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Efficacy and Tolerability of Non-Routine Gastric Residual Volume Monitoring in Mechanically Ventilated Adults
Hui Zhang1, Yan Chen2, Fan Li3
1Department of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
Background:
Patients receiving early enteral nutrition in the intensive care unit (ICU) often undergo gastric residual volume (GRV) monitoring to assess feeding tolerance. Despite guidelines recommending non-routine monitoring, many ICUs continue to perform 4-hourly GRV checks, which may lead to unnecessary feeding interruptions and increased nursing workload.
Aim:
To explore the impact of non-routine monitoring of GRV on feeding intolerance in patients receiving early enteral nutrition.
Study Design:
This was a randomised controlled non-inferiority trial conducted in a tertiary A-level hospital. Patients receiving mechanical ventilation and continuous enteral nutrition were randomly assigned to an intervention group (GRV monitored once at 12 h, then once daily) or a control group (routine 4-hourly monitoring). Feeding intolerance was defined as vomiting or GRV > 200 mL.
Results:
Each group included 52 patients. Feeding intolerance occurred in 36.5% of the intervention group versus 21.2% of controls, with an absolute difference of 15.4% (95% CI -2.0 to +31.6; p = 0.13), indicating a non-significant difference between the two groups. Competing-risk models showed no significant between-group difference (adjusted HR 1.35, 95% CI 0.62 to 2.92; p = 0.45). Higher BMI was associated with lower intolerance risk (HR 0.91 per 1-point increase; p = 0.044), while higher SOFA score increased risk (HR 1.14 per 1-point increase; p = 0.014).
Conclusions:
Reducing GRV monitoring to once daily did not increase the incidence of feeding intolerance.
Relevance To Clinical Practice:
The findings of this study support critical care nurses in reducing gastric residual volume monitoring to once daily, as this does not increase the incidence of feeding intolerance. However, attention should be paid to patients at higher risk of feeding intolerance.
Trial Registration:
This study was registered in the Chinese Clinical Trial Registry (Registration number: ChiCTR2000038245).
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