Epidemiology, risk factors, and antimicrobial resistance of nosocomial infections in the intensive care unit trauma patients: A cross-sectional study

Abstract

Background:

Healthcare-associated infections (HAIs) remain a critical challenge, particularly in trauma patients admitted to intensive care units (ICUs), who are at increased risk due to invasive procedures and prolonged hospitalization. This study aimed to investigate the prevalence, types, causative pathogens, and antibiotic resistance patterns of nosocomial infections in trauma patients.

Materials and Methods:

In this retrospective cross-sectional study conducted from March 2019 to March 2020, 45 trauma patients who developed nosocomial infections 48 h after ICU admission were analyzed. Data were collected from the hospital records and the Iranian Nosocomial Infection Surveillance System.

Results:

Of 557 trauma patients admitted to the ICU, 45 (7.9%) developed 65 episodes of HAIs during the study, of which 12.3% (8/65) were polymicrobial. Ventilator-associated events (VAE) were the most common infection type (58.2%), followed by bloodstream (20.9%), surgical site (14.9%), and urinary tract infections (6%). Acinetobacter spp. was the most frequently isolated pathogen (49.4%), followed by Klebsiella spp. (27.7%). High levels of antibiotic resistance have been observed, particularly in Gram-negative bacteria. No statistically significant associations were found between infection type, trauma severity, or underlying comorbidities.

Conclusion:

VAE and multidrug-resistant Acinetobacter species are major concerns in trauma patients in the ICU. Strengthening infection prevention protocols, especially ventilator care practices, and implementing antimicrobial stewardship programs are essential for mitigating infection risk. Furthermore, enhanced surveillance systems, targeted antibiotic therapy guided by local antibiograms, and multicenter research collaborations are strongly recommended for addressing the emerging threat of antibiotic-resistant nosocomial infections.

INTRODUCTION

Healthcare-associated infections (HAIs) are a significant cause of morbidity, mortality, and healthcare costs worldwide, particularly in critically ill patients.[1] Defined as infections that occur 48 h or more after hospital admission without prior evidence of infection, HAIs remain a persistent challenge despite advancements in medical technologies and infection control practices.[2] The occurrence of HAIs is influenced by several risk factors, including age (particularly infancy and old age), underlying health conditions, prolonged hospital stays, immunosuppression, and intensive care unit (ICU) admission.[3,4,5] According to a systematic review conducted by the World Health Organization (WHO), the prevalence of HAIs is approximately 6.7% in developed countries, whereas it ranges from 5.7% to 19.1% in developing countries, with a general consensus of approximately 10.1% in higher quality studies.[6] In Iran, the reported prevalence rates of HAIs vary between 2.4% and 9.4%.[7]

Patients admitted to ICUs are particularly vulnerable to HAIs because of the frequent use of invasive procedures and devices, immunosuppression, multiple comorbidities, frailty, and advanced age.[8] In trauma patients, this risk is further amplified by the severity of injuries, the need for emergent surgical interventions, mechanical ventilation, central venous access, and extended ICU stay.[9,10] These factors not only compromise host defenses but also increase the likelihood of microbial colonization and infection.[9,10] Although ICUs account for less than 10% of hospital beds, >20% of HAIs occur in these units.[11,12] Common pathogens responsible for HAIs include Staphylococcus aureus, Clostridium difficile, and various Enterococcus species.[13] The widespread use of broad-spectrum antibiotics has led to the emergence of resistant bacterial strains, making infections increasingly difficult to treat.[14] Environmental exposure, such as contact with soil, has also been implicated in infections caused by organisms such as Clostridium spp.[15] The incidence of multidrug-resistant pathogens isolated from ICU patients has been increasing, including methicillin-resistant S. aureus, vancomycin-resistant Enterococcus (VRE), Acinetobacter baumannii, and carbapenem-resistant Enterobacteriaceae.[16,17,18] Infections caused by resistant organisms are associated with higher morbidity, mortality, and healthcare costs.[16,17,18]

Given the importance of the timely identification of emerging pathogens and new patterns of antibiotic resistance, regular epidemiological surveillance is critical. Thus, the present study was conducted to evaluate the distribution of hospital-acquired infections, causative pathogens, and antibiotic resistance patterns among trauma patients admitted to the ICUs of the Al-Zahra Hospital in Isfahan in 2019.

MATERIALS AND METHODS

Study design

This retrospective cross-sectional study was conducted over a 1-year period using a census of eligible infected cases from March 21, 2019, to March 19, 2020, in the ICUs of Al-Zahra Educational and Medical Center, affiliated with Isfahan University of Medical Sciences, Isfahan, Iran. The study protocol was approved by the Ethics Committee of Isfahan University of Medical Sciences (Ethics Code: IR.MUI.MED.REC.1399.786). Owing to the retrospective nature of the study, informed consent was not obtained from the patients. Access to patient data was granted by the Ethics Committee of Isfahan University of Medical Sciences as part of the approved study protocol. As this was a retrospective study, no formal sample size calculation was performed before data collection. However, all available cases of HAIs in ICU trauma patients during the 1-year study were included, representing a complete census of eligible patients. This sample size was deemed feasible and sufficient to provide exploratory insights into the infection patterns and resistance profiles in this high-risk population. However, we acknowledge that retrospective designs may introduce limitations, such as incomplete or missing data, potential misclassification, and selection bias. We aimed to minimize these risks by applying standardized data extraction methods and predefined inclusion criteria.

Inclusion and exclusion criteria

Patients aged 18 years and older who were admitted to the ICU with an initial diagnosis of trauma and who developed an HAI after at least 48 h of ICU admission were included. All trauma patients who developed hospital-acquired infection during the study and met the inclusion criteria were included in the census sampling. No additional selection or sampling strategies were used. Patients with trauma were identified based on physician-documented clinical assessments and trauma-related diagnoses recorded in the hospital’s admission system. Although there was no formal trauma registry, eligible cases were screened using relevant diagnostic terms indicating blunt, penetrating, or multiple injuries. The exclusion criteria were length of ICU stay of <48 h, evidence of infection present at or before ICU admission, or incomplete documentation regarding infection type, causative microorganism, or antibiotic susceptibility profile.

Definitions

HAI was defined based on the Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN) criteria as an infection occurring more than 48 h after hospitalization or within 72 h after discharge in the absence of clinical signs of infection at admission.[19] Diagnoses were verified by infectious disease specialists using a combination of clinical, laboratory, and imaging data. The clinical signs included fever, leukocytosis, or purulent secretions. Laboratory confirmation was based on positive cultures from relevant clinical specimens: blood cultures for bloodstream infections (BSI), endotracheal aspirate or bronchoalveolar lavage for ventilator-associated events (VAE), urine cultures for urinary tract infections (UTI), and wound swabs or tissue cultures for surgical site infections (SSI). Radiological findings, such as new infiltrates on chest radiography for VAE or imaging-confirmed abscess for SSI, were also used as supportive evidence. In cases of diagnostic uncertainty, the final classification was determined by consensus during a multidisciplinary review by infectious disease consultants. The diagnosed infection types included BSI, VAE, UTI, and SSI.

Clinical specimens were collected under sterile conditions from suspected infection sites, including blood, urine, respiratory secretions (e.g., endotracheal aspirates), and wound swabs. All samples were transported to the hospital’s microbiology laboratory and processed within 2 h of collection. Pathogen identification and antimicrobial susceptibility testing were performed according to the Clinical and Laboratory Standards Institute (CLSI) guidelines.[20] Susceptibility was assessed by the disc diffusion method (Kirby–Bauer). The results were interpreted in accordance with CLSI breakpoints.

Data collection

The collected data included demographic characteristics (age and sex), comorbidities, trauma site, trauma severity, time of infection onset, and isolated microorganisms. Trauma severity was assessed using the Revised Trauma Score (RTS), which was recorded at the time of ICU admission to reflect the initial physiologic status. The RTS evaluates respiratory rate, systolic blood pressure, and Glasgow Coma Scale scores, ranging from 0 to 12, with lower scores indicating more severe trauma. In this scoring system, an RTS of 12 corresponds to delayed triage, 11 to urgent triage, and 3–10 to emergency triage, and RTS of <3 indicates death.

Study variables

The primary outcomes were the occurrence and type of HAI, including VAE, BSI, UTI, and SSI. Exposure and predictor variables included age, sex, comorbidities (e.g., diabetes and hypertension), ICU unit of admission, trauma site, and trauma severity. Comorbidities were identified using electronic medical records. Pathogen identification and antibiotic resistance patterns were determined through laboratory analysis of culture specimens obtained from the infection sites. Susceptibility testing was performed in accordance with hospital laboratory protocols using standard antimicrobial panels.

Statistical analysis

The data were analyzed using IBM SPSS Statistics for Windows, version 23.0 (IBM Corp., Armonk, NY, USA). Descriptive statistics, including the mean and frequency distributions, were calculated. The analytical methods used included Pearson’s correlation test for normally distributed data and Spearman’s correlation for nonnormally distributed data. The normality of continuous variables was assessed using the Shapiro–Wilk test. Based on these results, appropriate parametric and nonparametric tests were conducted. Comparisons between groups for continuous variables were conducted using independent t-tests or the Mann–Whitney U-test, where appropriate, and categorical variables were compared using the Chi-square test. Statistical significance was set at P < 0.05.

RESULTS

Patient characteristics

During the study, 557 trauma patients aged >18 years were admitted to the ICUs, of whom 45 (7.9%) developed hospital-acquired infections. Figure 1 illustrates the flow of participants, including the total number of trauma ICU admissions, exclusions, and final cases of HAIs included in the study. The mean age of these patients was 44.07 ± 19.7 years, with males comprising 92.8% (41 patients). The average duration of total hospitalization was 53.37 ± 30.23 days, and the mean ICU stay was 17.78 ± 17.01 days. Diabetes was present in 27.7% of the patients, followed by hypertension (19.3%), and pulmonary disease (19.3%). Most patients (38.6%) were admitted to ICU 3. Head-and-neck trauma was predominant (81.9%), and 60.2% of patients had a RTS of 4–6 [Table 1].

Figure 1.

Participant flow diagram. ICU = Intensive care unit; HAI = Healthcare-associated infection

Table 1.

Demographic information and risk factors in trauma patients admitted to intensive care units with hospital-acquired Infections (n=45 patients)

Variable	Frequency, n (%)†
Underlying disease
None	47 (56.6)
Diabetes	23 (27.7)
Renal	0
Pulmonary	16 (19.3)
Thyroid	2 (2.4)
Hypertension	16 (19.3)
Neurological	2 (2.4)
Cardiac	8 (9.6)
Unspecified	6 (7.2)
ICU admission
ICU 1	12 (14.5)
ICU 2	38 (45.8)
ICU 3	32 (38.6)
ICU neurosurgery	1 (1.2)
Trauma site
Head and neck	68 (81.9)
Chest	19 (22.9)
Abdomen and pelvis	7 (8.4)
Limbs	22 (26.5)
Multiple	4 (4.8)
Trauma severity (RTS)
1–3	0
4–6	50 (60.2)
7–9	33 (39.8)
10–12	0
>12	0

^†Patients may be represented in more than one category within each variable; thus, percentages may exceed 100%. Data are presented as n (%). ICU=Intensive care unit; RTS=Revised trauma score

Infection types and frequency

A total of 65 nosocomial infections were documented in 45 patients. VAE accounted for 58.2% (39/65) of cases, followed by BSI at 20.9% (13/65), SSI at 14.9% (9/65), and UTI at 6% (4/65) [Figure 2]. Notably, 16 patients had polymicrobial infection. Thirty patients experienced a single infection episode, 11 patients developed two episodes, and four patients had three infection episodes during their ICU stay.

Figure 2.

Distribution of nosocomial infection types among intensive care unit trauma patients (n = 65 infection episodes). VAE = Ventilator-associated event; BSI = Bloodstream infection; SSI = Surgical site infection; UTI = Urinary tract infection

Pathogen distribution

Among the 81 isolated organisms, Acinetobacter spp. was the most prevalent (49.4%), followed by Klebsiella spp.(27.7%), Staphylococcus epidermidis (10.8%), Pseudomonas aeruginosa (6%), S. aureus (2.4%), Enterobacter spp.(2.4%), and Escherichia coli (1.2%) [Figure 3]. Gram-negative organisms accounted for majority (approximately 86%) of the isolates, whereas Gram-positive organisms constituted approximately 14% of the isolates. S. epidermidis and S. aureus were the key Gram-positive pathogens, collectively causing approximately 13.2% of the infections.

Figure 3.

Frequency of pathogens isolated from nosocomial infections in intensive care unit trauma patients (n = 81 isolates)

Antibiotic resistance

The analysis of antibiotic resistance patterns revealed alarmingly high resistance rates among both the Gram-negative and Gram-positive isolates [Table 2]. Among the Gram-negative bacteria, Acinetobacter spp. showed complete resistance to meropenem (38/38 isolates), cefepime (34/34), ciprofloxacin (6/6), and ampicillin-sulbactam (3/3). High resistance was also noted for ceftazidime (29/31, 93%) and levofloxacin (25/27, 92%), whereas resistance to amikacin was slightly lower but still substantial (30/34, 88%). Klebsiella spp. showed 100% resistance to cotrimoxazole (11/11), ceftazidime (16/16), ampicillin-sulbactam (2/2), meropenem (19/19), and ciprofloxacin (4/4). The resistance rates to cefepime (18/19, 94%), levofloxacin (11/13, 84%), and amikacin (15/18, 83%) were also high.

Table 2.

Antibiotic resistance of bacteria isolated from nosocomial infections in trauma patients admitted to intensive care units (n=81 isolates)

Antibiotic	Gram-negative bacteria, number of resistant isolates/total isolates (%)					Gram-positive bacteria, number of resistant isolates/total isolates (%)
	Acinetobacter spp., n/N (%)†	Klebsiella spp., n/N (%)	Pseudomonas aeruginosa spp., n/N (%)	Escherichia coli spp. n/N, %)	Enterobacter spp., n/N (%)	Staphylococcus epidermidis spp., n/N (%)	Staphylococcus aureus spp., n/N (%)
Ceftazidime	29/31 (93)	16/16 (100)	2/3 (66)	1/1 (100)	2/2 (100)	-	-
Cefepime	34/34 (100)	18/19 (94)	2/3 (66)	-	1/1 (100)	-	-
Ampicillin-Sulbactam	3/3 (100)	2/2 (100)	-	-	1/1 (100)	-	-
Meropenem	38/38 (100)	19/19 (100)	2/2 (100)	-	1/1 (100)	-	-
Amikacin	30/34 (88)	15/18 (83)	2/3 (66)	-	1/1 (100)	-	-
Tobramycin	-	-	-	-	-	-	-
Gentamicin	-	-	-	-	1/1 (100)	5/7 (71)	1/1 (100)
Ciprofloxacin	6/6 (100)	4/4 (100)	1/1 (100)	1/1 (100)	2/2 (100)	4/5 (80)	-
Levofloxacin	25/27 (92)	11/13 (84)	1/2 (50)	-	-	0/1 (0)	2/2 (100)
Cotrimoxazole	19/27 (70)	11/11 (100)	-	-	1/1 (100)	5/7 (71)	0/1 (0)
Clindamycin	-	-	-	-	-	4/5 (80)	2/2 (100)
Erythromycin	-	-	-	-	-	5/6 (83)	2/2 (100)

^†Data are presented as n/N (%) as the number of resistant isolates/total isolates (%). Resistance percentages were based on the number of isolates tested, as specified in each row

Other Gram-negative pathogens also exhibited similar trends. P. aeruginosa isolates showed 66% resistance to ceftazidime (2/3), cefepime (2/3), and amikacin (2/3), and complete resistance to ciprofloxacin (1/1) and meropenem (2/2). E. coli (n = 1) was fully resistant to ceftazidime and ciprofloxacin (1/1 each). Enterobacter spp. showed 100% resistance to all the tested antibiotics, including ceftazidime (2/2), cefepime (1/1), ampicillin-sulbactam (1/1), gentamicin (1/1), ciprofloxacin (2/2), amikacin (1/1), meropenem (1/1), and cotrimoxazole (1/1).

Among Gram-positive bacteria, S. epidermidis exhibited high resistance to erythromycin (5/6, 83%), clindamycin (4/5, 80%), ciprofloxacin (4/5, 80%), cotrimoxazole (5/7, 71%), and gentamicin (5/7, 71%). However, all the tested isolates were sensitive to levofloxacin (0/1 resistant). S. aureus showed complete resistance to gentamicin (1/1), levofloxacin (2/2), clindamycin (2/2), and erythromycin (2/2), while being fully sensitive to cotrimoxazole (0/1 resistant). Overall, the data underscore a critical concern regarding multidrug resistance among ICU pathogens, particularly Gram-negative bacilli such as Acinetobacter and Klebsiella. No statistically significant associations were observed between the type of infection or isolated pathogen and patient trauma severity, comorbidities, or specific ICU ward (P > 0.05).

DISCUSSION

In this study of trauma patients admitted to the ICU, the most frequent HAI was VAE, which accounted for over half of all infection episodes. The predominant pathogens were Gram-negative bacteria, with Acinetobacter spp. and Klebsiella spp. leading the isolates. Most of these organisms demonstrate extensive multidrug resistance. Successful interventions in similar ICU settings include the implementation of antimicrobial stewardship programs, routine antibiotic de-escalation, ventilator care bundles, and strict adherence to hand hygiene and contact precautions.[21] For example, ICU-based antimicrobial stewardship interventions have been shown to significantly reduce inappropriate antibiotic use and resistance rates, particularly when combined with infection surveillance and staff education.[21] Despite the small sample size, our study offers important insights into the burden and microbiological profile of nosocomial infections in ICU trauma populations, emphasizing the need for strict infection control protocols and antimicrobial stewardships.

The predominance of Acinetobacter spp. and Klebsiella spp. in our ICU setting may be attributed to factors such as the environmental persistence of these organisms, high usage of broad-spectrum antibiotics, and potential lapses in infection control practices. In addition, local antimicrobial prescription patterns and patient factors such as prolonged mechanical ventilation and invasive devices may contribute to their proliferation. In addition, the 100% resistance of Acinetobacter spp. to meropenem observed in our study is alarming and highlights the growing challenge of multidrug resistance in ICU settings. A surveillance study from Iran reported that 95.1% of Acinetobacter isolates were resistant to meropenem, which is consistent with our findings and indicates a nationwide crisis in treating these infections.[22] In addition, global data from the WHO GLASS report indicated similarly high rates of carbapenem-resistant Acinetobacter in many low- and middle-income countries.[23] The widespread use of carbapenems and environmental resilience likely contribute to their dominance in ICU-acquired infections. These data underscore the urgent need for national antimicrobial stewardship programs and stricter infection-control interventions.

The ultimate goal of hospitals is to effectively and efficiently meet the healthcare needs of the community.[24] Patients expect to receive safe, high-quality, and effective care during hospitalization.[24] Despite technological advances and the introduction of new diagnostic and therapeutic methods, the increasing use of invasive procedures and immunosuppressive medications in hospitals has led to an increase in the prevalence of HAIs.[25] A 2022 study by Magill et al. reported that 5.2% of hospitalized patients in the United States had at least one HAI, reflecting a persistent burden despite earlier decline.[26] Similarly, the WHO’s 2022 global report highlighted that seven out of every 100 hospitalized patients in high-income countries and 15 out of every 100 in low- and middle-income countries acquire at least one HAI during their stay.[27]

Several risk factors contribute to the development of nosocomial infections, including age <1 year or more than 65 years, malnutrition, emergency ICU admission, hospitalization longer than 7 days, urinary catheterization, venous and arterial catheterization, suctioning, intubation, surgical procedures, history of previous surgeries, use of immunosuppressive drugs, and comatose status. The urinary tract is most commonly affected by hospital-acquired infections, followed by the respiratory and circulatory system.[28,29,30]

According to the CDC, trauma-related injuries are one of the leading causes of mortality worldwide.[31] In the United States alone, at least 1.7 million HAIs occur annually in the United States, resulting in an estimated economic burden of $9.8 billion.[32] Iran, a developing country, has a high prevalence of trauma-related deaths and complications. Previous studies have shown that nosocomial infections significantly increase mortality rates among trauma patients, with reports suggesting a 12.7-fold increase in the risk of death.[33] Nosocomial infections are therefore recognized as major risk factors for delayed mortality in trauma patients. Moreover, trauma patients are inherently more vulnerable to infections, which can further jeopardize their survival.[33,34,35,36]

In this study, we investigated the prevalence of nosocomial infections among trauma patients admitted to ICUs in Isfahan, and VAE emerged as the most common type of infection. The most frequently isolated pathogens were Acinetobacter and Gram-negative bacteria. Male patients exhibited a higher risk of developing infections; however, there was no statistically significant association between infection occurrence and comorbidities or trauma sites. Several studies across different regions of Iran have explored the epidemiology of hospital-acquired infections. Farzanpoor et al. conducted a 5-year study that reported an overall HAI prevalence of 1.2% across all hospital wards. Respiratory infections were the most common (0.5%), followed by UTI (0.4%), SSI (0.3%), and BSI (0.1%). It is important to note that their study included all hospitalized patients and wards, not specifically trauma patients in ICUs, which distinguishes it from our study.[37]

In another study by Darvishpoor et al., the mean prevalence of HAIs in Torbat Heydariyeh’s 9^th Dey Educational Hospital between 2012 and 2013, the mean prevalence of HAIs was 0.7%. The most frequently isolated organisms were E. coli (9.9%), Klebsiella (7.7%), Gram-negative bacilli (7.7%), Enterobacter (7.7%), and coagulase-positive Staphylococcus (7.7%). SSIs were the most common, followed by pneumonia, UTI, and BSI. They also reported that ICU and orthopedic wards had the highest rates of infection.[38] In a different study by Ghanbari et al. conducted at the Shariati Hospital of Isfahan in 2014, the overall HAI prevalence was reported to be 5.4%. UTIs were the most prevalent, accounting for 72% of cases, followed by BSIs (15.6%), and wound infections (7%). E. coli was the most common pathogen, followed by P. aeruginosa and Enterococcus faecalis. The highest infection rates were observed in internal medicine, ICU, surgery, emergency, and pediatric wards.[39]

Multiple studies, both in Iran and globally, have identified the ICU as the hospital setting with the highest risk of nosocomial infection. This has been demonstrated in studies conducted in Germany, India, Morocco, and the WHO. The higher risk in ICUs is likely due to the more critical condition of patients and their prolonged hospital stays.[40,41,42,43,44] Interestingly, tract infections have been reported as the most common type of hospital-acquired infections, accounting for approximately 40% of all cases. However, our findings contrast with this pattern because VAE is the most prevalent type of infection. This discrepancy may warrant further investigation and could be attributed to differences in hospital procedures and sterilization protocols.[45,46,47,48]

In most Iranian studies, E. coli has been the leading pathogen responsible for HAIs, particularly in general hospital settings and among non-ICU patients.[28,48] However, our study identified Acinetobacter spp. and Klebsiella spp. as predominant organisms. This discrepancy may be attributed to differences in the patient populations. Our cohort consisted exclusively of trauma patients requiring intensive care and invasive support, which are known risk factors for infection by multidrug-resistant nonfermenting Gram-negative bacteria. In addition, ICU-specific factors, such as prolonged mechanical ventilation, higher device utilization, and potential differences in infection control practices, may contribute to this distinct microbial profile.

Our pattern also aligns with the global findings that Gram-negative bacteria are increasingly dominant in ICU settings and are often resistant to multiple antibiotic classes. For example, Blot et al. reported that antimicrobial resistance in ICU patients has significantly increased in recent years, with A. baumannii emerging as one of the most resilient pathogens.[8] Similarly, a study in China observed that respiratory infections in ICUs were the most common nosocomial infections, with a high prevalence of Acinetobacter and S. epidermidis species that were resistant to multiple antibiotics.[47]

This study had several limitations. First, it was conducted at a single tertiary care center, which may limit the generalizability of the findings because of potential institutional differences in ICU structure, infection control practices, and patient characteristics. Second, the relatively small sample size may have reduced statistical power and increased the risk of selection bias. This limited power may have contributed to the lack of statistically significant associations between infection type, pathogen distribution, and patient-or trauma-related characteristics, despite clinically plausible differences. Although all eligible HAI cases were included in the census during the study period, residual confounding and unmeasured variables (e.g., device use and staffing ratios) may have influenced the outcomes. Third, owing to the cross-sectional design, causal relationships between risk factors and infection outcomes cannot be inferred. Finally, some patient-level variables (such as comorbidities) were extracted from the medical records and may reflect reporting bias or documentation inaccuracies. Despite these limitations, we used standardized CDC/NHSN definitions and predefined inclusion criteria to enhance the internal validity. To improve infection control outcomes in ICU settings, future studies should employ multicenter designs with larger sample sizes and prospective data collection. The implementation of standardized interventions, such as ventilator care bundles, catheter-related BSI (CRBSI) prevention protocols, routine environmental sampling, and hand hygiene audits, can help reduce nosocomial infections and improve patient safety in high-risk settings.

CONCLUSION

This study highlights the burden of hospital-acquired infections among ICU trauma patients, with VAEs as the most common infection type, and multidrug-resistant Gram-negative organisms, particularly Acinetobacter spp. and Klebsiella spp., as the leading pathogens. These findings underscore the urgent need for targeted infection control measures, including antimicrobial stewardship programs, ventilator care bundles, and strengthened surveillance systems. In addition, multicenter studies are essential to validate these findings and to inform evidence-based policies aimed at reducing infection-related morbidity and mortality in high-risk trauma populations.

Ethics approval and consent to participate

This study was approved by the Ethics Committee of Isfahan University of Medical Sciences (ethics code: IR. MUI. MED. REC.1399.786). All methods were performed in accordance with the relevant guidelines and regulations. The requirement for informed consent was waived by the Ethics Committee owing to the retrospective nature of the study.

Availability of data and materials

The datasets generated and analyzed during the current study are available from the corresponding author upon reasonable request.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.