Page 857 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

588 PART 5: Infectious Disorders

CHAPTER Infectious Complications including local site infection, bacteremia, clinical sepsis without bacte-
remia, line fracture and extravasation of fluids or drugs, obstruction by
66 of Intravascular Access medication, thrombosis, thrombophlebitis, and septic thrombophlebitis.
Infectious complications are the most frequent and among the most
Devices Used in Critical Care serious of these complications. The magnitude of CVC-related infec-
tious complications can be appreciated when one realizes there are an
John Conly estimated 15 million days of exposure to CVCs in patients in ICUs in
the United States each year with 80,000 cases of central line–associated
blood stream infections (CLABSI) annually. Catheter-related infections
1
KEY POINTS are associated with significant morbidity and mortality with attributable
• Intravascular access device–associated infections may be either length of stay extended between 7 and 19.1 days and attributable mortal-
local or bacteremic, and the risk of developing an infection varies ity reported as high as 24.6% to 35%. 1-4
with the patient population, the type of device, the microbe, and
the patient-microbe-device interaction. EPIDEMIOLOGY
• The status of all indwelling vascular access devices should be The risk of developing device-related infection (either local or bacteremic)
reviewed daily by the critical care team, with attention to the dura- varies between ICUs and countries depending on the patient population,
tion of placement, appearance of the exit site, and continued clini- the type of device and its intended use, the microorganisms involved, and
cal indication for the intravascular device. the patient-microbe-device interaction. The annual National Healthcare
• Central venous catheters account for over 90% of all intravascular Safety Network in the US reports stratify CLABSIs per ICU type and
device–related bacteremias. representative incidence-density rates are shown from its most recent
5
• Most intravascular device–related bacteremias are caused by publication in Table 66-1. Representative rates from other types of cath-
7,8
6
endogenous skin flora at the catheter insertion site that migrate eters are also provided. The risk factors for device-associated infection
along the transcutaneous portion of the catheter with subsequent that have been identified for the host, the microbe, the device, and the
colonization of the catheter tip. interactions among them are listed in Table 66-2.
• Coagulase-negative staphylococci and Staphylococcus aureus Of the many intravascular devices available, the peripheral venous
account for just over 50% of all intravascular device–related bacte- catheter is by far the most commonly used. Most peripheral
venous catheters currently are made of polyurethane or steel and are
remias, followed in frequency by gram-negative bacilli and yeast. associated with a very low risk of bacteremia, with less than one episode
• Diagnosis of intravascular device–related infection, either local or of bacteremia per 500 devices. There is little difference currently in the
7,8
bacteremic, is best approached using a combination of clinical and risk of bacteremia regardless of whether polyurethane or steel needles
laboratory criteria. are used if the same level of asepsis is applied at the time of placement.
• Although treatment of central-line infections due to coagulase- Peripheral arterial catheters are in widespread use in ICUs for blood
negative staphylococci may be successful without catheter removal, pressure monitoring and for obtaining arterial samples for blood gas
infections caused by S aureus necessitate catheter removal. determination. The incidence of bacteremia related to peripheral arterial
6,9
• Central intravascular catheter infections are essentially prevent- devices is about 1.7/1000 catheter-days and the rate of significant colo-
able infections. Successful prevention entails attention to a careful nization (≥15 colony-forming units [cfu] on semiquantitative culture)
9,10
needs assessment for the device, careful site selection, maximal is about 5%. Insertion by cutdown, catheterization lasting 4 days or
barrier precautions and sterile technique on insertion, insertion longer, and inflammation at the catheter exit site are associated with a
by the most skilled operators, rigorous catheter-site care, and inter- higher risk of significant catheter colonization.
rupting the integrity of the system as little as possible. CVCs are estimated to account for over 90% of all catheter-related
bacteremias. Prospective studies of noncuffed, short-term single or

The use of intravascular access devices has become an integral part TABLE 66-1 Representative Rates for Intravascular Device-Associated Bacteremia
of modern patient care, and nowhere is this more evident than the
intensive care unit (ICU). Over the years, an increasing array of devices Type of Device Setting Incidence Density Rate
other than the original peripheral and single-lumen central catheters Peripheral
have been introduced. There is currently no standardized nomenclature Short-term, infusion lock Med-surg wards 0.5/1000 catheter-days
for vascular access devices and they may be differentiated based on the
number of lumens, site of insertion, use of cuffs or tunneling, category, Midline Med-surg wards 0.2/1000 catheter-days
or even by name. From a generic perspective they may be classified as Arterial Med-surg ICU 1.7/1000 catheter-days
percutaneously inserted peripheral or central lines and totally implant- PICC Out/inpatient 1.0 -2.1/1000 catheter-days
able devices. Central lines may be further distinguished as tunneled or
nontunneled and noncuffed or cuffed. The most frequently encountered Central
devices are single lumen peripheral lines, noncuffed, nontunneled mul- Non-cuffed venous Medical ICU 2.0-2.6/1000 catheter-days
tilumen central venous catheters (CVCs), tunneled and cuffed CVCs, (single- or multilumen) CCU 2.0/1000 catheter-days
flow-directed pulmonary artery catheters (PACs), peripherally inserted
central and midline catheters, peripheral arterial catheters, and implant- Surgical ICU 2.0-2.6/1000 catheter-days
able devices. Intraosseous vascular access lines may occasionally be Trauma 3.6/1000 catheter-days
encountered. Pediatric ICU 1.3-3.3/1000 catheter-days
These intravascular access devices provide a route for the adminis-
tration for fluids, blood products, nutritional products, and medica- Burn units 5.50/1000 catheter-days
tions; allow the monitoring of hemodynamic functions; and permit Cuffed venous (Hickman, Hematology-oncology 1.7/1000 catheter-days
bloodletting and the maintenance of emergency access. However, vas- Broviac) wards
cular access devices may be associated with several complications, CCU, coronary care unit; ICU, intensive care unit; PICC, peripherally inserted central catheter.

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