ICU Corner
AHRQ
The Agency for Healthcare Research and Quality (AHRQ) published the important evidence-based report “Making Health Care Safer: A Critical Analysis of Patient Safety Practices.”1 This review summarizes one of the top 11 recommendations: the use of a total body drape during insertion of central venous catheters. A total body drape is believed to be an important intervention to prevent intravascular catheter-associated infections.
Catheter-Associated Infections
Infections associated with indwelling central venous catheters are relatively common. The Center for Disease Control and Prevention (CDC) estimates that the rate of such infections is 4.5-6.1 per 1,000 catheter-days for patients being cared for in medical-surgical intensive care units. In aggregate, this accounts for approximately 200,000 bloodstream infections per year in the United States. Infection with organisms such as gram-negative rods, staphylococci, and even Candida may account for an associated mortality of 25% (attributable to the catheter-related infection itself). The most important pathophysiologic mechanisms of these infections include the skin insertion site (as a portal of entry), as well as breaks in sterility at the catheter hub. It is relatively uncommon for catheters to become infected from hematogenous spread of organisms or from contaminated solutions infusing through the catheter. Current efforts to minimize infectious problems include the routine use of antibiotic-coated catheters, thorough skin preparation with chlorhexidine gluconate, and regular use of maximal sterile barriers during the actual catheter insertion.
Maximal Sterile Barriers
Simple, but effective! Many catheter infections actually result from (unobserved) contamination of the introducer, central venous line, or pulmonary artery catheter during insertion. Maximal sterile barriers (MSBs) rely on the use of sterile gloves, long-sleeved sterile gowns, a non-sterile cap and mask, and a full-sized (total body) sterile drape, which covers the patient and the entire bed or operating table (see photo below). The use of an MSB does require the additional cost of the body drape and a small additional increment of time. In general, the acquisition cost of the large sterile barrier is modest, less than $10 per drape (Kimberly-Clark, Roswell, GA). While there is no obvious harm associated with use of the MSB itself, the potential benefit is quite large. One study randomized 343 patients in a large cancer hospital to two separate groups; one group used MSB, while the other utilized routine techniques consisting of sterile gloves and small sterile drapes around the immediate insertion site only.2 The authors reported a significant reduction in both the rate of catheter colonization (2.3% vs. 7.2%; p=0.04), as well as the rate of blood stream infection (p=0.02) in the MSB group. The MSB technique appears to be readily adopted by physician trainees, and in a large teaching hospital significantly reduced catheter-related infections. New house officers were instructed during a 1-day course on infection control practices and procedures, including MSB.3 Use of MSB increased significantly while the rate of catheter-related infections decreased from 4.5 infections per 1,000 days (before the course) to 2.9 infections per 1,000 catheter days one year after the course (p<0.01). This practice change was associated with an overall cost savings estimated at several hundred thousand dollars.
Summary
The AHRQ evidence-based approach is an effort to highlight appropriate clinical procedures and techniques to expedite institutional change and to promote patient safety and optimize patient care. The MSB technique reviewed above appears to be a cost-effective mechanism to reduce the incidence of catheter-related infections.
Dr. Prielipp is Section Head, Critical Care Medicine, Department of Anesthesiology, Wake Forest University Health Sciences, Winston-Salem, NC, and chair of the APSF committee on Education and Training.
References
- Making Health Care Safer: A Critical Analysis of Patient Safety Practices. AHRS Publication 01-E058. Rockville, MD: Agency of Healthcare Research and Quality, U.S. Department of Health and Human Services, 2001.
- Raad II, Hohn DC, Gilbreath BJ, et al. Prevention of central venous catheter-related infections by using maximal sterile barrier precautions during insertion. Infect Control Hosp Epidemiol 1994;15:231-238.
- Sherertz RJ, Ely EW, Westbrook DM, et al. Education of physicians-in-training can decrease the risk of vascular catheter infection. Ann Intern Med 2000;132:641-648.