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CHAPTER 27: Intravascular Devices in the ICU 183

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inferior to more frequent 3-day changes. It should be noted, however, CATHETER EXCHANGE OVER A GUIDE WIRE
that there are little data about whether antibiotic resistance emerges with In order to avoid mechanical complications of placing a new CVC, a strat-
the use of antiseptic solutions or sponges. egy of inserting a sterile guide wire through an existing catheter, removing
■ MAXIMAL STERILE BARRIERS the catheter, and inserting a new sterile CVC over the guide wire is some-
times employed. Since the existing catheter is not sterile, contamination of
Meticulous attention to sterile technique is of paramount importance the new catheter is a concern with this technique. There have been several
during the placement of CVCs. The use of maximal sterile barriers likely studies comparing scheduled catheter exchange over a guide wire and
decreases the incidence of inadvertent contamination of gloves, guide scheduled replacement of CVC at a new site every 2 days, 3 days, 7 days, or
wires, and other equipment in the CVC kit. The technique of employing as needed. In a meta-analysis, Cook and colleagues found trends toward
maximal sterile barriers, including a full body sterile drape, sterile gloves higher catheter colonization (relative risk 1.26; 95% CI 0.87-1.84), and
and long-sleeved gown, and nonsterile cap and mask has been shown to catheter-related bacteremia (relative risk 1.72; 95% CI 0.89-3.33) associ-
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reduce the incidence of CVC-related infections. Mermel and colleagues ated with exchange over a guide wire. Additionally, prophylactic catheter
found that PACs placed in the ICU with the use of maximal sterile barrier replacement was not found to reduce catheter colonization or catheter-
precautions developed fewer infections (15.1% vs 24.6%; p < 0.01) when related bacteremia as compared with replacement of the catheter on an
compared with PACs placed in the operating room without maximal as-needed basis. In fact, the CDC strongly recommends that CVC should
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sterile barrier precautions. Raad and colleagues found that the time to not be replaced nor exchanged over a guide wire on a routine basis
5
occurrence of catheter-related BSI was reduced in cancer patients who (Category 1B recommendation: Strongly recommended for implemen-
had CVCs and peripherally inserted CVCs inserted with maximal sterile tation and supported by some experimental, clinical, or epidemiologic
barriers as compared with patients who had catheters inserted with ster- studies, and a strong theoretical rationale). However, most authorities
ile gloves and a small sterile field (p < 0.05). Another study investigated recommend wire exchange for suspicion of infection or mechanical cath-
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the impact of a 1-day course taken by PGY-1 physicians on infection con- eter dysfunction. If infection is suspected, the catheter should be cultured
trol practices and hands-on instruction for several common procedures upon removal and the new catheter removed if the culture of the old
(arterial puncture, placement of arterial lines, and CVCs). Subsequently, catheter is positive (>15 CFU by the roll plate method). Catheters with
the documented use of full-size sterile drapes increased from 44% to 65% inflamed or purulent entry sites should be removed and a new catheter
and the rate of catheter-related infections decreased from 4.51 infections inserted into a different site (Fig. 27-3). 6,41
per 1000 patient-days before the first course to 2.92 infections per 1000
patient-days 18 months after the course. This decrease in catheter-related MECHANICAL COMPLICATIONS OF CENTRAL
infections was associated with an estimated cost savings of $63,000. 33 VENOUS CATHETERS
■ ANTIMICROBIAL IMPREGATED CATHETERS Lefrant and colleagues reported their experience with subclavian vein

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Another approach to reducing the incidence of catheter-related infec- catheterization over a 5-year period. A total of 707 patients in a surgi-
cal critical care unit had subclavian vein catheterization attempted, with
tions is the use of catheters treated with antimicrobial agents. Catheters 562 successful procedures (79.5%). For the remaining 145 catheterizations,
coated with chlorhexidine/silver sulfadiazine as well as minocycline/ there were 67 failed procedures (overall failure rate 9.5%). By multivariate
rifampin are currently available for clinical use. Compared with con- analysis, more than one attempted venipuncture was the only independent
ventional catheters, these antimicrobial treated catheters are associated risk factor for failed catheterization and immediate complications (arte-
with significant reductions in catheter-related bacteremia. 34,35 A study by rial puncture, pneumothorax, misplacement of catheter). Elderly patients
Maki and colleagues comparing conventional triple lumen polyurethane (age greater than 77) were more likely to have immediate complications,
catheters with catheters coated with chlorhexidine and silver sulfa- but not failed catheterization. It is noteworthy that the operator’s level of
diazine reported a reduction in both catheter colonization and nearly training and experience (junior, but not senior residents were supervised
fivefold reduction in BSI. A randomized trial of minocycline/rifampin by a critical care anesthesiologist) did not impact outcomes in the study,
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versus chlorhexidine/silver sulfadiazine catheters, however, found a suggesting that central venous catheterization can be performed safely by
significant decrease in the incidence of catheter-related BSI in the group physicians in training with adequate supervision. Based on their observa-
of patients using minocycline/rifampin (0.3 vs 3.4%; p < 0.002). There tions, the authors recommended no more than two attempts at subclavian
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are several possible reasons for the differences between the two cath- vein catheterization before aborting the procedure, with consideration
eters. The minocycline/rifampin catheters had antibacterial substances toward attempting at a different anatomical site. Contralateral attempts to
both outside and inside the catheters, as opposed to the chlorhexidine cannulate the internal jugular or subclavian vein should be preceded by a
catheters, which were only externally coated. Importantly, neither study chest radiograph to rule out pneumothorax, however, prior to proceeding.
reported hypersensitivity reactions to the catheters nor reported the
bial agents. A newer chlorhexidine/silver sulfadiazine catheter with anti- ■ ARTERIAL PUNCTURE/BLEEDING
occurrence of infections by organisms with resistance to the antimicro-
septic located on both the internal and external surfaces is now available Accidental arterial puncture is a well-recognized complication of CVC
and was shown to significantly reduce colonization rates with no signifi- placement. The incidence of this complication in published reports
cant trend toward decreased catheter-related blood stream infections. ranges from 0% to 15%. 9-11 Complications arising from accidental arterial
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A recent meta-analysis of 34 studies comparing antimicrobial impreg- puncture include mediastinal hematoma formation, hemothorax, tracheal
nated catheters suggested that chlorhexidine/silver sulfadiazine and compression and possible asphyxiation, and retroperitoneal hemorrhage.
minocycline/rifampin catheters reduce infectious complications when A meta-analysis comparing internal jugular versus subclavian catheter
compared to standard catheters. Additionally the minocycline/rifampin placement noted a higher incidence of arterial puncture with internal jugu-
catheters outperformed the first-generation chlorhexidine/silver lar catheter attempts. Although arterial puncture occurs more frequently
11
sulfadiazine catheters, and head-to-head studies for comparison of the with internal jugular attempts, the carotid artery is more readily com-
second-generation catheters are underway. However, it should be pressible compared to the subclavian artery, which makes this approach
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noted that the poor methodological quality of the studies limits inter- more attractive in patients with coagulation disturbances. Most complica-
pretation of these results. While the exact role of the catheters remains tions of accidental arterial puncture occur with dilation and subsequent
the subject of some debate, some cost-benefit analysis suggests that placement of large bore catheters into an artery. Several case reports
anti septic catheters are cost beneficial if an institution’s rate of catheter- and small series have acknowledged this important complication. 12-14
related bacteremia is three infections per 1000 catheter-days. 36 Traditional means of confirming arterial versus venous puncture of a

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