What is the most common cause of post-operative deep infections in total hip replacement: airborne bacteria in the operating room, post-operative wound contamination, intra-operative sepsis (septicaemia), contaminated acrylic cement, or inappropriate antibiotic coverage?

From the Research

The most common cause of post-operative deep infections in total hip replacement is airborne bacteria in the operating room. These infections typically occur when airborne microorganisms, particularly Staphylococcus species, contaminate the surgical site during the procedure 1. Despite modern operating room ventilation systems and strict sterile protocols, microscopic bacteria suspended in the air can settle onto exposed tissues, implants, or surgical instruments. The risk is heightened during total hip replacement due to the relatively long duration of the procedure and the large surgical exposure required. This is why laminar flow operating rooms, body exhaust suits, and ultraviolet light systems have been developed to reduce airborne contamination. Additionally, perioperative antibiotics are administered to help prevent these infections, typically starting just before incision and continuing for 24 hours post-operatively.

Some key factors that contribute to the risk of deep infection include:

• Concurrent urinary tract infection 1
• Increasing delay to theatre for treatment of the fracture 1
• The use of cemented arthroplasty, which may be protective 1
• The type of organism involved, with gram-negative organisms reducing success rates of treatment 1

While other factors like post-operative wound contamination can contribute to infections, airborne contamination during the procedure itself remains the predominant source of deep prosthetic joint infections. The most recent and highest quality study 1 suggests that deep infection remains a devastating complication regardless of the treatment strategy employed, with success rates of debridement, antibiotic, and implant retention (DAIR) being poor compared to total hip arthroplasty.

It is essential to focus on preventing these infections by employing strategies such as timely administration of antibiotic prophylaxis 2, using antibiotic-impregnated cement 3, and reducing airborne contamination in the operating room. By prioritizing these measures, we can minimize the risk of post-operative deep infections in total hip replacement and improve patient outcomes in terms of morbidity, mortality, and quality of life.