Nurse Training and ICU Unit Size Associated With Microaspiration Prevention Adherence, Survey Finds

When a patient lies intubated in an intensive care unit, a silent process called microaspiration can pool dangerous secretions in the airway. Endotracheal intubation disrupts normal swallowing, allowing oropharyngeal and subglottic secretions to accumulate above the tracheal cuff. Because the cuff never seals the trachea completely, these microbe-laden secretions gradually seep into the lower airways. The reported incidence of this phenomenon in mechanically ventilated patients reaches as high as 88.9 percent, and it is considered a major pathogenic mechanism behind ventilator-associated pneumonia. In Chinese intensive care units, where ventilator-associated pneumonia affects roughly 30 percent of mechanically ventilated patients with a mortality rate of 11.11 percent, the stakes of preventing this upstream event are considerable. Yet a new multicenter survey from Henan Province suggests that the nursing practices designed to block microaspiration are applied unevenly, and that unit size and nurse training are associated with how consistently those practices are reported.

The study, a cross-sectional survey conducted between December 2024 and February 2025, recruited 510 intensive care nurses across 31 adult ICUs in 17 hospitals in four cities in Henan Province. After excluding 34 questionnaires with identical responses across all items, the researchers analyzed data from 476 nurses. Participants were required to hold a valid registered nurse license, have at least one year of continuous adult ICU experience, and provide informed consent. The questionnaire contained 75 items in three sections: demographic and professional background, current microaspiration-prevention practices, and potential implementation determinants. The practice section covered 22 items across five domains—basic care, cuff management, subglottic suctioning, enteral nutrition, and risk management—each rated on a five-point scale from never to always. The 43 implementation items were informed by the Determinants of Implementation Behaviour Questionnaire, which is grounded in the Theoretical Domains Framework, a widely used model for examining the behavioral and psychological factors that shape how healthcare professionals adopt recommended practices.

The headline result was a mean total adherence score of 77.17 out of a possible 110, equivalent to 70.15 percent of the maximum. Basic care scored highest among the five domains, at 73.6 percent of the maximum item-level score, while risk management scored lowest at 67.2 percent. At the item level, the most frequently reported practices were performing oral care at least twice daily, using a combined oral care approach involving tooth brushing, rinsing, and suctioning, and elevating the head of the bed to 30 to 45 degrees for intubated patients. The weakest items clustered around risk management: continuous risk assessment for microaspiration in high-risk patients, the ability to use or assist with bedside gastric ultrasound to assess gastric residual volume, and the ability to identify patients at high risk of microaspiration. The authors caution that these scores represent self-reported implementation frequency under each nurse’s actual clinical conditions, not verified practice, and that the questionnaire did not capture whether each individual practice was applicable to a given nurse’s patients.

The statistical core of the study was a three-level mixed-effects model that accounted for nurses clustered within 31 ICUs, which were themselves nested within 17 hospitals. After adjusting for bed capacity, age, ICU type, educational level, years of ICU experience, hospital level, and both training exposures, ICU bed capacity showed an overall association with adherence. Compared with nurses in ICUs with fewer than five beds, adjusted adherence scores were significantly lower in units with 10 to 14 beds, 15 to 19 beds, and 20 or more beds, with adjusted differences ranging from roughly 7 to 8.4 points. The 5-to-9-bed group did not differ significantly from the smallest units. The authors emphasize that this category-specific pattern should not be read as a simple linear trend across bed-capacity groups, and they suggest that larger units may face more complex workflows, longer communication chains, less direct supervision, and harder coordination of resources.

Training emerged as the other consistent correlate. Nurses who had received evidence-based practice training scored about 4 points higher on the adjusted adherence scale than those who had not, and nurses trained specifically in microaspiration prevention scored similarly higher. Both associations held in the fully adjusted model, with confidence intervals excluding zero. Educational attainment also mattered: compared with nurses holding a junior college degree or below, those with master’s degrees scored about 6.3 points higher and those with doctoral degrees about 9.2 points higher, while a bachelor’s degree alone was not independently associated with adherence. Older age was associated with lower adherence, with each representative year of age corresponding to a decrease of roughly 0.6 points. ICU type, hospital level, and years of ICU working experience were not independently associated with adherence after adjustment. In bivariate analyses, general and respiratory ICUs had the highest median scores at 89 points, while the emergency ICU had the lowest at 70, but this departmental pattern disappeared after multivariable adjustment.

The implementation-determinant section revealed a striking psychological profile. The three lowest-scoring items concerned near-term intention, prioritization, and professional identity. The single lowest item asked whether the nurse intended to deliver microaspiration prevention according to implementation recommendations in the next three months; it scored 3.10 out of 5, with a large standard deviation of 1.72 indicating substantial variability. The second-lowest item asked whether nurses usually prioritized microaspiration-prevention measures over other routine tasks, scoring 3.21, and the third asked whether delivering such prevention was part of their work as a nurse, scoring 3.29. Interpreted retrospectively through the Theoretical Domains Framework, these items map onto the intentions, goals, and social/professional role and identity domains, suggesting that competing clinical priorities and unclear professional responsibility may be significant barriers in resource-constrained settings.

At the other end of the spectrum, the highest-scoring items reflected practical fit rather than conviction. Nurses agreed most strongly that microaspiration prevention costs little time to deliver (4.19), that it is compatible with daily practice (4.15), and that implementing the recommendations is interesting (3.94). These items were interpreted as relating to innovation characteristics and beliefs about consequences. The authors note that perceived time efficiency and workflow compatibility may be relevant to implementation, and that the relatively high score on interest hints at intrinsic motivation, though the large standard deviation on that item points to wide individual variation. Items concerning management support and colleague helpfulness both scored 3.36, suggesting that organizational and social support deserve further investigation as potential levers for change.

The findings arrive against a backdrop of established bundle-level evidence. A long-term quality-improvement study and a systematic review with meta-analysis have shown that multicomponent ventilator-associated pneumonia prevention bundles can reduce pneumonia incidence and improve related outcomes. However, those studies demonstrate bundle-level effects rather than the independent effectiveness of each component, and evidence on nurses’ adherence to microaspiration-specific practices—targeting the upstream mechanism itself—has remained limited. A previous multicenter survey of 626 ICU nurses in Guangxi found that although 91.7 percent believed microaspiration assessment deserved the same attention as other ICU complications, only 66.0 percent reported actively assessing its occurrence. The present study extends this line of inquiry by examining a broader set of prevention practices alongside individual behavioral and psychological determinants among Chinese ICU nurses.

The authors are careful about the limits of their evidence. The cross-sectional design cannot establish causality, self-reported behavior may be inflated by social desirability despite anonymous administration, and the questionnaire lacked a not-applicable option, meaning clinically appropriate non-performance could not be cleanly separated from true non-adherence. A sensitivity analysis excluding eight condition-specific items supported the bed-capacity pattern and the positive association with evidence-based practice training, but the microaspiration-prevention training coefficient, while still positive, was no longer statistically significant. Convenience sampling through professional networks and head nurses, the restriction to four cities in Henan Province, and the small number of ICUs per bed-capacity category all constrain generalizability and precision. The Theoretical Domains Framework mapping was retrospective rather than prespecified, so domain attributions are exploratory. The authors frame their recommendations—structured continuing education, clearer delineation of nursing responsibilities, workflow integration, and targeted managerial attention in larger units—as priorities for further evaluation rather than proven interventions, and they call for prospective, theory-driven studies with broader geographic coverage and item-level applicability data.

Subject of Research: ICU nurses' self-reported adherence to microaspiration-prevention practices and its implementation determinants

Article Title: Intensive Care Nurses' Self‐Reported Adherence to Evidence‐Informed Microaspiration‐Prevention Practices and Potential Implementation Determinants: A Multicenter Cross‐Sectional Study

Article References: Pei, Y., Fan, S., & Shi, X. (2026). Intensive Care Nurses' Self‐Reported Adherence to Evidence‐Informed Microaspiration‐Prevention Practices and Potential Implementation Determinants: A Multicenter Cross‐Sectional Study. Nursing Open, 13(10), Article e70914. https://doi.org/10.1002/nop2.70914

Image Credits: AI Generated

DOI: 10.1002/nop2.70914

Keywords: microaspiration, ventilator-associated pneumonia, intensive care nursing, adherence, Theoretical Domains Framework, implementation determinants, cross-sectional study, ICU bed capacity, nurse training, evidence-based practice, oral care, subglottic suctioning