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

Gastrointestinal Motility Disorders Correlate with Intracranial Bleeding, Opioid Use, and Brainstem Edema in Neurosurgical Patients

BACKGROUND

Gastrointestinal (GI) motility disorders may be directly associated with the intensity of acute brain injury, edema of the brainstem, and opioid use in neurosurgical patients.

METHODS

In this retrospective study, patient demographic characteristics, computed tomography (CT) scans, the occurrence of gastroparesis, constipation, and opioid use were registered during the intensive care unit (ICU) stay and correlated with days of mechanical ventilation, length of ICU stay, and survival. Gastroparesis was defined as residual gastric volume > 250 mL per day, and constipation was defined as the absence of stool for 3 days or more during the ICU stay.

RESULTS

Of 207 neurosurgical patients screened, 69 adult patients who spent more than 4 days in the ICU were included in the study. Gastroparesis was observed in 48 (69.6%) patients, constipation was observed in 67 (97.1%) patients, and stress ulcers were observed in 4 (5.8%) patients. Patients with brainstem edema (n = 57, 82.6%) had the first stool evacuation later compared with patients with no edema (8 [interquartile range (IQR) 5.25-9.75] vs. 3.5 [IQR 2.25-4] days; P < 0.001). In the logistic regression analysis, factors that were associated with GI dysmotility were central nervous system (CNS) bleeding (odds ratio [OR] 5.1, 95% confidence interval [CI] 1.26-20.8, P = 0.02), opioid use > 19.3 morphine equivalents (ME) per day (OR 5.37, 95% CI 1.1-27.1, P = 0.04), and brainstem edema (OR 4.9, 95% CI 1.1-21.6, P = 0.04). A receiver operating characteristic curve analysis confirmed that the cutoff value of > 6.78 ME per day was a good predictor determining GI dysmotility, with 89.5% sensitivity and 72.7% specificity (95% CI 0.67-0.88, area under the curve 0.784, Youden index 0.62, P = 0.001). Poor survival correlated with lower Glasgow Coma Score values (ρ =  - 520, P < 0.001), CNS bleeding (ρ = 0.393, P < 0.001), associated cardiac diseases (ρ = 0.279, P < 0.001), and cardiorespiratory arrest on admission (ρ = 0.315, P < 0.001), but not with GI dysmotility (ρ = 0.175, P = 0.402).

CONCLUSIONS

Significant correlation was registered between brainstem edema, gastrointestinal dysmotility, and opioids. CNS bleeding was the most important single factor influencing GI dysmotility. Further studies with opioid and nonopioid sedation may distinguish the influence of acute brain lesions versus drugs on GI dysmotility.

[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.

Constipation Caused by Anti-calcitonin Gene-Related Peptide Migraine Therapeutics Explained by Antagonism of Calcitonin Gene-Related Peptide's Motor-Stimulating and Prosecretory Function in the Intestine

The development of small-molecule calcitonin gene-related peptide (CGRP) receptor antagonists (gepants) and of monoclonal antibodies targeting the CGRP system has been a major advance in the management of migraine. In the randomized controlled trials before regulatory approval, the safety of these anti-CGRP migraine therapeutics was considered favorable and to stay within the expected profile. Post-approval real-world surveys reveal, however, constipation to be a major adverse event which may affect more than 50% of patients treated with erenumab (an antibody targeting the CGRP receptor), fremanezumab or galcanezumab (antibodies targeting CGRP). In this review article we address the question whether constipation caused by inhibition of CGRP signaling can be mechanistically deduced from the known pharmacological actions and pathophysiological implications of CGRP in the digestive tract. CGRP in the gut is expressed by two distinct neuronal populations: extrinsic primary afferent nerve fibers and distinct neurons of the intrinsic enteric nervous system. In particular, CGRP is a major messenger of enteric sensory neurons which in response to mucosal stimulation activate both ascending excitatory and descending inhibitory neuronal pathways that enable propulsive (peristaltic) motor activity to take place. In addition, CGRP is able to stimulate ion and water secretion into the intestinal lumen. The motor-stimulating and prosecretory actions of CGRP combine in accelerating intestinal transit, an activity profile that has been confirmed by the ability of CGRP to induce diarrhea in mice, dogs and humans. We therefore conclude that the constipation elicited by antibodies targeting CGRP or its receptor results from interference with the physiological function of CGRP in the small and large intestine in which it contributes to the maintenance of peristaltic motor activity, ion and water secretion and intestinal transit.

Association of Gastric Antrum Echodensity and Acute Gastrointestinal Injury in Critically Ill Patients

(1) Background: Acute muscle inflammation leads to increased sonographic echodensity. We developed a technique to characterize the echodensity of the gastric antrum wall and assess its feasibility in evaluating the severity of acute gastrointestinal injury (AGI); (2) Methods: The B-mode images of the gastric antrum of each enrolled patient were obtained daily by point-of-care ultrasound (POCUS). The 50th percentile, 85th percentile, and mean value of the grayscale distribution according to histogram analysis (ED50, ED85, and EDmean, respectively) were used to characterize the gastric antrum echodensity. Consistency and correlation analyses were performed to evaluate the feasibility and reproducibility of gastric antrum echodensity measurement. The association of gastric antrum echodensity with the severity of AGI and its ability to predict feeding intolerance (FI) were analyzed; (3) Results: In total, 206 POCUS images of 43 patients were analyzed. The gastric antrum echodensity measurements had sufficient intra- and inter-investigator reliabilities (intraclass correlation coefficient >0.9 for all parameters). The ED50 showed a significant upward trend as AGI severity increased, as well as ED85 and EDmean (p for trend <0.001, respectively). Patients who experienced FI had a higher ED50 (67.8 vs. 56.1, p = 0.02), ED85 (85.6 vs. 71.2, p = 0.01), and EDmean (70.3 vs. 57.6, p = 0.01) upon enteral feeding initiation; (4) Conclusions: Measurement of gastric antrum echodensity was technically feasible and reproducible in ventilated patients. Increased gastric antrum echodensity was associated with greater severity of AGI. Patients with higher gastric antrum echodensity upon enteral nutrition initiation via a nasogastric tube were more likely to develop FI.

Intestinal fatty acid-binding protein is a biomarker for diagnosis of biliary tract infection

Background and Aim

Biliary tract infection (BTI) is an inflammatory disease and commonly associated with bacteremia. Delays in diagnosis or treatment of BTI cause high morbidity and mortality. However, an early diagnosis depends on appropriate clinical investigations. Appropriate biomarkers are urgently needed to improve the BTI diagnostic rate. We hypothesized that intestinal fatty acid‐binding protein (I‐FABP) might be a potential biomarker for BTI diagnosis.

Methods

We examined data from subjects aged ≥18 years diagnosed with BTI, including cholangitis and cholecystitis, whose blood samples were adequate for I‐FABP and zonulin assessment. We also collected blood samples from healthy volunteers as the control group. We excluded subjects in both groups who received steroids, antibiotics, or probiotics within 1 month before hospital admission (BTI cohort) or participation in this research (controls). The main study endpoint was to compare the diagnostic ability of I‐FABP to detect BTI in comparison with high‐sensitivity C‐reactive protein (hs‐CRP) and zonulin.

Results

The study collected the data of 51 patients with BTI and 35 healthy subjects. The receiver operating characteristic (ROC) area under the curve (AUC) for I‐FABP was 0.884 (95% confidence interval [CI]: 0.814–0.954), numerically higher than that for hs‐CRP (0.880; 0.785–0.976) and zonulin (0.570; 0.444–0.697). We estimated that the optimal cutoff value of I‐FABP was 2.1 ng/mL (sensitivity: 0.804; specificity: 0.829) for the diagnosis of BTI.

Conclusions

In summary, this study suggests that I‐FABP may be a potential alternative biomarker to hs‐CRP for diagnosing BTI. Further research should verify the use of I‐FABP as a marker for BTI diagnosis, but also for other inflammatory diseases.

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.

Interstitial cells of Cajal are diminished in critically ill patients: Autopsy cases

OBJECTIVE

Gastrointestinal dysmotility in critically ill patients is important as enteral nutrition is crucial. However, normal gut motility is impaired under conditions of critical illness subsequent to severe insult. Interstitial cells of Cajal (ICC) form an extensive network associated with the myenteric plexus in the enteric nervous system. There are few reports about ICC distribution in critically ill patients. The aim of this study was to evaluate ICC in critically ill patients.

METHODS

Postmortem colon harvest was obtained from critically ill patients. Control specimens were obtained from patients without bowel movement problems who underwent hemicolectomy. The tissues were stained with c-Kit for ICC. The number of ICC was identified by counting from 10 high-power fields (HPFs).

RESULTS

Specimens from six patients were analyzed and compared with those from six control patients. All patients had abnormalities of crypt architecture and inflammatory cell infiltrations. Mucosal thickness tended to be lower in the critically ill patients than in the controls (147 ± 47 versus 231 ± 127 μm; P = 0.15). Muscle layer thickness tended to be higher in the critically ill patients than in the controls (494 ± 163 versus 394 ± 258 μm; P = 0.44). ICC in the critically ill patients were almost depleted in the colon compared with those in the controls. Significantly fewer ICC were present in the critically ill patients than in the controls (0.45 versus 7.25 cells/HPF; P < 0.05).

CONCLUSIONS

Critical illness is associated with diminished numbers of ICC in the colon. This finding could have implications for dysmotility in critically ill patients.

Electromagnetically guided bedside placement of post-pyloric feeding tubes in critical care

Post-pyloric feeding is recommended in critically ill patients with gastro-intestinal intolerance. However, traditional placement methods are logistically difficult and carry potential risks. The authors retrospectively compared the position of post-pyloric feeding tubes (PPFTs) using an electromagnetic device that demonstrated by X-ray and analysed the complication rates, proportion of lung placements avoided and the time taken to establish enteral feeding. Forty placements in 37 mechanically ventilated patients were analysed; there was a success rate of 87.5%. Sensitivity and specificity were 77% (95% CI 59.9-89.6%) and 100% (95% CI 48.0-100%). Five lung placements were identified in real time and therefore avoided. The mean (SD) time from PPFT placement to X-ray was 134 minutes (± 139 minutes) and, to feeding, 276 minutes (± 213 minutes). In conclusion, placement of PPFT using an electromagnetic device carries a high success rate, is safe and feasible to undertake at the bedside in mechanically ventilated patients.

Design, Formulation and In Vitro Evaluation of Sustained-release Tablet Formulations of Levosulpiride

OBJECTIVES

Levosulpiride is a widely used gastroprokinetic agent in the treatment of various gastric disorders; however, its short half-life and increased dosage frequency leads to non-compliance and possible adverse effects. The prime objective of the current study was to develop a sustained-release formulation of Levosulpiride incorporating bioresorbable cellulose derivatives.

MATERIALS AND METHODS

Sustained-release formulations of Levosulpiride were prepared through direct compression using various cellulose derivatives such as CMC sodium, HPC, and HPMC in different polymer-to-drug weight ratios as release-modifying polymers. The powder blends and compressed tablets were then subjected to pre-compressional and post-compressional evaluation, as well as FTIR analysis. In vitro release studies were performed for all formulations of the model drug in buffer solution of pH 6.8 at a wave length of 214 nm by a UV-visible light spectrophotometer.

RESULTS

The FTIR results confirmed that the interaction between components was physical, and from the different kinetic models data, the release profile was best expressed by the Higuchi model because the results showed high linearity. The results also showed formulation F9 to be the ideal one among the developed formulations, exhibiting sustained- release behavior.

CONCLUSION

Levosulpiride sustained-release matrices were prepared successfully using CMC sodium, HPC, and HPMC as the release-retarding polymer/carrier.

Constipation in critical care patients: both timing and duration matter

OBJECTIVE

Most of the studies have defined constipation as a period without stool after ICU admission. We aimed to test the impact of both duration and timing of infrequent defecation in critical care patients.

PATIENTS AND METHODS

We performed a prospective, bi-center, observational study. Patients were divided into three subgroups: 'not constipated', '3-5 days', and 'at least 6 days' (longest period without stool passage, respectively, shorter than 3 days, 3-5 days, and ≥6 days). Furthermore, 'early' constipated patients were defined as those for whom the longest time to stool passage occurred just after ICU admission, whereas for 'late' constipated patients the longest period without stool occurred later during ICU stay.

RESULTS

A total of 182 patients were included: the mean age was 67.2 years (54.4-78.9 years), 80 were women, and simplified acute physiology score II was 42 (34-52). In all, 42 (23.1%), 82 (45.1%), and 58 (31.8%) belonged to the nonconstipated, 3-5 days, or greater than or equal to 6 days subgroup of patients, respectively. Time spent under mechanical ventilation and ICU length of stay was longer in the greater than or equal to 6 days subgroups as compared with both other subgroups. ICU stay was longer in the 3-5 days subgroup as compared with the not constipated patients. Furthermore, the late patients of the greater than or equal to 6 days subgroups exhibited worse survival as compared with all other patients.

CONCLUSION

Both timing and duration of infrequent defecation seem to have an impact on critical care patient's outcome, and should therefore be included in the diagnostic criteria.

Gut-origin sepsis in the critically ill patient: pathophysiology and treatment

INTRODUCTION

Gut permeability is increased in critically ill patients, and associated with the development of the systemic inflammatory response syndrome and multiple organ dysfunction syndrome (MODS). The pathogenetic link(s) and potential therapies are an area of intense research over the last decades.

METHODS

We thoroughly reviewed the literature on gut-origin sepsis and MODS in critically ill patients, with emphasis on the implicated pathophysiological mechanisms and therapeutic interventions.

FINDINGS

Intestinal barrier failure leading to systemic bacterial translocation associated with MODS was the predominant pathophysiological theory for several years. However, clinical studies with critically ill patients failed to provide the evidence of systemic spread of gut-derived bacteria and/or their products as a cause of MODS. Newer experimental data highlight the role of the mesenteric lymph as a carrier of gut-derived danger-associated molecular patterns (DAMPs) to the lung and the systemic circulation. These substances are recognized by pattern recognition receptor-bearing cells in diverse tissues and promote proinflammatory pathways and the development MODS. Therefore, the gut becomes a pivotal proinflammatory organ, driving the systemic inflammatory response through DAMPs release in mesenteric lymph, without the need for systemic bacterial translocation.

CONCLUSIONS

There is an emerging need for application of sensitive non-invasive and easily measured biomarkers of early intestinal injury (e.g., citrulline, intestinal fatty acid protein, and zonulin) in our everyday clinical practice, guiding the early pharmacological intervention in critically ill patients to restore or prevent intestinal injury and improve their outcomes.

Evaluation of gastric motility through surface electrogastrography in critically ill septic patients. Comparison of metoclopramide and domperidone effects: A pilot randomized clinical trial

INTRODUCTION AND AIMS

Critically ill patients present with a broad spectrum of gastrointestinal motility disorders that affect the digestive tract. Our aim was to compare the effect of two prokinetic drugs on gastric electrical rhythm in critically ill septic patients, measured through surface electrogastrography (EGG).

MATERIAL AND METHODS

A prospective triple-blinded randomized study was conducted on 36 patients admitted to the intensive care unit (ICU) with the diagnosis of septic shock. They were randomized to receive metoclopramide or domperidone. We assessed dominant frequency (DF), percentage distribution over time, and dominant power (DP), which represents the strength of contraction, before and after administration of the study drugs.

RESULTS

Reliable electrogastrograms were achieved in all patients. In relation to the distribution of DF over time, 64% of patients had dysrhythmia, the mean baseline DF was 2.9 cpm, and the mean DP was 56.5μv After drug administration, 58% of the patients had dysrhythmia, the mean DF increased to 5.7 cpm (P<.05), and the DP did not change (57.4μv²). There were no significant differences between drugs. In the metoclopramide group, the baseline DF was 2.1 cpm and the baseline DP was 26.1μv². The post-drug values increased to 5.4 cpm and 34.1μv², respectively. In the domperidone group, the baseline DF was 3.7 cpm and the baseline DP was 86.9μv². After drug administration, the DF increased to 6.1 cpm and the DP decreased to 83.5μv².

CONCLUSIONS

Both metoclopramide and domperidone similarly increased the DF of gastric pacemaker activity and improved gastric motility by restoring a normogastric pattern. Gastric dysmotility is frequent in septic patients.

Effects of Rhubarb on Intestinal Dysmotility in Critically Ill Patients

Intestinal dysmotility is a major problem in critically ill patients. This report describes the successful treatment of intestinal dysmotility with rhubarb as a laxative in six critically ill patients on mechanical ventilation. Bowel movement and defecation occurred in all patients an average of 1.8 days after the administration of powdered rhubarb. In 4 patients who also had gastric reflux, the reflux volume via nasal tube was decreased an average of 3.5 days after the initiation of rhubarb treatment, and enteral nutrition was able to be started. Rhubarb may be useful for the treatment of incompetent gastric and intestinal motility in critically ill 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.

Gastrointestinal motility dysfunction in critically ill patients: Pathogenesis, clinical assessment, and treatment

Gastrointestinal motility dysfunction is a common clinical complication in ICU patients, which can lead to difficulty in enteral nutrition, vomiting, diarrhea, increased intra-abdominal pressure, ventilator associated pneumonia, intestinal flora displacement, and other adverse reactions. The clinical features of gastrointestinal dysfunction mainly include gastric emptying disturbance, intestinal dysfunction, and gastrointestinal motility disorders. The causes of gastrointestinal motility dysfunction in ICU patients are complex and the clinical evaluation of gastrointestinal dysfunction is difficult. These factors have led to the fact that gastrointestinal motility monitoring techniques have not been widely used in clinical practice. Timely detection and correction of gastrointestinal motility dysfunction in ICU patients can improve outcomes. This article reviews the etiology, clinical evaluation, and treatment of gastrointestinal motility dysfunction in ICU patients.

Electroacupuncture Improves Gastric Emptying in Critically Ill Neurosurgical Patients: A Pilot Study

Objective

To compare the efficacy of combined electroacupuncture and metoclopramide treatment with that of metoclopramide only in improving gastric emptying in critically ill neurosurgical patients.

Methods

In this prospective case-control pilot study, a total of 16 adult critically ill mechanically ventilated patients who were treated in the surgical intensive care unit were enrolled. Electrical stimulation was applied to 4 pairs of points (maximum intensity < 9.8 mA at 2 Hz). Patients in the control group received standard treatment with intravenous metoclopramide only. Patients in the experimental group received intravenous metoclopramide plus electroacupuncture treatment once daily for 6 consecutive days.

Results

Gastric residual volume in the experimental group (n = 7) reduced gradually until the fourth day after treatment with electroacupuncture combined with routine metoclopramide administration. Beginning on the fourth day, residual volume was maintained at less than 200 ml per day for the following two days. In the control group (n = 9), there was a gradual reduction in residual volume during the first four days followed by a rebounding increase over the next two days.

Conclusions

Electroacupuncture combined with intravenous metoclopramide is a more effective treatment for gastric emptying than metoclopramide alone in adult critically ill patients with impaired brain function.

Effect of Intravenous Fluids and Analgesia on Dysmotility in Patients With Acute Pancreatitis: A Prospective Cohort Study

OBJECTIVES

Analgesia and intravenous fluid resuscitation are cornerstones of initial patient management in acute pancreatitis (AP). The aim was to investigate the effect of intravenous fluids and analgesia on gastrointestinal motility in the early course of AP.

METHODS

Gastrointestinal dysmotility was assessed using the Gastroparesis Cardinal Symptom Index (GCSI). One-way analysis of variance and analysis of covariance were conducted, adjusting for age, sex, body mass index, severity of AP, preexisting diabetes mellitus, and time from first symptom onset to hospital admission.

RESULTS

A total of 108 patients with AP were prospectively enrolled. Opioid analgesia, when compared with nonopioid analgesia, was significantly associated with increase in total GCSI score in both unadjusted and adjusted analyses. There was no significant difference between aggressive and nonaggressive fluid resuscitation in both unadjusted and adjusted analyses. A combination of opioids and any intravenous fluids was associated with a significantly increased total GCSI score compared with opioids and no intravenous fluids in both unadjusted and adjusted analyses. Duration of symptoms was the confounder that significantly affected 6 of 9 studied associations.

CONCLUSIONS

Intravenous fluids and analgesia significantly affect motility independent of severity and other covariates. Guidelines on prudent use of opioids and fluids in AP need to be developed, particularly taking into account duration of symptoms from onset to hospitalization.

Effects of Synbiotic2000™ Forte on the Intestinal Motility and Interstitial Cells of Cajal in TBI Mouse Model

The main objective of this study was to investigate the effects of Synbiotic2000™ Forte on the intestinal motility and interstitial cells of Cajal (ICC) in traumatic brain injury (TBI) mouse model. Kunming mice were randomly divided into sham operation group (S group), enteral nutrition group with TBI (E group), and Synbiotic2000™ Forte group with TBI (P group). The contractile activity of the intestinal smooth muscle, densities and ultrastructure of the ICC, kit protein concentration, weight, and defecation of mice were monitored and analyzed. TBI markedly suppressed contractile activity of the intestinal smooth muscle (P < 0.01), which led to a reduction of defecation (P < 0.01) and weight (P < 0.01). However, application of Synbiotic2000™ Forte significantly improved contractile activity of the small intestine (P < 0.01), which may be related to protective effects to the interstitial cells of Cajal, smooth muscle cells, and enteric neurons. TBI impaired ICC networks and densities (P < 0.01), events that were protected by the application of Synbiotic2000™ Forte. Synbiotic2000™ Forte may attenuate TBI-mediated inhibition of the kit protein pathway. Synbiotic2000™ Forte may improve intestinal motility and protect the ICC in the TBI mouse. These findings provide a novel support for the application of Synbiotic2000™ Forte in intestinal motility disturbance after TBI.

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.

Constipation incidence and impact in medical critical care patients: importance of the definition criterion

BACKGROUND

Constipation incidence and impact remain controversial in the ICU. This may depend on the definition criterion used in the previous studies on the field. We aimed to determine the frequency and significance of constipation according to its definition criterion.

METHODS

This is a prospective observational study. Adult patients without a cause of transit time modification and laxative intake within the first 3 days were screened. Constipation was defined by a first stool passage occurring after 3 days of ICU stay. Thereafter, we identified two subgroups of patients: absence of stool passage more than 3 days but less than 6 days (3-day subgroup), and no stool passage for 6 days or more (6-day subgroup). Survival, length of stay and time spent under mechanical ventilation (MV) were compared according to constipation status.

RESULTS

Among 189 included patients [age 60.8 (49.5-74.2) years, SAPS II 44 (34-53)], 98 (51.9%) exhibited constipation (3-day subgroup n=53, 6-day subgroup n=45). Constipated patients were more likely to receive MV, sedation, vasopressors, enteral nutrition and neuromuscular blocking agents. ICU length of stay and time spent under MV was longer in the 6-day subgroup but not in the 3-day subgroup of patients.

CONCLUSION

With regard to outcomes, defining constipation by the absence of stool passage less than 6 days after ICU admission does not identify a specific subset of population. Further studies on the management of this condition should focus on these 'long-term' constipated patients.

Gut Motility Issues in Critical Illness

Acute gastrointestinal injury (AGI) is common in critical illness and negatively affects outcome. A variety of definitions have been used to describe AGI, which has led to clinical confusion and hampered comparison of research studies across institutions. An international working group of the European Society of Intensive Care Medicine was convened to standardize definitions for AGI and provide current evidence-based understanding of its pathophysiology and management. This disorder is associated with a wide variety of signs and symptoms and may be difficult to detect, therefore a high index of suspicion is warranted.

Interventions That Affect Gastrointestinal Motility in Hospitalized Adult Patients: A Systematic Review and Meta-Analysis of Double-Blind Placebo-Controlled Randomized Trials

Gastrointestinal (GI) dysmotility is a common complication in acute, critically ill, postoperative, and chronic patients that may lead to impaired nutrient delivery, poor clinical, and patient-reported outcomes. Several pharmacological and nonpharmacological interventions to treat GI dysmotility were investigated in dozens of clinical studies. However, they often yielded conflicting results, at least in part, because various (nonstandardized) definitions of GI dysmotility were used and methodological quality of studies was poor. While a universally accepted definition of GI dysmotility is yet to be developed, a systematic analysis of data derived from double-blind placebo-controlled randomized trials may provide robust data on absolute and relative effectiveness of various interventions as the study outcome (GI motility) was assessed in the least biased manner.To systematically review data from double-blind placebo-controlled randomized trials to determine and compare the effectiveness of interventions that affect GI motility.Three electronic databases (MEDLINE, SCOPUS, and EMBASE) were searched. A random effects model was used for meta-analysis. The summary estimates were reported as mean difference (MD) with the corresponding 95% confidence interval (CI).A total of 38 double-blind placebo-controlled randomized trials involving 2371 patients were eligible for inclusion in the systematic review. These studies investigated a total of 20 different interventions, of which 6 interventions were meta-analyzed. Of them, the use of dopamine receptor antagonists (MD, -8.99; 95% CI, -17.72 to -0.27; P = 0.04) and macrolides (MD, -26.04; 95% CI, -51.25 to -0.82; P = 0.04) significantly improved GI motility compared with the placebo group. The use of botulism toxin significantly impaired GI motility compared with the placebo group (MD, 5.31; 95% CI, -0.04 to 10.67; P = 0.05). Other interventions (dietary factors, probiotics, hormones) did not affect GI motility.Based on the best available data and taking into account the safety profile of each class of intervention, dopamine receptor antagonists and macrolides significantly improve GI motility and are medications of choice in treating GI dysmotility.

Microbial cell preparation in enteral feeding in critically ill patients: A randomized, double-blind, placebo-controlled clinical trial

Gut failure is a common condition in critically ill patients in the intensive care unit (ICU). Enteral feeding is usually the first line of choice for nutrition support in critically ill patients. However, enteral feeding has its own set of complications such as alterations in gut transit time and composition of gut eco-culture. The primary aim of this study was to investigate the effect of microbial cell preparation on the return of gut function, white blood cell count, C-reactive protein levels, number of days on mechanical ventilation, and length of stay in ICU. A consecutive cohort of 60 patients admitted to the ICU in University Malaya Medical Centre requiring enteral feeding were prospectively randomized to receive either treatment (n = 30) or placebo (n = 30). Patients receiving enteral feeding supplemented with a course of treatment achieved a faster return of gut function and required shorter duration of mechanical ventilation and shorter length of stay in the ICU. However, inflammatory markers did not show any significant change in the pretreatment and posttreatment groups. Overall, it can be concluded that microbial cell preparation enhances gut function and the overall clinical outcome of critically ill patients receiving enteral feeding in the ICU.

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.

Small intestinal smooth muscle cell apoptosis in rats with severe acute pancreatitis

AIM: To investigate whether small intestinal smooth muscle cell apoptosis occurs in rats with severe acute pancreatitis (SAP) and the underlying mechanism.

METHODS: Male SD rats were randomly divided into a sham operation group (SO) and an SAP group. SAP was induced by injecting 3.8% sodium taurocholate solution into the subcapsular region of the pancreas of SD rats. Rats in the SO group were injected with 1 mL/kg normal saline. Forty-eight hours later, pancreatic pathological changes and the transit rate of the small bowel were determined. Cell apoptosis, expression of adenine nucleotide translocator (ANT) mRNA, mitochondrial membrane potential, and cytochrome C (Cyt-C) protein expression in the small intestinal smooth muscle were determined by TUNEL method, RT-PCR, flow cytometry and immunohistochemistry, respectively.

RESULTS: Compared with rats in the SO group, rats in the SAP group developed typical SAP symptoms, with a higher pancreatic pathology score (6.85 ± 1.21 vs 1.13 ± 0.91, P < 0.001). Compared with rats in the SO group, the transit rate of the small intestine was significantly lower (55.91% ± 2.93% vs 68.9% ± 5.69%, P < 0.05), the apoptosis of smooth muscle cells in the small intestine increased significantly (0.056 ± 0.184 vs 0.029 ± 0.038, P < 0.05), the expression of ANT mRNA and Cyt-C protein (0.024 ± 0.001 vs 0.057 ± 0.168, P < 0.001) in the smooth muscle of the small intestine increased significantly, and the mitochondrial membrane potential decreased significantly (5.07 ± 0.92 vs 2.40 ± 0.50, P < 0.05) in the SAP group.

CONCLUSION: The mitochondrial signal transduction pathway contributes to smooth muscle cell apoptosis in the small intestine, which may play a role in small intestinal motility dysfunction in SAP rats.

Enhanced protein-energy provision via the enteral route feeding protocol in critically ill patients: results of a cluster randomized trial

OBJECTIVES

To determine the effect of the enhanced protein-energy provision via the enteral route feeding protocol, combined with a nursing educational intervention on nutritional intake, compared to usual care.

DESIGN

Prospective, cluster randomized trial.

SETTING

Eighteen ICUs from United States and Canada with low baseline nutritional adequacy.

PATIENTS

One thousand fifty-nine mechanically ventilated, critically ill patients.

INTERVENTIONS

A novel feeding protocol combined with a nursing educational intervention.

MEASUREMENTS AND MAIN RESULTS

The two primary efficacy outcomes were the proportion of the protein and energy prescriptions received by study patients via the enteral route over the first 12 days in the ICU. Safety outcomes were the prevalence of vomiting, witnessed aspiration, and ICU-acquired pneumonia. The proportion of prescribed protein and energy delivered by enteral nutrition was greater in the intervention sites compared to the control sites. Adjusted absolute mean difference between groups in the protein and energy increases were 14% (95% CI, 5-23%; p = 0.005) and 12% (95% CI, 5-20%; p = 0.004), respectively. The intervention sites had a similar improvement in protein and calories when appropriate parenteral nutrition was added to enteral sources. Use of the enhanced protein-energy provision via the enteral route feeding protocol was associated with a decrease in the average time from ICU admission to start of enteral nutrition compared to the control group (40.7-29.7 hr vs 33.6-35.2 hr, p = 0.10). Complication rates were no different between the two groups.

CONCLUSIONS

In ICUs with low baseline nutritional adequacy, use of the enhanced protein-energy provision via the enteral route feeding protocol is safe and results in modest but statistically significant increases in protein and calorie intake.

Commonly used gastrointestinal drugs

This chapter reviews the spectrum and mechanisms of neurologic adverse effects of commonly used gastrointestinal drugs including antiemetics, promotility drugs, laxatives, antimotility drugs, and drugs for acid-related disorders. The commonly used gastrointestinal drugs as a group are considered safe and are widely used. A range of neurologic complications are reported following use of various gastrointestinal drugs. Acute neurotoxicities, including transient akathisias, oculogyric crisis, delirium, seizures, and strokes, can develop after use of certain gastrointestinal medications, while disabling and pervasive tardive syndromes are described following long-term and often unsupervised use of phenothiazines, metoclopramide, and other drugs. In rare instances, some of the antiemetics can precipitate life-threatening extrapyramidal reactions, neuroleptic malignant syndrome, or serotonin syndrome. In contrast, concerns about the cardiovascular toxicity of drugs such as cisapride and tegaserod have been grave enough to lead to their withdrawal from many world markets. Awareness and recognition of the neurotoxicity of gastrointestinal drugs is essential to help weigh the benefit of their use against possible adverse effects, even if uncommon. Furthermore, as far as possible, drugs such as metoclopramide and others that can lead to tardive dyskinesias should be used for as short time as possible, with close clinical monitoring and patient education.

Severe acute pancreatitis complicated with gastrointestinal dysfunction: Pathogenesis, diagnosis and treatment

Severe acute pancreatitis (SAP) is often associated with gastrointestinal dysfunction, leading to gastrointestinal motility disorders and even gastrointestinal failure, which has an important effect on SAP progression and prognosis, directly influences the outcome of treatment, is an important cause of death in patients with SAP, and moreover, has been one of the important prognostic factors for SAP. This review aims to discuss the pathophysiology, pathogenesis, diagnosis and treatment of SAP with gastrointestinal dysfunction.

Review article: the assessment and management of chronic severe gastrointestinal dysmotility in adults

BACKGROUND

The characterisation and management of chronic severe gastrointestinal (GI) dysmotility are challenging. It may cause intestinal failure requiring home parenteral nutrition (HPN).

AIMS

To review the presentation, aetiology, characterisation, management and outcome of chronic severe GI dysmotility, and to suggest a pragmatic management algorithm.

METHODS

PubMed search was performed up to December 2012 using appropriate search terms, restricted to human articles and reviewed for relevance. Segmental dysmotility, acute ileus, functional syndromes and non-English articles were excluded. Evidence and recommendations were evaluated using the GRADE system.

RESULTS

In total, 721 relevant articles were reviewed. A coherent and definitive picture is hampered by overlapping classification systems using multi-modal characterisation methods, subject to pitfalls and some requiring further validation. The literature is confined to case series with no randomised trials. Fewer than 20% undergo full thickness jejunal biopsy, which are otherwise labelled idiopathic. However, in studies with up to 80% biopsy rates, neuromuscular abnormalities may be found in 90%. Between 14% and 50% will require HPN, comprising 8-14% of all HPN patients, of which 2/3 are primary/idiopathic and 1/3 secondary, with scleroderma being the leading secondary cause. Ten-year  mortality ranges from 13% to 35% and is worst in elderly scleroderma patients. Management includes limited treatments for secondary causes, prokinetics, symptom palliation, psychological support, nutrition, hydration and judicious surgery.

CONCLUSIONS

Severe dysmotility often remains idiopathic. It is rarely possible to alter disease trajectory; consequently, prognosis may be poor. Multi-disciplinary teams in a specialist setting can improve outcomes. Graded recommendations are enumerated and a pragmatic algorithm is suggested.

Predictive significance of serum levels of gastrointestinal hormones and cytokines for disease progression in patients with rotavirus diarrhea

AIM: To assess the early predictive value of serum levels of gastrointestinal hormones and cytokines in patients with rotavirus diarrhea.

METHODS: Serum levels of 5-serotonin, vasoactive intestinal peptide (VIP), gastrin (GAS), motilin (MOT) and cytokines (endothelin, IL-10) were determined by enzyme-linked immunosorbent assay (ELISA) in 65 children with severe, moderate or mild rotavirus infection during acute or convalescent phase and 60 normal healthy children.

RESULTS: Serum levels of 5-serotonin, VIP, GAS, MOT, and endothelin were significantly higher and that of IL-10 was significantly lower in children with rotavirus infection during the acute phase than in normal control controls (all P < 0.05). Serum levels of 5-HT, VIP, MOT, and endothelin were significantly higher in patients with severe rotavirus infection than in those with moderate or mild rotavirus infection (all P < 0.05). Serum levels of GAS and IL-10 showed no significant difference between patients with moderate rotavirus infection and those with mild disease (P > 0.05). Serum levels of 5-serotonin, VIP, endothelin and IL-10 were significantly higher in patients with acute phase rotavirus infection having diarrhea >3 d than in those having diarrhea <3 d (all P < 0.05), while GAS and MOT levels were not statistically significant between the two groups (both P > 0.05).

CONCLUSION: Pathophysiological changes in rotavirus diarrhea may be associated with the changes in serum levels of gastrointestinal hormones and cytokines. The relevant gastrointestinal hormones and cytokines may be used to predict rotavirus disease progression.

Impaired gastrointestinal transit and its associated morbidity in the intensive care unit

PURPOSE

To determine the proportion of critically ill adults developing impaired gastrointestinal transit (IGT) using a clinically pragmatic definition, its associated morbidity and risk factors.

MATERIALS AND METHODS

Critically ill adult patients receiving enteral nutrition for ≥ 72 hours and mechanically ventilated for ≥ 48 hours were prospectively identified. IGT was defined as absence of a bowel movement for ≥ 3 days, treatment for constipation, and one of the following: (1) radiologic confirmed ileus, (2) feed intolerance, (3) abdominal distention, or (4) gastric decompression.

RESULTS

One thousand patients were screened, and 248 were included for analysis. Fifty patients (20.1%; 95% confidence interval, 15.1-25.6%) developed IGT persisting for 6.5 ± 2.5 days. Patients with IGT had longer lengths of intensive care unit stay and were less likely to reach nutrition targets compared to patients without IGT or traditional definitions of constipation. Daily opioid use and pharmacological constipation prophylaxis were identified risk factors for IGT.

CONCLUSION

Traditional definitions of constipation or ileus in intensive care unit patients are simplistic and lack clinical relevance. Pragmatically defined IGT is a common complication of critical illness and is associated with significant morbidity. Future interventional studies for IGT in critically ill adults should use a more clinically relevant definition and evaluate energy deficits and lengths of stay as clinically relevant outcomes.

Probiotic/synbiotic therapy for treating critically ill patients from a gut microbiota perspective

The gut is an important target organ for stress caused by severe insults such as sepsis, trauma, burn, shock, bleeding and infection. Severe insult to the gut is considered to have an important role in promoting infectious complications and multiple organ dysfunction syndrome. These are sequelae of interactions between deteriorated intestinal epithelium, the immune system and commensal bacteria. The gut is the "motor" of multiple organ failure, and now it is recognized that gut dysfunction is a causative factor in disease progression. The gut flora and environment are significantly altered in critically ill patients, and the number of obligate anaerobes is associated with prognosis. Synbiotic therapy is a combination of probiotics and prebiotics. Probiotic, prebiotic and synbiotic treatment has been shown to be a promising therapy to maintain and repair the gut microbiota and gut environment. In the critically ill, such as major abdominal surgery, trauma and ICU patients, synbiotic therapy has been shown to significantly reduce septic complications. Further basic and clinical research would clarify the underlying mechanisms of the therapeutic effect of probiotic/synbiotic treatment and define the appropriate conditions for use.

Motility disorders of the upper gastrointestinal tract in the intensive care unit: pathophysiology and contemporary management

Upper gastrointestinal (GI) dysmotility, an entity commonly found in the intensive care unit setting, can lead to insufficient nutrient intake while increasing the risk of infection and mortality. Further, overcoming the altered motility with early enteral feeding is associated with a reduced incidence of infectious complications in intensive care unit patients. Upper GI dysmotility in critical care patients is a common occurrence, and there are many causes for this problem, which affects a very heterogenous population with a multitude of underlying medical abnormalities. Therefore, it is of utmost importance to identify this widespread problem and subsequently institute a proper therapy as rapidly as possible. Prokinetic pharmacotherapies are currently the mainstay for the management of disordered upper GI motility. Future therapies, aimed at the underlying pathophysiology of this complex problem, are under investigation. These aim is to reduce the side effects of the currently available options, while improving on nutrition delivery in the critically ill. This review discusses the pathophysiology, clinical manifestations, diagnosis, and treatment of upper GI motility disturbances in the critically ill.

Alternatives to prokinetics to move the pylorus and colon

PURPOSE OF REVIEW

Gastrointestinal motility disorders (GMDs) are common in the ICU. When encountering these problems, one typically thinks of prokinetics. This review summarizes current evidence of treatments.

RECENT FINDINGS

Prokinetics are not the first-line therapy for GMDs. In fact, the clinical implications of using prokinetic agents are rather controversial. Current evidence on alternative treatment modalities such as fluid and electrolyte management, laxatives, opioid antagonists, purgative enemas, acupuncture, physical therapies and probiotics is growing.

SUMMARY

Current state of the art to treat GMDs is primarily focused at the elimination of underlying trigger factors. Fluid and electrolyte management as well as laxatives and peripherally acting μ-opioid receptor antagonists are the recommended first-line therapies that can be complemented with prokinetics. Acupuncture as well as physical modalities, such as massage or warming of the abdomen, is promising with few side-effects and should be considered as well.

Gastrointestinal function in intensive care patients: terminology, definitions and management. Recommendations of the ESICM Working Group on Abdominal Problems

Purpose

Acute gastrointestinal (GI) dysfunction and failure have been increasingly recognized in critically ill patients. The variety of definitions proposed in the past has led to confusion and difficulty in comparing one study to another. An international working group convened to standardize the definitions for acute GI failure and GI symptoms and to review the therapeutic options.

Methods

The Working Group on Abdominal Problems (WGAP) of the European Society of Intensive Care Medicine (ESICM) developed the definitions for GI dysfunction in intensive care patients on the basis of the available evidence and current understanding of the pathophysiology.

Results

Definitions for acute gastrointestinal injury (AGI) with its four grades of severity, as well as for feeding intolerance syndrome and GI symptoms (e.g. vomiting, diarrhoea, paralysis, high gastric residual volumes) are proposed. AGI is a malfunctioning of the GI tract in intensive care patients due to their acute illness. AGI grade I = increased risk of developing GI dysfunction or failure (a self-limiting condition); AGI grade II = GI dysfunction (a condition that requires interventions); AGI grade III = GI failure (GI function cannot be restored with interventions); AGI grade IV = dramatically manifesting GI failure (a condition that is immediately life-threatening). Current evidence and expert opinions regarding treatment of acute GI dysfunction are provided.

Conclusions

State-of-the-art definitions for GI dysfunction with gradation as well as management recommendations are proposed on the basis of current medical evidence and expert opinion. The WGAP recommends using these definitions for clinical and research purposes.

Electronic supplementary material

The online version of this article (doi:10.1007/s00134-011-2459-y) contains supplementary material, which is available to authorized users.

Neostigmine in the treatment of refractory constipation in critically ill children

Constipation is a common complication in critically ill children and it is occasionally resistant to the drugs typically used in treatment. Neostigmine has been used in some cases of refractory constipation in critically ill adults. There is no reference to its use in critically ill children. We describe 3 cases of refractory constipation in critically ill children treated with intravenous neostigmine by continuous infusion. Two patients responded well. There were no adverse effects. We conclude that continuous intravenous neostigmine can be effective in critically ill children with refractory constipation. Further studies are necessary to determine the dose and safety of the treatment.

Enteral nutrition in patients with severe traumatic brain injury: reasons for intolerance and medical management

Approximately, 50% of patients with severe traumatic brain injury (TBI) exhibit intolerance to enteral nutrition (EN). This intolerance hampers the survival and rehabilitation of this subpopulation to a great extent, and poses various difficulties for clinicians due to its complex underlying mechanisms. This review discusses the possible reasons for intolerance to EN following severe TBI, current trends in medical management, as well as other related issues that are experienced by many clinicians.

Gastrointestinal dysmotility is associated with altered gut flora and septic mortality in patients with severe systemic inflammatory response syndrome: a preliminary study

BACKGROUND

The gut is an important target organ for injury after severe insult, and resolution of feeding intolerance is crucial for critically ill patients. We investigated gut flora and motility to evaluate the impact of gastrointestinal dysmotility on septic complications in patients with severe systemic inflammatory response syndrome (SIRS).

METHODS

Sixty-three ICU patients with severe SIRS were divided into two groups depending on their intestinal condition. Patients with feeding intolerance comprised patients who had feeding intolerance, defined as ≥ 300 mL reflux from nasal gastric feeding tube in 24 h, and patients without feeding intolerance comprised patients with no feeding intolerance. We compared fecal microflora, incidences of bacteremia, and mortality between these groups.

KEY RESULTS

Analysis of feces showed that patients with feeding intolerance had significantly lower numbers of total obligate anaerobes including Bacteroidaceae and Bifidobacterium, higher numbers of Staphylococcus, lower concentrations of acetic acid and propionic acid, and higher concentrations of succinic acid and lactic acid than those in patients without feeding intolerance (P ≤ 0.05). Patients with feeding intolerance had higher incidences of bacteremia (86%vs 18%) and mortality (64%vs 20%) than did patients without feeding intolerance (P ≤ 0.05).

CONCLUSIONS & INFERENCES

Gut flora and organic acids were significantly altered in patients with severe SIRS complicated by gastrointestinal dysmotility, which was associated with higher septic mortality in SIRS patients.

Identifying the factors that influence energy deficit in the adult intensive care unit: a mixed linear model analysis

BACKGROUND

Critically ill patients frequently receive inadequate nutrition support as a result of under- or overfeeding. Malnutrition in intensive care unit (ICU) patients is associated with increased morbidity and mortality. The present study aimed to identify the significant factors that influence energy deficit in the ICU.

METHODS

ICU patients with a length of stay of ≥3 days were studied for 30 days over two consecutive years at a large university teaching hospital. Fifty-six Patients were studied, with a total of 530 records of feeding days. Information was collected for: day when feed initiated, age, gender, length of stay, Acute Physiological and Chronic Health Evaluation score (APACHE II), fed within 24 h, speciality, type of ventilation, feeding route, outcome (survived/died), diarrhoea (yes/no), aspirate volume, dietitian observed nutritional status (malnourished/not), sedation, estimated energy requirements and energy received. Mixed linear models for longitudinal data were used with energy deficit (energy received - energy requirements) as the dependent variable.

RESULTS

Factors that were found to have a significant association with energy deficit were: day feeding was initiated (P<0.001), whether fed within 24 h (P<0.001) and whether sedated (P<0.001). Furthermore, three combined effects were found: ventilation mode and aspirate volume (P<0.007), fed within 24 h and ventilation mode (P<0.001), fed within 24 h and sedation (P<0.017).

CONCLUSIONS

The number of days after feeding was initiated, initiation of feeding within 24 h and sedation have been identified as factors that predict energy deficit during ICU stay. Efforts to initiate feeding as soon as possible and minimise interruptions to feeding may reduce energy deficits in these vulnerable patients.

Practicalities of nutrition support in the intensive care unit: the usefulness of gastric residual volume and prokinetic agents with enteral nutrition

The provision of early nutrition therapy to critically ill patients is established as the standard of care in most intensive care units around the world. Despite the known benefits, tolerance of enteral nutrition in the critically ill varies and delivery is often interrupted. Observational research has demonstrated that clinicians deliver little more than half of the enteral nutrition they plan to provide. The main clinical tool for assessing gastric tolerance is gastric residual volume; however, its usefulness in this setting is debated. There are several strategies employed to improve the tolerance and hence adequacy of enteral nutrition delivery in the critically ill. One of the most widely used strategies is that of prokinetic drug administration, most commonly metoclopramide and erythromycin. Although there are new agents being investigated, none are ready for routine application in the critically ill and the benefits are still being established. This review investigates current practice and considers the literature on assessment of enteral tolerance and optimization of enteral nutrition in the critically ill.

Potential benefits of pro- and prebiotics on intestinal mucosal immunity and intestinal barrier in short bowel syndrome

The mechanism of impaired gut barrier function in patients with short bowel syndrome (SBS) is poorly understood and includes decreased intestinal motility leading to bacterial overgrowth, a reduction in gut-associated lymphoid tissue following the loss of intestinal length, inhibition of mucosal immunity of the small intestine by intravenous total parental nutrition, and changes in intestinal permeability to macromolecules. Novel therapeutic strategies (i.e. nutritive and surgical) have been introduced in order to prevent the establishment or improve the outcome of this prevalent disease. Pre- and probiotics as a nutritive supplement are already known to be very active in the intestinal tract (mainly in the colon) by maintaining a healthy gut microflora and influencing metabolic, trophic and protective mechanisms, such as the production of SCFA which influence epithelial cell metabolism, turnover and apoptosis. Probiotics have been recommended for patients suffering from SBS in order to decrease bacterial overgrowth and prevent bacterial translocation, two major mechanisms in the pathogenesis of SBS. The present review discusses the research available in the international literature, clinical and experimental, regarding probiotic supplementation for this complicated group of patients based on the clinical spectrum and pathophysiological aspects of the syndrome. The clinical data that were collected for the purposes of the present review suggest that it is difficult to correctly characterise probiotics as a preventive or therapeutic measure. It is very challenging after all to examine the relationship of the bacterial flora, the intestinal barrier and the probiotics as, according to the latest knowledge, demonstrate an interesting interaction.

Drug-induced acute liver failure and gastrointestinal complications

The objective of this article is to describe adverse drug events related to the liver and gastrointestinal tract in critically ill patients. PubMed and other resources were used to identify information related to drug-induced acute liver failure, gastrointestinal hypomotility, constipation, diarrhea, gastrointestinal bleeding, and pancreatitis in critically ill patients. This information was reviewed, and data regarding pathophysiology, common drug causes, and guidelines for prevention and management were collected and summarized. In cases in which data in critically ill patients were unavailable, data were extrapolated from other patient populations. Drug-induced acute liver failure can be caused by many drugs routinely used in the intensive care unit and may be associated with significant morbidity and mortality. Drug-related hypomotility and constipation and drug-related diarrhea are reported with many drugs, and these are common adverse drug events in critically ill patients that can substantially complicate the care of these patients. Drug-induced gastrointestinal bleeding and drug-induced pancreatitis occur less frequently, can range in disease severity, and can be associated with morbidity and mortality. Many drugs used in critically ill patients are associated with adverse drug events related to the liver and gastrointestinal tract. Critical care clinicians should be aware of common drug causes of drug-induced acute liver failure, gastrointestinal hypomotility, constipation, diarrhea, gastrointestinal bleeding, and pancreatitis, and should be familiar with the prevention and management of these diverse conditions.

Critical illness, gastrointestinal complications, and medication therapy during enteral feeding in critically ill adult patients

Critically ill patients who are subjected to high stress or with severe injury can rapidly break down their body protein and energy stores. Unless adequate nutrition is provided, malnutrition and protein wasting may occur, which can negatively affect patient outcome. Enteral nutrition (EN) is the mainstay of nutrition support therapy in patients with a functional gastrointestinal (GI) tract who cannot take adequate oral nutrition. EN in critically ill patients provides the benefits of maintaining gut functionality, integrity, and immunity as well as decreasing infectious complications. However, the ability to provide timely and adequate EN to critically ill patients is often hindered by GI motility disorders and complications associated with EN. This paper reviews the GI complications and intolerances associated with EN in critically ill patients and provides recommendations for their prevention and treatment. It also addresses the role of commonly used medications in the intensive care unit and their impact on GI motility and EN delivery.

Managing opioid-induced constipation in advanced illness: focus on methylnaltrexone bromide

Constipation is a common symptom in palliative care patients which can generate considerable suffering. There is uncertainty about the choice of treatment options from varying recommendations for management of constipation and a varying clinical practice in palliative care settings. The purpose of the review was to evaluate the current recommendations of therapy guidelines for the management of opioid-induced constipation in palliative care patients with a focus on methylnaltrexone bromide. Recent findings in the literature and related information on the opioid-induced gastrointestinal disorders in patients with advanced illness, as well as information on the opioid-antagonist methylnaltrexone, are discussed. Knowledge of the role of definitions, the causes of constipation and the pathophysiology of opioid-induced constipation must be given high priority in the treatment of patients receiving opioids. Diagnosis and therapy of constipation, therefore, should relate to findings in clinical investigation. Opioid-induced constipation and its adequate treatment is an important issue for patients with advanced illness and also poses therapeutic challenge for clinicians in daily routine. Methylnaltrexone bromide may represent an important therapeutic option for palliative care patients who are suffering from opioid-induced constipation with failure of conventional prophylactic oral laxative treatment.