Assessment of the effectiveness of weight-adjusted antibiotic administration,for reduced duration,in surgical prophylaxis of primary hip and knee arthroplasty

BACKGROUND Prophylactic antibiotics have significantly led to a reduction in the risk of postoperative surgical site infections(SSI)in orthopaedic surgery.The aim of using antibiotics for this purpose is to achieve serum and tissue drug levels that exceed,for the duration of the operation,the minimum inhibitory concentration of the likely organisms that are encountered.Prophylactic antibiotics reduce the rate of SSIs in lower limb arthroplasty from between 4%and 8%to between 1%and 3%.Controversy,however,still surrounds the optimal frequency and dosing of antibiotic administration.AIM To evaluate the impact of introduction of a weight-adjusted antibiotic prophylaxis regime,combined with a reduction in the duration of administration of post-operative antibiotics on SSI incidence during the 2 years following primary elective total hip and knee arthroplasty METHODS Following ethical approval,patients undergoing primary total hip arthroplasty(THA)/total knee arthroplasty(TKA)with the old regime(OR)of a preoperative dose[cefazolin 2 g intravenously(IV)],and two subsequent doses(2 h and 8 h),were compared to those after a change to a new regime(NR)of a weight-adjusted preoperative dose(cefazolin 2 g IV for patients<120 kg;cefazolin 3g IV for patients>120 kg)and a post-operative dose at 2 h.The primary outcome in both groups was SSI rates during the 2 years post-operatively.RESULTS A total of n=1273 operations(THA n=534,TKA n=739)were performed in n=1264 patients.There was no statistically significant difference in the rate of deep(OR 0.74%(5/675)vs NR 0.50%(3/598);fishers exact test P=0.72),nor superficial SSIs(OR 2.07%(14/675)vs NR 1.50%(9/598);chi-squared test P=0.44)at 2 years postoperatively.With propensity score weighting and an interrupted time series analysis,there was also no difference in SSI rates between both groups[RR 0.88(95%CI 0.61 to 1.30)P=0.46].CONCLUSION A weight-adjusted regime,with a reduction in number of post-operative doses had no adverse impact on SSI incidence in this population.

Effect of weight-adjusted antimicrobial antibiotic prophylaxis on postoperative dosage and surgical site infection incidence in total joint arthroplasty

Surgical site infections(SSI)following total joint arthroplasty pose a significant concern for both providers and patients across the globe.Currently,administration of antimicrobial antibiotic prophylaxis is used throughout the world to reduce the incidence of SSI.However,the correct dosage and frequency of administration remains debatable.In this editorial,we emphasized the determination of the effect of administration of weight-adjusted antimicrobial antibiotic prophylaxis regime on the incidence of SSI and postoperative dosage reduction compared to the conventionally used regime during total joint arthroplasty.The results demonstrated similar efficacy between both regimes with respect to the incidence of SSI.In addition,weight-adjustment led to reduced postoperative dosage and has the potential to reduce chances of achieving lower therapeutic concentration,drug resistance,drug toxicity,and costs.