Gastric residual volume measurement in the intensive care unit: an international survey reporting nursing practice

Gastric residual volume monitoring practices in UK intensive care units: A web-based survey

Background and aim

Monitoring of gastric residual volume (GRV) to assess for enteral feeding intolerance is common practice in the intensive care unit (ICU) setting; however, evidence to support the practice is lacking. The aim of this study was: (i) to gain a perspective of current practice in adult ICUs in the UK around enteral feeding and monitoring of GRV, (ii) to characterise the threshold value used for a high GRV in clinical practice, (iii) to describe the impact of GRV monitoring on enteral feeding provision and (iv) to inform future research into the clinical value of GRV measurement in the adult ICU population.

Methods

A web-based survey was sent to all UK adult ICUs. The survey consisted of questions pertaining to (i) nutritional assessment and enteral feeding practices, (ii) enteral feeding intolerance and GRV monitoring and (iii) management of raised GRV.

Results

Responses were received from 101 units. Ninety-eight percent of units reported routinely measuring GRV, with 86% of ICUs using GRV to define enteral feeding intolerance. Threshold values for a high GRV varied from 200 to 1000 ml with frequency of measurement also differing greatly from 2 to 12 hourly. Initiation of pro-kinetic medication was the most common treatment for a high GRV. Fifty-two percent of respondents stated that volume of GRV would influence their decision to stop enteral feeds a lot or very much. Only 28% of units stated that they had guidelines for the technique for monitoring GRV.

Conclusions

Measurement of GRV is the most common method of determining enteral feeding intolerance in adult ICUs in the UK. The practice continues despite evidence of poor validity and reproducibility of this measurement. Further research should be undertaken into the benefit of ongoing GRV measurements in the adult ICU population and alternative markers of enteral feeding intolerance.

Is monitoring of gastric residual volume for critically ill patients with enteral nutrition necessary? A meta-analysis and systematic review

BACKGROUND

There are many controversies over the necessity of monitoring gastric residual volume in the nursing care of enteral nutrition. We aimed to conduct an updated meta-analysis to evaluate the effects of monitoring or not monitoring gastric residual volume on patients' outcomes and complications.

METHODS

We searched the Cochrane Library database to 15 April 2021 for randomized controlled trials (RCTs) on the effects of gastric residual volume and no gastric residual volume monitoring. Review Manager software was used for data analysis.

RESULTS

A total of seven RCTs involving 1240 enteral nutrition patients were included. Gastric residual volume monitoring was associated with reduced incidence of vomiting (OR2.33, 95% CI:1.68-3.24), whereas no gastric residual volume monitoring was associated with reduced incidence of unnecessary interruptions of enteral nutrition (OR0.38,95% CI:0.26-0.55). There were no significant differences on the incidence of abdominal distention (OR1.87, 95% CI:0.82-4.28), diarrhoea (OR1.03,95% CI:0.74-1.43), VAP (OR0.83, 95%CI:0.37-1.89), duration of mechanical ventilation (MD -0.06,95% CI:-1.22-1.10), length of ICU stay (MD -1.33, 95% CI:-3.58-0.91) and mortality (OR0.90,95% CI:0.61-1.34).

CONCLUSIONS

Not monitoring gastric residual volume is associated with reduced unnecessary interruptions of enteral nutrition related to inadequate feeding and increased risk of vomiting.

Effects of ultrasound monitoring of gastric residual volume on feeding complications, caloric intake and prognosis of patients with severe mechanical ventilation

BACKGROUND

Monitoring of gastric residual is an important approach for assessing gastric emptying in patients with mechanical ventilation. By monitoring gastric contents, the enteral nutrition scheme can be adjusted in time to ensure feeding safety.

AIM

To investigate the effects of ultrasound monitoring on the incidence of feeding complications, daily caloric intake and prognosis of patients with severe mechanical ventilation. To analyze the clinical significance of ultrasound monitoring of gastric residual volume (GRV) up to 250 mL to provide a theoretical basis for clinical practice.

METHODS

Patients admitted to the department of emergency medicine of the Affiliated Hospital of Nantong University from January 2018 to June 2022 who received invasive mechanical ventilation and continuous enteral nutrition support within 24-48 h after admission were enrolled in this study. Medical records for patients within 7 d of hospitalization were retrospectively analyzed to compare the incidence of feeding complications, daily caloric intake and clinical prognosis between patients with gastric residual ≥ 250 mL and < 250 mL, as monitored by ultrasound on the third day.

RESULTS

A total of 513 patients were enrolled in this study. Incidences of abdominal distension, diarrhea, and vomiting in the < 250 mL and ≥ 250 mL groups were: 18.4% vs 21.0%, 23.9% vs 32.3% and 4.0% vs 6.5%, respectively; mortality rates were 20.8% vs 22.65%; mechanical ventilation durations were 18.30 d vs 17.56 d while lengths of stay in the intensive care units (ICU) were 19.87 d vs 19.19 ± 5.19 d. Differences in the above factors between groups were not significant. Gastric residual ≥ 250 mL was not an independent risk factor for death and prolonged ICU stay. However, target feeding time of patients in the ≥ 250 mL group was longer than that of patients in the ≥ 250 mL group, and caloric intake (22.0, 23.6, 24.8, 25.3 kcal/kg/d) for patients in the ≥ 250 mL group from the 4^th day to the 7^th day of hospitalization was lower than that of patients in the ≥ 250 mL group (23.2, 24.8, 25.7, 25.8 kcal/kg/d). On the 4^th day (Z = 4.324, P = 0.013), on the 5^th day (Z = 3.376, P = 0.033), while on the 6^th day (Z = 3.098, P = 0.04), the differences were statistically significant.

CONCLUSION

The use of ultrasound to monitor GRV and undertaking clinical interventions when the monitoring value is ≥ 250 mL has no significant effects on incidences of feeding complications and clinical prognostic outcomes, however, it significantly prolongs the time to reach target feeding, reduces the daily intake of calories during ICU hospitalization, and increases the risk of insufficient nutrition of patients. The accuracy and necessity of monitoring gastric remnants and monitoring frequencies should be investigated further.

Prevalence and risk factors of enteral nutrition intolerance in intensive care unit patients: a retrospective study

BACKGROUND

Feeding intolerance (FI) among intensive care unit (ICU) patients undergoing early continuous enteral nutrition (EN) is related to poor outcomes. This study aimed to explore the prevalence and risk factors of FI in ICU patients.

METHODS

We retrospectively enrolled 1057 patients who received early continuous EN via a nasogastric tube between January 2014 and August 2019. The prevalence of FI during the first 7 days of ICU stay was calculated, and the risk factors were investigated using multivariate logistic regression analysis.

RESULTS

The prevalence of FI during the first 7 days of ICU stay was 10.95%. FI occurred in 159 of 1057 (15.04%) patients on ICU day 2, 114 of 977 (11.67%) patients on ICU day 3, and 86 of 715 (12.03%) patients on ICU day 7. Mechanical ventilation (MV) (odds ratio [OR]: 1.928, 95% confidence interval [CI]: 1.064-3.493, P  = 0.03) was an independent risk factor for FI defined by a gastric residual volume (GRV) of 200 mL and/or vomiting, and acute renal failure (OR: 3.445, 95% CI: 1.115-10.707, P  = 0.032) was an independent risk factor of FI defined by a GRV of 500 mL and/or vomiting. Continuous renal replacement therapy (CRRT) was an independent predictor regardless of the FI defined by a GRV of 200 mL (OR: 2.064, 95% CI: 1.233-3.456, P  = 0.006) or 500 mL (OR: 6.199, 95% CI: 2.108-18.228, P  = 0.001) in the ICU patients.

CONCLUSIONS

FI occurs frequently in early ICU days, especially in patients receiving MV and CRRT. However, further investigation of a consensus definition of FI and risk factors is still warranted in future studies.

Comparison of Two Different Threshold Values for the Measurement of Gastric Residual Volume on Enteral Nutrition Support in the Neurocritically Ill Patients

Background

Although recommendations on gastric residual volume (GRV) have been applied to the clinical practice of patients who are intubated, evidence-based data about the GRV of patients who are neurocritically ill are still lacking. We conducted this study to investigate the safety of increased GRV in patients who are neurocritically ill on enteral nutrition (EN) support.

Methods

Patients who are neurocritically ill feeding through intragastric enteral tubes were recruited consecutively between July 2018 and June 2021. Patients were divided into a control group (GRV 100 ml) and a study group (GRV 200 ml). Demographic data, admission diagnosis, and severity scores were collected from the patient medical records. The frequency of diet volume ratio (diet received/diet prescribed), the incidence of gastrointestinal complications, and outcome variables were evaluated.

Results

There were 344 patients enrolled, of whom 197 had mechanical ventilation support. High GRV events in the control group were more frequent than those in the study group (38.1 vs. 22.8%, p = 0.002). The total gastrointestinal complication rate did not differ significantly between the two groups (study group: 61.1%, 102/167 vs. control group: 67.9%, 114/168). In the study group, two patients had aspiration (1.2 vs. 0%, p = 0.245). The study group showed a superior diet volume ratio, but the difference was not significant. The outcomes of the study group were slightly better than those of the control group; however, no significant differences were observed between the two groups concerning the length of stay in the neurointensive care unit (19.5 days vs. 25.3 days) and mortality (10.8 vs. 14.9%) at discharge.

Conclusion

Our results suggest that 200 ml may be a safe normal limit for GRV in patients who are neurocritically ill.

Does ultrasonographic assessment of gastric antrum correlate with gastric residual volume in critically ill patients? A prospective observational study

This study aimed to evaluate the relationship between ultrasonographic gastric antral measurements and aspirated gastric residual volume (GRV) in mechanically ventilated critically ill patients receiving enteral nutrition (EN). This prospective observational study included 56 enterally-fed critically ill patients in one-year period. All imaging procedures were done at 30-degree head-of-bed elevation and supine position on epigastric region of abdomen with 2.5-6 MHz convex-array probe just before routine GRV aspiration. The antral cross-sectional area (CSA) was calculated by measuring the anteroposterior (dAP) and craniocaudal diameters (dCC) of the gastric antrum. Total 283 ultrasonographic gastric antrum imaging procedures were done. In only eight (2.82%) attempts, the antrum could not be visualized due to inhibition from intra-gastric air or gas in the surrounding intestinal lumen. The calculated mean antral CSA was 568.15 ± 348.37 mm² (103.43-2,846.30). The antral CSA correlated significantly with aspirated GRV, and the antral CSA increased linearly with increasing aspirated GRV (R² = 0.73, p < 0.0001). In Receiver operating characteristic (ROC) analysis of antral CSA ≥ 920 mm² (mean + 1*SD) for estimating aspirated GRV, the area under the curve (AUC) was 0.848 (95% CI, 0.76 ~ 0.93) (p < 0.0001), and ROC analysis of antral CSA to discriminate aspirated GRV ≥ 250 mL showed a significant relation (AUC = 0.969, 95% CI 0.94 ~ 0.99, p < 0.0001). Ultrasonographic measurement of gastric antral CSA is an easy and reliable bedside procedure to estimate GRV in critically ill patients receiving EN in 30-degree head-of-bed elevation and supine position. Trial registration number: NCT04413474, date of registration: June 17, 2020, retrospectively registered.