Prophylaxis In Knee Arthroplasty Research Articles

Higher cefazolin concentrations in synovial fluid with intraosseous regional prophylaxis in knee arthroplasty: a randomized controlled trial.

Prophylactic antibiotics reduce the risk of periprosthetic joint infection. However, conventional systemic administration may not provide adequate tissue concentrations against more resistant organisms such as coagulase-negative staphylococci. Intraosseous regional administration is known to achieve significantly higher antibiotic tissue concentrations than systemic administration, but it is unclear how synovial fluid concentrations are affected. We aimed to compare synovial fluid cefazolin concentrations achieved by regional intraosseous versus systemic intravenous administration, and also to compare synovial fluid cefazolin concentrations with those in subcutaneous fat. A total of 60 patients undergoing primary knee arthroplasty were randomized into 2 groups: group IO received 2g interosseous cefazolin in 100mL saline through a tibial cannula after tourniquet inflation and before skin incision; group IV received 2g cefazolin in 100mL saline via the median basilic or median cephalic vein 30min before tourniquet inflation. Subcutaneous fat and synovial fluid samples were collected immediately after skin incision, and cefazolin concentrations were measured by high-performance liquid chromatography. The cefazolin concentration in synovial fluid was 391.3 ± 70.1μg/ml in group IO and 17.6 ± 3.5μg/ml in group IV. The cefazolin concentration in subcutaneous fat was 247.9 ± 64.9μg/g in group IO and 11.4 ± 1.9μg/g in group IV. Intraosseous regional administration results in several times higher tissue concentrations than systemic administration, especially in the synovial fluid.

Allogeneic blood transfusion does not increase the risk of wound infection in total knee arthroplasty

Allogeneic blood transfusion has been reported to increase the risk of postoperative infection in arthroplasty though the results are inconclusive. Data from a previous clinical trial on antibiotic prophylaxis in knee arthroplasty were analysed to gain further insight into the relationship between wound infection and both blood transfusion and the storage time of transfused RBCs. A total of 910 consecutive patients undergoing primary knee arthroplasty were prospectively followed for 12 months after surgery. The main outcome was wound infection, either superficial or deep-tissue. Possible predictors for wound infection included the patient's age and sex, preoperative physical status, time under leg ischaemia, postoperative fluid drainage, and the number and length of storage of transfused RBCs. Deep tissue infection was diagnosed in 28 (3%) patients, superficial infection in 25 (2.7%) and cellulitis in eight (0.8%) patients. Transfusion of at least one blood unit had been given to 22 (36%) of the 61 patients who later developed wound infection and 313 (36%) of those who did not (P > 0.05). Patients who developed wound infection had a significantly poorer physical status and longer time of leg ischaemia. There was no significant difference between both groups of patients in either the amount or the length of storage of transfused RBC units. This study failed to find any association between the incidence of wound infection after knee arthroplasty and allogeneic transfusion.

Comparison of three methods of antibiotic prophylaxis in knee arthroplasty

Prophylactic intravenous cefamandole nafate was administered by the systemic, systemic with probenecid (causing renal tubular blockade of antibiotic excretion), and intravenous regional routes. Bone antibiotic levels were assayed 15 minutes and 12 hours after administration, and hematoma concentrations after 8 hours. Bone concentrations after intravenous regional administration were significantly greater than systemic after 15 minutes, but were not detectable after 12 hours. Probenecid produced inhibitory concentrations in bone after 12 hours and also increased hematoma antibiotic concentrations to three times those achieved by systemic administration. Adequate prophylaxis may be possible with two rather than three doses of cefamandole if probenecid is used.