Bacterial growth on suction drain tips. Prospective study of 489 clean orthopedic operations

The study included 489 clean orthopedic operations with implantation of major foreign materials (joint replacements and internal fixations of fractures). Specimens for culture were taken from the suction drainage system, either from the drain fluid or from the drain-tube tip or from both. Six superficial and five deep infections were seen following the operations. Only two cultures of drain fluid were positive, and neither of these became infected. Positive drain-tip cultures were seen after 56 operations, and of these, five were followed by infection. The risk of infection was increased if Staphylococcus aureus, Enterobacteriaceae, or Streptococcus faecalis was cultured from drain tips. Drain-tip cultures growing only coagulase-negative staphylococci, nonhemolytic streptococci, and corynebacteria were not correlated with increased risk of infection. There was a not significant tendency towards fewer infections if positive drain-tip cultures with virulent bacteria were treated with specific antibiotics.