Yoeri Bemelmans

Local infiltration analgesia in knee arthroplasty 49 4 Operative and analgesia treatment According to a standardized pain protocol (Table 1), patients received premedication 2 h before operation. Patients were operated under spinal or general anaes-thetic treatment by a single experienced knee arthroplasty surgeon (NK) with the use of patient-specific positioning instruments (Signature™, Biomet, Warsaw IN) for TKA. All patients received a cemented Vanguard™ Complete Knee System. (Biomet, Inc, Warsaw, IN) A pneumatic tourniquet was positioned on the thigh before surgery and inf lated to 350 mmHg during cementing. Single-shot LIA was injected by the orthopaedic surgeon (NK), intra-oper-atively according to Kerr and Kohan [19]. Mean operation time (incision to closure in minutes) and mean blood loss (total volume of blood in the suction device prior to rins-ing the knee with pulse lavage system in millilitres) were recorded in the patients’ operative records. Patients did not receive an intra-articular catheter, nor postoperative injec-tions with analgesia nor a drain or urinary catheter. Urinary retention was tested with the use of a bladder scan (Vera-thon®, BVI 9400). Pre- and postoperative patients received a multimodal opioid sparing pain protocol (Table 1). Daily thromboprophylaxis (Fondaparinux) was administered sub-cutaneously once each evening for 35 days, starting on the day of surgery. Compression bandage was removed <24 h. On day one postoperative patients received analgesics in the morning (Table 1) and daily four times paracetamol (1 g). If analgesics were ineffective on the day of surgery or the first or second day postoperative, rescue analgesia (Tramadol, 100 mg) once daily was provided on demand. From day two till day 14 postoperative, patients received analgesics according to a multimodal opioid sparing pain protocol (Table 1). Study endpoints Experienced pain was measured with a visual analogue scale (VAS; 0 to 100, 100 being ‘worst pain’). Pain was measured before and after the first mobilization and dur-ing the first 48 h postoperative on fixed time points (direct postoperative, and daily 8:00, 16:00 and on 22:00 h). Res-cue medication use was evaluated, the amount of patients who used postoperative Tramadol were registered. Early mobilization (minutes) was recorded as time between the start of anaesthesia until the first mobilization. Length of hospital stay (days) was evaluated as time between hospi-tal admission and discharge. Adverse events (AE’s) were classified as patient related [e.g. postoperative nausea and vomiting (PONV)], thromboembolic events and wound dis-orders (e.g. persistent wound leakage), surgical related (e.g. infection) and/or prosthesis related (e.g. loosening). Pain, PONV and discharge criteria were evaluated daily on fixed time points (8:00, 16:00 and on 22:00 h). Besides the dif-ference of the LIA mixture, pre-, peri- and postoperative procedures and pain protocol were identical in both groups as well as the completed operative and clinical case report