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.

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

BACKGROUND: The assessment of residual gastric volume is common practice in critical care units. However, the effects and safety of discarding or returning gastric aspirates remain uncertain. Therefore, we aimed to evaluate the role of discarding or returning gastric aspirates on the gastric residual volumes in critically ill patients.
METHODS: A comprehensive, systematic meta-analysis of randomized controlled trials (RCTs) on the efficacy and safety of discarding or returning gastric aspirates in critical ill patients was performed. Studies were identified by searching Pubmed and other databases (from inception to 31 Sept 2018). Summary odd ratios (ORs) or mean differences (MDs) with 95% confidence intervals were calculated using fixed- or random-effects model for outcome assessment.
RESULTS: Four RCTs, with a total number of 314 adult patients, were included in the analysis. No significant differences were found in the 48th hour residual volume (MD = 8.89, 95% CI: 11.97 to 29.74), the average potassium level (MD = 0.00, 95% CI: - 0.16 to 0.16), the episodes of gastric emptying delay (OR = 0.98, 95% CI: 0.35 to 2.80), the incidence of aspiration pneumonia (OR = 0.93, 95% CI: 0.14 to 6.17), the episodes of nausea or vomiting (OR = 0.53, 95% CI: 0.07 to 4.13) and diarrhea (OR = 0.99, 95% CI: 0.58 to 1.70).
CONCLUSIONS: No evidence confirms that returning residual gastric aspirates provides more benefits than discarding them without increasing potential complications. Rigorously designed, multi-center, large-sample randomized controlled trials must be further conducted to validate the role of discarding or returning residual gastric aspirates.

OBJECTIVE: To observe the clinical therapeutic effect of acupuncture of Huatuo Jiaji (EX-B2) in the treatment of gastrointestinal dysfunction in sepsis patients, aiming at providing new clinical approach and evidence for improving septic gastrointestinal activity.
METHODS: A total of 40 patients with septic gastrointestinal dysfunction who met our inclusive criteria were randomly divided into control group and treatment group (n＝20 cases in each). Patients in the control group received routine treatment of nasogastric mosapride citrate (5 mg/time, three times a day) and tifidobacterium triple viable capsules (420 mg, twice a day), intravenous infusion of omeprazole (40 mg, twice a day), rational dose of antibiotics, maintenance treatment of functions of the heart, lung, brain, kidney and other important organs and water electrolyte balance, as well as symptomatic treatment. Patients of the treatment group were treated by acupuncture of EX-B2 on the basis of routine treatment mentioned above in the control group. The acupuncture needle was inserted into EX-B2, twirled for a while and retained for 30 min, once a day for 10 successive days. The acute physiology and chronic health evaluation (APACHE II) score was given according to Knaus and colleagues\' method, the intra-abdominal pressure was detected by using a manometer which was connected to an inserted canal in the urinary bladder, and the intragatric residul volume detected by using an injection syriange pumping via a nasal feeding tube.
RESULTS: After the treatment, the APACHE II score, intra-abdominal pressure and intragastric residual volume on day 10 were significantly decreased in both groups in comparison with their own pre-treatment (P<0.05), while the borborygmus levels on day 10 were considerably increased in both groups relevant to their own pre-treatment (P<0.05). The APACHE II scores, intra-abdominal pressure and intragastric residual volume on day 3, 6 and 10 were significantly lower in the treatment group than those in the control group (P<0.05), whereas the borborygmus levels at the 3rd , 6th and 10th day in the treatment group were apparently higher than those of the control group (P<0.05)．.
CONCLUSIONS: Acupuncture stimulation of EX-B2 has a good curative effect in improving gastrointestinal dysfunction in sepsis patients.

BACKGROUND: Monitoring gastric residual volume has been a common practice in intensive care patients receiving enteral feeding worldwide. Recent studies though, have challenged the reliability and necessity of this routine monitoring process. Several studies even reported improvements in the delivery of enteral feeding without monitoring gastric residual volume, while incurring no additional adverse events. However, the benefit of monitoring gastric residual volume remains controversial in intensive care patients.
OBJECTIVE: The aim of this review is to identify the effects of not monitoring gastric residual volume in intensive care patients through a meta-analysis of the data pooled from published studies that meet our inclusion criteria.
METHODS: A systematic review DATA SOURCES: An electronic search of Embase, Pubmed, and the Cochrane Library was completed up to April 2018. The data included basic population characteristics, related complications, mortality, duration of mechanical ventilation and intensive care unit length of stay.
METHODS: Eligibility and methodological quality of the studies were assessed by two researchers independently according to the Joanna Briggs Institute guidelines. The Review Manager Software was used to calculate the pooled risk ratio (RR), weighted mean difference, and the corresponding 95% confidential interval (95% CI). Sensitivity analyses were done by excluding each study. Publication bias analyses were conducted to avoid the exaggerated effect of the overall estimates.
RESULTS: Five studies involving 998 patients were included in this meta-analysis. Compared with monitoring gastric residual volume, not monitoring gastric residual volume decreased the rate of feeding intolerance in critically ill patients (RR = 0.61, 95%CI 0.51-0.72), and did not result in an increment in the rate of mortality (RR = 0.97, 95%CI 0.73-1.29, P = 0.84) or the rate of ventilator-associated pneumonia (RR = 1.03, 95%CI 0.74-1.44, P = 0.85). There were also no differences in the duration of mechanical ventilation (MD = 0.09, 95%CI, -0.99 to 1.16, P = 0.88) or intensive care unit length of stay (MD=-0.18, 95%CI, -1.52 to 1.17, P = 0.79).
CONCLUSIONS: Except for an increased risk of vomiting, the absence of monitoring gastric residual volume was not inferior to routine gastric residual volume monitoring in terms of feeding intolerance development, mortality, and ventilator-associated pneumonia in intensive care patients. There is encouraging evidence that not measuring gastric residual volume does not induce additional harm to the patients. More multicenter, randomized clinical trials are required to verify these findings.

Surgical patients are asked to fast for a sufficient duration to ensure that the amount of residual liquid in the stomach is within the safe range, thereby reducing the risk of gastric reflux perioperatively. The authors hypothesized that subjective hunger numerical rating scale (NRS) score could also help assess the process of gastric emptying and determine the amount of fluid remaining in the stomach.
The current study consisted of healthy volunteers recruited by advertisement and mutual introduction. Participants were asked to rate their subjective hunger feeling every 30 min after oral administration of 8 mL/kg carbohydrate nutrient solution that contained 10% maltodextrin and 2.5% sucrose. Consecutively, the gastric residual fluid was measured by magnetic resonance imagining (MRI). The Spearman\'s correlation coefficient, the ROC curves and the stepwise regression were used to analyze the predictive value of NRS for the gastric emptying process.
The cohort consisted of 29 healthy volunteers enrolled in this study. The area under ROC curves estimated by the NRS score for the gastric residual volume of 2 mL/kg, 1 mL/kg, and 0.5 mL/kg were AUC2.0 = 0.78, AUC1.0 = 0.76, and AUC0.5 = 0.72, respectively. The correlation coefficient between the NRS score and the residual liquid in the stomach was -0.57 (P < 0.01). The correlation coefficient between the increase of the NRS score and the decrease of gastric liquid residual volume was 0.46 (P < 0.01). The standardized estimate of NRS score for the residual volume was -0.18 (P < 0.01) and the standardized estimate of fasting time was -0.73 (P < 0.01).
The subjective hunger NRS score can not accurately predict the gastric residual volume, but it can provide a reference for clinicians to judge the gastric emptying process and it should be used as a second check after oral intake of clear fluids before surgery according to the new fasting protocol.

To investigate the accuracy and feasibility of Brix value on monitoring gastric residual volume (GRV) in patients with enteral nutrition. Fifty patients with enteral nutrition via nasogastric tube were enrolled. The GRV was measured by both ultrasonography and Brix value. The results were compared according to the methods. The Pearson correlation coefficients showed that GRV measured by these two ways was positively correlated (r=0.986, P<0.05). Moreover paired sample t-test showed that the discrepancy was not statistically significant (P>0.05) between different measurements. The consistency was analyzed by Bland-Altman graph, showing that the two measurements were consistent. Brix value is recommended to measure GRV due to its convenience and easy operation.
探讨白利度计监测肠内营养患者胃残余量（GRV）的可行性及准确性。选取50例经鼻胃管行肠内营养治疗的患者，分别用超声和白利度计测量GRV，比较两者测量结果的一致性。配对样本t检验显示两种测量方法结果的差异无统计学意义（P>0.05），Pearson相关分析显示两种测量方式结果呈正相关（r=0.986，P<0.05），Bland-Altman图分析结果显示两种测量结果具有一致性。研究结果初步提示利用白利度计测量GRV简便易行，可在临床推广。.

Objective: To explore the effect of bedside ultrasound in measuring gastric residual volume in neurosurgical critical patients with enteral nutrition support. Method: From March to August 2016, 70 critically neurological patients with continues enteral nutrition who admitted in Intensive Care Unit (ICU) were randomized into two groups. The observation group applied the bedside ultrasound monitoring gastric residual volume every day to guide the implementation of enteral nutrition. The control group used syringes withdrawing every 8 hours to measure the gastric residual volume. Results: There was no statistically significant difference in the incidence of complications include regurgitation and aspiration in this two group patients (P=0.356; P=1.000), while the times of interrupting enteral nutrition was lower in the observation group(25.7% vs 5.7%, 74.3% vs 94.3%, P=0.045), the length of target feeding time and the length of ICU stay, the operation time was shortened, with a statistically significant difference[(2.37±0.69) d vs (3.49±0.74) d, P=0.028; (8.52±5.45) d vs (6.40±2.71) d, P=0.022; (58.29±11.22)s vs (67.60±7.05) s, P=0.000]. Conclusion: The application of bedside ultrasound to measure gastric residual volume can be a scientific method to guide enteral nutrition in neurosurgical critical patients, which can reduce the times of interrupting enteral nutrition and shorten the length of target feeding time and ICU length of stay, reduce the workload of nurses.
目的： 探讨床旁超声监测胃残余量在神经外科重症患者肠内营养中的应用效果。 方法： 2016年3至8月中南大学湘雅医院重症医学科(ICU)的70例行持续肠内营养的神经重症患者，数字表法随机分为2组，观察组采取床旁超声监测胃残余量，每天监测1次，指导肠内营养实施；对照组采用注射器回抽法每8小时监测胃残余量进而调整肠内营养方案。 结果： 两组患者在胃内容物反流、误吸等并发症发生率方面差异无统计学意义(P＝0.356；P＝1.000)，观察组肠内营养中断率低于对照组(25.7%比5.7%，74.3%比94.3%，P＝0.045)，观察组肠内营养达到目标喂养量时间、住ICU时间、操作时间较对照组明显缩短[(2.37±0.69) d比(3.49±0.74) d，P＝0.028；(8.52±5.45) d比(6.40±2.71) d，P＝0.022；(58.29±11.22) s比(67.60±7.05) s，P＝0.000]。 结论： 床旁超声监测胃残余量可以更科学地指导神经外科重症患者肠内营养方案，减少肠内营养中断率，更快地达到目标喂养量，缩短ICU住院时间，减轻了护士的工作量。.

It is routine practice in most neonatal intensive care units to measure the volume and color of gastric residuals (GRs) prior to enteral bolus feedings in preterm very low birth weight infants. However, there is paucity of evidence supporting the routine use of this technique. Moreover, owing to the lack of uniform standards in the management of GRs, wide variations exist as to what constitutes significant GR volume, the importance of GR color and frequency of GR evaluation, and the color or volume standards that dictate discarding or returning GRs. The presence of large GR volumes or green-colored residuals prior to feeding often prompts subsequent feedings to be withheld or reduced because of possible necrotizing enterocolitis resulting in delays in enteral feeding. Cessation or delays in enteral feeding may result in extrauterine growth restriction, a known risk factor for poor neurodevelopmental and growth outcomes in preterm very low birth weight infants. Although some neonatal intensive care units are abandoning the practice of routine GR evaluation, little evidence exists to support the discontinuation or continuation of this practice. This review summarizes the current state of GR evaluation and underlines the need for a scientific basis to either support or refute the routine evaluation of GRs.