Minimizing hospital acquired intensive care unit infections: A focus on prevention

Abstract

Hospital-acquired infections (HAIs) are a leading cause of morbidity and mortality in intensive care units (ICUs), largely driven by invasive devices, immunosuppression, and prolonged hospitalization. Despite available guidelines, prevention strategies remain inconsistently applied across settings. This narrative review synthesized evidence from PubMed (2020-2025) and key guideline documents (World Health Organization, Centers for Disease Control and Prevention, Infectious Diseases Society of America, Society for Healthcare Epidemiology of America), focusing on staff-level, patient-level, and systemic interventions for ICU infection prevention. Eligible sources included systematic reviews, clinical trials, consensus statements, and implementation studies. Effective staff-level strategies include strict hand hygiene, correct use of personal protective equipment, vaccination, and decontamination of personal devices, supported by audits and feedback. Patient-level care bundles targeting ventilator-associated pneumonia, central line-associated bloodstream infection, and catheter-associated urinary tract infection reduce device-related complications, though real-world adherence varies. Systemic measures such as closed ICU models, adequate nurse-to-patient ratios, triage protocols, and single-patient rooms, further mitigate infection risks. Implementation barriers include resource limitations, compliance gaps, and ethical considerations regarding futile care. Preventing ICU-acquired infections requires coordinated, multifaceted strategies embedded into daily practice. Sustained progress depends on leadership, continuous education, auditing, and adaptation of international frameworks to local contexts.

Key Words: Hospital-acquired infection; Intensive care units; Infection control; Care bundles; Hand hygiene; Device-associated infection

Core Tip: Hospital-acquired infections remain frequent in intensive care units (ICUs), contributing to excess mortality, prolonged hospitalization, and higher costs. Evidence shows that adherence to hand hygiene, staff vaccination, and device-care bundles can substantially reduce ventilator-associated pneumonia, bloodstream, and urinary tract infections. Systemic measures such as adequate nurse-to-patient ratios, single-patient rooms, and closed ICU models further improve outcomes. This review integrates staff-level, patient-level, and organizational strategies, highlighting that effective prevention requires not only technical measures but consistent implementation, monitoring, and adaptation across different healthcare settings to achieve sustainable reductions in infection rates.

INTRODUCTION

Hospital-acquired infections (HAIs) are a major concern in intensive care units (ICUs), where critically ill patients face a heightened risk due to frequent use of invasive devices, immunosuppression, and prolonged hospitalization[1]. The most common pathogens associated with ICU-acquired infection are gram-negative bacteria, among these, Klebsiella species are frequently identified as the leading pathogen, followed closely by Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter species[2]. The prevalence of ICU-acquired infections is estimated at approximately 22%, with a significant impact on patient outcomes[3]. Compared to community-acquired infections, they are associated with increased mortality, with an odds ratio (OR) of 1.32. These infections also contribute to prolonged ICU and hospital stays: Patients with ICU-onset bloodstream infections have a median ICU stay of 13 days, compared to 5 days for those with infections present on admission[4]. The resulting healthcare burden is substantial, driven by longer hospitalizations, increased antibiotic use, and the need for additional medical interventions[5].

Preventing ICU-acquired infections hinges on a structured approach that integrates clinical protocols, behavioral discipline, and organizational culture[6]. Sustained prevention depends less on isolated measures and more on embedding infection control within everyday clinical routines[7]. This requires not only equipping healthcare professionals with up-to-date knowledge but fostering a collective sense of accountability within the care team[8]. Institutional commitment to continuous education, quality improvement, and monitoring of outcomes is essential to ensure that prevention efforts translate into real-world practice[6,9].

Implementation of evidence-based infection prevention strategies has been shown to significantly decrease the incidence of HAIs and their complications, with the Centers for Disease Control and Prevention (CDC) reporting a 58% reduction in central line associated blood stream infections (CLABSI) rates in ICUs following widespread adoption of prevention protocols[5]. By reducing the incidence of infections, initiatives targeting HAI prevention in ICUs have demonstrated overall healthcare savings of $68.8 million and a return on investment of 765% over three years[10].

The evidence base for ICU infection prevention remains incomplete. Implementation of preventive strategies is inconsistent across institutions, with variable adherence and limited generalizability to different resource settings[11]. Evidence on the long-term sustainability of infection control programs is limited[12], and the lack of high-quality studies from low- and middle-income countries restricts their global applicability[13].

Although several guidelines from different institutions, such as World Health Organization (WHO) and CDC, provide frameworks for infection prevention, there remains a lack of recent reviews synthesizing evidence across staff-level, patient-level, and systemic strategies within a single framework. Previous reports have primarily emphasized single interventions rather than integrated approaches. This narrative review aims to provide a comprehensive report synthesizing practical insights based on available clinical evidence on prevention of HAIs in the ICU.

METHODS

This work was conducted as a narrative review with the objective of synthesizing contemporary evidence on strategies to prevent HAIs in ICUs. A structured search was performed in PubMed, which was considered the most comprehensive biomedical database for the subject. The core search string combined the following key terms: “ICU infection prevention”, “hospital-acquired infection”, “healthcare-associated infection”, “infection control”, and “intensive care unit”. To capture intervention-specific evidence, we employed a broad set of secondary terms, including “hand hygiene”, “personal protective equipment”, “healthcare worker vaccination”, “staff attire”, “device contamination”, “ventilator-associated pneumonia”, “central line-associated bloodstream infection”, “catheter-associated urinary tract infection”, “care bundles”, “audit and feedback”, “closed ICU model”, “nurse-to-patient ratio”, “single-patient rooms”, and “futile care”. Boolean operators (AND, OR) were applied to refine the retrieval strategy. The search focused on publications between January 2020 and August 2025, ensuring inclusion of the most recent clinical guidelines, systematic reviews, and implementation studies. Earlier seminal references were incorporated selectively when necessary to provide historical context (e.g., WHO “5 Moments of Hand Hygiene”). Eligible sources included systematic reviews, meta-analyses, randomized controlled trials, prospective and retrospective cohort studies, consensus statements, and guideline documents. Only peer-reviewed articles published in English were considered.

INFECTION PREVENTION IN ICU

This section discusses preventive measures intended to reduce the incidence of ICU acquired infection. Three major topics related to ICU infection prevention will be addressed: Staff level precautions, patient-focused interventions and systemic institutional measures.

Staff-level precautions

Key measures for ICU infection prevention include hand hygiene, personal protective equipment (PPE), up-to-date immunizations, decontamination of personal devices, and adherence to attire standards (Table 1). These practices, reinforced through structured training, audits, and feedback, can effectively reduce the risk of infection transmission.

Table 1 Staff-level infection prevention strategies and key components.

Strategy	Key components
Hand hygiene	WHO 5 Moments framework, audits, alcohol-based rub availability, behavioral nudges
Personal protective equipment (PPE)	Proper donning and doffing techniques, use during high transmission or aerosol-generating procedures
Immunizations	Ensure all ICU personnel are vaccinated against transmissible diseases (e.g., influenza, hepatitis B)
Device decontamination	Regular cleaning of mobile phones and stethoscopes
Attire standards	Short sleeves, no rings or watches, daily uniform change
Structured protocol	Training, audits, and feedback to improve compliance

WHO: World Health Organization; ICU: Intensive care unit.

Hand hygiene is the single most important measure to prevent HAIs in ICUs, yet adherence remains suboptimal, with a global compliance average of 59.6%, ranging from 64.5% in high-income to 9.1% in low-income countries[14]. Compliance temporarily improved during the coronavirus disease 2019 (COVID-19) pandemic, rising from 54.5% to 70.1%[15], but declined post-pandemic[16]. Lower compliance is particularly observed among consultants and non-ICU staff compared to ICU nurses[17,18]. The WHO’s “5 Moments of Hand Hygiene” remains the cornerstone framework, advising hygiene before touching a patient, before clean/aseptic procedures, after body fluid exposure/risk, after touching a patient, and after touching a patient's surroundings[19]. The Infectious Diseases Society of America (IDSA), together with Society for Healthcare Epidemiology of America (SHEA) and Association for Professionals in Infection Control and Epidemiology (APIC), recommends combining alcohol-based rub at point-of-care, unit-specific education, electronic or direct monitoring with feedback, and leadership engagement[20]. Complementary behavioral interventions, including co-designed visual cues and motivational nudges at key failure points, further improve compliance when staff are actively involved[21].

PPE plays a critical role in minimizing infection transmission in ICU. Its effectiveness is highly dependent on correct donning and doffing, as observational studies show that improper technique frequently causes self-contamination[22]. Following standardized protocols from WHO and CDC substantially reduces these failures[23]. Use of respirators is particularly important when community transmission of respiratory viruses is high, when caring for patients with suspected or confirmed infection, or during aerosol-generating procedures[24,25].

Personal immunization of ICU personnel is essential to prevent nosocomial transmission of infectious diseases. Healthcare workers are at risk of both acquiring and transmitting influenza, measles, mumps, rubella, varicella, pertussis, and hepatitis B[26]. Vaccination not only protects healthcare workers themselves but also reduces spread to patients and colleagues[27,28]. In Italian hospitals, the incidence of COVID-19 infection was 4.88 cases per 100000 person-days among vaccinated staff compared to 103.55 among non-vaccinated, corresponding to a 95% reduction in risk[29]. Whether healthcare facilities should recruit only vaccinated staff or provide vaccination after hiring remains debated[28]. Recruitment policies vary globally, but on-site vaccination programs at employment entry are essential to ensure full coverage of ICU personnel[30,31].

Additional strategies target contamination of personal equipment. Nearly all healthcare workers’ mobile phones harbor potentially pathogenic and antibiotic-resistant bacteria, as well as fungi and viruses[32-34]. Stethoscopes show contamination rates exceeding 80%, often with S. aureus, Pseudomonas, and Klebsiella[35,36]. Best attire practices include wearing short-sleeved scrubs, avoiding wristwatches and rings, and changing uniforms daily These measures reduce microbial load and limit the transfer of multidrug-resistant organisms between patients and the ICU environment[37-39].

A structured protocol based on staff training, auditing, and feedback is necessary to implement these precautions. Standardized training for ICU staff on infection prevention improves adherence to best practices and improves infection control behaviors and patient safety[40]. Providing structured feedback to staff based on audit results is another critical component. Feedback should be specific, actionable, and delivered in a supportive manner to reinforce correct behaviors and address deficiencies. Studies show that combining education, audit, and feedback leads to significant reductions in ICU-acquired infections[41,42]. In a prospective study in COVID ICUs, implementation of structured hand hygiene auditing with timely feedback increased total adherence from 26.7% to 68.4% over six months, with an overall compliance rate of 65.3%. Improved adherence correlated with a reduction in device-associated infection rates from 24.7 to 11.5 per 1000 device days[43].

Patient-level precautions

This section will summarize the three main care bundles used in the ICU to reduce risk of infection in patients (Table 2): Ventilator care bundle, central line care bundle and urinary catheter care bundle.

Table 2 Patient-level infection prevention strategies and key components.

Strategy	Key components
VAP bundle	Minimized sedation, daily sedation interruption, oral care without chlorhexidine, early mobilization, head-of-bed elevation
CLABSI bundle	Sterile PPE, chlorhexidine skin prep, subclavian access, chlorhexidine dressings, insertion and maintenance auditing
CAUTI bundle	Use catheter only when necessary, aseptic insertion by trained staff, smallest catheter size, daily reassessment and prompt removal

VAP: Ventilator associated pneumonia; PPE: Personal protective equipment; CAUTI: Catheter-associated urinary tract infections; CLABSI: Central line associated blood stream infections.

Patients in the ICU frequently undergo invasive procedures such as mechanical ventilation (MV) and placement of central venous lines, to reduce the complications associated with these techniques care bundles were implemented[44]. A care bundle is defined as a set of evidence-based practices or interventions that, when performed collectively and reliably, are intended to improve patient outcomes and the quality of care for a specific clinical condition or procedure[45]. Before their implementation, the standard practice to prevent infection spread in healthcare settings relied on individual, often isolated, evidence-based interventions rather than a coordinated, systematic approach[46].

Ventilator associated pneumonia (VAP) is a serious complication during MV, with an incidence up to 30% in ICU patients undergoing MV[47]. To reduce this risk, VAP care bundles were put into place in different institutions. The IDSA, in its 2022 guideline, highlights the most consistently supported elements for VAP prevention[48]. Minimizing sedation whenever possible is advised, with a strong preference for non-benzodiazepine agents, such as dexmedetomidine or propofol, as these are associated with shorter durations of MV and ICU stay[49]. Daily sedation interruption and assessment of readiness to extubate are other key elements, as these interventions are independently associated with less time to extubation and lower ventilator mortality[48]. Oral care with toothbrushing, but without the use of chlorhexidine has also been associated with lower rates of hospital-acquired pneumonia, including VAP, as well as reductions in ICU mortality, ICU length of stay, and days of MV[50]. Early exercise and mobilization have been shown to shorten the duration of MV, reduce ICU length of stay and lower VAP rates[51]. At least one physical therapy session per day, three days per week, is recommended[52]. Another component of the VAP bundle is a head of bed elevation between 30-45 degrees. A 2024 systematic review and meta-analysis of six randomized trials demonstrated that head-of-bed elevation at 45° significantly decreased the incidence of ventilator-associated pneumonia compared with 30° (OR = 0.51, 95%CI: 0.31-0.84; P < 0.05)[53]. However, minimizing sedation and reducing prolonged intubation are not without risks. Reported complications include an increased incidence of unplanned extubations and potential subglottic stenosis[54,55]. Similarly, positioning strategies such as elevating the head of the bed to 45°, although effective in reducing ventilator-associated pneumonia, have been associated with nearly double the risk of pressure ulcer development (OR = 1.95, 95%CI: 1.12-3.37; P < 0.05)[53]. These examples underscore the need to balance infection prevention with patient safety and individualized care.

CLABSI are another serious complication in the ICU setting, with an estimated incidence of 1-6 per 1000 catheter-days[56]. In their 2022 practice recommendations SHEA/IDSA/APIC described the optimal interventions to reduce this risk[57]. This bundle approach focuses on both catheter insertion and maintenance components. Provider hygiene and the use of sterile PPE, as outlined in its dedicated section, is of paramount importance during catheter insertion, as well as patients skin preparation with an alcoholic chlorhexidine solution[5]. The subclavian site is preferred over other central venous access sites in the ICU setting to reduce infectious complications. Compared to the femoral and internal jugular sites, the subclavian site includes a lower density of skin flora and a longer subcutaneous tract, both of which decrease the likelihood of microbial entry and catheter colonization[58]. After insertion, the use of chlorhexidine-containing dressings has been associated with a sustained and significant reduction in catheter-associated bloodstream infection rates[59]. Surveillance and auditing of CLABSI rates are another essential part to reduce the incidence of infections[60].

Catheter-associated urinary tract infections (CAUTI) have an estimated incidence of 1.2-7.8 per 1000 catheter days in adult ICUs[61]. The absolute mortality difference for CAUTI in ICU patients is approximately 9.9%, compared to 29.0% for VAP and 31.6% for CLABSI[62], but it is regardless independently associated with increased mortality[63]. This subject was addressed in the 2022 practice recommendations by SHEA/IDSA/APIC, highlighting different essential practices that should be put into place[64]. Urinary catheters should be inserted only when necessary for patient care in ICU patients, removed as soon as indications no longer exist, and assessed daily for ongoing necessity to minimize the risk of CAUTI[65]. It must be ensured that only trained providers proceed with catheter insertion[66] and the use of aseptic technique and sterile equipment for catheter insertion is advised[67]. The smallest feasible urinary catheter size should be used to minimize trauma, this should be done to avoid mucosal injury from larger catheters or repeated attempts, which facilitates bacterial entry and colonization[68].

Despite their proven efficacy, implementation of care bundles in real-world ICU practice is often constrained by contextual challenges. In high-income settings, adherence is threatened by staff workload, burnout, and variable compliance with daily protocols[69], while in low- and middle-income countries resource limitations such as shortages of sterile equipment, limited access to trained personnel, and overcrowding reduce feasibility and sustainability[70]. Even when bundles are applied, balancing infection prevention with patient safety requires constant vigilance, as illustrated by complications like unplanned extubations or pressure ulcers associated with sedation minimization and head-of-bed elevation[71]. These examples highlight that the success of patient-level bundles depends not only on technical design but also on organizational culture, staff engagement, and continuous auditing to ensure translation into consistent clinical practice[72,73].

To summarize, prevention of VAP, CLABSI, and CAUTI begins with ensuring that invasive devices are used only when clinically indicated. Daily reassessment of their necessity is essential, with prompt removal as soon as the patient is ready, to reduce the duration of exposure and the associated infection risk[48,57,64]. However, their real-world effectiveness is often constrained by barriers such as resource limitations, variability in staff compliance, and the need for sustained auditing and feedback to ensure consistent application.

Systemic precautions

This section will summarize different precautions that can be implemented on a systemic level (Table 3): Futile care, ICU models, single patient rooms, nurse-to-patient ratios, palliative care, early goal discussions and nursing staff roles.

Table 3 Systemic infection prevention strategies and details.

Strategy	Details
ICU triage and admission protocols	Avoid futile care and reduce overcrowding
Closed ICU model	24/7 oversight by intensivist-led team
Single patient rooms	Reduce MDRO transmission
Nurse-to-patient ratios	Improve care quality and reduce infection risk
Palliative care and early goal discussions	Limit non-beneficial interventions and exposure to infection

ICU: Intensive care unit; MDRO: Multidrug-resistant organisms.

Beyond already discussed personal precautions by healthcare staff and bedside protocols, systemic infection prevention measures must be taken to reduce infection spread. A study by Vincent et al[74] presents strong evidence that the risk of infection increases with ICU admission and especially with longer ICU stays. Additionally, according to a study by Huynh et al[75], 11% of ICU patients receive futile care, defined as medical interventions unlikely to provide meaningful benefit for critically ill patients. These patients often had prolonged stays (up to 58 days), causing overcrowding in the ICU, and 85% died within 6 months. Overcrowded ICUs are associated with higher rates of cross-contamination, lower staff-to-patient ratios, and reduced adherence to infection control practices, all of which increase infection risks for everyone in the unit[76]. When patients receive prolonged, non-beneficial care such as MV, central line infusions, or dialysis with no expectation of recovery, they are exposed longer to invasive devices and hospital-acquired pathogens[77]. This extended exposure significantly raises their risk of infections such as VAP, CLABSI and CAUTI[75]. This is not merely a burden on individual patients; intensivists have warned that such practices promote antimicrobial resistance, which impedes infection control across the ICU and harms other patients[76]. These findings highlight the need for institutional-level interventions that go beyond bedside protocols. These patients also occupy ICU beds for long periods and overcrowd ICUs. One of the solutions would be to implement ICU triage protocols, admission criteria and decision-aid tools to reduce inappropriate ICU admissions[78]. A study conducted at Wroclaw University Hospital in Poland analyzed ICU protocols aimed at identifying and withholding or withdrawing such futile therapies[79]. In 9% of patients, treatments like cardiopulmonary resuscitation, MV, or renal replacement therapy were deemed medically inappropriate and were either withheld or withdrawn. Importantly, all these patients died during hospitalization, underlining the clinical accuracy of the futility assessments and the ethical shift toward palliative care. It must be noted that effective communication with patient families plays a very important role in implementing these protocols. Systemic measures that support early goals-of-care discussions, palliative care referrals, and appropriate ICU triage can reduce these non-beneficial admissions. Such systemic approaches improve the efficiency and safety of critical care, allowing ICUs to focus resources on patients who are most likely to benefit, while simultaneously reducing infection risks for all[80]. It should be noted that withdrawal of life-sustaining therapies varies significantly across countries depending on legal and cultural frameworks. While withdrawal is universally accepted in brain death, decisions in other scenarios must comply with medicolegal standards, which directly influence ICU length of stay and, consequently, infection risk[81,82]. By reducing prolonged, non-beneficial interventions, systemic strategies such as triage protocols and early palliative care not only optimize ICU resource use but also directly limit infection risk by shortening unnecessary exposure to invasive devices and mitigating cross-contamination associated with overcrowding[83-85].

ICUs can be managed in two ways: In open ICUs, care is provided by the admitting physician from any specialty, who may not always be present; in closed ICUs, a dedicated team led by intensivists oversees patient care around the clock[86]. Recent systematic review and meta-analysis show a clear benefit in many aspects of having a closed type ICU[87]. In addition to organizational structure, the physical design of the ICU environment also plays a critical role in infection prevention and patient outcomes. Single room ICU design contributes significantly to the reduction of cross transmission of MRD-bacteria. A 2024 systematic review and meta-analysis found that single-patient ICU rooms significantly reduced the acquisition rate of multidrug-resistant organisms (OR = 0.41, 95%CI: 0.23-0.73), as well as overall nosocomial infection and colonization rates, compared to multi-patient rooms[88]. Adequate nurse-to-patient ratios are associated with reduced risk of VAP, CLABSI, and other HAIs[89]. Having a lower nurse-to-patient ratio reduces compliance to patient care infection prevention bundles and reduces quality of care.

Ethical considerations are integral to ICU infection prevention strategies[90]. Prolonged use of invasive interventions should be carefully evaluated to avoid unnecessary exposure to infection risks and align with patient-centered values of beneficence and non-maleficence[91]. In this context, early integration of palliative care and transparent communication with families are essential[92]. Nursing leadership has a pivotal role in embedding infection prevention into everyday practice, advocating for adequate staffing ratios, ensuring protocol adherence, and fostering a culture of safety that balances patient autonomy, family involvement, and infection control priorities[9].

While the preceding sections outline evidence-based staff-level, patient-level, and systemic interventions, translating these strategies into routine nursing practice requires concise and actionable guidance. To this end, a quick-start checklist of practical nursing actions is provided (Table 4), synthesizing the most relevant measures into a tool designed to support consistent implementation at the bedside.

Table 4 Nursing quick-start checklist for intensive care unit infection prevention.

Domain	Practical nursing actions
Hand hygiene	Perform hand hygiene at all WHO 5 Moments; ensure alcohol-based rub available at bedside
Personal protective equipment	Correct donning/doffing; use mask/respirator for aerosol-generating procedures
Invasive devices	Verify daily necessity of central lines, urinary catheters, and ventilators; request removal when no longer indicated
Ventilator care	Elevate head of bed 30°-45°; provide daily sedation interruption and readiness-to-wean assessment
Oral care and mobilization	Perform oral care with toothbrushing (no chlorhexidine); assist early mobilization/exercise at least once daily
Catheter care	Use aseptic technique during insertion; reassess and document catheter necessity daily
Environmental hygiene	Disinfect stethoscopes and mobile devices once per shift; ensure clean uniforms and bare forearms
Audit and feedback	Participate in hand hygiene/device audits; provide and accept immediate feedback
Family/patient engagement	Educate families on hand hygiene before and after patient contact; encourage participation in infection-prevention routines

WHO: World Health Organization.

DISCUSSION

This narrative review summarizes the most recent evidence on prevention of hospital acquired ICU infections. These infections are effectively driven by prolonged exposure to invasive devices and the immunocompromised state of critically ill patients. Prevention efforts rely on a multifaceted strategy combining healthcare staff precautions, patient-focused practices, and institutional protocols. Key elements include rigorous hand hygiene, proper use of PPE, and immunization of ICU personnel, all reinforced through structured training, audits, and feedback. These interventions aim to minimize infection transmission risks by targeting both behavioral and organizational factors.

Two recent studies support the prevention strategies outlined in this review. In a recent systematic review Hajiyeva et al[93] examined different studies on quality management interventions for reducing HAI. They found that structured, multifaceted approaches, especially those combining education, protocol standardization, audit-feedback cycles, and leadership involvement, were most effective when embedded into hospital-wide quality systems. Similarly, Schinas et al[94] proposed a five-pillar strategy for reducing multidrug-resistant bacterial transmission in ICUs. These pillars include hygiene promotion, patient management, surveillance, antimicrobial stewardship, and institutional leadership. The authors emphasized that technical solutions alone are insufficient without behavioral change, multidisciplinary collaboration, and organizational support. Together, these studies confirm the core thesis of this review: ICU infection prevention requires coordinated, sustained, and system-level interventions to achieve measurable and lasting impact.

Global experience demonstrates that preventing ICU-acquired infections is not primarily limited by knowledge of effective measures, but by the challenges of translating evidence into sustainable practice. Hand hygiene, PPE use, and care bundles are universally recommended, yet compliance remains inconsistent: In some low- and middle-income countries, adherence falls below 10%, reflecting supply chain instability and infrastructural deficits[95,96], while in high-income countries, audit-driven improvements are often undermined by staff turnover, workload, and “audit fatigue” once monitoring is relaxed[7,97]. Systemic solutions such as closed ICUs or single-patient rooms are effective but often limited by cost and staffing, while real progress can still be made through strong organizational culture and leadership. Importantly, interventions carry trade-offs that complicate implementation: Minimizing sedation reduces ventilator-associated pneumonia but increases unplanned extubations; head-of-bed elevation lowers pneumonia rates but heightens pressure-ulcer risk. These examples underscore that infection prevention is not a checklist of technical tasks but an adaptive process requiring alignment of protocols with local epidemiology, workforce capacity, and organizational culture. Sustainable solutions therefore depend on leadership engagement, multidisciplinary collaboration, and tailoring strategies to context, whether by introducing low-cost checklists and locally produced alcohol rub in resource-limited settings, or by embedding real-time electronic monitoring and structured palliative care pathways in high-resource ICUs. Only by integrating behavioral, ethical, and systemic dimensions can infection prevention programs achieve durable global impact.

A key finding of this review is that successful infection prevention depends on aligning evidence-based protocols with day-to-day ICU practice. This includes staff-level behaviors (e.g., hand hygiene, PPE use), technical interventions (e.g., catheter care), and systemic policies (e.g., triage criteria, closed ICU models). Interventions such as staff immunization and personal device decontamination, though less emphasized in older literature, are emerging as relevant and practical additions.

The unique contribution of this narrative review is its structured synthesis that integrates staff-level, patient-level, and systemic interventions. While previous reports often addressed these domains separately, this review underscores their interdependence and emphasizes that sustainable infection prevention requires their coordinated implementation.

There are several limitations to this manuscript. As a narrative review, it lacks the methodological rigor of a systematic review and may be subject to selection bias. Heterogeneity in implementation settings limits generalizability. However, its strengths include integration of high-quality recent evidence and its structured focus on distinct domains of infection prevention, offering actionable insights for ICU teams.

CONCLUSION

HAI in the ICU are best prevented through a coordinated approach that integrates staff-level precautions, patient-focused bundles, and systemic institutional measures. Sustained progress depends on embedding these strategies into routine workflows, reinforced by auditing, feedback, and leadership support. Core practices include strict hand hygiene, correct PPE use, vaccination of healthcare personnel, and daily reassessment of invasive devices, complemented by care bundles for ventilator-associated pneumonia, CLABSI, and CAUTI. At the systemic level, closed ICU models, single-patient rooms, adequate nurse-to-patient ratios, and triage protocols that avoid futile care reduce overcrowding and unnecessary pathogen exposure. Nursing teams are essential partners in operationalizing checklists, monitoring adherence, and fostering a culture of safety that extends to patient and family engagement. Ethical considerations, such as early goals-of-care discussions and integration of palliative care, further align infection prevention with patient-centered values. Future work should focus on multicenter quality improvement initiatives and local adaptation of existing frameworks, including those from the WHO, CDC, IDSA, SHEA, and other professional societies, to ensure sustainable and globally applicable strategies.