Common Pathophysiological Mechanisms and Treatment of Diabetic Gastroparesis

Diabetic gastroparesis (DGP) is a common complication of diabetes mellitus, marked by gastrointestinal motility disorder, a delayed gastric emptying present in the absence of mechanical obstruction. Clinical manifestations include postprandial fullness and epigastric discomfort, bloating, nausea, and vomiting. DGP may significantly affect the quality of life and productivity of patients. Research on the relationship between gastrointestinal dynamics and DGP has received much attention because of the increasing prevalence of DGP. Gastrointestinal motility disorders are closely related to a variety of factors including the absence and destruction of interstitial cells of Cajal, abnormalities in the neuro-endocrine system and hormone levels. Therefore, this study will review recent literature on the mechanisms of DGP and gastrointestinal motility disorders as well as the development of prokinetic treatment of gastrointestinal motility disorders in order to give future research directions and identify treatment strategies for DGP.

Use of prokinetic agents in hospitalised adult patients: A scoping review

BACKGROUND

Gastrointestinal motility is important for adequate uptake of fluids and nutrition but is often impaired in hospitalised patients. Prokinetic agents enhance gastrointestinal motility and are prescribed for many hospitalised patients. In this scoping review, we aimed to systematically describe the body of evidence on the use of prokinetic agents in hospitalised patients. We hypothesised, that the body of evidence would be limited and derive from heterogeneous populations.

METHODS

We conducted this scoping review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews statement. We searched Medline, Embase, Epistemonikos and the Cochrane Library for studies assessing the use of prokinetic agents on any indication and outcome in adult hospitalised patients. We used a modified version of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) to assess the certainty of evidence.

RESULTS

We included 102 studies with a total of 8830 patients. Eighty-six studies were clinical trials (84%), and 52 (60%) of these were conducted in the intensive care unit, with feeding intolerance as the main indication. In the non-intensive care setting the indications were wider; most studies assessed use of prokinetic agents before gastroscopy to improve visualisation. The most studied prokinetic agent was metoclopramide (49% of studies) followed by erythromycin (31%). In total 147 outcomes were assessed with only 67% of the included studies assessing patient-centred outcomes, and with gastric emptying as the most frequently reported outcome. Overall, the data provided no firm evidence on the balance between the desirable and undesirable effects of prokinetic agents.

CONCLUSIONS

In this scoping review, we found that the studies addressing prokinetic agents in hospitalised adults had considerable variations in indications, drugs and outcomes assessed, and that the certainty of evidence was judged to be low to very low.

The diagnostic accuracy of ultrasonography over manual aspiration for gastric reserve volume estimation in critically ill patients

BACKGROUND

Although gastric reserve volume (GRV) is a surrogate marker of gastrointestinal dysfunction and feeding intolerance, there is ambiguity in its estimation due to problems associated with its measurement. Introduction of point-of-care ultrasound as a tool for anesthetists kindled interest in its use for GRV estimation.

METHODS

In this prospective observational study, we recruited 57 critically ill patients and analyzed 586 samples of GRV obtained by both ultrasonography (USG) and manual aspiration.

RESULTS

The analysis showed that USG-guided GRV was significantly correlated (r=0.788, P<0.001) and in positive agreement with manual aspiration based on Bland-Altman plot, with a mean difference of 8.50±14.84 (95% confidence interval, 7.389-9.798). The upper and lower limits of agreement were 37.7 and -20.5, respectively, within the ±1.96 standard deviation (P<0.001). The respective sensitivity and positive predictive value, specificity and negative predictive value, and area under the curve of USG for feeding intolerance were 66.67%, 98.15%, and 0.82%, with 96.49% diagnostic accuracy.

CONCLUSIONS

Ultrasonographic estimation of GRV was positively, significantly correlated and in agreement with the manual aspiration method and estimated feeding intolerance earlier. Routine use of gastric USG could avoid clinical situations where feeding status is unclear and there is high risk of aspiration and could become a standard practice of critical care.

Erythromycin prior to endoscopy for acute upper gastrointestinal haemorrhage

BACKGROUND

Upper endoscopy is the definitive treatment for upper gastrointestinal haemorrhage (UGIH). However, up to 13% of people who undergo upper endoscopy will have incomplete visualisation of the gastric mucosa at presentation. Erythromycin acts as a motilin receptor agonist in the upper gastrointestinal (GI) tract and increases gastric emptying, which may lead to better quality of visualisation and improved treatment effectiveness. However, there is uncertainty about the benefits and harms of erythromycin in UGIH.

OBJECTIVES

To evaluate the benefits and harms of erythromycin before endoscopy in adults with acute upper gastrointestinal haemorrhage, compared with any other treatment or no treatment/placebo.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 15 October 2021.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that investigated erythromycin before endoscopy compared to any other treatment or no treatment/placebo before endoscopy in adults with acute UGIH.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were 1. UGIH-related mortality and 2. serious adverse events. Our secondary outcomes were 1. all-cause mortality, 2. visualisation of gastric mucosa, 3. non-serious adverse events, 4. rebleeding, 5. blood transfusion, and 5. rescue invasive intervention. We used GRADE criteria to assess the certainty of the evidence for each outcome.  MAIN RESULTS: We included 11 RCTs with 878 participants. The mean age ranged from 53.13 years to 64.5 years, and most participants were men (72.3%). One RCT included only non-variceal haemorrhage, one included only variceal haemorrhage, and eight included both aetiologies. We defined short-term outcomes as those occurring within one week of initial endoscopy. Erythromycin versus placebo Three RCTs (255 participants) compared erythromycin with placebo. There were no UGIH-related deaths. The evidence is very uncertain about the short-term effects of erythromycin compared with placebo on serious adverse events (risk difference (RD) -0.01, 95% confidence interval (CI) -0.04 to 0.02; 3 studies, 255 participants; very low certainty), all-cause mortality (RD 0.00, 95% CI -0.03 to 0.03; 3 studies, 255 participants; very low certainty), non-serious adverse events (RD 0.01, 95% CI -0.03 to 0.05; 3 studies, 255 participants; very low certainty), and rebleeding (risk ratio (RR) 0.63, 95% CI 0.13 to 2.90; 2 studies, 195 participants; very low certainty). Erythromycin may improve gastric mucosa visualisation (mean difference (MD) 3.63 points on 16-point ordinal scale, 95% CI 2.20 to 5.05; higher MD means better visualisation; 2 studies, 195 participants; low certainty). Erythromycin may also result in a slight reduction in blood transfusion (MD -0.44 standard units of blood, 95% CI -0.86 to -0.01; 3 studies, 255 participants; low certainty). Erythromycin plus nasogastric tube lavage versus no intervention/placebo plus nasogastric tube lavage Six RCTs (408 participants) compared erythromycin plus nasogastric tube lavage with no intervention/placebo plus nasogastric tube lavage. There were no UGIH-related deaths and no serious adverse events. The evidence is very uncertain about the short-term effects of erythromycin plus nasogastric tube lavage compared with no intervention/placebo plus nasogastric tube lavage on all-cause mortality (RD -0.02, 95% CI -0.08 to 0.03; 3 studies, 238 participants; very low certainty), visualisation of the gastric mucosa (standardised mean difference (SMD) 0.48 points on 10-point ordinal scale, 95% CI 0.10 to 0.85; higher SMD means better visualisation; 3 studies, 170 participants; very low certainty), non-serious adverse events (RD 0.00, 95% CI -0.05 to 0.05; 6 studies, 408 participants; very low certainty), rebleeding (RR 1.13, 95% CI 0.63 to 2.02; 1 study, 169 participants; very low certainty), and blood transfusion (MD -1.85 standard units of blood, 95% CI -4.34 to 0.64; 3 studies, 180 participants; very low certainty). Erythromycin versus nasogastric tube lavage Four RCTs (287 participants) compared erythromycin with nasogastric tube lavage. There were no UGIH-related deaths and no serious adverse events. The evidence is very uncertain about the short-term effects of erythromycin compared with nasogastric tube lavage on all-cause mortality (RD 0.02, 95% CI -0.05 to 0.08; 3 studies, 213 participants; very low certainty), visualisation of the gastric mucosa (RR 1.19, 95% CI 0.79 to 1.79; 2 studies, 198 participants; very low certainty), non-serious adverse events (RD -0.10, 95% CI -0.34 to 0.13; 3 studies, 213 participants; very low certainty), rebleeding (RR 0.77, 95% CI 0.40 to 1.49; 1 study, 169 participants; very low certainty), and blood transfusion (median 2 standard units of blood, interquartile range 0 to 4 in both groups; 1 study, 169 participants; very low certainty). Erythromycin plus nasogastric tube lavage versus metoclopramide plus nasogastric tube lavage One RCT (30 participants) compared erythromycin plus nasogastric tube lavage with metoclopramide plus nasogastric tube lavage. The evidence is very uncertain about the effects of erythromycin plus nasogastric tube lavage on all the reported outcomes (serious adverse events, visualisation of gastric mucosa, non-serious adverse events, and blood transfusion).

AUTHORS' CONCLUSIONS

We are unsure if erythromycin before endoscopy in people with UGIH has any clinical benefits or harms. However, erythromycin compared with placebo may improve gastric mucosa visualisation and result in a slight reduction in blood transfusion.

Major Publications in the Critical Care Pharmacotherapy Literature: 2021

To summarize the most impactful articles relevant to the pharmacotherapy of critically ill adult patients published in 2021.

DATA SOURCE

PubMed/MEDLINE.

STUDY SELECTION

Randomized controlled trials, prospective studies, or systematic review/meta-analyses of adult critical care patients assessing a pharmacotherapeutic intervention and reporting clinical endpoints published between January 1, 2021, and December 31, 2021.

DATA EXTRACTION

Candidate articles were organized by clinical domain based on the emerging themes from all studies. A modified Delphi process was applied to obtain consensus on the most impactful publication within each clinical domain based on overall contribution to scientific knowledge and novelty to the literature.

DATA SYNTHESIS

The search revealed 830 articles, of which 766 were excluded leaving 64 candidate articles for the Delphi process. These 64 articles were organized by clinical domain including: emergency/neurology, cardiopulmonary, nephrology/fluids, infectious diseases, metabolic, immunomodulation, and nutrition/gastroenterology. Each domain required the a priori defined three Delphi rounds. The resultant most impactful articles from each domain included five randomized controlled trials and two systematic review/meta-analyses. Topics studied included sedation during mechanical ventilation, anticoagulation in COVID-19, extended infusion beta-lactams, interleukin-6 antagonists in COVID-19, balanced crystalloid resuscitation, vitamin C/thiamine/hydrocortisone in sepsis, and promotility agents during enteral feeding.

CONCLUSIONS

This synoptic review provides a summary and perspective of the most impactful articles relevant to the pharmacotherapy of critically ill adults published in 2021.

Gastrointestinal Dysmotility in Critically Ill Patients: Bridging the Gap Between Evidence and Common Misconceptions

Disruption of normal gastrointestinal (GI) function in critical illness is linked to increased morbidity and mortality, and GI dysmotility is frequently observed in patients who are critically ill. Despite its high prevalence, the diagnosis and management of GI motility problems in the intensive care unit remain very challenging, given that critically ill patients often cannot verbalize symptoms and the general lack of understanding of underlying pathophysiology. Common clinical presentations of GI dysmotility issues among critically ill patients include: (1) high gastric residual volumes, acid reflux, and vomiting, (2) abdominal distention, and (3) diarrhea. In this review, we discuss the differential diagnosis for intensive care unit patients with symptoms and signs concerning GI motility issues. There are many myths and longstanding misconceptions about the diagnosis and management of GI dysmotility in critical illness. Here, we uncover these myths and discuss relevant evidence in each subject area, with the goal of re-conceptualizing GI motility disorders in critical care and providing evidence-based recommendations for clinical care.

Efficacy and Safety of Enteral Erythromycin Estolate in Combination With Intravenous Metoclopramide vs Intravenous Metoclopramide Monotherapy in Mechanically Ventilated Patients With Enteral Feeding Intolerance: A Randomized, Double-Blind, Controlled Pilot Study

BACKGROUND

In this pilot study, we aimed to determine the efficacy and safety of enteral erythromycin estolate in combination with intravenous metoclopramide compared to intravenous metoclopramide monotherapy in mechanically ventilated patients with enteral feeding intolerance.

METHODS

This randomized, double-blind, controlled pilot study included 35 mechanically ventilated patients with feeding intolerance who were randomly assigned to receive 10-mg metoclopramide intravenously every 6-8 hours in combination with 250-mg enteral erythromycin estolate (study group) or placebo every 6 hours for 7 days. The primary outcome was an administered-to-target energy ratio of ≥80% at 48 hours, indicating a successful feeding. Secondary, prespecified outcomes were daily average gastric residual volume (GRV), total energy intake, administered-to-target energy ratio, hospital length of stay, in-hospital mortality, and 28-day mortality.

RESULTS

The rate of successful feeding was not significantly different between the study and placebo groups (47.1% and 61.1%, respectively; P = .51). The average daily GRV was significantly lower in the study group than in the placebo group (β = 91.58 [95% Wald CI, -164.35 to -18.8]), determined by generalized estimating equation. Other secondary outcomes were comparable, and the incidence of adverse events was not significantly different between the 2 groups. One common complication was cardiac arrhythmia, which was mostly self-terminated.

CONCLUSION

Although the combination therapy of enteral erythromycin estolate and intravenous metoclopramide reduced GRV, the successful feeding rate and other patient-specific outcomes did not improve in mechanically ventilated patients with feeding intolerance.

Blinded, Double-Dummy, Parallel-Group, Phase 2a Randomized Clinical Trial to Evaluate the Efficacy and Safety of a Highly Selective 5-Hydroxytryptamine Type 4 Receptor Agonist in Critically Ill Patients With Enteral Feeding Intolerance

Background

Delayed gastric emptying is the leading cause of enteral feeding intolerance (EFI) in critical illness. This phase 2a study compared TAK‐954, a selective agonist of 5‐hydroxytryptamine type 4 receptors, with metoclopramide in critically ill patients with EFI (NCT01953081).

Methods

A blinded, double‐dummy trial was conducted in mechanically ventilated patients with EFI (>200 mL gastric residual volume within 24 hours before randomization). Patients were randomized to receive either 0.5 mg intravenous TAK‐954 over 1 hour then 0.9% saline injection 4 times/d (sham metoclopramide) or the active comparator 10 mg intravenous metoclopramide 4 times/d and a 1‐hour 0.9% saline infusion. After initial dosing, participants received a radiolabeled meal of liquid nutrient (Ensure; 106 kcal), and gastric emptying was measured (scintigraphy). Adverse events (AEs) were recorded from the time of consent through to day 5; serious AEs were collected to day 30.

Results

Thirteen patients (TAK‐954, n = 7; metoclopramide, n = 6) participated. Five patients in the TAK‐954 group and 4 in the metoclopramide group experienced AEs (2 and 3, respectively, were serious). All AEs except 1 (diarrhea in the metoclopramide group) were considered unrelated to study drug. Following treatment, a greater proportion of patients receiving TAK‐954 had normal gastric retention (<13% retention at 180 minutes) than those receiving metoclopramide (6/7 vs 3/6 patients, respectively).

Conclusion

A single dose of 0.5 mg intravenous TAK‐954 appears to have at least similar efficacy in accelerating gastric emptying to multiple doses of 10 mg metoclopramide and was not associated with increased AEs.

Clinical Nutrition in Critical Care Medicine - Guideline of the German Society for Nutritional Medicine (DGEM)

PURPOSE

Enteral and parenteral nutrition of adult critically ill patients varies in terms of the route of nutrient delivery, the amount and composition of macro- and micronutrients, and the choice of specific, immune-modulating substrates. Variations of clinical nutrition may affect clinical outcomes. The present guideline provides clinicians with updated consensus-based recommendations for clinical nutrition in adult critically ill patients who suffer from at least one acute organ dysfunction requiring specific drug therapy and/or a mechanical support device (e.g., mechanical ventilation) to maintain organ function.

METHODS

The former guidelines of the German Society for Nutritional Medicine (DGEM) were updated according to the current instructions of the Association of the Scientific Medical Societies in Germany (AWMF) valid for a S2k-guideline. According to the S2k-guideline classification, no systematic review of the available evidence was required to make recommendations, which, therefore, do not state evidence- or recommendation grades. Nevertheless, we considered and commented the evidence from randomized-controlled trials, meta-analyses and observational studies with adequate sample size and high methodological quality (until May 2018) as well as from currently valid guidelines of other societies. The liability of each recommendation was described linguistically. Each recommendation was finally validated and consented through a Delphi process.

RESULTS

In the introduction the guideline describes a) the pathophysiological consequences of critical illness possibly affecting metabolism and nutrition of critically ill patients, b) potential definitions for different disease phases during the course of illness, and c) methodological shortcomings of clinical trials on nutrition. Then, we make 69 consented recommendations for essential, practice-relevant elements of clinical nutrition in critically ill patients. Among others, recommendations include the assessment of nutrition status, the indication for clinical nutrition, the timing and route of nutrient delivery, and the amount and composition of substrates (macro- and micronutrients); furthermore, we discuss distinctive aspects of nutrition therapy in obese critically ill patients and those treated with extracorporeal support devices.

CONCLUSION

The current guideline provides clinicians with up-to-date recommendations for enteral and parenteral nutrition of adult critically ill patients who suffer from at least one acute organ dysfunction requiring specific drug therapy and/or a mechanical support device (e.g., mechanical ventilation) to maintain organ function. The period of validity of the guideline is approximately fixed at five years (2018-2023).

Enteral tolerance in critically ill patients

Enteral nutrition (EN) can maintain the structure and function of the gastrointestinal mucosa better than parenteral nutrition. In critically ill patients, EN must be discontinued or interrupted, if gastrointestinal complications, particularly vomiting and bowel movement disorders, do not resolve with appropriate management. To avoid such gastrointestinal complications, EN should be started as soon as possible with a small amount of EN first and gradually increased. EN itself may also promote intestinal peristalsis. The measures to decrease the risk of reflux and aspiration include elevation the head of the bed (30° to 45°), switch to continuous administration, administration of prokinetic drugs or narcotic antagonists to promote gastrointestinal motility, and switch to jejunal access (postpyloric route). Moreover, the control of bowel movement is also important for intensive care and management. In particular, prolonged diarrhea can cause deficiency in nutrient absorption, malnutrition, and increase in mortality. In addition, diarrhea may cause a decrease the circulating blood volume, metabolic acidosis, electrolyte abnormalities, and contamination of surgical wounds and pressure ulcers. If diarrhea occurs in critically ill patients on EN management, it is important to determine whether diarrhea is EN-related or not. After ruling out the other causes of diarrhea, the measures to prevent EN-related diarrhea include switch to continuous infusion, switch to gastric feeding, adjustment of agents that improve gastrointestinal peristalsis or laxative, administration of antidiarrheal drugs, changing the type of EN formula, and semisolidification of EN formula. One of the best ways to success for EN management is to continue as long as possible without interruption and discontinuation of EN easily by appropriate measures, even if gastrointestinal complications occur.

Trends and Development in Enteral Nutrition Application for Ventilator Associated Pneumonia: A Scientometric Research Study (1996-2018)

Background: This study aimed to explore the intellectual landscape of the studies investigating the clinical application of enteral nutrition (EN) in patients with ventilator associated pneumonia (VAP), and to identify thematic development trends and research frontiers in this area.

Methods: Scientometric research was conducted by analyzing bibliographic records retrieved from the Web of Science Core Collection Database dated between 1996 and 2018. Reference co-citation analysis, key words co-occurrence analysis and cooperation network analysis were performed using CiteSpace software.

Results: A total of 124 valid records were included in the final dataset. It was found that early studies were mainly focused on the feeding pathways of EN among VAP patients. The risks associated with EN intervention in VAP patients, including gastric nutrition intolerance and aspiration pneumonia, were extensively investigated and reported. While aspiration pneumonia has remained a long-term active research area in the field of EN interventions for VAP patients, with recent research focused more on interventions aiming to improve EN support and to optimize the use of EN for VAP patients. It seems that clinical guidelines on EN interventions for VAP patients need to be established.

Conclusion: The advantages of EN for VAP patients have been recognized but still require further investigation on standardizing the use. Strategic cooperation among hospital physicians, university researchers and industrial product developers is required to establish clinical guidelines and to continue developing innovative EN products to tackle VAP.

Optimizing early enteral nutrition in severe stroke (OPENS): protocol for a multicentre randomized controlled trial

Background

Malnutrition is one of the crucial factors associated with poor prognosis in critical ill patients, yet a significant evidence gap surrounds the management of initial enteral feeding in severe stroke. The Optimizing Early Enteral Nutrition in Severe Stroke (OPENS) trial will compare a strategy of modified full enteral nutrition (EN) (standard full EN in conjunction with prokinetic drug) and a strategy of permissive underfeeding (40 to 60% of estimated caloric requirements) with standard full EN (advancement to target nutrition goals) in patients with severe stroke.

Methods

The OPENS trial is a multicenter randomized controlled study. A total of 600 adult patients with severe stroke will be enrolled in 12 study sites in China, and randomized to standard full EN, modified full EN, or permissive underfeeding. The primary outcome measurement is the proportion of participants with a poor outcome (modified Rankin Scale ≥3) at day 90 of enrollment. Secondary outcomes include incidence rates of complications during hospitalization, disability at hospital discharge, and the ability of activities of daily living at day 90 of enrollment. The relationship between intervention and the primary outcome will be analyzed using multivariate logistic regression adjusted for study site, demographics, and baseline characteristics.

Discussion

The OPENS trial will explore the optimum initial feeding strategy for acute severe stroke. This trial is, therefore, an important step in bridging the evidence gap surrounding the enteral feeding for patients with severe stroke during the first week of hospitalization.

Trial registration

ClinicalTrials.gov Identifier: NCT02982668; First Posted: December 5, 2016.

Pathophysiology and Treatment of Gastrointestinal Motility Disorders in the Acutely Ill

Gastrointestinal dysmotility causes delayed gastric emptying, enteral feed intolerance, and functional obstruction of the small and large intestine, the latter functional obstructions being frequently termed ileus and Ogilvie syndrome, respectively. In addition to meticulous supportive care, drug therapy may be appropriate in certain situations. There is, however, considerable variation among individuals regarding what gastric residual volume identifies gastric dysmotility and would encourage use of a promotility drug. While the administration of either metoclopramide or erythromycin is supported by evidence it appears that, dual-drug therapy (erythromycin and metoclopramide) reduces the rate of treatment failure. There is a lack of evidence to guide drug therapy of ileus, but neither erythromycin nor metoclopramide appear to have a role. Several drugs, including ghrelin agonists, highly selective 5-hydroxytryptamine receptor agonists, and opiate antagonists are being studied in clinical trials. Neostigmine, when infused at a relatively slow rate in patients receiving continuous hemodynamic monitoring, may alleviate the need for endoscopic decompression in some patients.

In Search of the Ideal Promotility Agent: Optimal Use of Currently Available Promotility Agents for Nutrition Therapy of the Critically Ill Patient

PURPOSE OF REVIEW

Enteral nutrition therapy is essential in the management of critically ill patients. Prokinetic agents have been used successfully to aid in the delivery of nutrition and improve feeding tolerance in patients in the intensive care unit (ICU). The aim of this report is to review the existing promotility agents available for use in the critically ill as well as outline the role of potential investigative drugs in order to provide a guide to the management of this difficult and important clinical dilemma.

RECENT FINDINGS

While no single currently available agent currently meets all of the desired goals in the critical care setting, there are an increasing number of available agents from which to choose including motilin receptor agonists, 5HT4 receptor agonists, D2 receptor antagonists, and Mu opioid receptor antagonists. We recommend a multifaceted approach to optimizing enteral nutrition in the critical care setting which should include the early, prophylactic use of promotility agents and should focus on the management of reversible causes of impaired gastrointestinal motility.

Nutrition Therapy in Sepsis

Sepsis is characterized by early massive catabolism, lean body mass (LBM) loss, and escalating hypermetabolism persisting for months to years. Early enteral nutrition should attempt to correct micronutrient/vitamin deficiencies, deliver adequate protein and moderated nonprotein calories, as well-nourished patients can generate reasonable endogenous energy. After resuscitation, increasing protein/calories are needed to attenuate LBM loss and promote recovery. Malnutrition screening is essential, and parenteral nutrition can be safely added when enteral nutrition is failing based on preillness malnutrition. Following discharge from intensive care unit, significantly increased protein/calorie delivery is required for months to years to facilitate functional and LBM recovery.

Metoclopramide as intermittent and continuous infusions in critically ill patients: a pilot randomized clinical trial

AIM

Metoclopramide is commonly used as a prokinetic agent in critically ill patients with enteral feeding intolerance. In this study, noninferiority of metoclopramide as intermittent versus continuous infusion was examined in critically ill patients with enteral feeding intolerance.

METHODS

Forty critically ill adults patients were assigned to receive metoclopramide as either intermittent (10 mg every 6 h) or continuous (2 mg/h) infusion. Frequency of feeding intolerance and adverse effects of metoclopramide were assessed during 7 days of study.

RESULTS

Number of patients with feeding intolerance during different times of the course was not different between the groups. Although not statistically significant, diarrhea and cardiac rhythm were more common in continuous than intermittent infusion group.

CONCLUSION

Continuous and intermittent infusions of metoclopramide showed equivalent effectiveness in critically ill patients.

ASPEN Safe Practices for Enteral Nutrition Therapy [Formula: see text]

Enteral nutrition (EN) is a valuable clinical intervention for patients of all ages in a variety of care settings. Along with its many outcome benefits come the potential for adverse effects. These safety issues are the result of clinical complications and of process-related errors. The latter can occur at any step from patient assessment, prescribing, and order review, to product selection, labeling, and administration. To maximize the benefits of EN while minimizing adverse events requires that a systematic approach of care be in place. This includes open communication, standardization, and incorporation of best practices into the EN process. This document provides recommendations based on the available evidence and expert consensus for safe practices, across each step of the process, for all those involved in caring for patients receiving EN.

Gastrointestinal dysmotility in the critically ill: a role for nutrition

PURPOSE OF REVIEW

The role of enteral nutrition on gastrointestinal dysmotility in the critically ill remains controversial.

RECENT FINDINGS

The mechanisms of gastrointestinal dysmotility during critical illness remain poorly investigated. Low amounts of enteral feeding stimulate motility and have trophic effects. Therefore, enteral feeding is feasible even during gastrointestinal dysmotility as seen in the hemodynamically compromised patient. Rapid 'ramp-up' of administration rate of tube feeding bears the risk of overload and even detrimental ischemic bowel necrosis. The recent American Society for Parenteral and Enteral Nutrition guidelines do not recommend the measurement of gastric residual volume. The use of concentrated enteral solutions with 1.5 kcal/ml may result in greater calorie delivery. Biomarkers like plasma citrulline and plasma or urine intestinal fatty-acid-binding protein reflect the functional integrity of the bowel and may potentially support monitoring.

SUMMARY

To improve enteral nutrition protocols, the definitions of gastrointestinal dysfunction, gastric dysmotility, and feeding intolerance should be clearly defined in the future. In the concept of integrity of the gut, enteral nutrition should not be stopped completely during gastrointestinal dysfunction but restricted to a 'minimal' trophic feeding rate. In malnourished and high-risk patients intolerant to enteral feeding supplemental parenteral nutrition should be started on day 4 or earlier.

The efficacy and safety of prokinetic agents in critically ill patients receiving enteral nutrition: a systematic review and meta-analysis of randomized trials

Background

Intolerance to enteral nutrition is common in critically ill adults, and may result in significant morbidity including ileus, abdominal distension, vomiting and potential aspiration events. Prokinetic agents are prescribed to improve gastric emptying. However, the efficacy and safety of these agents in critically ill patients is not well-defined. Therefore, we conducted a systematic review and meta-analysis to determine the efficacy and safety of prokinetic agents in critically ill patients.

Methods

We searched MEDLINE, EMBASE, and Cochrane Library from inception up to January 2016. Eligible studies included randomized controlled trials (RCTs) of critically ill adults assigned to receive a prokinetic agent or placebo, and that reported relevant clinical outcomes. Two independent reviewers screened potentially eligible articles, selected eligible studies, and abstracted pertinent data. We calculated pooled relative risk (RR) for dichotomous outcomes and mean difference for continuous outcomes, with the corresponding 95 % confidence interval (CI). We assessed risk of bias using Cochrane risk of bias tool, and the quality of evidence using grading of recommendations assessment, development, and evaluation (GRADE) methodology.

Results

Thirteen RCTs (enrolling 1341 patients) met our inclusion criteria. Prokinetic agents significantly reduced feeding intolerance (RR 0.73, 95 % CI 0.55, 0.97; P = 0.03; moderate certainty), which translated to 17.3 % (95 % CI 5, 26.8 %) absolute reduction in feeding intolerance. Prokinetics also reduced the risk of developing high gastric residual volumes (RR 0.69; 95 % CI 0.52, 0.91; P = 0.009; moderate quality) and increased the success of post-pyloric feeding tube placement (RR 1.60, 95 % CI 1.17, 2.21; P = 0.004; moderate quality). There was no significant improvement in the risk of vomiting, diarrhea, intensive care unit (ICU) length of stay or mortality. Prokinetic agents also did not significantly increase the rate of diarrhea.

Conclusion

There is moderate-quality evidence that prokinetic agents reduce feeding intolerance in critically ill patients compared to placebo or no intervention. However, the impact on other clinical outcomes such as pneumonia, mortality, and ICU length of stay is unclear.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1441-z) contains supplementary material, which is available to authorized users.

The effect of camicinal (GSK962040), a motilin agonist, on gastric emptying and glucose absorption in feed-intolerant critically ill patients: a randomized, blinded, placebo-controlled, clinical trial

Background

The promotility agents currently available to treat gastroparesis and feed intolerance in the critically ill are limited by adverse effects. The aim of this study was to assess the pharmacodynamic effects and pharmacokinetics of single doses of the novel gastric promotility agent motilin agonist camicinal (GSK962040) in critically ill feed-intolerant patients.

Methods

A prospective, randomized, double-blind, parallel-group, placebo-controlled, study was performed in mechanically ventilated feed-intolerant patients [median age 55 (19–84), 73 % male, APACHE II score 18 (5–37) with a gastric residual volume ≥200 mL]. Gastric emptying and glucose absorption were measured both pre- and post-treatment after intragastric administration of 50 mg (n = 15) camicinal and placebo (n = 8) using the ¹³C-octanoic acid breath test (BTt_1/2), acetaminophen concentrations, and 3-O-methyl glucose concentrations respectively.

Results

Following 50 mg enteral camicinal, there was a trend to accelerated gastric emptying [adjusted geometric means: pre-treatment BTt_1/2 117 minutes vs. post- treatment 76 minutes; 95 % confidence intervals (CI; 0.39, 1.08) and increased glucose absorption (AUC_240min pre-treatment: 28.63 mmol.min/L vs. post-treatment: 71.63 mmol.min/L; 95 % CI (1.68, 3.72)]. When two patients who did not have detectable plasma concentrations of camicinal were excluded from analysis, camicinal accelerated gastric emptying (adjusted geometric means: pre-treatment BTt_1/2 121 minutes vs. post-treatment 65 minutes 95 % CI (0.32, 0.91) and increased glucose absorption (AUC_240min pre-treatment: 33.04 mmol.min/L vs. post-treatment: 74.59 mmol.min/L; 95 % CI (1.478, 3.449). In those patients receiving placebo gastric emptying was similar pre- and post-treatment.

Conclusions

When absorbed, a single enteral dose of camicinal (50 mg) accelerates gastric emptying and increases glucose absorption in feed-intolerant critically ill patients.

Trial registration

The study protocol was registered with the US NIH clinicaltrials.gov on 23 December 2009 (Identifier NCT01039805).

Acetaminophen absorption kinetics in altered gastric emptying: establishing a relevant pharmacokinetic surrogate using published data

Acetaminophen has been used as a tool for clinical and nonclinical experimental designs that evaluate gastric emptying because acetaminophen is not absorbed in stomach but efficiently absorbed from the small intestine. Published pharmacokinetic data of acetaminophen in subjects with normal gastric emptying vs. impaired gastric emptying (i.e., morphine treatment) were evaluated to select a key surrogate. Using Caverage (average concentration), computed from the exposure within the first hour, individual rank distribution was plotted across different studies. Caverage was highly correlated with Cmax (maximum concentration) in subjects with normal gastric emptying (R(2) = .7532) but not in those where gastric emptying was impaired (R(2) = .0213). The 50th percentile value of the distribution pattern of 1/Caverage in acetaminophen+morphine-treated group (coincided with the first shift in the slope) was considered as the cutoff point to figure out the impaired gastric emptying. The individual rank distribution plots for 1/Caverage across different studies supported similar trends in subjects with normal gastric emptying but showed a distinct distribution pattern in the cohort of impaired gastric emptying. Caverage, calculated within the first hour of dosing of acetaminophen (average concentration at 0-1 hour, C0-1havg), can be used as a key surrogate to distinguish the effects of gastric emptying on the absorption of acetaminophen. A 4 μg/mL C0-1havg of acetaminophen (dose: 1.5 g) may be used as cutoff point in future clinical investigations of acetaminophen to clarify the role of gastric emptying.

Effect of Critical Illness on Triglyceride Absorption

BACKGROUND

Adequate nutrition support for critically ill patients optimizes outcome, and enteral feeding is the preferred route of nutrition. Small intestinal glucose absorption is frequently impaired in critical illness. Despite lipid being a major constituent of liquid nutrient administered, there is little information about lipid absorption during critical illness.

OBJECTIVES

To determine small intestinal lipid, as well as glucose, absorption in critical illness compared with health.

MATERIALS AND METHODS

Twenty-nine mechanically ventilated critically ill patients and 16 healthy volunteers were studied. Liquid nutrient (60 mL, 1 kcal/mL), containing 200 µL (13)C-triolein and 3 g 3-O-methyl-glucose (3-OMG), was infused directly into the duodenum at a rate of 2 kcal/min. Exhaled (13)CO2 and serum 3-OMG concentrations were measured at timed intervals over 360 minutes. Lipid absorption was measured as the cumulative percentage dose (cPDR) of (13)CO2 recovered at 360 minutes. Glucose absorption was measured as the area under the 3-OMG concentration curve. Data are median (range) and analyzed using the Mann-Whitney U and Pearson correlation tests.

RESULTS

Lipid absorption was markedly less in the critically ill (cPDR(13)CO2: patients, 22.6% [0%-100%] vs healthy participants, 40.7% [5.3%-84.7%]; P = .018). While glucose absorption was less at 60 minutes in the critically ill (3-OMG60: 13.2 [3.5-29.5] vs 21.1 [9.3-31.9] mmol/L·min; P = .003), this was not apparent at 360 minutes (3-OMG360: 92.7 [54.5-147.9] vs 107.9 [64.0-168.7] mmol/L·min; P = .126). There was no relationship between lipid and glucose absorption.

CONCLUSION

Small intestinal absorption of lipid is diminished during critical illness.

Gastric Dysmotility in Critically Ill Children: Pathophysiology, Diagnosis, and Management

OBJECTIVE

We aimed to review gastric dysmotility in critically ill children: 1) its pathophysiology, with a focus on critical care diseases and therapies that affect gastric motility, 2) diagnostic methodologies, and 3) current and future potential therapies.

DATA SOURCES

Eligible studies were identified from PubMed and MEDLINE.

STUDY SELECTION

Literature search included the following key terms: "gastric emptying," "gastric motility/dysmotility," "gastrointestinal motility/dysmotility," "nutrition intolerance," and "gastric residual volume."

DATA EXTRACTION

Studies since 1995 were extracted and reviewed for inclusion by the authors related to the physiology, pathophysiology, diagnostic methodologies, and available therapies for gastric emptying.

DATA SYNTHESIS

Delayed gastric emptying, a common presentation of gastric dysmotility, is present in up to 50% of critically ill children. It is associated with the potential for aspiration, ventilator-associated pneumonia, and inadequate delivery of enteral nutrition and may affect the efficacy of enteral medications, all of which may be result in poor patient outcomes. Gastric motility is affected by critical illness and its associated therapies. Currently available diagnostic tools to identify gastric emptying at the bedside have not been systematically studied and applied in this cohort. Gastric residual volume measurement, used as an indirect marker of delayed gastric emptying in PICUs around the world, may be inaccurate.

CONCLUSIONS

Gastric dysmotility is common in critically ill children and impacts patient safety and outcomes. However, it is poorly understood, inadequately defined, and current therapies are limited and based on scant evidence. Understanding gastric motility and developing accurate bedside measures and novel therapies for gastric emptying are highly desirable and need to be further investigated.

Interruptions in enteral nutrition delivery in critically ill patients and recommendations for clinical practice

Malnutrition is common in critically ill patients and is associated with poor outcomes for patients and increased health care spending. Enteral nutrition is the method of choice for nutrition delivery. Enteral nutrition delivery practices vary widely, and underfeeding is widespread in critical care. Interruptions in enteral nutrition due to performance of procedures, positioning, technical issues with feeding accesses, and gastrointestinal intolerance contribute to underfeeding. Strategies such as head-of-bed positioning, use of prokinetic agents, tolerance of higher gastric residual volumes, consideration of postpyloric feeding access, and use of a nutrition support protocol may decrease time spent without nutrition.

Measurement of gastric emptying in the critically ill

BACKGROUND & AIMS

Enteral nutrition is important in critically ill patients and is usually administered via a nasogastric tube. As gastric emptying is frequently delayed, and this compromises the delivery of nutrient, it is important that the emptying rate can be quantified.

METHODS

A comprehensive search of MEDLINE/PubMed, of English articles, from inception to 1 July 2014. References of included manuscripts were also examined for additional studies.

RESULTS

A number of methods are available to measure gastric emptying and these broadly can be categorised as direct- or indirect-test and surrogate assessments. Direct tests necessitate visualisation of the stomach contents during emptying and are unaffected by liver or kidney metabolism. The most frequently used direct modality is scintigraphy, which remains the 'gold standard'. Indirect tests use a marker that is absorbed in the proximal small intestine, so that measurements of the marker, or its metabolite measured in plasma or breath, correlates with gastric emptying. These tests include drug and carbohydrate absorption and isotope breath tests. Gastric residual volumes (GRVs) are used frequently to quantify gastric emptying during nasogastric feeding, but these measurements may be inaccurate and should be regarded as a surrogate measurement. While the inherent limitations of GRVs make them less suitable for research purposes they are often the only technique that is available for clinicians at the bedside.

CONCLUSIONS

Each of the available techniques has its strength and limitations. Accordingly, the choice of gastric emptying test is dictated by the particular requirement(s) and expertise of the investigator or clinician.

Metoclopramide or domperidone improves post-pyloric placement of spiral nasojejunal tubes in critically ill patients: a prospective, multicenter, open-label, randomized, controlled clinical trial

INTRODUCTION

The use of prokinetic agents on post-pyloric placement of spiral nasojejunal tubes is controversial. The aim of the present study was to examine if metoclopramide or domperidone can increase the success rate of post-pyloric placement of spiral nasojejunal tubes.

METHODS

A multicenter, open-label, randomized, controlled trial was conducted in seven hospitals in China between April 2012 and February 2014. Patients admitted to the intensive care unit and requiring enteral nutrition for more than three days were randomly assigned to the metoclopramide, domperidone or control groups (1:1:1 ratio). The primary outcome was defined as the success rate of post-pyloric placement of spiral nasojejunal tubes, assessed 24 hours after initial placement. Secondary outcomes included success rate of post-D1, post-D2, post-D3 and proximal jejunum placement and tube migration distance. Safety of the study drugs and the tubes during the entire study period were recorded.

RESULTS

In total, 307 patients were allocated to the metoclopramide (n = 103), domperidone (n = 100) or control group (n = 104). The success rate of post-pyloric placement after 24 hours in the metoclopramide, domperidone and control groups was 55.0%, 51.5% and 27.3%, respectively (P = 0.0001). Logistic regression analysis identified the use of prokinetic agents, Acute Physiology and Chronic Health Evaluation (APACHE) II score <20, Sequential Organ Failure Assessment (SOFA) score <12 and without vasopressor as independent factors influencing the success rate of post-pyloric placement. No serious drug-related adverse reaction was observed.

CONCLUSIONS

Prokinetic agents, such as metoclopramide or domperidone, are effective at improving the success rate of post-pyloric placement of spiral nasojejunal tubes in critically ill patients.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR-TRC-12001956 . Registered 21 February 2012.

A practice change initiative to improve the provision of enteral nutrition to intensive care patients

AIM

To describe a practice change initiative that improved the provision of enteral nutrition (EN) to patients in a New Zealand tertiary intensive care unit (ICU).

METHODS

The project reviewed and summarized EN literature, amended local policy, and an evidence-based EN delivery algorithm was developed. The EN practice change initiative was implemented and evaluated. Data was collected and analyzed in a pre-audit (2009) and a post-audit (2013).

RESULTS

Comparison of the pre-audit (N = 25) and the post-audit (N = 40) data demonstrated improvements in three areas of EN delivery. The commencement of early EN within 24 h of admission was evident for a large proportion of patients in both 2009 and 2013 audits. There was a large reduction in time between the two audits for both ICU admission to achievement of EN goal rate (M = 57·71 h versus M = 33·79 h, p = 0·006) and also for EN commencement to achievement of EN goal rate (M = 31·65 h versus M = 10·15 h, p = 0·000). The volume of prescribed EN delivered on days 2, 4 and 6 was greater in the 2013 audit in comparison to the 2009 audit. Staff compliance with adhering to the EN policy and algorithm improved from 46% in 2009, to 95% in 2013.

CONCLUSIONS

The practice change has significantly improved the practice delivery of EN for patients in the local ICU resulting in optimal care.

RELEVANCE TO CLINICAL PRACTICE

Malnutrition is highly prevalent among intensive care patients. Strategies and initiatives that improve the delivery of enteral nutrition to the critical care population is therefore vitally important. This article describing such an initiative is thus highly relevant to all health care professionals delivering enteral nutrition in intensive and critical care units.

Prevalence, risk factors, clinical consequences, and treatment of enteral feed intolerance during critical illness

BACKGROUND

We aimed to determine the incidence of enteral feed intolerance and factors associated with intolerance and to assess the influence of intolerance on nutrition and clinical outcomes.

METHODS

We conducted a retrospective analysis of data from an international observational cohort study of nutrition practices among 167 intensive care units (ICUs). Data were collected on nutrition adequacy, ventilator-free days (VFDs), ICU stay, and 60-day mortality. Intolerance was defined as interruption of enteral nutrition (EN) due to gastrointestinal (GI) reasons (large gastric residuals, abdominal distension, emesis, diarrhea, or subjective discomfort). Logistic regression was used to determine risk factors for intolerance and their clinical significance. A sensitivity analysis restricted to sites specifying a gastric residual volume ≥200 mL to identify intolerance was also conducted.

RESULTS

Data from 1,888 ICU patients were included. The incidence of intolerance was 30.5% and occurred after a median 3 days from EN initiation. Patients remained intolerant for a mean (±SD) duration of 1.9 ± 1.3 days . Intolerance was associated with worse nutrition adequacy vs the tolerant (56% vs 64%, P < .0001), fewer VFDs (2.5 vs 11.2, P < .0001), increased ICU stay (14.4 vs 11.3 days, P < .0001), and increased mortality (30.8% vs 26.2, P = .04). The sensitivity analysis demonstrated that intolerance remained associated with negative outcomes. Although mortality was greater among the intolerant patients, this was not statistically significant.

CONCLUSIONS

Intolerance occurs frequently during EN in critically ill patients and is associated with poorer nutrition and clinical outcomes.

Gastroesophageal reflux in critically ill patients

Gastroesophageal reflux (GER) is a common occurrence in critically ill, mechanically ventilated patients. Reflux can lead to pulmonary aspiration of gastric contents and subsequent pneumonia. Several characteristics of patients, interventions provided in the intensive care unit setting, and factors associated with feeding increase a patient's risk for reflux. Critical care nurses and clinical nurse specialists can identify patients at highest risk for GER by utilizing the patient's history, reviewing the medications, and assessing the current status to provide interventions to reduce the risk of GER and its sequelae of aspiration pneumonia. This article reviews the physiology of GER, risk factors, and interventions to decrease GER in the critically ill patient.