Overview
Definition:
Catheter-associated infections (CAIs) in the Pediatric Intensive Care Unit (PICU) are nosocomial infections related to the use of indwelling urinary catheters (CAUTI) or central venous catheters (CLABSI)
These infections are a significant cause of morbidity and mortality in critically ill children and represent a major healthcare-associated burden.
Epidemiology:
The incidence of CAUTI and CLABSI varies widely depending on patient population, catheter type, duration of use, and adherence to infection control practices
In PICUs, CLABSIs are a major concern, with reported rates ranging from 2 to 15 per 1000 central line days
CAUTIs are also common, particularly in children requiring prolonged bladder drainage, with rates of 5-25 per 1000 urinary catheter days
Risk factors include prolonged catheterization, immunocompromise, severity of illness, and breaches in aseptic technique.
Clinical Significance:
CAIs in PICU patients can lead to severe complications such as sepsis, organ dysfunction, prolonged hospital stays, increased healthcare costs, and increased mortality
Early recognition and aggressive prevention strategies are crucial for improving patient outcomes and reducing the burden of these preventable infections
Understanding and implementing evidence-based prevention bundles is paramount for all pediatric residents and fellows preparing for their DNB and NEET SS examinations.
Prevention Bundles
Central Line Bundle:
The central line bundle (CLB) is a multipronged approach to prevent CLABSIs
It includes: Hand hygiene before and after patient contact, maximal sterile barrier precautions during central venous catheter insertion, chlorhexidine skin antisepsis, optimal catheter site selection, and daily review of catheter necessity with prompt removal when no longer indicated.
Urinary Catheter Bundle:
The urinary catheter bundle (UCB) aims to prevent CAUTIs
Key components include: strict adherence to aseptic technique during insertion, maintenance of a closed drainage system, regular emptying of the collection bag, daily review of catheter necessity and timely removal, and ensuring unobstructed urine flow
Catheter securement is also vital to prevent urethral trauma.
Implementation Strategies:
Effective implementation requires multidisciplinary team involvement, including physicians, nurses, and infection control specialists
Regular education, performance monitoring, feedback, and addressing barriers to compliance are essential
Utilizing checklists and standardized protocols can enhance adherence
Continuous quality improvement initiatives are key to sustaining low CAI rates.
Evidence Base:
Numerous studies and national initiatives have demonstrated that implementing these bundles significantly reduces the incidence of CLABSIs and CAUTIs
The Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) endorse these bundles as standard of care in critically ill populations.
Risk Factors And Pathogenesis
Microbial Colonization:
Microorganisms, typically skin flora (e.g., Staphylococcus epidermidis, Staphylococcus aureus) or Gram-negative bacilli, can colonize the catheter surface
This colonization can occur via direct inoculation at insertion, migration along the external surface of the catheter, or retrograde migration through the lumen after contamination of the catheter hub.
Catheter Material And Design:
The material of the catheter can influence biofilm formation
Some coatings (e.g., antimicrobial impregnated catheters) may reduce the risk of colonization and infection
Catheter design, including the number of lumens and hub complexity, can also play a role.
Patient Specific Factors:
Critical illness, underlying conditions (e.g., immunocompromise, hematologic malignancies), malnutrition, prolonged antibiotic use, and colonization with multidrug-resistant organisms increase the susceptibility to CAIs
The pediatric population itself has unique anatomical and physiological considerations.
Healthcare Provider Factors:
Breaches in hand hygiene, improper aseptic technique during insertion and maintenance, and failure to promptly remove unnecessary catheters are significant contributing factors to CAIs.
Clinical Presentation And Diagnosis
Signs Of Clabsi:
Fever or hypothermia, new-onset leukocytosis or leukopenia, hemodynamic instability (hypotension, vasopressor requirement), and signs of end-organ dysfunction (e.g., altered mental status, decreased urine output)
Local signs at the insertion site (erythema, purulence) may or may not be present.
Signs Of Cauti:
Fever, new-onset flank pain, suprapubic tenderness, pelvic pain, dysuria, urgency, frequency, or new-onset incontinence in a child with a urinary catheter
Cloudy or malodorous urine, elevated white blood cell count, or unexplained deterioration in clinical status can also be indicative.
Diagnostic Criteria:
For CLABSI: Positive blood cultures (peripheral and from catheter tip if removed) with a characteristic differential time to positivity, or a clinical diagnosis of bloodstream infection in conjunction with signs of systemic inflammation and a positive catheter tip culture (>15 colony-forming units/mm)
For CAUTI: Signs and symptoms of UTI with at least one of the following: positive urine culture (≥10^5 CFU/mL in uncomplicated cases, or ≥10^2-10^3 CFU/mL in symptomatic patients with specific organisms), positive urine dipstick (leukocyte esterase, nitrites), or pyuria.
Investigations:
Blood cultures (from peripheral vein and/or catheter lumens), urine culture and sensitivity, complete blood count with differential, C-reactive protein (CRP), procalcitonin, and imaging (e.g., chest X-ray, ultrasound of abdomen/pelvis, echocardiogram to rule out endocarditis in suspected CLABSI).
Management Of Catheter Associated Infections
Initial Management:
Prompt recognition of signs and symptoms is critical
Empiric broad-spectrum antibiotic therapy should be initiated immediately after obtaining appropriate cultures
Fluid resuscitation and hemodynamic support are essential for patients with sepsis.
Catheter Management:
For suspected CLABSI, removal of the infected catheter is usually recommended, especially in severe cases or if treatment is delayed
If the catheter is removed, peripheral blood cultures should be obtained from a new insertion site
For CAUTI, removal of the urinary catheter if no longer indicated, or if severe infection is present, is advisable
Maintaining a closed drainage system and ensuring adequate hydration are important.
Antimicrobial Therapy:
Antibiotic selection should be guided by local antibiograms, patient factors, and culture results
Common empiric choices for CLABSI include vancomycin (for Gram-positive coverage, especially MRSA) and a third-generation cephalosporin or antipseudomonal penicillin/cephalosporin (for Gram-negative coverage)
For CAUTI, trimethoprim-sulfamethoxazole, nitrofurantoin, or cephalosporins are often used
Duration of therapy typically ranges from 7 to 14 days, depending on the severity and organism.
Supportive Care:
Aggressive supportive care, including mechanical ventilation, vasopressor support, and management of organ dysfunction, is crucial
Nutritional support and pain management are also integral components of care.
Key Points
Exam Focus:
Prevention bundles are HIGH-YIELD for DNB/NEET SS
Know the components of central line and urinary catheter bundles intimately
Understand the rationale behind each component
Be familiar with diagnostic criteria and empiric management of CLABSI and CAUTI in PICU.
Clinical Pearls:
Never underestimate the importance of hand hygiene and maximal sterile barrier precautions during insertion
Daily review of catheter necessity is a non-negotiable step
Prompt removal of catheters when no longer indicated is the single most effective strategy
Consider fungal infections in prolonged antibiotic use or immunocompromised hosts.
Common Mistakes:
Failure to adhere to all components of the bundle
Delay in catheter removal
Inadequate culturing before antibiotic initiation
Inappropriate choice of empiric antibiotics
Lack of multidisciplinary team engagement in infection prevention initiatives
Not considering non-infectious causes of fever in critically ill children.