High volume infiltration with local anaesthetics (LIA) during total knee arthroplasty (TKA) for postoperative pain relief may be beneficial as compared to traditional methods. Retransfusion drains are used in TKA as alternative for allogeneic blood transfusions. When combining both modalities, recollected blood may contain large doses of local anaesthetics potentially leading to systemic toxicity during retransfusion. We investigated the safety of combining LIA and retransfusion of shed blood. Twenty patients scheduled for primary TKA were included. During surgery two peri-articular injections with ropivacaine (total 375 mg) were given. Patients received an intraarticular retransfusion drain and a wound catheter for continuous infusion of ropivacaine (8 mg/hr) for 24 hours. Blood collected in the retransfusion device, was not retransfused but used for laboratory analyses. Patients’ blood samples were taken immediately after surgery, 3, 6 and 24 hours postoperatively. We predicted cumulative ropivacaine concentrations using patient and shed blood samples from 6 hours postoperatively. We modelled instant retransfusion by estimating the cumulative plasma concentrations. Our safety threshold was 0.15 mg/L unbound ropivacaine in a venous plasma sample, based on literature. Total ropivacaine concentration was highest 24 hours postoperatively and unbound ropivacaine was maximal predominantly at 6 hours. Total ropivacaine concentrations ranged from 0.7 to 1.9 mg/L and unbound ropivacaine concentrations varied between 0.03 and 0.11 mg/L. At 6 hours median shed blood volume was 600 mL (range 303–869 mL). Interestingly was the difference (mean ± SD) in free fraction ropivacaine, in shed blood (68.8–4.6%) and in plasma (4.8 ± 1.1%). Assuming retransfusion, an average 13 mg (range 6–18mg) of unbound ropivacaine would have been administered intravenously. The model used to estimate cumulative ropivacaine plasma levels showed that instant retransfusion potentially would have led to unbound venous plasma concentrations of above 0.15 mg/L. Under the conditions in our study it is safe to use LIA in combination with continuous infusion of ropivacaine. However, in combination with the retransfusion of shed blood collected with the Bellovac ABT system this may lead to toxic levels. Before implementing the combination of both modalities formal testing is required

Background. The degree of postoperative pain is usually moderate to severe following Total Hip Arthroplasty (THA). Comfort and lack of pain are important for optimal mobilization and earlier home discharge. Aim. To evaluate the efficacy and safety of Ropivacaine, a long- acting local anaesthetic, when infiltrated in the wound at the end of operation of THA. Methods. Seventy patients, 39 women and 31 men, ASA I-III, underwent Total Hip Arthroplasty in our clinic from January 2008 to June 2009. Patients were randomized into two groups. In group A, a solution of 100 ml Ropivacaine 2mg/ml (Naropeine 0,2%) was infiltrated in the deep tissues (capsule, gluteus medius, gluteus maximus and rotators) (50 ml) while the fascia, subcutaneous tissues and skin were infiltrated with the remaining 50ml. Group B was the control group. All patients received standardized general anesthesia or spinal anesthesia and a PCA morphine using a self-administered pain pump was applied in the recovery room for 48 hours. All patients took 1gr x 3 Apotel i.v., 40mg x2 Dynastat i.v., and 4mg x2 Zofron i.v. for 48 hours postoperative. Pain scores with Visual Analogue Scale (0–10) at 1, 2, 4, 8, 12, 24 and 48 hours postoperatively, time to the first analgesic requirement and side effects were recorded. Results. There were no significant differences in demographic characteristics of the patients and duration of the surgery between two groups. Morphine consumption was statistically significantly lower in group A for the first 48 hours, resulting in a lower frequency of nausea, itching and sedation. Postoperative pain levels at rest and during mobilization were statistically significantly lower in group A while median hospital stay was similar in both groups. Conclusion. Operative wound infiltration with ropivacaine reduces pain and the requirement for analgesics after hip replacement, leading to faster postoperative mobilization

Patients undergoing total knee arthroplasty (TKA) experience significant postoperative pain. This impedes early mobilization and delays hospital discharge. A prospective audit of 1081 patients undergoing primary TKA during 2008 was completed. All patients followed a programme including preoperative patient education, pre-emptive analgesia, spinal/epidural anaesthesia with propofol sedation, intra-articular soft tissue wound infiltration, postoperative high volume ropivacaine boluses with an intra-articular catheter and early mobilization. Primary outcome measure was length of stay. Secondary outcomes were verbal analogue pain scores on movement, time to mobilization, nausea and vomiting scores, urinary catheterization for retention, need for rescue analgesia, range of motion at discharge and six weeks postoperatively. The median day of discharge was postoperative day four. Median pain score on mobilization was three for first postoperative night, day one and two. 35% of patients ambulated on the day of surgery and 95% of patients within 24 hours. 79% patients experienced no nausea or vomiting. Catheterization rate was 6.9%. Rescue analgesia was required in 5% of cases. The median day of discharge was postoperative day four. Median range of motion was 85° on discharge and 93° at six weeks postoperatively. This comprehensive care plan provides satisfactory postoperative analgesia allowing early safe ambulation and discharge