Antibiotics and Open Fractures of the Lower Extremity: Less Is More

SLR - March 2018 - Devon W. Consul

Reference: Bankhead-Kendall B, Gutierrez T, Murry J, Holland D, Agrawal V, Almahmoud K, Pearcy C, Truitt MS. Eur Antibiotics and Open Fractures of the Lower Extremity: Less Is More J Trauma Emerg Surg. 2017 Dec 16. doi: 10.1007/s00068-017-0847-x.

Scientific Literature Review

Reviewed By: Devon W. Consul, DPM
Residency Program: Grant Medical Center, Columbus, OH

Podiatric Relevance: Infectious complications in open lower-extremity fractures contribute to significant morbidity. Historically, orthopaedic guidelines have recommended that Grade III fractures receive a first-generation cephalosporin and an aminoglycoside. Despite these guidelines, few studies have evaluated the utility of adding an aminoglycoside in this patient population. Grade III open fractures were either treated with a cephalosporin alone or cephalosporin with aminoglycoside. The hypothesis was that outcomes were the same between the two groups.

Methods: IRB approved retrospective review of all patients 18 years of age and older, with Grade III fractures of the lower extremity conducted from 2010 to 2015. The Gustilo and Anderson classification was used to classify all fractures. Patients were divided into two groups: patients treated with cephalosporin alone and patients treated with a cephalosporin and an aminoglycoside in combination. Patient demographics, injury specific parameters, including mechanism of injury, grade of fracture, type of antibiotic administered, incidence of acute kidney injury, surgical site infection, hardware removal, hospital length of stay and disposition, were recorded. Acute kidney injury was defined using the risk, injury and failure; and loss; and end-stage kidney disease criteria as either a GFR decrease by 50 percent or a twofold increase of serum creatinine.
 

Results: Over the five-year study period, 126 Grade III fractures of the lower extremity were admitted. Overall, patient demographics consisted of age (47 ± 20 years), sex (68 percent male versus 32 percent female) and ethnicity. The mechanism of injury consisted of (88 percent blunt versus 12 percent penetrative) and causes of injury (57 percent MVC, 26 percent falls, 12 percent ballistics and 5 percent other). The injury severity score was (12 ± 10), and hospital length of stay was (10 ± 10 days). In the patient population, there were 65 (52 percent) patients in the CEPH group and 61 (48 percent) in CEPH+AG group. The mean duration of antibiotic administration between the two groups was not different (CEPH 66 hours versus CEPH+AG 72 hours).

The cohorts did not differ in the incidence of other orthopaedic injuries in addition to the open fracture (CEPH 48 percent, CEPH + AG 44 percent) or in the surgical interventions employed in the treatment of their injuries. Clinical parameters demonstrated no difference in the incidence of infection, infectious-related hardware removal, HLOS or ultimate disposition. In addition, there was no difference in mean baseline serum creatinine levels between the two groups (CEPH 1.12 mg/dL vs CEPH+AG 0.98 mg/ dL). Although, patients in CEPH had a 4 percent incidence of AKI, while the incidence was 10 percent of patients in CEPH+AG.

Conclusions: In the landmark study from 1984, Gustilo reported that 77 percent of cultures isolated from open fractures were of Gram-negative bacteria. The conclusion was then made to advocate for the usage of aminoglycosides in high-grade injuries, although there was lacking evidence in support of this practice. This study demonstrated that the addition of an aminoglycoside was associated with a significant increase in AKI with no change in the incidence of wound infection or hardware removal. Therefore, cephalosporins alone may be sufficient for prophylaxis in Grade III open fractures of the lower extremity.