Prospective study of catheter-related infection during prolonged arterial catheterization.

Ninety-six arterial catheters from 75 different anatomical sites in 56 surgical ICU patients were studied prospectively to determine the rate of catheter-related infection associated with prolonged arterial catheterization (defined as greater than 96 h). Every 96 h, all catheters were semiquantitatively (SQ) cultured and the percutaneous entry site was swab cultured. Sites were used indefinitely by exchanging the catheters over a guide-wire every 96 h as long as arterial monitoring was necessary and SQ cultures remained negative (less than or equal to 15 colonies). No sites used less than 96 h developed skin colonization, while 14/51 (27%) sites used greater than 96 h developed positive swab cultures. No SQ cultures were positive in sites with negative swab cultures (p less than .001). Catheter-related infection (a positive SQ culture) developed in 4/42 (9.5%) radial or femoral sites compared to 4/9 (44%) axillary sites used greater than 96 h (p less than .01). It is concluded that arterial catheter-related infection develops in less than 10% of radial or femoral sites used greater than 96 h, and 90% of radial and femoral sites may be used safely for prolonged periods if skin colonization at the percutaneous sites is controlled and SQ catheter cultures remain negative. Skin site swab cultures may be useful for determining when arterial catheters should be removed and SQ cultured.