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

Serial Measurements of Refractive Index, Glucose and Protein to Assess Gastric Liquid Nutrient Transport—A Proof-of-Principal Study

Delayed gastric emptying contributes to complications as aspiration or malnutrition. Among patients suffering from acute neurological diseases, motility disorders are prevalent but poorly understood. Thus, methods to measure gastric emptying are required to allow for appropriate adaptions of individual enteral nutrition algorithms. For enterally fed patients repetitive concentration measurements of gastric content have been proposed to assess gastric emptying. This approach can be used to calculate the gastric residual volume (GRV) and transport of nutrition formula (NF), but it has not yet been implemented in clinical routine. The aim of this study was to investigate whether refractometry or other likewise straightforward analytical approaches produce the best results under in vitro conditions mimicking the gastric milieu. We measured NF in different known concentrations, either diluted in water or in simulated gastric fluid (SGF), with each of the following methods: refractometer, handheld glucose meter, and Bradford protein assay. Then, in enterally fed patients suffering from acute neurological disease, we calculated GRVs and nutrition transport and tested possible associations with clinical parameters. In water dilution experiments, NF concentrations could be assessed with the readout parameters of all three methods. Refractometry yielded the most precise results over the broadest range of concentrations and was biased least by the presence of SGF (detection range for Fresubin original fibre, given as volume concentration/normalized error of regression slope after incubation with water or SGF: 0–100 vs. 0–100%/0.5 vs. 3.9%; glucose-measurement: 5–100 vs. 25–100%/7.9 vs. 6.1%; Bradford-assay: 0–100 vs. 0–100%/7.8 vs. 15.7%). Out of 28 enterally fed patients, we calculated significant slower nutrition transport in patients with higher blood glucose (Rho −0.391; p = 0.039) and in patients who received high-dose sufentanil (Rho −0.514; p = 0.005). Also, the calculated nutrition transport could distinguish patients with and without feeding intolerance (Median 6 vs. 17 ml/h; Mann-Whitney test: p = 0.002). The results of our study prove that serial refractometry is a suitable and cost-effective method to assess gastric emptying and to enhance research on gastrointestinal complications of stroke.

Nasogastric- vs. percutaneous gastrostomy tube for prophylactic gastric decompression after cytoreductive surgery with hyperthermic intraperitoneal chemotherapy

Objectives

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is associated with postoperative gastroparesis and ileus. In 2015, our practice shifted from using percutaneous gastrostomy tubes (PGT), to nasogastric tubes (NGT) for prophylactic gastric decompression after CRS-HIPEC. This study aimed to compare these methods for length of stay (LOS) and associated complications.

Methods

Patients that underwent CRS-HIPEC for peritoneal metastases from colorectal cancer between 2014 and 2019 were included. Cases were grouped based on receiving NGT or PGT postoperatively. Multivariable linear regression determined the independent effect of decompression method on LOS, thereby adjusting for confounders.

Results

In total, 179 patients were included in the analyses. Median age was 64 years [IQR:54–71]. Altogether, 135 (75.4%) received a NGT and 44 (24.6%) received a PGT. Gastroparesis occurred significantly more often in the PGT group (18.2 vs. 7.4%, p=0.039). Median LOS was significantly shorter for patients with a NGT (15 [IQR:12–19] vs. 18.5 [IQR:17–25.5], p<0.001). PGT was independently associated with longer LOS in multivariable analysis (Beta=4.224 [95%CI 1.243–7.204]). There was no difference regarding aspiration, pneumonia and postoperative mortality between groups.

Conclusions

NGT should be preferred over PGT for gastric decompression after CRS-HIPEC as it is associated with fewer gastroparesis and shorter LOS.

Aspiration pneumonia and pneumonitis: a spectrum of infectious/noninfectious diseases affecting the lung

PURPOSE OF REVIEW

Our purpose is to describe aspiration pneumonia/pneumonitis as a spectrum of infectious/noninfectious diseases affecting the lung. We summarize diagnosis, risk factors, treatment, and strategies for prevention of aspiration.

RECENT FINDINGS

Aspiration is present in normal individuals, and disease manifestation depends on the chemical characteristics, frequency, and volume of inoculum. Anaerobes, though present, are no longer the predominant microbes isolated in aspiration pneumonia. Targets for preventing aspiration including improved oral hygiene and positional feeding have had mixed results. Patients diagnosed by clinicians with aspiration pneumonia experience greater morbidity and mortality than patients with community-acquired pneumonia.

SUMMARY

Aspiration pneumonia and pneumonitis are part of the pneumonia continuum and share similarities in pathophysiology, microbiology, and treatment. Modern microbiology demonstrates that the lung is not sterile, and isolates in aspiration pneumonia frequently include aerobes or mixed cultures. Treatment for aspiration pneumonia should include antibiotic coverage for oral anaerobes, aerobes associated with community-acquired pneumonia, and resistant organisms depending on appropriate clinical context. Additional studies targeting prevention of aspiration and investigating the increased morbidity and mortality associated with aspiration pneumonia are warranted.

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

Background

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

Methods

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

Discussion

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

Trial registration

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

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Comparison of Two Different Methods for the Measurement of Gastric Residual Volume

The objective of this study was to determine the difference between gastric residual volume measurements without giving air compared to giving 30 ml of air via the feeding tube. This experimental study was on 60 subjects fed enterally at a university hospital. Data collection was with the 12-item "Gastric Residual Volume Measurement Instructions" and "Gastric Residual Volume Observation Form." The same subjects composed experimental and control groups. Gastric residual volume measurements were taken before feedings at 10:00 a.m., 1:00 p.m., and 4:00 p.m. with a 60-ml syringe. First measurement was taken without giving air by withdrawing the syringe piston at 2-3 ml/second. Second measurement was applied by giving 30 ml of air and withdrawing the piston at the same speed. Student's t test was used for data analysis. A total of 180 measurements were made for each method. Gastric residual volume averages were 3.71 ± 7.97 ml without air and 3.78 ± 8.08 ml with air. The difference between averages was statistically significant (p < .05). Difficulties withdrawing the syringe piston without giving air occurred in 85% of the intermittently enterally fed patients and 22.8% of those fed continuously. Gastric residual volume measurements with air were higher than those without air. The aspiration procedure with air was easier. Gastric residual volume measurements should be made with 30 ml of air and by withdrawing the syringe piston at 2-3 ml/minute.

Pneumonitis and pneumonia after aspiration

Aspiration pneumonitis and aspiration pneumonia are clinical syndromes caused by aspiration. These conditions are clinically significant due to their high morbidity and mortality. However, aspiration as a preceding event are often unwitnessed, particularly in cases of asymptomatic or silent aspiration. Furthermore, despite the difference in treatment approaches for managing aspiration pneumonitis and aspiration pneumonia, these two disease entities are often difficult to discriminate from one another, resulting in inappropriate treatment. The use of unclear terminologies hinders the comparability among different studies, making it difficult to produce evidence-based conclusions and practical guidelines. We reviewed the most recent studies to define aspiration, aspiration pneumonitis, and aspiration pneumonia, and to further assess these conditions in terms of incidence and epidemiology, pathophysiology, risk factors, diagnosis, management and treatment, and prevention.

Devices and Techniques for Bedside Enteral Feeding Tube Placement

Enteral feedings are an integral part of care for many hospitalized patients. Accessing the gastrointestinal (GI) tract safely and in a timely manner can be challenging. Various techniques and devices to enhance the safety of bedside feeding tube placement are available for clinicians. Three specific devices are highlighted, including the colorimetric CO(2) detector (CCD), a magnetically guided feeding tube (MGFT), and the electromagnetic tube placement device (ETPD). The CO(2) detector is applied to detect the presence or absence of CO(2), thus assisting in correct placement of the feeding tube tip into the GI tract vs the lung. The MGFT uses a magnetic device to manipulate the feeding tube through the GI tract into the small intestine. The ETPD provides real-time visualization of the feeding tube as it progresses into the small intestine. Training and repetition are essential for safe and successful feeding tube placement, and the highlighted devices can contribute to both of these goals.

Comparison of Two Different Enteral Nutrition Protocol in Critically Ill Patients

OBJECTIVE

In this study, two enteral nutrition protocols with different gastric residual volumes (GRVs) and different monitoring intervals were compared with respect to gastrointestinal intolerance findings in intensive care unit (ICU) patients.

METHODS

The study was carried out prospectively in 60 patients in the anaesthesiology and reanimation ICU under mechanical ventilation support, who were scheduled to take enteral feeding. Patients were sequentially divided into two groups: Group 1, GRV threshold of 100 mL, and monitoring interval of 4 hours, and Group 2, GRV threshold of 200 mL, monitoring interval of 8 hours. To test the significant difference between the groups, Student's t test, chi-square text and Fisher exact test were used.

RESULTS

In Group 1, 3.3% vomiting, 6.6% diarrhoea was observed; in Group 2, 16.6% vomiting, 10% diarrhoea. In terms of total intolerance (vomiting and/or diarrhoea) of the two groups, the incidence was significantly higher in Group 2 (33.3%) than in Group 1 (10%) (p=0.02).

CONCLUSION

According to the results of the study, a lower gastrointestinal intolerance rate was detected in the GRV threshold 100 mL, monitoring interval for 4 hours protocol (Group 1) than in GRV threshold 200 mL, monitoring interval for 8 hours protocol (Group 2); Group 1 may be preferred renovation.

Aspiration pneumonia: a review of modern trends

PURPOSE

The purpose was to describe aspiration pneumonia in the context of other lung infections and aspiration syndromes and to distinguish between the main scenarios commonly implied when the terms aspiration or aspiration pneumonia are used. Finally, we aim to summarize current evidence surrounding the diagnosis, microbiology, treatment, risks, and prevention of aspiration pneumonia.

MATERIALS AND METHODS

Medline was searched from inception to November 2013. All descriptive or experimental studies that added to the understanding of aspiration pneumonia were reviewed. All studies that provided insight into the clinical aspiration syndromes, historical context, diagnosis, microbiology, risk factors, prevention, and treatment were summarized within the text.

RESULTS

Despite the original teaching, aspiration pneumonia is difficult to distinguish from other pneumonia syndromes. The microbiology of pneumonia after a macroaspiration has changed over the last 60 years from an anaerobic infection to one of aerobic and nosocomial bacteria. Successful antibiotic therapy has been achieved with several antibiotics. Various risks for aspiration have been described leading to several proposed preventative measures.

CONCLUSIONS

Aspiration pneumonia is a disease with a distinct pathophysiology. In the modern era, aspiration pneumonia is rarely solely an anaerobic infection. Antibiotic treatment is largely dependent on the clinical scenario. Several measures may help prevent aspiration pneumonia.

Gastroesophageal reflux in critically ill patients

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

Posaconazole plasma concentrations in critically ill patients

BACKGROUND

Posaconazole is an azole antifungal agent with a broad spectrum of activity and a manageable side-effect profile. Although the pharmacokinetics of posaconazole have been described in healthy volunteers who received the drug by means of a nasogastric tube or with nutritional supplements, the pharmacokinetics of posaconazole have not been reported in critically ill patients.

METHODS

Twenty-seven patients in the general intensive care unit managed according to standard protocols were randomly allocated to dose regimens of either 400 mg twice daily or 200 mg 4 times daily. Plasma samples were collected for pharmacokinetic analysis after the first dose and at steady-state. Posaconazole plasma concentrations were compared with suggested effect targets for prophylaxis and treatment.

RESULTS

Mean Cmin steady-state plasma concentrations of posaconazole were low for both regimens (306 and 137 ng/mL for 400 mg twice daily and 200 mg 4 times daily regimens, respectively), as was total exposure to posaconazole in each group [area under the concentration-time curve (AUC0-t) for first dose: 761 and 299 μg·h/L]. Only 17% of patients achieved steady-state Cmin posaconazole plasma concentrations above the suggested target for prophylaxis, and only one patient had a Cmin posaconazole concentration that exceeded the suggested target for treatment effect. Systemic exposure to posaconazole seemed to be subtherapeutic in most patients in this cohort. Poor absorption of posaconazole due to drug interactions may explain the low systemic exposure; however, further investigation is necessary.

CONCLUSIONS

These data suggest that there is a need for an intraveneous formulation of the drug if it is to be used effectively in critically ill patients, and therapeutic drug monitoring is an essential tool in this setting to identify patients with low systemic exposure to prevent therapeutic failure.

Impact of disease severity on gastric residual volume in critical patients

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

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

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

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

To return or to discard? Randomised trial on gastric residual volume management

BACKGROUND

The control of gastric residual volume (GRV) is a common nursing intervention in intensive care; however the literature shows a wide variation in clinical practice regarding the management of GRV, potentially affecting patients' clinical outcomes. The aim of this study is to determine the effect of returning or discarding GRV, on gastric emptying delays and feeding, electrolyte and comfort outcomes in critically ill patients.

METHOD

A randomised, prospective, clinical trial design was used to study 125 critically ill patients, assigned to the return or the discard group. Main outcome measure was delayed gastric emptying. Feeding outcomes were determined measuring intolerance indicators, feeding delays and feeding potential complications. Fluid and electrolyte measures included serum potassium, glycaemia control and fluid balance. Discomfort was identified by significant changes in vital signs.

RESULTS

Patients in both groups presented similar mean GRV with no significant differences found (p=0.111), but participants in the intervention arm showed a lower incidence and severity of delayed gastric emptying episodes (p=0.001). No significant differences were found for the rest of outcome measurements, except for hyperglycaemia.

CONCLUSIONS

The results of this study support the recommendation to reintroduce gastric content aspirated to improve GRV management without increasing the risk for potential complications.

Inhibition of gastroesophageal reflux by semi-solid nutrients in patients with percutaneous endoscopic gastrostomy

BACKGROUND

Aspiration is one of the major complications after percutaneous endoscopic gastrostomy (PEG). The administration of semi-solid nutrients by means of gastrostomy tube has recently been reported to be effective in preventing aspiration pneumonia. The effects of semi-solid nutrients on gastroesophageal reflux, intragastric distribution, and gastric emptying were evaluated.

METHODS

Semi-solid nutrients were prepared by liquid nutrients mixed with agar at the concentration of 0.5%. The distribution of the administered radiolabeled liquid and semi-solid nutrients was monitored by a scintillation camera for 15 post-PEG patients. The percentage of esophageal reflux, the distribution of the proximal and distal stomach, and the gastric emptying time were evaluated.

RESULTS

The percentage of gastroesophageal reflux was significantly decreased in semi-solid nutrients (0.82 +/- 1.27%) compared with liquid nutrients (3.75 +/- 4.25%), whereas the gastric emptying time was not different. The distribution of semi-solid nutrients was not different from liquid nutrients in the early phase, whereas higher retention of liquid nutrients in the proximal stomach was observed in the late phase.

CONCLUSIONS

Gastroesophageal reflux was significantly inhibited by semi-solid nutrients. One of the mechanisms of the inhibition is considered to be an improvement in the transition from the proximal to distal stomach in semi-solid nutrients.

[Measurement of residual gastric volume: in search of better evidence]

INTRODUCTION

Measurement of residual gastric volume is a frequent practice in chronic patients, but there is lack of consensus on the convenience of reintroducing or discarding aspirated gastric content (AGC).

OBJECTIVE

Determine the grade of scientific evidence on the efficacy of two interventions -reintroduction/rejection- of AGC in chronic patients.

MATERIAL AND METHODS

Systematic review of the evidence available on the convenience of reintroducing or discarding ACG.

PROCEDURE

a) establishment of inclusion/exclusion criteria; b) determination of the search strategy (keywords and itineraries); c) dumping of databases: MEDLINE, CINAHL, CUIDEN, IME, SCIELO and COCHRANE. Search for indirect method and manual dumping of indexes; d) independent and contrasted critical reading, using the CASPe template; and e) contrast of critical analysis results.

RESULTS

Search itineraries generate more than 800 references that once purged make it possible to select 54. After reading them, only 4 really focused on the questions related with the reintroduction/rejection of AGC: 2 revisions, 1 observational study and a random clinical trial with a small sample. Meta-analysis techniques could not be used due to the heterogeneity of these studies. Thus, the results of the study were analyzed separately. Using this procedure, a final result was obtained that showed a low grade of scientific evidence.

CONCLUSIONS

There is limited scientific evidence on the convenience, safety and benefits of both interventions. It is difficult to establish a care protocol, so that we suggest performing an experimental study to establish the indications and contraindications of both interventions.

Using Evidence in Home Care: The Value of a Librarian-Clinician Collaboration—the Clinician’s Role

Evidence-based practice is a natural process for the inquiring home care nurse who wants to provide the highest quality of care. A critical step in the process is finding the best evidence and employing appropriate expertise and resources to facilitate the search. This critical step can be more easily accomplished with a collaborative partnership involving a reference librarian and the clinician. In this process, each uses his or her unique expertise to search for the best evidence to support practice decisions. Examples are given of current relevant evidence for health care clinicians and suggestions for how to use the evidence in decision making.

Gastric and postpyloric total enteral nutrition

The provision and maintenance of good nutrition in patients with acute and chronic illness is a fundamental part of standard medical and surgical care. Recently, there is great interest in using enteral nutritional support to reverse the morbidity and mortality associated with malnutrition. Enteral nutrition is preferred over parenteral nutrition because it is more physiologic, maintains intestinal structure and function, limits bacterial translocation, has less morbidity, has fewer complications, and is less expensive. However, the decision to feed into the stomach or into the small bowel (postpyloric) continues to be a matter of some debate and continued clinical investigation. Although the gastric route of enteral feeding is easier and less expensive, some physicians worry that gastric feeding may predispose to aspiration and pneumonia, especially in critically ill patients who frequently have delayed gastric transit. In these critically ill patients, small bowel function usually remains relatively intact and placement of a postpyloric feeding tube may permit more effective delivery of nutrients. However, it should be noted that placement of postpyloric feeding tubes can be challenging, and this may lead to a delay in initiation of nutritional support.

The effects of long-term total parenteral nutrition on gut mucosal immunity in children with short bowel syndrome: a systematic review

BACKGROUND: Short bowel syndrome (SBS) is defined as the malabsorptive state that often follows massive resection of the small intestine. Most cases originate in the newborn period and result from congenital anomalies. It is associated with a high morbidity, is potentially lethal and often requires months, sometimes years, in the hospital and home on total parenteral nutrition (TPN). Long-term survival without parenteral nutrition depends upon establishing enteral nutrition and the process of intestinal adaptation through which the remaining small bowel gradually increases its absorptive capacity. The purpose of this article is to perform a descriptive systematic review of the published articles on the effects of TPN on the intestinal immune system investigating whether long-term TPN induces bacterial translocation, decreases secretory immunoglobulin A (S-IgA), impairs intestinal immunity, and changes mucosal architecture in children with SBS. METHODS: The databases of OVID, such as MEDLINE and CINAHL, Cochran Library, and Evidence-Based Medicine were searched for articles published from 1990 to 2001. Search terms were total parenteral nutrition, children, bacterial translocation, small bowel syndrome, short gut syndrome, intestinal immunity, gut permeability, sepsis, hyperglycemia, immunonutrition, glutamine, enteral tube feeding, and systematic reviews. The goal was to include all clinical studies conducted in children directly addressing the effects of TPN on gut immunity. RESULTS: A total of 13 studies were identified. These 13 studies included a total of 414 infants and children between the ages approximately 4 months to 17 years old, and 16 healthy adults as controls; and they varied in design and were conducted in several disciplines. The results were integrated into common themes. Five themes were identified: 1) sepsis, 2) impaired immune functions: In vitro studies, 3) mortality, 4) villous atrophy, 5) duration of dependency on TPN after bowel resection. CONCLUSION: Based on this exhaustive literature review, there is no direct evidence suggesting that TPN promotes bacterial overgrowth, impairs neutrophil functions, inhibits blood's bactericidal effect, causes villous atrophy, or causes to death in human model.The hypothesis relating negative effects of TPN on gut immunity remains attractive, but unproven. Enteral nutrition is cheaper, but no safer than TPN. Based on the current evidence, TPN seems to be safe and a life saving solution.