This study aimed to clarify the influencing factors of MDRO infection in Neuro-ICU, and further construct predict models according to the influencing factors. A total of 297 patients admitted in Neuro-ICU were included in this study, our analysis identified risk factors for MDRO infection, and we developed predictive models using these risk factors.
Our study found that Acinetobacter baumannii, Klebsiella pneumoniae, and Pesudomonas pyocyaneum were the most common pathogens in Neuro-ICU. Recent study showed that Acinetobacter baumannii was found as most frequent bacteria16,17. Among nosocomial infection and colonization, 76% of the bacterial infections were due to Gram-negative bacteria. A. baumannii, Enterobacteriaceae species and P. aeruginosa strains were the main isolated bacteria12. Yang et al.18 also reported that gram negative (GN) bacteria were more common than gram positive (GP) bacteria predominated in central nervous system (CNS) infections, and our study was a little different from previous research results. Pseudomonas pyocyaneum was found as one of the main bacteria in Neuro-ICU. Our results showed that the incidence of MRSA was low, this was similar to the research results of El Mekes et al.12. There are many studies related to ICU MDRO infection rate, and the results have large value fluctuation range, a Chinese study stated MDRO prevalence rate on admission in ICU was 30.5%19.
The present study found that MDRO infections were not uncommon in Neuro-ICU, although this study did not clarify the specific MDRO infection rate, among the study subjects included, the number of patients infected or colonized with MDRO has exceeded 44%, which is extremely high. However, this data did not represent the overall situation of Neuro-ICU. The subjects of our study were patients who entered the ICU and were transferred out. Some patients had been transferred to other hospitals or died during the ICU hospitalization process, so in this study we could not calculate the exact infection rate. However, there is still insufficient evidence for the MDRO infection rate in the Neuro ICU, and more studies are needed to confirm it.
Our study resulted in good predictive models with accuracies of 86.3% using logistic regression. In our study, we found that tracheal intubation, artery blood pressure monitoring, fever, antibiotics, pneumonia are significant predictors for MDRO infection. The use of antibiotics (OR: 8.064) was the most important factor in MDRO infection. In the current state of knowledge, there are few predictive models of MDROs infections in neuro-intensive care units. Minhas et al.20 modeled prediction through decision trees, and our predictive efficacy is similar to this study. Our study differed significantly from another Chinese study21, which examined a model to predict pulmonary infection of multidrug-resistant Acinetobacter baumannii in Neuro-ICU. This may be because we pooled and analyzed a variety of infections rather than pulmonary infection in our study.
The amount of antibiotic use of severe patients is significantly higher than those of ordinary ward. Due to the resistance or infection, antibiotics are often used in combination. It was found that antibiotics and combination of antibiotics are related to MDRO infection in univariate analysis. However, only antibiotic therapy is an independent risk factor of MDRO infection in the multiple logistic regression model. In Neuro-ICU, the majority patient’s primary disease types are traumatic brain injury or stroke, and the pneumonia incidence of two diseases is high22,23. Using mechanical ventilation will aggravate the incidence of pneumonia24.
The use of antibiotics to treat pneumonia is prone to the occurrence and propagation of multi-drug resistant organism25,26,27. A Meta-analysis has clearly been applying antibiotics in advance to risk factors for MDRO infection28. Our research further verified this view. In order to increase the cure rate of multi-drug bacteria, medical staff tend to use antibiotics to enhance the utility of drugs27. It may exacerbate this process. In addition, in this study, fever was also one of the risk factors of MDRO infection, critically ill patients may have a variety of reasons, and fever may be caused by patient’s pneumonia. Among the patients with MDRO infection or planting, 89.31% of patients had pneumonia, while non-MDRO patients were also as high as 56.02%.
Recent studies have shown that the severity of trauma does not affect the incidence of MDRO, the incidence of MDRO in severely injured patients is lower than in ICU29,30,31. The type of admission and disease can indicate the severity of patients, in our results, GCS scores cannot ultimately predict MDRO infection, so our research indicates that MDRO infection is not associated with the severity of disease, this may be caused by autoimmune and early application of antibiotics in patients with acute trauma32.
The results for risk factors were consistent with previous studies in the use of invasive operation24,33,34. In our study, persistent artery blood pressure monitoring and tracheal intubation were two invasive appliances associated with MDRO infection, such invasive operations destroy normal physiological integrity and local immune function. Our research results were different from the past. In the past, urinary tube and feeding tubes were the main indwelling instruments of MDRO infection34,35. Due to the particularity of neurological patients, almost all patients will remain in these two types of piping, so we did not incorporate these two invasive operations.
Furthermore, we found an association between positive MDRO and albumin level, there is a literature pointed out that the lower the serum albumin level, the higher the risk of patient infection36, our research further verified this conclusion. The average age of the patients included in our study was older, and both the patients themselves and the disease caused malnutrition and hypoproteinemia. Despite the study showed allogenic blood transfusions cause immune modulation and have a negative influence on the immune system and may result in increased infections with MDRO37. However, blood transfusion still cannot be used as a predictive variable, although patients with anemia or low nutritious states are worthy of attention, because this type of patient is a high-risk population of MDRO infection.
However, in our study, there were no correlation between the gender, age, medical insurance with MDRO infection. There were many studies had shown that age and gender were not associated with acquired MDRO38,39. A recent research indicated MDRO that infections were numerically associated with the female sex, greater age, and comorbidities40. These factors may require more research to further confirm the correlation.
Future clinical practice should reinforce multidisciplinary coordination so that physicians, pharmacists, and nurses play a more active role in patient care. The screening of patients for multidrug-resistant bacteria in the neurologic intensive care unit should be a routine part of the treatment of patients after admission. In the process of stepping and standardizing the medication regimen of patients, pharmacists should serve as a guide. Physicians and pharmacists will work together in the future to pursue and develop therapeutic medications41,42,43. Nurses are essential components of clinical practice and should play a full role in preventing MDROs and managing them on a daily basis. A high incidence of MDROs in Neuro-ICU makes multidisciplinary work necessary for effective prevention and management of MDRO infections.
There were several limitations in our study. First, this was a retrospective study of a single center, the researchers only collected patient data in a tertiary, a hospital in one province, and the data cannot represent the actual situation in the region or the whole country, and there may be bias. Second, there were less research samples, compared with the comprehensive ICU, Neuro-ICU has a smaller patient population, and the researchers only collected data for the past two years. Finally, although there was established a predictive model based on risk factors, there was no further verification of prediction model, and the impact of the risk prediction model on the actual incidence of MDRO infection in Neuro-ICU patients was not investigated.