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.

Modified low ratio ketogenic therapy in the treatment of adults with super-refractory status epilepticus

BACKGROUND

Induction of ketosis by manipulation of nutrition intake has been proposed as an adjunctive treatment for super-refractory status epilepticus (SRSE). However, the classical 4:1 ketogenic ratio may not meet the nutrition needs, specifically protein for critically ill adults. The aim of this study was to analyze the outcomes of adults with SRSE who received a lower ketogenic ratio of 2:1 grams of fat to non-fat grams, including 20%-30% of energy from medium chain triglycerides.

METHODS

We reviewed patients aged ≥18 years with SRSE treated with ketogenic therapy between July 2015 and December 2020 at two quaternary teaching hospitals in Melbourne, Australia. Data collected from medical records included patient demographics, nutrition prescription, clinical outcomes, and ketogenic therapy-related complications. The primary outcome of the study was to assess tolerability of ketogenic therapy.

RESULTS

Twelve patients (female = 7) were treated with ketogenic therapy for SRSE. Patients received between 4 and 8 antiseizure medications and 1-5 anesthetic agents prior to commencement of ketogenic therapy. Blood beta-hydroxybutyrate concentrations were variable (median = 0.5 mmol/L, range: 0.0-6.1 mmol/L). SRSE resolved in 10 cases (83%) after a median of 9 days (range: 2-21 days) following commencement of ketogenic therapy. Ketogenic therapy-associated complications were reported in five patients, leading to cessation in two patients.

CONCLUSION

Despite the challenge in maintaining ketosis during critical illness, low ratio 2:1 ketogenic therapy incorporating medium chain triglycerides is tolerable for adults with SRSE. Further studies are required to determine the optimal timing, nutrition prescription and duration of ketogenic therapy for SRSE treatment.

[Gastrointestinal motility disorders in critically ill patients]

The gastrointestinal tract is one of the most complex organ systems of the human body. On the one hand, it forms the absorption surface for nutrients, but on the other hand it is also a barrier for toxins, food components and against up to 10¹⁴ commensal microorganisms. The complexity of the interplay between absorption, motility and immune functions of the gastrointestinal tract is particularly evident in critically ill patients. In this article, we review the latest updates on pathogenic relationships of motility disorders and diagnostic algorithms in intensive care patients. In addition to established therapies, new developments in the treatment of hypomotility are outlined.

Preventive strategies for feeding intolerance among patients with severe traumatic brain injury: A cross-sectional survey

Objectives

This study aimed to investigate the application status of preventive measures for feeding intolerance in patients with severe traumatic brain injury (STBI) in China and analysis the differences and their causes.

Methods

A cross-sectional survey was conducted. From December 2019 to January 2020, ICU nurses and physicians of 89 hospitals in China were surveyed by using a questionnaire on preventive strategies for feeding intolerance in patients with STBI. The questionnaire included two parts: the general information of participants (10 items) and application of preventive measures for feeding intolerance in STBI patients (18 items).

Results

Totally 996 nurses and physicians completed the questionnaire. Among various methods, gastrointestinal symptoms(85.0%) and injury severity (71.4%) were mostly used to assess gastrointestinal functions and risk of feeding intolerance among STBI patients, respectively. Initiating enteral nutrition (EN) within 24–48 h (61.5%), nasogastric tubes (91.2%), 30°–45° of head-of-bed elevation (89.5%), continuous feeding by pump (72.9%), EN solution temperature of 38–40 °C (65.5%), <500 ml initial volume of EN solution (50.0%), monitoring gastric residual volume with a syringe (93.7%), and assessing gastric residual volume every 4 h (51.5%) were mostly applied for EN delivery among STBI patients. Prokinetic agents (73.3%), enema (73.6%), probiotics (79.0%), antacid agents (84.1%), and non-nutritional preparations as initial EN formula (65.6%) were commonly used for preventing feeding intolerance among STBI patients.

Conclusions

The survey showed that nurses and clinicians in China have a positive attitude towards preventive strategies for feeding intolerance. However, some effective new technologies and methods have not been timely applied in clinical practice. We suggest that managers, researchers, clinicians, nurses, and other health professionals should collaborate to explore effective and standard preventive strategies for feeding intolerance among patients with STBI.

The correlation between gastric residual volumes and markers of gastric emptying: a post-hoc analysis of a randomized clinical trial

BACKGROUND

The correlation between gastric residual volumes (GRV) and markers of gastric emptying (GE) in critically ill patients is unclear. This is especially true for ICU surgical patients as they are underrepresented in previous studies.

METHODS

We conducted a post-hoc analysis of a multicenter trial that investigated the effectiveness of a promotility drug in increasing enteral nutrition intake. Pharmacokinetic markers of GE [3-O-methylglucose (3-OMG) and acetaminophen] were correlated with GRV measurements. High-GRV was defined as one episode of >400 mL or two consecutive episodes of >250 mL, and delayed GE was defined as <20^th percentile of the pharmacokinetic GE marker that had the strongest correlation with GE.

RESULTS

Out of 77 patients, 8 (10.4%) had high-GRV, and 15 (19.5%) had delayed GE. 3-OMG concentration at 60 mins had the strongest correlation with GRV (Rho: - 0.631), and high-GRV had low sensitivity (46.7%) but high specificity (98.4%) in discriminating delayed GE. The positive (87.5%) and negative (88.4%) predictive values were similar. There was a small sample of surgical patients (n = 14, 18.2%), and they had a significantly higher incidence of high-GRV (29% vs 6%, P: 0.032) and a trend towards delayed GE (36% vs 16%, p: 0.132) when compared to medical patients.

CONCLUSION

GRV reflects GE, and high-GRV is an acceptable surrogate marker of delayed GE. Based on our preliminary observation, surgical patients may have a higher risk of high-GRV and delayed GE. In summary, GRV should be monitored to determine if complex investigations or therapeutic interventions are warranted. This article is protected by copyright. All rights reserved.

Incidence, Risk Factors, and Clinical Consequence of Enteral Feeding Intolerance in the Mechanically Ventilated Critically Ill: An Analysis of a Multicenter, Multiyear Database

OBJECTIVES

To determine the incidence of enteral feed intolerance, identify factors associated with enteral feed intolerance, and assess the relationship between enteral feed intolerance and key nutritional and clinical outcomes in critically ill patients.

DESIGN

Analysis of International Nutrition Survey database collected prospectively from 2007 to 2014.

SETTING

Seven-hundred eighty-five ICUs from around the world.

PATIENTS

Mechanically ventilated adults with ICU stay greater than or equal to 72 hours and received enteral nutrition during the first 12 ICU days.

INTERVENTIONS

None.

MEASUREMENT AND MAIN RESULTS

We defined enteral feed intolerance as interrupted feeding due to one of the following reasons: high gastric residual volumes, increased abdominal girth, distension, subjective discomfort, emesis, or diarrhea. The current analysis included 15,918 patients. Of these, 4,036 (24%) had at least one episode of enteral feed intolerance. The enteral feed intolerance rate increased from 1% on day 1 to 6% on days 4 and 5 and declined daily thereafter. After controlling for site and patient covariates, burn (odds ratio 1.46; 95% CIs, 1.07-1.99), gastrointestinal (odds ratio 1.45; 95% CI, 1.27-1.66), and sepsis (odds ratio 1.34; 95% CI, 1.17-1.54) admission diagnoses were more likely to develop enteral feed intolerance, as compared to patients with respiratory-related admission diagnosis. enteral feed intolerance patients received about 10% less enteral nutrition intake, as compared to patients without enteral feed intolerance after controlling for important covariates including severity of illness. Enteral feed intolerance patients had fewer ventilator-free days and longer ICU length of stay time to discharge alive (all p < 0.0001). The daily mortality hazard rate increased by a factor of 1.5 (1.4-1.6; p < 0.0001) once enteral feed intolerance occurred.

CONCLUSIONS

Enteral feed intolerance occurs frequently during enteral nutrition delivery in the critically ill. Burn and gastrointestinal patients had the highest risk of developing enteral feed intolerance. Enteral feed intolerance is associated with lower enteral nutrition delivery and worse clinical outcomes. Identification, prevention, and optimal management of enteral feed intolerance may improve nutrition delivery and clinical outcomes in important "at risk" populations.

Gut dysfunction in the ICU: diagnosis and management

PURPOSE OF REVIEW

Progress has been made in our understanding of gut dysfunction in critical illness. This review will outline new findings and give perspectives based on previous knowledge and concurrent advances in nutrition.

RECENT FINDINGS

The relationship between gut dysfunction and poor outcomes in critical illness has received considerable interest. It remains uncertain whether gut dysfunction is merely a marker of illness severity or if it is directly responsible for prolonged critical illness and increased mortality. This relationship is difficult to ascertain given there is no agreed method for identification and quantification; biomarkers such as intestinal fatty acid binding protein and citrulline show promise but require further study. Recent studies have investigated strategies to deliver enteral nutrition targets with impacts on gut function, including high calorie or protein formulae, intermittent regimes and novel prokinetics.

SUMMARY

Gut dysfunction is associated with poor outcomes, but it remains uncertain whether strategies to improve gut function will influence survival and recovery.

The efficacy and safety of prokinetics in critically ill adults receiving gastric feeding tubes: A systematic review and meta-analysis

Background

Intolerance to gastric feeding tubes is common among critically ill adults and may increase morbidity. Administration of prokinetics in the ICU is common. However, the efficacy and safety of prokinetics are unclear in critically ill adults with gastric feeding tubes. We conducted a systematic review to determine the efficacy and safety of prokinetics for improving gastric feeding tube tolerance in critically ill adults.

Methods

Randomized controlled trials (RCTs) were identified by systematically searching the Medline, Cochrane and Embase databases. Two independent reviewers extracted the relevant data and assessed the quality of the studies. We calculated pooled relative risks (RRs) for dichotomous outcomes and the mean differences (MDs) for continuous outcomes with the corresponding 95% confidence intervals (CIs). We assessed the risk of bias using the Cochrane risk-of-bias tool and used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology to rate the quality of the evidence.

Results

Fifteen RCTs met the inclusion criteria. A total of 10 RCTs involving 846 participants were eligible for the quantitative analysis. Most studies (10 of 13, 76.92%) showed that prokinetics had beneficial effects on feeding intolerance in critically ill adults. In critically ill adults receiving gastric feeding, prokinetic agents may reduce the ICU length of stay (MD -2.03, 95% CI -3.96, -0.10; P = 0.04; low certainty) and the hospital length of stay (MD -3.21, 95% CI -5.35, -1.06; P = 0.003; low certainty). However, prokinetics failed to improve the outcomes of reported adverse events and all-cause mortality.

Conclusion

As a class of drugs, prokinetics may improve tolerance to gastric feeding to some extent in critically ill adults. However, the certainty of the evidence suggesting that prokinetics reduce the ICU or hospital length of stay is low. Prokinetics did not significantly decrease the risks of reported adverse events or all-cause mortality among critically ill adults.

Promotion of Regular Oesophageal Motility to Prevent Regurgitation and Enhance Nutrition Intake in Long-Stay ICU Patients. A Multicenter, Phase II, Sham-Controlled, Randomized Trial: The PROPEL Study

OBJECTIVES

To evaluate the effect of esophageal stimulation on nutritional adequacy in critically ill patients at risk for enteral feeding intolerance.

DESIGN

A multicenter randomized sham-controlled clinical trial.

SETTING

Twelve ICUs in Canada.

PATIENTS

We included mechanically ventilated ICU patients who were given moderate-to-high doses of opioids and expected to remain alive and ventilated for an additional 48 hours and who were receiving enteral nutrition or expected to start imminently.

INTERVENTIONS

Patients were randomly assigned 1:1 to esophageal stimulation via an esophageal stimulating catheter (E-Motion Tube; E-Motion Medical, Tel Aviv, Israel) or sham treatment. All patients were fed via these catheters using a standardized feeding protocol.

MEASUREMENTS AND MAIN RESULTS

The co-primary outcomes were proportion of caloric and protein prescription received enterally over the initial 7 days following randomization. Among 159 patients randomized, the modified intention-to-treat analysis included 155 patients: 73 patients in the active treatment group and 82 in the sham treatment group. Over the 7-day study period, the percent of prescribed caloric intake (± SE) received by the enteral route was 64% ± 2 in the active group and 65% ± 2 in sham patients for calories (difference, -1; 95% CI, -8 to 6; p = 0.74). For protein, it was 57% ± 3 in the active group and 60% ± 3 in the sham group (difference, -3; 95% CI, -10 to 3; p = 0.30). Compared to the sham group, there were more serious adverse events reported in the active treatment group (13 vs 6; p = 0.053). Clinically important arrhythmias were detected by Holter monitoring in 36 out of 70 (51%) in the active group versus 22 out of 76 (29%) in the sham group (p = 0.006).

CONCLUSIONS

Esophageal stimulation via a special feeding catheter did not improve nutritional adequacy and was associated with increase risk of harm in critically ill patients.

Gastrointestinal dysfunction in the critically ill: a systematic scoping review and research agenda proposed by the Section of Metabolism, Endocrinology and Nutrition of the European Society of Intensive Care Medicine

BACKGROUND

Gastrointestinal (GI) dysfunction is frequent in the critically ill but can be overlooked as a result of the lack of standardization of the diagnostic and therapeutic approaches. We aimed to develop a research agenda for GI dysfunction for future research. We systematically reviewed the current knowledge on a broad range of subtopics from a specific viewpoint of GI dysfunction, highlighting the remaining areas of uncertainty and suggesting future studies.

METHODS

This systematic scoping review and research agenda was conducted following successive steps: (1) identify clinically important subtopics within the field of GI function which warrant further research; (2) systematically review the literature for each subtopic using PubMed, CENTRAL and Cochrane Database of Systematic Reviews; (3) summarize evidence for each subtopic; (4) identify areas of uncertainty; (5) formulate and refine study proposals that address these subtopics; and (6) prioritize study proposals via sequential voting rounds.

RESULTS

Five major themes were identified: (1) monitoring, (2) associations between GI function and outcome, (3) GI function and nutrition, (4) management of GI dysfunction and (5) pathophysiological mechanisms. Searches on 17 subtopics were performed and evidence summarized. Several areas of uncertainty were identified, six of them needing consensus process. Study proposals ranked among the first ten included: prevention and management of diarrhoea; management of upper and lower feeding intolerance, including indications for post-pyloric feeding and opioid antagonists; acute gastrointestinal injury grading as a bedside tool; the role of intra-abdominal hypertension in the development and monitoring of GI dysfunction and in the development of non-occlusive mesenteric ischaemia; and the effect of proton pump inhibitors on the microbiome in critical illness.

CONCLUSIONS

Current evidence on GI dysfunction is scarce, partially due to the lack of precise definitions. The use of core sets of monitoring and outcomes are required to improve the consistency of future studies. We propose several areas for consensus process and outline future study projects.

Gut dysmotility in the ICU: diagnosis and therapeutic options

PURPOSE OF REVIEW

To provide a comprehensive update of diagnosis and treatment of gastrointestinal dysmotility in the critically ill, with a focus on work published in the last 5 years.

RECENT FINDINGS

Symptoms and clinical features consistent with upper and/or lower gastrointestinal dysmotility occur frequently. Although features of gastrointestinal dysmotility are strongly associated with adverse outcomes, these associations may be because of unmeasured confounders. The use of ultrasonography to identify upper gastrointestinal dysmotility appears promising. Both nonpharmacological and pharmacological approaches to treat gastrointestinal dysmotility have recently been evaluated. These approaches include modification of macronutrient content and administration of promotility drugs, stool softeners or laxatives. Although these approaches may reduce features of gastrointestinal dysmotility, none have translated to patient-centred benefit.

SUMMARY

'Off-label' metoclopramide and/or erythromycin administration are effective for upper gastrointestinal dysmotility but have adverse effects. Trials of alternative or novel promotility drugs have not demonstrated superiority over current pharmacotherapies. Prophylactic laxative regimens to prevent non-defecation have been infrequently studied and there is no recent evidence to further inform treatment of established pseudo-obstruction. Further trials of nonpharmacological and pharmacological therapies to treat upper and lower gastrointestinal dysmotility are required and challenges in designing such trials are explored.

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.

Compliance and Adherence to Enteral Nutrition Treatment in Adults: A Systematic Review

OBJECTIVE

To review the scientific literature that has verified and/or assessed compliance and adherence to enteral nutrition (EN) in adult patients.

METHOD

This study involved a critical analysis of articles retrieved from MEDLINE (PubMed), The Cochrane Library, Embase, Scopus and Web of Science using the terms "Treatment Adherence and Compliance" and "Enteral Nutrition", applying the filters "Comparative Study" or "Clinical Trial", "Humans" and "Adults". Date of the search: 25 October 2018.

RESULTS

A total of 512 references were retrieved, of which 23 documents were selected after applying the inclusion and exclusion criteria. The techniques measuring adherence to EN were determined by dietary intake, self-reporting, counts of leftover containers or presence of complications; however, in no case were validated questionnaires used. The time and periodicity of the assessment presented very heterogeneous results, with measurement predominantly being done at the beginning and at the end of the study. The best adherence rates were obtained in hospitalized patients (approximately 80%).

CONCLUSIONS

Frequent and regular monitoring of the adherence of patients under prolonged treatment with EN is necessary, and the use of measurement techniques that allow obtaining information on the causes of non-adherence facilitates early interventions to optimize treatment outcomes. Patient and/or caregiver education in the management of EN and the intervention of the community pharmacy in monitoring patients can be key to improving the adherence to EN.

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.