What CIC Questions and Answers feature?

The CBIC Certified Infection Control Exam Study Guide (6th edition) emphasizes that a critical initial step in any outbreak investigation is for the infection preventionist to develop a strong understanding of the organism involved, its epidemiology, reservoirs, modes of transmission, and previously reported outbreak sources. Conducting a literature search of similar outbreak investigations provides this foundational knowledge and helps guide a structured, evidence-based investigation.

Pseudomonas aeruginosa is an opportunistic, water-associated pathogen frequently implicated in healthcare-associated outbreaks, particularly in ICUs. Prior outbreak investigations described in the literature commonly identify sources such as sink drains, faucets, respiratory equipment, humidifiers, contaminated medications, and inadequate reprocessing of medical devices. Reviewing published investigations allows the IP to anticipate likely sources, identify high-yield environmental sampling locations, and avoid unnecessary or unfocused interventions.

Options A and D may become appropriate later, depending on outbreak magnitude and reporting requirements, but they are not the initial step. Option B can be helpful but relies on anecdotal experience rather than systematic evidence. The Study Guide stresses that outbreak investigations should begin with background research and hypothesis generation, followed by targeted data collection and analysis.

For the CIC® exam, this question reinforces that effective outbreak management starts with understanding what is already known, making a literature review the most appropriate initial action.

Peripherally inserted central catheter (PICC)-associated bloodstream infections (BSIs) are a significant concern in healthcare settings, and identifying factors contributing to their increase is critical for infection prevention. The Certification Board of Infection Control and Epidemiology (CBIC) emphasizes the "Surveillance and Epidemiologic Investigation" and "Prevention and Control of Infectious Diseases" domains, which align with the Centers for Disease Control and Prevention (CDC) guidelines for preventing intravascular catheter-related infections. The question asks for the intervention most likely to have contributed to the rise in PICC-associated BSIs over four months, requiring an evaluation of each option based on evidence-based practices.

Option C, "Replacement of the intravenous administration sets every 72 hours," is the most likely contributor to the increase. The CDC’s "Guidelines for the Prevention of Intravascular Catheter-Related Infections" (2017) recommend that intravenous administration sets (e.g., tubing for fluids or medications) be replaced no more frequently than every 72-96 hours unless clinically indicated (e.g., contamination or specific therapy requirements). Frequent replacement, such as every 72 hours as a routine practice, can introduce opportunities for contamination during the change process, especially if aseptic technique is not strictly followed. Studies cited in the CDC guidelines, including those by O’Grady et al. (2011), indicate that unnecessary manipulation of catheter systems increases the risk of introducing pathogens, potentially leading to BSIs. A change to a 72-hour replacement schedule, if not previously standard, could explain the observed increase over the past four months.

Option A, "Use of chlorhexidine skin antisepsis during insertion of the PICC," is a recommended practice to reduce BSIs. Chlorhexidine, particularly in a 2% chlorhexidine gluconate with 70% alcohol solution, is the preferred skin antiseptic for catheter insertion due to its broad-spectrum activity and residual effect, as supported by the CDC (2017). This intervention should decrease, not increase, infection rates, making it an unlikely contributor. Option B, "Daily bathing adult intensive care unit patients with chlorhexidine," is another evidence-based strategy to reduce healthcare-associated infections, including BSIs, by decolonizing the skin of pathogens like Staphylococcus aureus. The CDC and SHEA (Society for Healthcare Epidemiology of America) guidelines (2014) endorse chlorhexidine bathing in intensive care units, suggesting it should lower, not raise, BSI rates. Option D, "Use of a positive pressure device on the PICC," aims to prevent catheter occlusion and reduce the need for frequent flushing, which could theoretically decrease infection risk by minimizing manipulation. However, there is no strong evidence linking positive pressure devices to increased BSIs; if improperly used or maintained, they might contribute marginally, but this is less likely than the impact of frequent tubing changes.

The CBIC Practice Analysis (2022) and CDC guidelines highlight that deviations from optimal catheter maintenance practices, such as overly frequent administration set replacements, can increase infection risk. Given the four-month timeframe and the focus on an intervention’s potential negative impact, Option C stands out as the most plausible contributor due to the increased manipulation and contamination risk associated with routine 72-hour replacements.

The Certification Study Guide (6th edition) identifies coagulase-negative staphylococci (CoNS) as among the most common causes of surgical site infections following orthopedic implant procedures, including total hip replacement. These organisms are part of normal human skin flora and are therefore a frequent source of contamination during surgery, even when aseptic technique is followed. Their importance is heightened in procedures involving prosthetic material because CoNS have a strong ability to adhere to foreign bodies and form biofilms, which protect bacteria from host defenses and antimicrobial therapy.

The study guide emphasizes that SSIs following joint replacement procedures often present within 30 to 60 days postoperatively and are typically caused by gram-positive cocci, particularly Staphylococcus aureus and coagulase-negative staphylococci. CoNS are especially associated with indolent or delayed infections involving implanted devices, making them a critical teaching point in joint replacement programs.

The other organisms listed are less likely causes in this setting. Escherichia coli and Pseudomonas aeruginosa are more commonly associated with gastrointestinal, urinary, or moist environmental sources rather than clean orthopedic procedures. Group A streptococci may cause acute SSIs but are far less common in prosthetic joint infections.

Understanding organism-specific risks allows infection preventionists to target prevention strategies, antimicrobial prophylaxis, and surveillance effectively—key competencies tested on the CIC exam.