, we investigated whether MIS would result in earlier home-readiness and reduced postoperative pain compared to conventional unicompartmental knee arthroplasty (UKA) where both groups received LIA.

Patients and methods

40 patients scheduled for UKA were randomized to a MIS group or a conventional surgery (CON) group. Both groups received LIA with a mixture of ropivacaine, ketorolac, and epinephrine given intra- and postoperatively. The primary endpoint was home-readiness (time to fulfillment of discharge criteria). The patients were followed for 6 months.

Results

We found no statistically significant difference in home-readiness between the MIS group (median (range) 24 (21–71) hours) and the CON group (24 (21–46) hours). No statistically significant differences between the groups were found in the secondary endpoints pain intensity, morphine consumption, knee function, hospital stay, patient satisfaction, Oxford knee score, and EQ-5D. The side effects were also similar in the two groups, except for a higher incidence of nausea on the second postoperative day in the MIS group.

Interpretation

Minimally invasive surgery did not improve outcome after unicompartmental knee arthroplasty compared to conventional surgery, when both groups received local infiltration analgesia. The surgical approach (MIS or conventional surgery) should be selected according to the surgeon’s preferences and local hospital policies.

ClinicalTrials.gov. (Identifier NCT00991445).

Recent publications have established that intraoperative autotransfusion (IAT) may be applied to reduce homologous banked blood utilization for patients undergoing major orthopaedic surgery.

This study addresses the value of combining IAT with postoperative blood salvage and recovery. Perioperative blood loss associated with primary total knee and hip prosthetic replacements was reviewed from the time of surgery through the third postoperative day. A technique for autologous blood replacement, including perioperative salvage, is described.

The use of homologous (banked) blood can be significantly reduced by utilizing IAT, postoperative salvage, and autologous blood replacement.

Images

We prospectively randomised 104 consecutive patients undergoing primary cemented total knee arthroplasty into two groups of 52 patients each, with one group to receive a standard suction drain (Redivac) and the other, an autologous transfusion drain (Bellovac). Randomisation was achieved using the software programme MINIM, which was set to randomly allocate patients to either of the two groups based on their age, sex and body mass index (BMI). All procedures were performed under pneumatic tourniquet. Drains were released in the recovery room 20 min after surgery and removed 24 h following surgery. Blood collected in the standard suction drain (control group) was discarded, while blood collected in the autologous transfusion drains (study group) was transfused unwashed back to the patient within 6 h of collection. Thirteen patients (25%) in the study group had two or more units of homologous blood transfused in addition to the blood collected postoperatively and re-transfused (average: 438 ml). Twelve patients (23%) in the control group had two or more units of homologous blood transfused. No sepsis, transfusion reactions or coagulopathies were associated with the autologous blood transfused in the study group. The use of the autologous transfusion system (Bellovac) proved to be safe but failed to reduce the need for postoperative homologous blood transfusion following uncomplicated total knee arthroplasty.

Background

There have been few studies describing wound infiltration with additional intraarticular administration of multimodal analgesia for total knee arthroplasty (TKA). In this study, we assessed the efficacy of wound infiltration combined with intraarticular regional analgesia with epidural infusion on analgesic requirements and postoperative pain after TKA.

Methods

40 consecutive patients undergoing elective, primary TKA were randomized into 2 groups to receive either (1) intraoperative wound infiltration with 150 mL ropivacaine (2 mg/mL), 1 mL ketorolac (30 mg/mL), and 0.5 mL epinephrine (1 mg/mL) (total volume 152 mL) combined with intraarticular infusion (4 mL/h) of 190 mL ropivacaine (2 mg/mL) plus 2 mL ketorolac (30 mg/mL) (group A), or (2) epidural infusion (4 mL/h) of 192 mL ropivacaine (2 mg/mL) combined with 6 intravenous administrations of 0.5 mL ketorolac (30 mg/mL) for 48 h postoperatively (group E). For rescue analgesia, intravenous patient-controlled-analgesia (PCA) morphine was used.

Morphine consumption, intensity of knee pain (0–100 mm visual analog scale), and side effects were recorded. Length of stay and corrected length of stay were also recorded (the day-patients fulfilled discharge criteria).

Results

The median cumulated morphine consumption, pain scores at rest, and pain scores during mobilization were reduced in group A compared to group E. Corrected length of stay was reduced by 25% in group A compared to group E.

Interpretation

Peri- and intraarticular analgesia with multimodal drugs provided superior pain relief and reduced morphine consumption compared with continuous epidural infusion with ropivacaine combined with intravenous ketorolac after TKA.

Background and purpose The degree of postoperative pain is usually moderate to severe following knee arthroplasty. We investigated the efficacy of local administration of analgesics into the operating area, both intraoperatively and postoperatively.

Methods 40 patients undergoing unicompartmental knee arthroplasty (UKA) were randomized into 2 groups in a double–blind study (ClinicalTrials.gov identifier: NCT00653926). In group A (active), 200 mg ropivacaine, 30 mg ketorolac, and 0.5 mg epinephrine (total volume 106 mL) were infiltrated intraoperatively into the soft tissue, while in group P (placebo), no injections were given. 21 hours postoperatively, 150 mg ropivacain, 30 mg ketorolac, and 0.1 mg epinephrine were injected intraarticularly via a catheter in group A, whereas patients in group P were injected with the same volume of saline (22 mL).

Results Median hospital stay was shorter in group A than in group P: 1 (1–6) days as opposed to 3 (1–6) days (p < 0.001). Postoperative pain in group A was statistically significantly lower at rest after 6 h and 27 h and on movement after 6, 12, 22, and 27 h. Morphine consumption was statistically significantly lower in group A for the first 48 h, resulting in a lower frequency of nausea, pruritus, and sedation. Postoperatively, there were improved functional scores (Oxford knee score and EQ–5D) in both groups relative to the corresponding preoperative values.

Interpretation Local injection of analgesics periarticularly at the end of the operation and intraarticularly at 21 h postoperatively provided excellent pain relief and earlier home discharge following UKA. There was a high degree of patient satisfaction in both groups after 6 months (Clinical Trials.gov: NCT 00653926).

We designed this study to evaluate the effect of small-dose intravenous ketamine in combination with continuous femoral nerve block on postoperative pain and rehabilitation after total knee arthroplasty. Continuous femoral nerve block with ropivacaine was started before surgery and continued in the surgical ward for 48 h. Patients were randomly assigned to receive an initial bolus of 0.5 mg/kg ketamine followed by a continuous infusion of 3 μg·kg-1·min-1 during surgery and 1.5 μg·kg-1·min-1 for 48 h (Ketamine group) or an equal volume of saline (Control group). Additional postoperative analgesia was provided by patient-controlled intravenous morphine. Pain scores and morphine consumption were recorded over 48 hours. The maximal degree of active knee flexion tolerated was recorded daily until hospital discharge. Follow up was performed 6 weeks and 3 months after surgery. The Ketamine group required significantly less morphine than the Control group (45 ± 20 mg versus 69 ± 30 mg; P < 0.02). Patients in the Ketamine group reached 90° of active knee flexion more rapidly than those in the Control group (P < 0.02). Outcomes at 6 weeks and 3 months were similar in each group. These results confirm that ketamine is a useful analgesic adjuvant in perioperative multimodal analgesia with a positive impact on early knee mobilization.

Transfusion-induced hyperkalemia can lead to cardiac arrest, especially when the patient rapidly receives a large amount of red blood cells (RBCs), previously stored for a long period of time, irradiated or both. We report on a case of application of the Continuous AutoTransfusion System (CATS) to wash RBCs, in order to lower the high potassium (K+) level in the packed RBCs unit, during massive transfusion following transfusion-induced hyperkalemic cardiac arrest. After the washing process using CATS, there was no more electrocardiographic abnormality or cardiac arrest due to hyperkalemia. This case emphasizes the potential risk to develop transfusion-related hyperkalemic cardiac arrest, during massive transfusion of irradiated, pre-stored RBCs. CATS can be effectively used to lower the K+ concentration in the packed RBCs unit, especially when the risk of transfusion-induced hyperkalemia is high.

Background

Patient-controlled analgesia is a widely used and effective method of controlling pain after THA. This method is associated with substantial undesirable side effects. Local infiltration has been introduced in an attempt to reduce opioid requirements postoperatively, but its ability to reduce pain without complications is still questioned.

Questions/Purposes

We evaluated patient-controlled analgesia use, pain and satisfaction scores, complication rates, and ropivacaine levels associated with the use of periarticular multimodal drug infiltration in THA.

Patients and Methods

We randomized 64 patients undergoing THA to receive a periarticular intraoperative multimodal drug injection or to receive no injection. All patients received patient-controlled analgesia for 24 hours after surgery. The final assessment was at 6 weeks.

Results

Patients receiving the periarticular injection used less patient-controlled analgesia 6 hours postoperatively. The 24-hour patient-controlled analgesia requirement postsurgery also was less. The visual analog scale score for pain on activity in the postanesthetic care unit was less for patients who received an injection. The visual analog scale satisfaction score was similar in the two groups throughout the followup period. Recorded unbound ropivacaine levels were 2.5 times lower than toxic levels.

Conclusions

Periarticular intraoperative injection with multimodal drugs can reduce postoperative patient-controlled analgesia requirements and pain on activity in patients undergoing THA with no apparent increase in risk.

Level of Evidence

Level I, therapeutic study. See the guidelines online for a complete description of level of evidence.

A continuous femoral nerve block (cFNB) involves the percutaneous insertion of a catheter adjacent to the femoral nerve, followed by a local anesthetic infusion, improving analgesia following total knee arthroplasty (TKA). Portable infusion pumps allow infusion continuation following hospital discharge, raising the possibility of decreasing hospitalization duration. We therefore used a multicenter, randomized, triple-masked, placebo-controlled study design to test the primary hypothesis that a four-day ambulatory cFNB decreases the time until each of three predefined readiness-for-discharge criteria (adequate analgesia, independence from intravenous opioids, and ambulation ≥ 30 meters) are met following TKA compared with an overnight inpatient-only cFNB. Preoperatively, all patients received a cFNB with perineural ropivacaine 0.2% from surgery until the following morning, at which time they were randomized to either continue perineural ropivacaine (n=39) or switch to normal saline (n=38). Patients were discharged with their cFNB and portable infusion pump as early as postoperative day three. Patients given four days of perineural ropivacaine attained all three criteria in a median (25th–75th percentiles) of 47 (29–69) hours, compared with 62 (45–79) hours for those of the control group (Estimated ratio=0.80, 95% confidence interval: 0.66–1.00; p=0.028). Compared with controls, patients randomized to ropivacaine met the discharge criterion for analgesia in 20 (0–38) vs. 38 (15–64) hours (p=0.009), and intravenous opioid independence in 21 (0–37) vs. 33 (11–50) hours (p=0.061). We conclude that a four-day ambulatory cFNB decreases the time to reach three important discharge criteria by an estimated 20% following TKA compared with an overnight cFNB, primarily by improving analgesia.

Local infiltration analgesia (LIA) is an analgesic technique that has gained popularity since it was first brought to widespread attention by Kerr and Kohan in 2008. The technique involves the infiltration of a large volume dilute solution of a long-acting local anesthetic agent, often with adjuvants (e.g., epinephrine, ketorolac, an opioid), throughout the wound at the time of surgery. The analgesic effect duration can then be prolonged by the placement of a catheter to the surgical site for postoperative administration of further local anesthetic. The technique has been adopted for use for postoperative analgesia following a range of surgical procedures (orthopedic, general, gynecological, and breast surgeries). The primary objective of this paper was to determine, based on the current evidence, if LIA is superior when compared to no intervention, placebo, and alternative analgesic methods in patients following total hip arthroplasty, in terms of certain outcome measures. The outcomes considered were postoperative analgesia scores, joint function/rehabilitation, and length of hospital stay. Secondary objectives were to review available evidence and current knowledge regarding the pharmacokinetics of local anesthetic and adjuvant drugs when administered in this way and the occurrence of adverse events.

Background

We previously provided evidence that extending an overnight continuous femoral nerve block to 4 days after tricompartment knee arthroplasty (TKA) provides clear benefits during the perineural infusion in the immediate postoperative period. However, it remains unknown if the extended infusion improves subsequent health-related quality of life between 7 days and 12 months.

Methods

Patients undergoing TKA received a femoral perineural infusion of ropivacaine 0.2% from surgery until the following morning, at which time patients were randomized to either continue perineural ropivacaine (n=25) or normal saline (n=25) in a double-masked fashion. Patients were discharged with their catheter and a portable infusion pump, and catheters were removed on postoperative day 4. Health-related quality of life was measured using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index preoperatively and then at 7 days, as well as 1, 2, 3, 6, and 12 months after surgery. The WOMAC evaluates 3 dimensions of health-related quality of life: pain, stiffness and physical functional disability. For inclusion in the analysis, we required a minimum of 4 of the 6 time points, including day 7 and at least 2 of months 3, 6 and 12.

Results

The 2 treatment groups had similar WOMAC scores for the mean area under the curve calculations (point estimate for the difference in mean area under the curve for the 2 groups [overnight infusion group − extended infusion group]=1.2, 95% confidence interval: −5.6 to +8.0; p=0.72) and at all individual time points (p>0.05).

Conclusions

We found no evidence that extending an overnight continuous femoral nerve block to 4 days improves (or worsens) subsequent health-related quality of life between 7 days and 12 months after TKA. (ClinicalTrials.gov number, NCT00135889.)

Background and purpose Postoperative C-reactive protein (CRP) levels in serum appear to reflect surgical trauma. We examined CRP levels after 4 types of arthroplasty.

Material and methods We investigated 102 patients who had total knee arthroplasty (TKA), computer navigation-assisted total knee arthroplasty (NAV-TKA), hip resurfacing arthroplasty (metal on metal, MMSA) and total hip arthroplasty (THA), respectively. CRP levels were estimated before surgery and postoperatively at 2 and 7 days.

Results Postoperatively, the peak CRP levels were highest on the second day after surgery in each of the groups. The peak CPR levels after hip resurfacing were lower than those after conventional primary THA. The peak CRP levels after computer navigation-assisted TKA were lower than those after conventional primary TKA.

Interpretation The extent of bone and bone marrow injury rather than the region of surgery or the amount of soft tissue damage appears to determine the extent of the postoperative CRP response.

Introduction

The aim of this study was to compare the postoperative analgesic efficacy of epidural ropivacaine 0.15%, levobupivacaine 0.15% and ropivacaine 0.15% plus fentanyl 2 µg/ml, used with a patient-controlled epidural analgesia (PCEA) device after Caesarean section.

Material and methods

Sixty women undergoing elective Caesarean section under combined spinal-epidural anaesthesia were enrolled. Postoperatively, patients received PCEA with either ropivacaine or levobupivacaine 0.15% (basal rate 6 ml/h, bolus 5 ml/20 min), or ropivacaine 0.15% plus fentanyl 2 µg/ml (basal rate 6 ml/h, bolus 4 ml/20 min). Sympathetic and sensory level of analgesia, motor ability (Bromage 0-3), and pain scores at rest, movement and cough (VAS 0-10), haemodynamic parameters, oxygenation, side effects and total doses of local anaesthetic were documented every 6 h for 24 h. Patient satisfaction was assessed using a descriptive scale.

Results

No significant difference was observed in pain scores at all time intervals. A significantly higher sympathetic and sensory blockade occurred with levobupivacaine and ropivacaine 0.15% compared to ropivacaine 0.15% plus fentanyl, with no significant difference in total local analgesic consumption at 24 h (p = 0.08). Rescue analgesic requirements did not differ between the groups (p = 0.8) while patients’ satisfaction was significantly higher in the ropivacaine 0.15% plus fentanyl group (p = 0.02). Haemodynamics, oxygenation, nausea, pruritus and numbness did not differ between the groups.

Conclusions

Dilute local anaesthetic solutions provided satisfactory postoperative analgesia after Caesarean section when used with a PCEA device. The combination of ropivacaine 0.15% with fentanyl 2 µg/ml appeared superior, since it provided higher patient satisfaction with statistically equal pain scores and local anaesthetic consumption.

The effect of closed-suction drainage with red-cell reinfusion on patients receiving low molecular weight heparin (LMWH) prophylaxis after total knee arthroplasty (TKA) has not been previously studied. Therefore, our goals were to determine the effect of reinfusion drains and LMWH on allogeneic transfusions and wound complications after TKA by comparing patients treated with and without drains. Overall, transfusion rates were lower in the drain group (40% vs 15%, P=.04). Patients with reinfusion drains had a significantly higher rate of allogeneic transfusion (15.8%) than those predonating autologous blood and no drain (5.4%, P=.0003). The drain group had lower rates of wound complications (P=not significant). We were unable to demonstrate the efficacy of red-cell reinfusion as a substitute for autologous donation in TKA.

Background and Objectives:

It is currently unknown if the primary determinant of continuous peripheral nerve block effects is simply total drug dose, or whether local anesthetic concentration and/or volume have an influence. We therefore tested the null hypothesis that providing ropivacaine at different concentrations and rates—but at an equal total basal dose—produces similar effects when used in a continuous interscalene nerve block.

Methods:

Preoperatively, an interscalene perineural catheter was inserted using the anteriolateral approach in patients undergoing moderately painful shoulder surgery. Subjects were randomly assigned to receive a postoperative perineural infusion of either 0.2% ropivacaine (basal 8 mL/h, bolus 4 mL) or 0.4% ropivacaine (basal 4 mL/h, bolus 2 mL) through the second postoperative day. Our primary end point was the incidence of an insensate hand/finger during the 24-hours beginning the morning following surgery.

Results:

The incidence of an insensate hand/finger did not differ between the treatment groups (n=50) to a statistically significant degree (0.2% ropivacaine mean [SD] of 0.8 [1.3] times; 0.4% ropivacaine mean 0.3 [0.6] times; estimated difference=0.5 episodes, 95% confidence interval, −0.1 to 1.1 episodes; p=0.080). However, this is statistically inconclusive given the confidence interval. In contrast, pain (p=0.020) and dissatisfaction (p=0.011) were greater in patients given 0.4% ropivacaine.

Conclusions:

For continuous interscalene nerve blocks, the 95% confidence interval (plausible differences in the incidence of an insensate hand/finger) contains values ranging from a clinically important disadvantage (1.1) to a clinically unimportant advantage (−0.1) for the lower concentration. Given the statistically inconclusive results and design limitations of the current study, further research on this issue is warranted. In contrast, providing a lower concentration of local anesthetic at a higher basal rate provided superior analgesia. These relationships are different than previously reported for continuous popliteal-sciatic nerve blocks. The interaction between local anesthetic concentration and volume is thus complex and varies among catheter locations.

Background

Postoperative pain control is a challenge in patients undergoing TKA due to side effects and technical limitations of current analgesic approaches. Local anesthetic infiltration through continuous infusion pumps has been shown to reduce postoperative pain in previous studies.

Questions/purposes

We assessed the effectiveness of intraarticular ropivacaine infusions in reducing pain and postoperative opioid use after TKA and determined whether such infusions accelerate functional recovery of the patient and reduce length of hospital stay.

Methods

In a randomized, prospective, double-blind study, two groups were assigned: Group A (n = 25) underwent continuous intraarticular infusion with 300 mL ropivacaine 0.2% at a speed of 5 mL/hour through an elastomeric infusion pump and Group B (n = 25) had an elastomeric pump insertion with 300 mL saline solution at an infusion speed of 5 mL/hour. All patients had the same prosthesis model implanted. Parameters analyzed over the first 3 days, at discharge, and 1 month later included postoperative pain, joint function, opioid use, and length of hospital stay.

Results

All patients in Group A showed a decrease in pain intensity measured by a visual analog scale and opioid use in the first 3 days. Mean length of hospital stay was also reduced in Group A (5.72 days) compared to Group B (7.32 days). There were no device-related complications.

Conclusions

Use of an infusion pump is effective in treating pain after TKA, reducing postoperative pain and opioid use. It also improves immediate functionality and patient comfort, reducing the mean length of hospital stay, without increasing the risk of complications.

Level of Evidence

Level I, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Background

The authors tested the hypotheses that after hip arthroplasty, ambulation distance is increased and the time required to reach three specific readiness-for-discharge criteria is shorter with a 4-day ambulatory continuous lumbar plexus block (cLPB) than with an overnight cLPB.

Methods

A cLPB consisting of 0.2% ropivacaine was provided from surgery until the following morning. Patients were then randomly assigned either to continue ropivacaine or to be switched to normal saline. Primary endpoints included (1) time to attain three discharge criteria (adequate analgesia, independence from intravenous analgesics, and ambulation ≥ 30 m) and (2) ambulatory distance in 6 min the afternoon after surgery. Patients were discharged with their cLPB and a portable infusion pump, and catheters were removed on the fourth postoperative day.

Results

Patients given 4 days of perineural ropivacaine (n = 24) attained all three discharge criteria in a median (25th-75th percentiles) of 29 (24-45) h, compared with 51 (42-73) h for those of the control group (n = 23; estimated ratio = 0.62; 95% confidence interval, 0.45-0.92;P = 0.011). Patients assigned to receive ropivacaine ambulated a median of 34 (9-55) m the afternoon after surgery, compared with 20 (6-46) m for those receiving normal saline (estimated ratio = 1.3; 95% confidence interval, 0.6-3.0;P = 0.42). Three falls occurred in subjects receiving ropivacaine (13%),versusnone in subjects receiving normal saline.

Conclusions

Compared with an overnight cLPB, a 4-day ambulatory cLPB decreases the time to reach three predefined discharge criteria by an estimated 38% after hip arthroplasty. However, the extended infusion did not increase ambulation distance to a statistically significant degree.

After total knee arthroplasty (TKA) the technique of wound management is not standardised. In this prospective study the efficacy of autologous blood reinfusion from the wound was investigated. One hundred patients (100 TKAs) were enrolled in this sequential cohort study. In one-half of the operations, a reinfusion system with suction and in the other half one wound drain without suction were used. Blood loss, transfusion requirements, range of motion, Insall scores and the incidence of complications were studied. The use of a reinfusion system did not decrease the homologous transfusion requirements. The blood loss in the group with a suction drainage system was significantly higher. Our experiences since May 2002 with one drain without suction in 787 consecutive TKAs confirm all findings of the current study.