Surgeons performing revision shoulder arthroplasty typically order postoperative antibiotics to be administered while they wait for results from intraoperative cultures. Based on their index of suspicion from preoperative exams and intraoperative observations, they order either intravenous (high suspicion of infection) or oral (low suspicion) antibiotics during the waiting period. In the June 3, 2020 issue of JBJS, Yao et al. report on a retrospective review of 175 patients who underwent revision shoulder arthroplasty, finding that surgeons’ presumptive choice of antibiotic type matched the culture results in 75% of the cases.
Among the 175 patients in the study, IV antibiotics were initiated in 62, while 113 patients received oral antibiotics. Cultures from 49 of the 62 patients started on IV antibiotics came back positive, and cultures from 83 of the 113 patients started on oral antibiotics came back negative. Treatment of patients whose initial antibiotic regimen did not match culture results was modified accordingly.
After multivariate analysis Yao et al. found that male sex, prior ipsilateral infection, and intraoperative presence of a humeral membrane were 3 independent predictors of surgeons initiating IV antibiotics. Antibiotic-related adverse events (including GI, dermatologic, and allergic reactions) occurred in 19% of the patients. Not surprisingly, the rate of these complications was highest among those receiving IV antibiotics.
Although the surgeons’ empirical initiation of antibiotic administration route was “correct” 75% of the time, that still left 25% of the patients needing modification of therapy based on culture results. While the authors observe that their study was not designed “to report the relative effectiveness of the 2 antibiotic protocols in minimizing the risk of recurrent infection,” their findings confirm that preoperative and intraoperative observations can help surgeons select the “right” type of antibiotic without culture results—and that is heartening.
Along the spectrum of early and late adopters in medicine, most orthopaedic surgeons fall in the middle. They wait for science to prove the efficacy and safety of an innovation, carefully review the published studies regarding that innovation, and adopt it if it will improve their patients’ outcomes.
In the December 4, 2019 issue of JBJS, Jules-Elysee et al. compare tranexamic acid (TXA) administered intravenously (IV) versus topically in a double-blinded, randomized controlled trial (RCT) of patients undergoing primary total knee arthroplasty (TKA). Level-I evidence is rare in the orthopaedic literature, so when a well-performed RCT comes out, we should closely evaluate its findings.
A potent antifibrinolytic, TXA has been shown in multiple studies to decrease blood loss associated with major orthopaedic procedures. However, there are persistent (but not necessarily evidence-based) concerns about its potential to cause thrombogenic complications, and the safest and most effective route of TXA administration remains an open question.
In this study, the IV group received TXA once before tourniquet inflation and again 3 hours later, along with a topical placebo given 5 minutes before tourniquet release. The topical group received an IV placebo at the same time intervals as the IV group, along with TXA delivered topically in the wound prior to tourniquet release. The authors found lower systemic levels of plasmin-anti-plasmin (PAP, a measure of fibrinolysis) in both groups 1 hour after tourniquet release, but PAP levels remained significantly lower in the IV group (indicating higher antifibrinolytic activity) 4 hours after tourniquet release, which was likely related to the second IV dose of TXA.
The authors also found no between-group difference in systemic or wound levels of prothrombin fragment 1.2 (PF1.2, a marker of thrombin generation), indicating there was no increase in thrombogenicity in the IV group. Interestingly, Jules-Elysee also found that the IV group had significantly higher hemoglobin and hematocrit levels 1 and 2 days after surgery, and those patients had a significantly shorter hospital stay.
Finding no major between-group differences in the mechanism of action, coagulation, or fibrinolytic profile, the authors concluded that a single IV dose of TXA may be the most simple protocol for hospitals to adopt if they are still concerned about TXA safety. Perhaps these Level-I findings will help some of the late adopters get over their fears about the safety of IV TXA.
Matthew R. Schmitz, MD
JBJS Deputy Editor for Social Media
OrthoBuzz occasionally receives posts from guest bloggers. In response to a recent New England Journal of Medicine study, the following commentary comes from Daniel Leas, MD and Joseph R. Hsu, MD.
Deep infections continue to be one of the most resource-intensive problems that orthopaedic surgeons face. Long-standing dogma has favored 6 or more weeks of intravenous (IV) antibiotics, resulting in increased healthcare costs during both the inpatient and outpatient treatment periods.
To explore the possibility of utilizing targeted oral antibiotics as an alternative, effective treatment for musculoskeletal infections, the OVIVA (Oral versus Intravenous Antibiotics) multicenter research collaboration conducted a prospective, randomized controlled trial. A total of 1,054 patients with deep musculoskeletal infections were randomized to oral or IV arms for 6 weeks of antibiotic treatment and followed for 1 year to determine treatment efficacy. The primary end point was treatment failure within 1 year, defined as the presence of predefined clinical symptoms of deep infection, microbiologic evidence of continued infection, or histologic presence of microorganisms or inflammatory tissue. Secondary outcomes included catheter-associated complications, discontinuation of therapy, and Clostridium difficile diarrhea.
Of the 1,054 patients enrolled, 909 patients were included in the final analysis. Treatment failure occurred in 14.6% of patients treated with IV antibiotics and 13.2% of patients in the oral-therapy group. This -1.4% difference indicated noninferiority based on the predetermined 7.5% noninferiority margin. Secondary outcomes between the groups differed only in catheter-related complications being more common in the IV group (9.4% vs 1.0% in the oral group).
These findings and conclusions should challenge us to re-evaluate the basis for extended IV antibiotics to treat complex musculoskeletal infections, and to consider a greater role for oral antibiotics for such infections. Further study of this question focused on patients with retained hardware is warranted.
Daniel P. Leas, MD is a PGY-5 orthopaedic resident at Carolinas Medical Center.
Joseph R. Hsu, MD is a Professor of Orthopaedic Trauma and Vice Chair of Quality at the Atrium Health Musculoskeletal Institute.