Intolerance to intragastric enteral nutrition in critically ill patients: complications and management

Serum potassium levels as an independent predictor of unplanned enteral nutrition discontinuation in older adults with gastroesophageal reflux disease

BACKGROUND & AIMS

Enteral nutrition in older adults is often associated with intolerance, a phenomenon not well-understood in the context of gastroesophageal reflux disease (GERD). This observational study aimed to evaluate serum potassium levels as an independent prognostic factor for unplanned enteral nutrition discontinuation in older adults with GERD.

METHODS

We conducted a retrospective analysis of 213 consecutive patients with GERD who received enteral nutrition at our institution from April 2018 to March 2023. The dietary assessment involved extracting relevant nutritional information from the patients' medical records. The incidence of enteral nutrition discontinuation due to complications was monitored over a 30-day period after initiation.

RESULTS

Patients were categorized into three groups based on initial serum potassium levels: low (<4.0 mmol/L), intermediate (4.0-4.5 mmol/L), and high (≥4.5 mmol/L). During the follow-up, 35 % of patients experienced events leading to the discontinuation of enteral nutrition. Higher potassium levels correlated with an increased risk of unplanned discontinuation of enteral nutrition (log-rank P = 0.002). Multivariate Cox proportional hazards analysis identified serum potassium level as an independent predictor of unplanned discontinuation (hazard ratio: 1.700 [95 % confidence interval: 1.100-2.627] per 1 mmol/L, P = 0.017).

CONCLUSIONS

Serum potassium level is a robust independent predictor of unplanned enteral nutrition discontinuation in older adults with GERD. Our findings suggest that monitoring and adjusting potassium levels may be essential for improving outcomes in this vulnerable population.

Effect of abdominal massage on feeding intolerance in patients receiving enteral nutrition: A systematic review and meta‐analysis

AIM

This study aimed to evaluate the effect of abdominal massage (AM) on feeding intolerance (FI) in patients receiving enteral nutrition (EN).

DESIGN

A systematic review and meta-analysis.

METHODS

We searched seven electronic databases to September 2021. STATA and RevMan were used to analyse the data.

RESULTS

Eleven studies were included. The results revealed that AM could significantly reduce gastric residual volume and abdominal circumference difference, and reduce the incidence of gastric retention, vomiting, abdominal distention (all p < 0.001), diarrhoea (p = 0.02) and constipation (p = 0.002) in the experimental group. One study reported the incidence of aspiration in the control group was higher, but this was not statistically significant (p = 0.07). The meta-regression analysis showed there was a statistically significant correlation between intervention personnel and gastric residual volume (p = 0.035).

CONCLUSION

AM could reduce the amount and incidence of gastric retention and the changes in abdominal circumference, and significantly reduce the incidence of gastrointestinal symptoms, without increasing the incidence of aspiration for EN patients. No Patient or Public Contribution.

The effect of dietary fiber on gut barrier function, gut microbiota, short-chain fatty acids, inflammation and clinical outcomes in critically ill patients: A systematic review and meta-analysis

BACKGROUND

Although some studies have explored the relationships between dietary fiber (DF) supplement and gut barrier function, changes of gut microbiota and other clinical outcomes in critically ill patients, the results from different studies were not consistent.

OBJECTIVE

The purpose of this study was to explore the effect of dietary fiber on gut barrier function, gut microbiota, short-chain fatty acids (SCFAs), inflammation and clinical outcomes in critically ill patients.

METHODS

A search was performed through PubMed, Embase, the Cochrane Central Register of Clinical Trials, Web of Science and EBSCO-host that includes Health Sciences Research from inception to July 12, 2021. Data were pooled using fixed effects model for low heterogeneity and random effects model for high heterogeneity. Data were expressed as mean difference (MD) or odds ratio (OR) with confidence interval.

RESULTS

A total of 21 studies involving 2084 critically ill patients were included. The results showed that there was a significant reduction in intestinal permeability demonstrated by lactulose/rhamnose ratio (MD:-0.04; 95%CI:-0.08, -0.00; P = 0.03) on day 8 in DF supplement group. Three studies reported the relative abundance (RA) of gut microbiota and the results showed the RA of some SCFAs producers increased higher in DF supplement group. There was a significant decrease in C-reactive protein on day 14 (MD:-36.66; 95%CI:-44.40, -28.93; P<0.001) and the duration of hospital stay (MD:-3.16; 95%CI:-5.82, -0.49; P<0.05) after DF supplement. There were no significant differences on SCFAs levels, the duration of mechanical ventilation and mortality between the two groups. However, in subgroup analysis, the results indicated there was a significant reduction on the duration of mechanical ventilation in fiber combined probiotic group (MD:-13; 95%CI:-19.69, -6.31; P<0.001). Besides, significant decreases in the duration of hospital stay and risk of mortality were seen in the subgroups with fiber supplementary dose ≥20 g/d (MD:-5.62; 95%CI: -8.04, -3.21; P<0.0001; OR: 0.18, 95%CI: 0.06, 0.57, P = 0.004), as well as in medical ICU (MD:-4.77; 95%CI: -7.48, -2.07; P<0.01; OR: 0.13; 95%CI: 0.03, 0.65; P<0.05).

CONCLUSIONS

Dietary fiber may improve the gut barrier function, modulate the intestinal microbiota, decrease systemic inflammatory response and may advance the clinical outcomes in critically ill patients. This article is protected by copyright. All rights reserved.

A comparison of various intragastric balloons for the assessment of gastric motility

BACKGROUND

There is a clear need for a novel method to readily assess gastric motility in daily clinical practice.

METHODS

In a crossover design, 10 noncompliant balloons of different shape and volume (25-350 mL), attached to a classic feeding tube, were introduced in the stomach of eight healthy volunteers. In the same experiment, a High-Resolution Manometry (HRM) catheter was positioned throughout the stomach. Gastric motility was recorded during fasting (2 hours) and liquid nutrient administration (30 minutes). Motility was quantified using a peak detection algorithm. Symptoms were recorded throughout the experiment using visual analog scales (100 mm). Results are presented as mean ± SD.

KEY RESULTS

The % time during which motility-induced pressure increments could be detected with HRM but not by the balloon varied from 42 ± 24% in the smallest (25 mL) balloon to 1 ± 1% in the 330 mL balloon. On the other hand, bloating, discomfort and nausea scores were 0 ± 0, 0 ± 0 and 2 ± 5 mm, respectively, for the smallest balloon (25 mL) while these scores were 28 ± 38, 13 ± 30, and 38 ± 30 mm, respectively, for the largest balloon (350 mL). A phase III contraction pattern was consistently evoked in balloons with a volume >200 mL.

CONCLUSION

Gastric motility could be assessed more accurately with larger volume balloons, while epigastric symptoms were evoked with increasing balloon volume. The optimal balloon to measure gastric motility has a 5 cm diameter and is 11 cm long (210 mL). A nasogastric balloon catheter can now be developed that enables relatively easy monitoring of gastric motility in patients with epigastric symptoms.

Measuring gastric residual volumes in critically ill burn patients - A systematic review

PURPOSE

Measuring gastric residual volumes (GRV) is common in intensive care units (ICU) in patients receiving enteral nutrition (EN) and are a common source of feeding interruptions. Interruptions in EN yield adverse outcomes and are an area of improvement in burn care. The objectives of this study are to summarize the literature's ICU GRV practices and offer practical suggestions to GRV management in the burn patient.

METHODS

PubMed, SCOPUS, and OvidSP Medline were systematically reviewed using the keywords: burns; thermal injury; gastric residual volume; enteral feeding; tube feeding; enteral nutrition; gastric intolerance; ICU; critical illness. Reviews, case reports, and consensus and opinion papers were excluded.

RESULTS

26 articles were identified. Six burn-specific studies were identified. GRV practices vary widely and are a common cause of EN interruption. Elevated GRVs do not equate to gastrointestinal intolerance and do not always reflect aspiration risk.

CONCLUSIONS

We advocate a GRV threshold of 500mL should be used to optimize the benefits of EN in burn ICUs. A single incident of elevated GRVs should not mandate immediate EN rate reduction or cessation but should prompt a thoughtful examination of secondary causes of gastrointestinal intolerance. Randomized controlled trials are needed to define the ideal GRV threshold and re-evaluate its role in burn care.

Natural Bioactive Food Components for Improving Enteral Tube Feeding Tolerance in Adult Patient Populations

Tube feeding (TF) is the most common form of nutrition support. In recent years, TF administration has increased among patient populations within and outside hospital settings, in part due to greater insurance coverage, reduced use of parenteral nutrition, and improved formularies suitable for sole source nutrition. With increasing life expectancy and improved access to TFs, the number of adults dependent on enteral nutrition is expected to grow. However, enteral TF intolerance (ETFI) is the most common complication of TFs, typically presenting with at least 1 adverse gastrointestinal event, including nausea, diarrhea, and constipation. ETFI often leads to reductions in TF volume with associated energy and protein deficits. Potentially ensuing malnutrition is a major public health concern due its effects on increased risk of morbidity and mortality, infections, prolonged hospital length of stay, and higher healthcare costs. As such, there is a need for intervention strategies to prevent and reduce ETFI. Incorporating whole foods with bioactive properties is a promising strategy. Emerging research has elucidated bioactive properties of whole foods with specific benefits for the prevention and management of adverse gastrointestinal events commonly associated with TFs. However, lack of evidence-based recommendations and technological challenges have limited the use of such foods in commercial TF formulas. This review addresses research gaps by discussing 5 whole foods (rhubarb, banana, curcumin, peppermint oil, and ginger) with bioactive attributes identified through literature searches and clinical experience as having substantial scientific rationale to consider their application for ETFI in adult populations.

Increased Efficacy and Safety of Enteral Nutrition Support with a Protocol (ASNET) in Noncritical Patients: A Randomized Controlled Trial

BACKGROUND

Unintentional underfeeding is common in patients receiving enteral nutrition (EN), and is associated with increased risk of malnutrition complications. Protocols for EN in critically ill patients have been shown to enhance adequacy, resulting in better clinical outcomes; however, outside of intensive care unit (ICU) settings, the influence of a protocol for EN is unknown.

OBJECTIVE

To evaluate the efficacy and safety of implementing an EN protocol in a noncritical setting.

DESIGN

Randomized controlled clinical trial.

PARTICIPANTS AND SETTINGS

This trial was conducted from 2014 to 2016 in 90 adult hospitalized patients (non-ICU) receiving exclusively EN. Patients with carcinomatosis, ICU admission, or <72 hours of EN were excluded.

INTERVENTION

The intervention group received EN according to a protocol, whereas the control group was fed according to standard practice.

MAIN OUTCOME MEASURES

The proportion of patients receiving ≥80% of their caloric target at Day 4 after EN initiation.

STATISTICAL ANALYSES PERFORMED

Student t test or Wilcoxon rank-sum test were used for continuous variables and the difference between the groups in the time to receipt of the optimal amount of nutrition was analyzed using Kaplan-Meier curves.

RESULTS

Forty-five patients were randomized to each group. At Day 4 after EN initiation, 61% of patients in the intervention arm had achieved the primary end point compared with 23% in the control group (P=0.001). In malnourished patients, 63% achieved the primary end point in the intervention group compared with 16% in the control group (P=0.003). The cumulative deficit on Day 4 was lower in the intervention arm compared with the control arm: 2,507 kcal (interquartile range [IQR]=1,262 to 2,908 kcal) vs 3,844 kcal (IQR=2,620 to 4,808 kcal) (P<0.001) and 116 g (IQR=69 to 151 g) vs 191 g (IQR=147 to 244 g) protein (P<0.001), respectively. The rates of gastrointestinal complications were not significantly different between groups.

CONCLUSIONS

Implementation of an EN protocol outside the ICU significantly improved the delivery of calories and protein when compared with current standard practice without increasing gastrointestinal complications.

Pharmacological therapy of feed intolerance in the critically ills

Feed intolerance in the setting of critical illness is associated with higher morbidity and mortality, and thus requires promptly and effective treatment. Prokinetic agents are currently considered as the first-line therapy given issues relating to parenteral nutrition and post-pyloric placement. Currently, the agents of choice are erythromycin and metoclopramide, either alone or in combination, which are highly effective with relatively low incidence of cardiac, hemodynamic or neurological adverse effects. Diarrhea, however, can occur in up to 49% of patients who are treated with the dual prokinetic therapy, which is not associated with Clostridium difficile infection and settled soon after the cessation of the drugs. Hence, the use of prokinetic therapy over a long period or for prophylactic purpose must be avoided, and the indication for ongoing use of the drug(s) must be reviewed frequently. Second line therapy, such as total parenteral nutrition and post-pyloric feeding, must be considered once adverse effects relating the prokinetic therapy develop.

Current issues on safety of prokinetics in critically ill patients with feed intolerance

Feed intolerance in the setting of critical illness should be treated promptly given its adverse impact on morbidity and mortality. The technical difficulty of postpyloric feeding tube placement and the morbidities associated with parenteral nutrition prevent these approaches being considered as first-line nutrition. Prokinetic agents are currently the mainstay of therapy for feed intolerance in the critically ill. Current information is limited but suggests that erythromycin or metoclopramide (alone or in combination) are effective in the management of feed intolerance in the critically ill and not associated with significant cardiac, haemodynamic or neurological adverse effects. However, diarrhoea is a very common gastrointestinal side effect, and can occur in up to 49% of patients who receive both erythromycin and metoclopramide. Fortunately, the diarrhoea associated with prokinetic treatments has not been linked to Clostridium difficile infection and settles soon after the drugs are ceased. Therefore, prolonged or prophylactic use of prokinetics should be avoided. If diarrhoea occurs, the drugs should be stopped immediately. To minimize avoidable adverse effects the ongoing need for prokinetic drugs in these patient should be reviewed daily.

Impact of disease severity on gastric residual volume in critical patients

AIM: To investigate whether illness severity has an impact on gastric residual volume (GRV) in medical critically ill patients.

METHODS: Medical intensive care unit (ICU) patients requiring nasogastric feeding were enrolled. Sequential Organ Failure Assessment (SOFA) score was assessed immediately preceding the start of the study. Acute Physiology and Chronic Health Evaluation (APACHE) II scores were recorded on the first, fourth, seventh, and fourteenth day of the study period. GRV was measured every 4 h during enteral feeding. The relationship between mean daily GRV and SOFA scores and the correlation between mean daily GRV and mean APACHE II score of all patients were evaluated and compared.

RESULTS: Of the 61 patients, 43 patients were survivors and 18 patients were non-survivors. The mean daily GRV increased as SOFA scores increased (P < 0.001, analysis of variance). Mean APACHE II scores of all patients correlated with mean daily GRV (P = 0.011, Pearson correlation) during the study period. Patients with decreasing GRV in the first 2 d had better survival than patients without decreasing GRV (P = 0.017, log rank test).

CONCLUSION: GRV is higher in more severely ill medical ICU patients. Patients with decreasing GRV had lower ICU mortality than patients without decreasing GRV.

Impact of not measuring residual gastric volume in mechanically ventilated patients receiving early enteral feeding: a prospective before-after study

BACKGROUND

Monitoring of residual gastric volume (RGV) to prevent aspiration is standard practice in mechanically ventilated patients receiving early enteral nutrition (EN). No data are available to support a correlation between RGV and adverse event rates. We evaluated whether not measuring RGV affected EN delivery, vomiting, or risk of nosocomial pneumonia.

METHODS

Two hundred and five eligible patients with nasogastric feeding within 48 hours after intubation were included in a 7-day prospective before-after study. Continuous 24-hour nutrition was started at 25 mL/h then increased by 25 mL/h every 6 hours, to 85 mL/h. In both groups, intolerance was treated with erythromycin (250 mg IV/6 h) and a delivery rate decrease to the previously well-tolerated rate. RGV monitoring was used during the first study period (n = 102), but not during the subsequent intervention period (n = 103). Intolerance was defined as RGV >250 mL/6 h or vomiting in the standard-practice group and as vomiting in the intervention group.

RESULTS

Groups were similar for baseline characteristics. Median daily volume of enteral feeding was higher in the intervention group (1489; interquartile range [IQR], 1349-1647) than in the controls (1381; IQR, 1151-1591; P = .002). Intolerance occurred in 47 (46.1%) controls and 27 (26.2%) intervention patients (P = .004). The vomiting rate did not differ between controls and intervention group patients (24.5% vs 26.2%, respectively; P = .34), and neither was a difference found for ventilator-associated pneumonia (19.6% vs 18.4%; P = .86).

CONCLUSION

Early EN without RGV monitoring in mechanically ventilated patients improves the delivery of enteral feeding and may not increase vomiting or ventilator-associated pneumonia.

Gastrointestinal symptoms in intensive care patients

BACKGROUND

Gastrointestinal (GI) problems are not uniformly assessed in intensive care unit (ICU) patients and respective data in available literature are insufficient. We aimed to describe the prevalence, risk factors and importance of different GI symptoms.

METHODS

We prospectively studied all patients hospitalized to the General ICU of Tartu University Hospital in 2004-2007.

RESULTS

Of 1374 patients, 62 were excluded due to missing data. Seven hundred and seventy-five (59.1%) patients had at least one GI symptom at least during 1 day of their stay, while 475 (36.2%) suffered from more than one symptom. Absent or abnormal bowel sounds were documented in 542 patients (41.3%), vomiting/regurgitation in 501 (38.2%), high gastric aspirate volume in 298 (22.7%), diarrhoea in 184 (14.0%), bowel distension in 139 (10.6%) and GI bleeding in 97 (7.4%) patients during their ICU stay. Absent or abnormal bowel sounds and GI bleeding were associated with significantly higher mortality. The number of simultaneous GI symptoms was an independent risk factor for ICU mortality. The ICU length of stay and mortality of patients who had two or more GI symptoms simultaneously were significantly higher than in patients with a maximum of one GI symptom.

CONCLUSION

GI symptoms occur frequently in ICU patients. Absence of bowel sounds and GI bleeding are associated with impaired outcome. Prevalence of GI symptoms at the first day in ICU predicts the mortality of the patients.

New-onset constipation at acute stage after first stroke: incidence, risk factors, and impact on the stroke outcome

BACKGROUND AND PURPOSE

The prevalence of constipation after stroke varies from 30% to 60%. The incidence of new-onset constipation during the early stage of stroke remains uncertain. The present study was designed to investigate the prevalence of new-onset constipation, its risk factors, and its impact on stroke outcome in patients with their first stroke at acute stage.

METHODS

This is a prospective cohort study of 154 patients admitted with their first stroke. New-onset constipation during the first 4 weeks of stroke was recorded, using the Rome II criteria for constipation. Demographics, characteristics of the stroke, laboratory parameters, and use of medications were evaluated as risk factors for constipation. Death, recurrent stroke, and handicap at 12 weeks were regarded as poor outcome. The impact of constipation on poor outcome was also studied.

RESULTS

The cumulative incidence of new-onset constipation was 55.2% at 4 weeks poststroke. The occurrence of constipation was associated with dependence (P<0.01) and use of bedpan for defecation (P<0.05). Among patients with moderate stroke severity (NIHSS 4 to 11) at baseline, constipation at 4 weeks was associated with a poor outcome at 12 weeks.

CONCLUSIONS

New-onset constipation is a common complication of acute stroke. Its occurrence is associated with dependence and use of bedpan for defecation. Its development may predict a poor outcome at 12 weeks in patients with moderately severe stroke.

Prokinetic therapy for feed intolerance in critical illness: one drug or two?

OBJECTIVE

To compare the efficacy of combination therapy, with erythromycin and metoclopramide, to erythromycin alone in the treatment of feed intolerance in critically ill patients.

DESIGN

Randomized, controlled, double-blind trial.

SETTING

Mixed medical and surgical intensive care unit.

PATIENTS

Seventy-five mechanically ventilated, medical patients with feed intolerance (gastric residual volume > or =250 mL).

INTERVENTIONS

Patients received either combination therapy (n = 37; 200 mg of intravenous erythromycin twice daily + 10 mg of intravenous metoclopramide four times daily) or erythromycin alone (n = 38; 200 mg of intravenous erythromycin twice daily) in a prospective, randomized fashion. Gastric feeding was re-commenced and 6-hourly gastric aspirates performed. Patients were studied for 7 days. Successful feeding was defined as a gastric residual volume <250 mL with the feeding rate > or =40 mL/hr, over 7 days. Secondary outcomes included daily caloric intake, vomiting, postpyloric feeding, length of stay, and mortality.

MEASUREMENTS AND MAIN RESULTS

Demographic data; use of inotropes, opioids, or benzodiazepines; and pretreatment gastric residual volume were similar between the two groups. The gastric residual volume was significantly lower after 24 hrs of treatment with combination therapy, compared with erythromycin alone (136 +/- 23 mL vs. 293 +/- 45 mL, p = .04). Over the 7 days, patients treated with combination therapy had greater feeding success, received more daily calories, and had a lower requirement for postpyloric feeding, compared with erythromycin alone. Tachyphylaxis occurred in both groups but was less with combination therapy. Sedation, higher pretreatment gastric residual volume, and hypoalbuminemia were significantly associated with a poor response. There was no difference in the length of hospital stay or mortality rate between the groups. Watery diarrhea was more common with combination therapy (20 of 37 vs. 10 of 38, p = .01) but was not associated with enteric infections, including Clostridium difficile.

CONCLUSIONS

In critically ill patients with feed intolerance, combination therapy with erythromycin and metoclopramide is more effective than erythromycin alone in improving the delivery of nasogastric nutrition and should be considered as the first-line treatment.

Standardized concept for the treatment of gastrointestinal dysmotility in critically ill patients--current status and future options

Inhibition of gastrointestinal motility is a major problem in critically ill patients. Motor stasis gives rise to subsequent complications including intolerance to enteral feeding, enhanced permeability of the atrophic intestinal mucosa and conditions as severe as systemic inflammatory response syndrome, sepsis and multiple organ failure. Although the diagnosis of motility disturbances in critically ill patients is difficult, the type and site of the disturbance are important to consider in the analysis of the condition and in the choice of therapeutic approach. The pharmacological treatment of impaired gastrointestinal motility is difficult to handle for the clinician, because the underlying mechanisms are complex and not fully understood and the availability of pharmacological treatment options is limited. In addition, there is a lack of controlled studies on which to build an evidence-based treatment concept for critically ill patients. Notwithstanding this situation, there has been remarkable progress in the understanding of the integrated regulation of gastrointestinal motility in health and disease. These advances, which largely relate to the organization of the enteric nervous system and its signaling mechanisms, enable the intensivist to develop a standardized concept for the use of prokinetic agents in the treatment of impaired gastrointestinal motility in critically ill patients.

Risk of Clostridium difficile diarrhoea in critically ill patients treated with erythromycin-based prokinetic therapy for feed intolerance

OBJECTIVE

To determine the incidence of Clostridium difficile (CD) diarrhoea in feed-intolerant, critically ill patients who received erythromycin-based prokinetic therapy.

DESIGN AND SETTING

Prospective observational study in a mixed intensive care unit.

METHODS

The development of diarrhoea (> 3 loose, liquid stool per day with an estimated total volume > or = 250ml/day) was assessed in 180 consecutive critically ill patients who received prokinetic therapy (erythromycin only, n = 53; metoclopramide, n 37; combination erythromycin/metoclopramide, n = 90) for feed intolerance. Stool microscopy, culture and CD toxin assay were performed in all patients who developed diarrhoea during and after prokinetic therapy. Diarrhoea was deemed to be related to CD infection if CD toxin was detected.

RESULTS

Demographics, antibiotic use and admission diagnosis were similar amongst the three patients groups. Diarrhoea developed in 72 (40%) patients, 9.9 +/- 0.8 days after commencement of therapy, none of whom was positive for CD toxin or bacterial infection. Parasitic infections were found in four aboriginal men from an area endemic for these infections. Diarrhoea was most prevalent in patients who received combination therapy (49%) and was more common than in those who received erythromycin alone (30%) and metoclopramide alone (32%). Diarrhoea was short-lasting with a mean duration of 3.6 +/- 1.2 days.

CONCLUSIONS

In critical illness, diarrhoea following the administration of erythromycin at prokinetic doses is not associated with CD but may be related to pro-motility effects of the agent. Prokinetic therapy should be stopped at the onset of diarrhoea and prophylactic use should be strictly avoided.

Risk of Clostridium difficile diarrhoea in critically ill patients treated with erythromycin-based prokinetic therapy for feed intolerance

OBJECTIVE

To determine the incidence of Clostridium difficile (CD) diarrhoea in feed-intolerant, critically ill patients who received erythromycin-based prokinetic therapy.

DESIGN AND SETTING

Prospective observational study in a mixed intensive care unit.

METHODS

The development of diarrhoea (> 3 loose, liquid stool per day with an estimated total volume > or = 250ml/day) was assessed in 180 consecutive critically ill patients who received prokinetic therapy (erythromycin only, n = 53; metoclopramide, n 37; combination erythromycin/metoclopramide, n = 90) for feed intolerance. Stool microscopy, culture and CD toxin assay were performed in all patients who developed diarrhoea during and after prokinetic therapy. Diarrhoea was deemed to be related to CD infection if CD toxin was detected.

RESULTS

Demographics, antibiotic use and admission diagnosis were similar amongst the three patients groups. Diarrhoea developed in 72 (40%) patients, 9.9 +/- 0.8 days after commencement of therapy, none of whom was positive for CD toxin or bacterial infection. Parasitic infections were found in four aboriginal men from an area endemic for these infections. Diarrhoea was most prevalent in patients who received combination therapy (49%) and was more common than in those who received erythromycin alone (30%) and metoclopramide alone (32%). Diarrhoea was short-lasting with a mean duration of 3.6 +/- 1.2 days.

CONCLUSIONS

In critical illness, diarrhoea following the administration of erythromycin at prokinetic doses is not associated with CD but may be related to pro-motility effects of the agent. Prokinetic therapy should be stopped at the onset of diarrhoea and prophylactic use should be strictly avoided.

Enteral nutrition in critically ill children: are prescription and delivery according to their energy requirements?

BACKGROUND

The purpose of this study was to compare the differences between prescribed and delivered energy among critically ill children and to identify the factors that impede the optimal delivery of enteral nutrition in the first 5 days of nutrition support.

METHODS

In a prospective cohort study, we evaluated 55 critically ill children aged 8.2 +/- 11.4 months (0-162.3 months), who were fed for > or =2 days through a gastric or postpyloric tube. The patients were followed from admission until day 10 of enteral nutrition. Prescribed and delivered energy were recorded daily and compared with each other and with the estimated basal metabolic rate (BMR). The Paediatric Index of Mortality 2 (PIM 2) was used to estimate illness severity.

RESULTS

The ratio of delivered:required energy was <90% in 55.7% of the enteral nutrition days. Low prescription was the main reason for not achieving the energy goal in the first 5 days of enteral nutrition. Discrepancies between prescribed and delivered: energy were attributable to interruptions in feeding caused by clinical instability, airway management, radiologic and surgical procedures, and accidental feeding tube removal. The other factors associated with the delivery of less than required energy were PIM 2 > or =15%, gastrointestinal complications, dialysis, and use of alpha-adrenergic vasoactive drugs. The latter was the only variable in multivariate analysis that was associated with not ultimately achieving energy goal.

CONCLUSIONS

The prescription and delivery of energy were not adequate in >50% of enteral nutrition days. The gap between the effective administration and energy requirements can be explained by both underprescription and underdelivery. Administration of vasoactive drugs was the only variable independently associated with a low energy supply.

Erythromycin is more effective than metoclopramide in the treatment of feed intolerance in critical illness

OBJECTIVE

This study aimed to a) compare the efficacy of metoclopramide and erythromycin in the treatment of feed intolerance in critical illness; and b) determine the effectiveness of "rescue" combination therapy in patients who fail monotherapy.

DESIGN

Randomized controlled trial.

SETTING

Level III mixed medical and surgical intensive care unit.

PATIENTS

Ninety mechanically ventilated, medical patients with feed-intolerance (gastric residual volume>or=250 mL).

INTERVENTIONS

Patients received either metoclopramide 10 mg intravenously four times daily (n=45) or erythromycin 200 mg intravenously twice a day (n=45) in a double-blind, randomized fashion. After the first dose, nasogastric feeding was commenced and 6-hourly nasogastric aspirates were performed. If a gastric residual volume>or=250 mL recurred on treatment, open-label, combination therapy was given. Patients were studied for 7 days. Successful feeding was defined as 6-hourly gastric residual volume<250 mL with a feeding rate>or=40 mL/hr.

MEASUREMENTS AND MAIN RESULTS

Demographic data, blood glucose levels, and use of inotropes, opioids, and benzodiazepines were similar between the two groups. After 24 hrs of treatment, both monotherapies reduced the mean gastric residual volume (metoclopramide, 830+/-32 mL to 435+/-30 mL, p<.0001; erythromycin, 798+/-33 mL to 201+/-19 mL, p<.0001) and improved the proportion of patients with successful feeding (metoclopramide=62% and erythromycin=87%). Treatment with erythromycin was more effective than metoclopramide, but the effectiveness of both treatments declined rapidly over time. In patients who failed monotherapy, rescue combination therapy was highly effective (day 1=92%) and maintained its effectiveness for the study duration (day 6=67%). High pretreatment gastric residual volume was associated with poor response to prokinetic therapy.

CONCLUSIONS

In critical illness, erythromycin is more effective than metoclopramide in treating feed intolerance, but the rapid decline in effectiveness renders both treatments suboptimal. Rescue combination therapy is highly effective, and further study is required to examine its role as the first-line therapy.

Early postoperative gastric enteral nutrition improve gastric emptying after cardiac surgery

Postoperative intragastric enteral feeding in cardiac surgery patients is frequently complicated by delayed gastric emptying. The aim of the study was to evaluate how early postoperative gastric enteral nutrition affects the gastric emptying in coronary artery by-pass graft (CABG) surgery patients.

In the prospective, randomized study 40 patients treated at intensive care unit after CABG surgery were studied. Patients were divided in two groups: enteral feeding group E (20 patients: age 59±8 yr.; male 70%) and control group C (20 patients: age 58±10 yr.; male 80%), respectively. Paracetamol absorption test was used to evaluate gastric emptying. In the group E postoperative gastric supply of enteral formula begun 18 hours after surgery and after 6 hours the supply was stopped and paracetamol solution was administrated by nasogastric tube. The patients in group C for.rst 24 hours received only crystalloid solutions intravenously and paracetamol solution by nasogastric tube. Blood samples were obtained at 0 (t0), 15 (t+15), 30 (t+30), 60 (t+60) and 120 (t+120) min after administration of paracetamol.

The values of plasma paracetamol concentration (PPC) at 15 and 120 min were significantly higher in group E vs. group C: (t+15) 3.3±2.5 vs. 1.7±1.9 and (t+120) 5.2−2.8 vs. 3.3±1.6 (p <0.05). The PPC values at 30 and 60 min were higher, but not signi.cantly, in group E vs. group C: (t+30) 3.7±2.0 vs. 2.9±2.7 and (t+60) 5.1±3.2 vs. 3.9±3.5 (p = NS). The area under the PPC curve was 429 ± 309 in the E group vs. 293 ± 204 in the group C (p < 0.05).

In conclusion an early postoperative gastric administration of nutritients after CABG surgery stimulates the gastric emptying.

Enteral feeding in the critically ill: are nursing practices contributing to hypocaloric feeding?

INTRODUCTION

Enteral feeding is the preferred method of nutritional support for the critically ill; however, a significant number of these patients are under-fed. It is possible that common nursing practices associated with the delivery of enteral feeding may contribute to under-feeding although there is little data available describing nursing practice in this area.

METHOD

A descriptive survey-based design was used to explore the enteral feeding practices of 376 critical care nurses (response rate 50.5%). Participants completed a 57-item survey that focused on general enteral feeding practice and the management of feeding intolerance and complications.

RESULTS

The enteral feeding practice of critical care nurses varied widely and included some practices that could contribute to under-feeding in the critically ill. Practices associated with the measurement of gastric residual volumes (GRV) were identified as the most significant potential contributor to under-feeding. GRV measurements were commonly used to assess feeding tolerance (n = 338; 89.9%) and identified as a reason to delay feeding (n = 246; 65.4%). Delayed gastric emptying was frequently managed by prokinetic agents (n = 237; 63%) and decreasing the rate of feeding (n = 247; 65.7%) while nursing measures, such as changing patient position (n = 81; 21.5%) or checking tube placement (n = 94; 25%) were less frequently reported.

CONCLUSION

The findings of this survey support the contention that nursing practices associated with the delivery of enteral feeds may contribute to under-feeding in the critically ill patient population.

Preventing prolonged post-operative ileus in gastric cancer patients undergoing gastrectomy and intra-peritoneal chemotherapy

AIM: To assess the efficacy of metoclopramide (Met) for prevention of prolonged post-operative ileus in advanced gastric cancer patients undergoing D2 gastrectomy and intra-peritoneal chemotherapy (IPC).

METHODS: Thirty-two advanced gastric cancer patients undergoing D2 gastrectomy and IPC were allocated to two groups. Sixteen patients received Met immediately after operation (group A), and 16 did not (group B). Another 16 patients who underwent D2 gastrectomy without IPC were enrolled as the control group (group C). All patients had received epidural pain control. The primary endpoints were time to first post-operative flatus and time until oral feeding with a soft diet without discomfort. Secondary endpoints were early complications during hospitalization.

RESULTS: Gender, the type of resection, operating time, blood loss, tumor status and amount of narcotics were comparable in the three groups. However, the group C patients were older than those in groups A and B (67.5±17.7 vs 56.8±13.2, 57.5±11.7 years, P = 0.048). First bowel flatus occurred after 4.35±0.93 d in group A, 4.94±1.37 d in group B, and 4.71±1.22 d in group C (P>0.05). Oral feeding of a soft diet was tolerated 7.21±1.92 d after operation in group A, 10.15±2.17 d in group B, and 7.53±1.35 d in group C (groups A and C vs group B, P<0.05). There was no significant difference in respect to the first flatus among the three groups. However, the time of tolerating oral intake with soft food in groups A and C patients was significantly shorter than that in group B patients. Levels of C-reactive protein (CRP) were significantly lower in group C and there was a more prominent and prolonged response in CRP level in patients undergoing IPC. The incidence of post-operative complications was similar in the three groups except for prolonged post-operative ileus. There was no increased risk of anastomotic leakage in patients receiving Met.

CONCLUSION: The results suggest that a combination of intravenous Met and epidural pain control may be required to achieve a considerable decrease in time to resumption of oral soft diet in advanced gastric cancer patients who underwent gastrectomy and IPC. Furthermore, the administration of Met did not increase anastomotic leakage. Met has a role in the prevention of prolonged post-operative ileus.

Is early enteral nutrition a risk factor for gastric intolerance and pneumonia?

BACKGROUND

Early enteral nutrition (EN) after injury reduces septic complications, but upper digestive intolerance (UDI) occurring immediately post-trauma is a risk factor for pneumonia. Our study aimed to determine whether early intragastric feeding may lead to gastric intolerance and subsequent pneumonia in ventilated multiply injured patients.

METHODS

This prospective study involved two groups of patients randomized either to immediate intragastric EN, or to delayed intragastric EN started later than 24 h after admission. UDI was diagnosed when gastric residual volume, measured with a 50-ml syringe after stopping the feeding for 2 h, exceeded 200 ml at least at two consecutive measurements, and/or when vomiting occurred.

RESULTS

Out of 52 patients, 27 were included in the early EN group, and 25 in the delayed-EN group. On day 4, the early EN group received a greater amount of feeding because of intolerance problems occurring in the delayed-EN group (1175 +/- 485 ml vs. 803 +/- 545 ml). Twenty-five subjects--33% of the early EN patients and 64% of the delayed-EN patients--met the criteria for pneumonia (P = 0.050). On average, patients with pneumonia were older, more severely injured, and therefore required more ventilator days and a longer stay in the intensive care unit than patients without pneumonia.

CONCLUSIONS

If properly administered, early enteral nutrition can decrease the incidence of upper intestinal intolerance and nosocomial pneumonia in patients with multiple injuries.

Gastric residual volumes in critically ill paediatric patients: a comparison of feeding regimens

This study examined the effect of gastric feeding regimens, either continuous or intermittent, on fourth hourly gastric residual volumes (GRV) in a group of critically ill paediatric patients where delayed gastric emptying is defined as a GRV greater than 5ml/kg. A randomised controlled trial was conducted in a tertiary paediatric intensive care unit (PICU), with 45 participants being randomly assigned to either the continuous (n=22) or intermittent (n=23) gastric feeding groups. Participants remained in the assigned group for the duration of the study and, fourth hourly, GRV were assessed to monitor the incidence of delayed gastric emptying. Both groups were similar in age, weight, gender, diagnosis, paediatric index mortality (PIM) score, and usage of pharmacological agents known to affect the gastrointestinal tract. No differences emerged in study duration or the volume of administered enteral formula (ml/kg/day). The intermittent feeding group commenced enteral feeding earlier in the PICU admission (13.0 hours versus 18.5 hrs, p=0.05). Repeated measures analysis revealed no overall difference in median GRV/kg values between treatment groups over the 72 hour study period. Additionally, the incidence of fourth hourly GRV, greater than 5ml/kg, was not different between the continuous and intermittent feeding groups. The provision of enteral nutrition via the gastric route is a common treatment in the PICU, and GRV are frequently used as a measure of gastric tolerance. The result of this analysis provides some support for the theoretical definition of delayed gastric emptying being >5ml/kg. However, further work is required to confirm this finding and to determine its relevance when providing enteral nutrition to the critically ill paediatric patient.

Effect of gastrointestinal motility and feeding tube site on aspiration risk in critically ill patients: a review

OBJECTIVE

The purpose of this literature review is to examine the effect of the interaction between gastrointestinal motility and feeding site on the aspiration risk in critically ill, tube-fed patients.

METHODS AND RESULTS

A single answer to the question of the preferred feeding site is not likely to be found because the degree of aspiration risk varies significantly according to individual variations in gastrointestinal motility and multiple pre-existing and treatment-related risk factors. However, regardless of the feeding site, it is ultimately regurgitated gastric contents that are aspirated into the lungs. For this reason, the clinical assessment of greatest interest is the evaluation of gastric emptying, usually monitored clinically by measuring gastric residual volumes.

CONCLUSION

Current recommendations for monitoring residual volumes and preventing aspiration are provided.

The pragmatics of feeding the pediatric patient with acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) represents the ultimate pulmonary response to a wide range of injuries, from septicemia to trauma. Optimal nutrition is vital to enhancing oxygen delivery, supporting adequate cardiac contractility and respiratory musculature, eliminating fluid and electrolyte imbalances, and supporting the proinflammatory response. Research is providing a better understanding of nutrients that specifically address the complex physiologic changes in ARDS. This article highlights the pathophysiology of ARDS as it relates to nutrition, relevant nutritional assessment, and important enteral and parenteral considerations for the pediatric patient who has ARDS.

Enteral Administration of Naloxone for Treatment of Opioid-Associated Intragastric Feeding Intolerance

Intragastric enteral feeding intolerance, common in the intensive care setting, is attributed to many causes. Opioid antagonists such as naloxone may have a role in reversing the intolerance when it is associated with intravenous opioid infusions. A 38-year-old woman hospitalized for acute respiratory distress syndrome was supported with low tidal volume mechanical ventilation. She required lorazepam and morphine administered by continuous intravenous infusion to achieve ventilator synchrony and pain control. While receiving these therapies, the patient developed persistent intolerance to intragastric feeding. Intravenous metoclopramide and laxatives did not decrease gastric volume residuals, and insertion of a jejunal tube was deemed unsafe due to worsening of her respiratory status. Total parenteral nutrition was begun to meet her caloric needs, but she experienced repeated catheter-related bloodstream infections. Naloxone 2 mg by gastric tube every 8 hours for 8 days was started; the dosage then was increased to 4 mg every 8 hours. Tube feeding was restarted, which provided the patient with more than 90% of her daily caloric needs and allowed for discontinuation of parenteral nutrition. With this dosage of naloxone, tolerance to intragastric feeding was maintained until the patient's death due to refractory respiratory failure. Enterally administered naloxone is an effective, noninvasive means of reversing intolerance to intragastric feeding associated with opioids.

Gastric emptying in mechanically ventilated critically ill patients: effect of neuromuscular blocking agent

OBJECTIVE

To assess gastrointestinal function in critically ill patients receiving muscle relaxant and to test clinical tolerance to enteral nutrition.

DESIGN AND SETTING

Prospective study in an intensive care unit.

PATIENTS

20 critically ill patients requiring sedation with muscle relaxant to obtain adequate mechanical ventilation.

MEASUREMENTS AND RESULTS

Patients were randomly selected to receive infusions of opioid sedation during the first session (session 1) and the same sedation with muscle relaxation (cisatracurium) during the second session (session 2). Gastric emptying was assessed by the paracetamol absorption technique. Following the paracetamol absorption 200 ml enteral feed was given, and the residual gastric volume was measured 1 and 2 h after feeding. The maximum plasma concentration (Cmax) was 14 mg/l (range 5-26) when patients received sedation, and 12 mg/l (range 5-30) when they received muscle relaxant. The target time for reaching the maximum plasma concentration (Tmax) was 30 min (range 20-60) and 35 min (range 20-60), respectively, in sessions 1 and 2. There was no significant difference between the two session as regards Tmax, Cmax, or AUC(0-120). The residual volumes were 110+/-65 ml (H1) and 95+/-76 ml (H2) during session 1 and 125+/-85 ml (H1) and 105+/-90 ml (H2) during session 2.

CONCLUSIONS

Enteral feeding is one of the most effective methods of supporting nutritional needs in the critically ill patient. We conclude that in critically ill patients requiring sedation gastric emptying is not improved by neuromuscular blocking agent.

Future considerations in aspiration pneumonia in the critically ill patient: what is not known, areas for future research, and experimental methods

The medical literature supports the use of enteral feeding to provide nutrition and improve patient outcomes. A major complication of enteral feeding is aspiration and associated morbidity and mortality. Many knowledge gaps exist that inhibit our ability to define and diagnose aspiration, identify patients at risk, and develop prevention techniques. Several areas of inquiry should be explored to help us define and prevent the disorder--for instance, standardized criteria should be developed for diagnosing aspiration pneumonia and for differentiating it from other types of pneumonia, and accurate tests should be devised for detecting it. Research also is needed to evaluate the influence of (1) various enteral feeding sites on aspiration risk, (2) the effects of risk reduction techniques such as selective decontamination and use of promotility agents, and (3) potential benefits of immunonutrition. Current parameters used in decisions about when to initiate enteral feeding in critically ill patients are defined.

Gastrointestinal promotility drugs in the critical care setting: a systematic review of the evidence

CONTEXT

Gastrointestinal promotility agents may improve tolerance to enteral nutrition, reduce gastroesophageal reflux and pulmonary aspiration, and therefore have the potential to improve outcomes of critically ill patients.

OBJECTIVE

To systematically review and critically appraise studies of promotility agents in the critical care setting.

DATA SOURCES

Computerized bibliographic search of published research (1980-2001), citation review of relevant articles, and contact with primary investigators.

STUDY SELECTION

Randomized trials of critically ill adult patients that evaluated the effect of promotility agents on measures of gastrointestinal motility were included.

DATA EXTRACTION

Relevant methods and outcome data were abstracted in duplicate by independent investigators.

DATA SYNTHESIS

We reviewed 60 citations; 18 articles met the inclusion criteria (six studies of feeding tube placement, 11 studies evaluating gastrointestinal function, and one study of clinical outcomes). The heterogeneity of study methods and outcomes measured precluded a quantitative synthesis of the data. Although there are conflicting studies, the larger and more methodologically robust studies suggest that metoclopramide has no effect on feeding tube placement. Erythromycin has been shown to increase success rates with small-bowel tube placement in two studies. Eight of ten studies evaluating the effect of cisapride, metoclopramide, or erythromycin on measures of gastrointestinal transit demonstrated positive effects; the two studies that did not were relatively small (n = 27 and 10) and likely had inadequate power to detect a difference in treatment effect. No study demonstrated a positive effect on clinical outcomes.

CONCLUSIONS

As a class of drugs, promotility agents appear to have a beneficial effect on gastrointestinal motility in critically ill patients. A one-time dose of erythromycin may facilitate small-bowel feeding tube insertion. Administration of metoclopramide appears to increase physiologic indexes of gastrointestinal transit and feeding tolerance. Concerns about safety and lack of effect on clinically important outcomes preclude strong treatment recommendations.

Comparison of cisapride and metoclopramide for facilitating gastric emptying and improving tolerance to intragastric enteral nutrition in critically III, mechanically ventilated adults

BACKGROUND

Placebo-controlled studies have indicated that both cisapride and metoclopramide promote gastric motility in critically ill patients.

OBJECTIVE

This study was conducted to compare cisapride and metoclopramide for facilitating gastric emptying and improving tolerance to intragastric enteral nutrition (EN) and to evaluate the relationship between aspirated gastric residual volume and gastric emptying function in this patient population.

METHODS

In this double-blind study, critically ill, mechanically ventilated patients with an aspirated gastric residual volume > or = 150 mL while receiving intragastric EN were randomized to receive enteral cisapride 10 mg or metoclopramide 10 mg every 6 hours for a total of 7 doses. The acetaminophen-absorption method was used to assess gastric emptying at baseline and 30 minutes after the seventh dose by determining the area under the plasma concentration-time curve at 240 minutes (AUC240), maximum concentration (Cmax), and time to Cmax (Tmax). Gastric residual volume was measured every 6 hours before dosing.

RESULTS

Fourteen patients were included in the study, 7 in each group. Patient characteristics were similar in the 2 groups. Compared with baseline, metoclopramide significantly accelerated Tmax (39.00 +/- 15.56 min with metoclopramide vs 103.71 +/- 47.35 min at baseline; P = 0.018) and increased Cmax (12.94 +/- 6.68 mg/L vs 6.97 +/- 4.78 mg/L; P = 0.018) and AUC240 (1,421.43 +/- 780.31 mg/L x min vs 839.00 +/- 545.58 mg/L x min; P = 0.043). Cisapride increased Cmax from baseline (12.27 +/- 8.95 mg/L vs 4.53 +/- 2.37 mg/L, respectively), but the difference was not statistically significant. Gastric residual volume was significantly reduced from baseline after 3 doses of metoclopramide (from 268.7 +/- 112.3 mL to 57.0 +/- 23.1 mL; P < 0.05) and was significantly lower after the seventh dose of metoclopramide than after the seventh dose of cisapride (5.3 +/- 8.2 mL vs 41.4 +/- 39.7 mL, respectively; P = 0.05). Cmax at baseline and residual volume at study entry were inversely correlated (r = -0.50; P = 0.049).

CONCLUSIONS

Both cisapride and metoclopramide enhanced gastric motility and improved tolerance to intragastric EN. Metoclopramide reduced gastric residual volume to a significantly greater extent than did cisapride. Only Cmax at baseline was inversely associated with residual volume.