CHAPTER 4: Infection Prevention and Surveillance in the Intensive Care Unit

KEY POINTS

• Focused surveillance for health care–associated infections is the cornerstone of infection prevention activities in the ICU.

• Commonly used invasive devices such as central venous and urinary catheters and endotracheal tubes are significant risk factors for health care–associated infection. Evidence-based ICU policies and procedures and staff education can reduce the risk of device-related infections.

• Antibiotic resistance is an increasing problem, and its containment and prevention require a multifactorial approach, including adequate hand hygiene, surveillance for resistant pathogens, enforced infection control precautions, and prudent use of antibiotics.

• Standard infection control precautions should be applied to all ICU patients. Precautions for contagious or epidemiologically significant pathogens are based on modes of transmission.

INTRODUCTION

Health care–associated infections result in significant morbidity and mortality. Health care–associated infections have been reported to affect approximately 2 million hospitalized patients in the United States annually, at an estimated cost of $57.6 billion in 2000 and approximately 100,000 deaths.^1-3 ICU beds, while only accounting for 5% to 10% of all hospital beds, are responsible for 10% to 25% of health care costs generated.⁴ Patients admitted to the ICU have been shown to be at particular risk for health care–associated infections, with a prevalence as high as 30%.⁵ Given the increasing strain on health care resources in the United States and other countries, and the personal impact that these infections have on patients, the prevention of nosocomial infections in the ICU should be an important goal of any critical care clinician.

A likely explanation to account for the observation that ICU patients are more vulnerable to acquiring a health care–associated infection compared with other hospitalized patients is that critically ill patients frequently require invasive medical devices, such as urinary catheters, central venous and arterial catheters, and endotracheal tubes. Data on a sample of ICUs from the Centers for Disease Control and Prevention (CDC) show that adult ICU patients have central venous catheters in place and receive mechanical ventilation an average of 53% and 42% of their total time spent in the ICU, respectively.⁶ These devices result in infection by compromising the normal skin and mucosal barriers and serving as a nidus for the development of biofilms, which provide a protected environment for bacteria and fungi. In a survey of cases of ICU-acquired primary bacteremia, 47% were catheter related.⁷ While the increased severity of illness of ICU patients makes intuitive sense as a potential risk factor for health care–associated infection, few studies have shown a consistent relationship.⁸ This may be explained, however, by the fact that scoring systems were developed primarily to predict mortality and may not adequately capture markers for health care–associated infection, such as the need for prolonged parenteral nutrition.

Infection control in the ICU arose from hospital-wide infection control programs developed in response to the staphylococcal pandemic of the late 1950s and early 1960s. In 1976, the CDC ...