Impact of early high caloric duodenal feeding on the oxygen balance of the splanchnic region after severe burn injury

Enteral Resuscitation: A Field-Expedient Treatment Strategy for Burn Shock during Wartime and in Other Austere Settings

Burn injuries are a constant threat in war. Aspects of the modern battlefield increase the risk of burn injuries and pose challenges for early treatment. The initial resuscitation of a severely burn-injured patient often exceeds the resources available in front-line medical facilities. This stems mostly from the weight and volume of the intravenous fluids required. One promising solution to this problem is enteral resuscitation with an oral rehydration solution. In addition to being logistically easier to manage, enteral resuscitation may be able to mitigate secondary injuries to the gut related to burn shock and systemic immunoinflammatory activation. This has been previously studied in burn patients, primarily using electrolyte solutions, with promising results. Modern ORS containing sodium, potassium, and glucose in ratios that maximize gut absorption may provide additional benefits as a resuscitation strategy, both in terms of plasma volume expansion and protection of the barrier and immune functions of the gut mucosa. While enteral resuscitation is promising and should be used when other options are not available, further research is needed to refine an optimal implementation strategy.

When is enteral nutrition indicated?

Enteral nutrition (EN) is a vital component of nutrition around the world. EN allows for delivery of nutrients to those who cannot maintain adequate nutrition by oral intake alone. Common questions regarding EN are when to initiate and in what scenarios it is safe. The answers to these questions are often complex and require an evidence-based approach. The Board of Directors of the American Society for Parenteral and Enteral Nutrition (ASPEN) established an Enteral Nutrition Committtee to address the important questions surrounding the indications for EN. Consensus recommendations were established based on eight extremely clinically relevant questions regarding EN indications as deemed by the Enteral Nutrition Committee. These consensus recommendations may act as a guide for clinicians and stakeholders on difficult questions pertaining to indications for EN. This paper was approved by the ASPEN Board of Directors.

Evaluating the Safety and Efficacy of Intraoperative Enteral Nutrition in Critically Ill Burn Patients: A Systematic Review and Meta-analysis

Major burn injuries incite a hypermetabolic response, and the initiation of early enteral nutrition is the standard of care in patients with large burns and contributes to improved outcomes. Perioperative fasting is a common cause of caloric deficits in burn patients and can be obviated with intraoperative enteral nutrition. However, the risks and benefits of this practice are unknown, and there is a concern for aspiration. We conducted a systematic review and meta-analysis to evaluate the safety and efficacy of intraoperative enteral nutrition. We performed a systematic literature search using PubMed, Scopus, and OvidSP MEDLINE databases. We identified studies that evaluated the effects of intraoperative enteral nutrition in adult burn patients compared to those undergoing routine perioperative fasting. We performed a meta-analysis on the incidence of mortality, pneumonia, wound infections, and aspiration in burn patients receiving intraoperative enteral nutrition. We identified seven articles for qualitative review and four for quantitative review (N = 83 patients). There were no statistically significant increases in the risk of mortality (odds ratio [OR] = 1.28, 95% confidence interval [CI]: 0.49, 3.31), wound infections (OR = 0.71, 95% CI: 0.16, 3.24), pneumonia (OR = 2.1, 95% CI: 0.7, 6.1), and aspiration (OR = 1.14, 95% CI: 0.07, 18.75) in patients receiving intraoperative enteral nutrition. Within individual studies, intraoperative enteral nutrition patients received significantly more calories than standard fasting patients. Intraoperative enteral nutrition may increase nutritional intake in burn patients without an increase in complications; however, this is based on limited studies. Randomized controlled trials are needed before recommendations on intraoperative enteral nutrition practice can be made.

Early Initiation of Post-Pyloric Feeding in Patients with Major Burns: Experience in Taiwan Formosa Water Park Dust Explosion Disaster

Early initiation of enteral nutrition improves clinical outcomes in critical patients with serious burns. Post-pyloric tube feeding is a valuable therapeutic option for severely burned patients with poor gastric emptying. How early post-pyloric feeding can be initiated to provide more benefits to patients has not yet been examined. A fire erupted at a recreational water park in New Taipei City, Taiwan, on June 27, 2015. The results of early initiation versus delayed post-pyloric feeding in severely burned patients in this mass-casualty incident were compared. Door-to-post-pyloric feeding time ≤ 24 h was considered as early post-pyloric feeding (EPF) and that > 24 h was considered as delayed post-pyloric feeding (DPF). Thirteen patients with severe burn injuries (> 40% of the total body surface area) were assigned to undergo either EPF (five patients) or DPF (eight patients). This study is a "fortuitously controlled" study, and the authors were able to formulate and test whether EPF is better than DPF by comparing the two groups. In patients in the EPF, the intake of calories increased rapidly and was maintained throughout the study period. In addition, rapid restoration of plasma magnesium concentrations as well as pronounced recovery of platelet count in the EPF group was observed. In conclusion, our findings indicate that the time from injury to the onset of post-pyloric feeding is crucial, and EPF allows for the administration of calculated caloric needs. Therefore, EPF can be successfully initiated with beneficial outcomes of nutritional reconstruction in severely burned patients.

Early enteral nutrition in critically ill patients with hemodynamic instability: an evidence-based review and practical advice

Early enteral nutrition (EEN) in critically ill patients is associated with significant benefit as well as elevated risk of complications. Concomitant use of EEN with vasopressors has been associated with nonocclusive bowel necrosis in critically ill patients with hemodynamic instability. The decision when to initiate enteral nutrition in hemodynamically unstable patients that require vasoactive substances remains a clinical dilemma. This review summarizes the effect of EEN and vasoactive agents on gastrointestinal blood flow and perfusion in critically ill patients, based on current evidence. Animal and clinical data involving simultaneous administration of EEN and vasoactive agents for hemodynamic instability are reviewed, and the factors related to the safety and effectiveness of EEN support in this patient population are analyzed. Moreover, practical recommendations are provided. Additional randomized clinical trials are warranted to provide cutting-edge evidence-based guidance about this issue for practitioners of critical care.

Effect of early enteral nutrition on morbidity and mortality in children with burns

Burns increase the metabolic demands of the body and can lead to severe weight loss and increased risk of death. Early enteral support is believed to improve gastrointestinal, immunological, nutritional and metabolic responses to critical injury; however, this premise is in need of further substantiation by definitive data. This research aimed to examine the effectiveness and safety of early enteral feeding in paediatric patients suffering from burns.

MATERIALS AND METHODS

This clinical trial was carried out with a total number of 688 children with burns hospitalised in the Burn Department across a 2-year period (September 2002-September 2004). The subjects were randomised into two groups. A total of 322 patients received only intravenous resuscitation, in accordance with current treatment protocols, in the first 48 h and were considered as the late enteral nutrition group (LEN group); 366 patients were nourished early enteral nutrition group (EEN group), such that both groups received similar amounts of fluid in the first 48 h. Initiation of enteral nutrition commenced between 3 and 6 h following the burn. The patients were kept in the unit until they were discharged. Wound management did not vary between groups.

RESULTS

In our study, the mean age was 5±3 years in the LEN group and 5±3.5 years in the EEN group. Hot liquids were the most common cause of burns in both groups. The mean percentage of burn was reported as 20±13 in the LEN group and 22±15 in the EEN group. Mean duration of hospitalisation was 16.4±3.7 days in the LEN group and 12.6±1.3 in the EEN group for cured patients (P<0.05). A total of 40 patients (12%) in the LEN group and 31 patients (8.5%) in the EEN group expired (P<0.05).

CONCLUSION

Our research showed that EEN decreases duration of hospitalisation and mortality in children with burns.

Intestinal and gastric tonometry during experimental burn shock

INTRODUCTION

The occurrence of organ failure following thermal injury, despite restoration of hemodynamic parameters and urine output during resuscitation, has led to efforts to measure end-organ perfusion. The purpose of this 24-h study was to evaluate the utility of gastrointestinal (GI) tonometry during burn shock and resuscitation.

METHODS

Male swine (n=11, 23.3+/-0.9 kg) were anesthetized with ketamine and propofol. A 70% full thickness burn was caused by immersion in 97 degrees C water for 30 s. Resuscitation with lactated Ringer's, 4 ml/kg/% burn, was begun at hour 6 and titrated to urine output (UO). Arterial blood gases and pulmonary artery catheter data were measured every 6 h. Gastric and ileal regional PCO(2) (PrCO(2)) were measured continuously by air tonometry, and the gastric and ileal intramucosal pH (pHi) and PCO(2) gap (PrCO(2)-PaCO(2)) were calculated every 6 h.

RESULTS

Gastric pHi, ileal PrCO(2), ileal pHi, and ileal PCO(2) gap (but not gastric PrCO(2) or PCO(2) gap) all decreased with shock and were restored to baseline levels by resuscitation. Changes in ileal PrCO(2) were of greater magnitude and demonstrated decreased variability than those in gastric PrCO(2).

CONCLUSIONS

In this model, ileal tonometry outperformed gastric tonometry during burn shock and resuscitation.

Early versus late enteral nutritional support in adults with burn injury: a systematic review

BACKGROUND

Burn injury increases the body's metabolic demands, and therefore nutritional requirements. Provision of an adequate supply of nutrients is believed to lower the incidence of metabolic abnormalities, thus reducing septic morbidity, and improving survival rates. Enteral nutrition support is the best feeding method in a patient who is unable to achieve an adequate oral intake, but optimal timing of its introduction after burn injury (i.e. early versus late) needs to be established. The purpose of this review is to examine evidence for the effectiveness and safety of early versus late enteral nutrition support in adults with burn injury.

METHODS

An examination of randomized and controlled clinical trials using various medical databases such as The Cochrane Library (Issue 3, 2006), MEDLINE (from 1950), CINHAL (from 1982) and EMBASE (from 1980).

RESULTS

The trial evidence about the benefit of early enteral nutritional support on standardized clinical outcomes such as length of hospital stay and mortality remained inconclusive. Similarly, the question of whether early enteral feeding influenced or decreased metabolic rate, reduced septic and other complications remained uncertain.

CONCLUSIONS

Promising results suggest early enteral nutrition support may blunt the hypermetabolic response to thermal injury, but it is insufficient to provide clear guidelines for practice. Further research incorporating larger sample sizes and rigorous methodology that utilizes valid and reliable outcome measures is essential.

Early versus delayed enteral nutrition support for burn injuries

BACKGROUND

A burn injury increases the body's metabolic demands, and therefore nutritional requirements. Provision of an adequate supply of nutrients is believed to lower the incidence of metabolic abnormalities, thus reducing septic morbidity, improving survival rates, and decreasing hospital length of stay. Enteral nutrition support is the best feeding method for patients who are unable to achieve an adequate oral intake to maintain gastrointestinal functioning, however, its timing (i.e. early versus late) needs to be established.

OBJECTIVES

To assess the effectiveness and safety of early versus late enteral nutrition support in adults with burn injury.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library, issue 1, 2006), the Cochrane Injuries Group's Specialised Register, MEDLINE (1966 to May week 1, 2006), EMBASE (1980 to week 17, 2005) and CINAHL (1982 to May week 1, 2006).

SELECTION CRITERIA

We included all randomised controlled trials comparing early enteral nutrition support (within 24 hours of injury) versus delayed enteral support (greater than 24 hours).

DATA COLLECTION AND ANALYSIS

Two authors used standardised forms to independently extract the data. Each trial was assessed for internal validity with differences resolved by discussion.

MAIN RESULTS

A total of three randomised controlled trials were eligible for inclusion in this review. Results of the studies indicate that evidence about the benefit of early enteral nutritional support on standardised clinical outcomes such as length of hospital stay and mortality, remains inconclusive. Similarly, the question of whether early enteral feeding influenced or decreased metabolic rate as documented in part by our included studies, remains uncertain.

AUTHORS' CONCLUSIONS

This systematic review has not found sufficient evidence to support or refute the effectiveness of early versus late enteral nutrition support in adults with burn injury. The trials showed some promising results that would suggest early enteral nutrition support may blunt the hypermetabolic response to thermal injury, but this is insufficient to provide clear guidelines for practice. Further research incorporating larger sample sizes and rigorous methodology that utilises valid and reliable outcome measures, is essential.

Burns, bacterial translocation, gut barrier function, and failure

The development of systemic inflammation, acute lung injury, and multiple organ failure after a major thermal injury, as well as nonthermal forms of trauma, remain relatively common causes of morbidity and mortality. During the past two decades, increasing recognition that the ischemic gut may contribute to the development of sepsis and organ failure in burn patients, as well as other critically ill patient populations, has led to new hypotheses to explain burn-induced multiple organ failure as well as highlighted the importance of early enteral nutrition. Thus, the goal of this review will be to provide a perspective on the evolution of the gut hypothesis of systemic inflammation and distant organ dysfunction.

Impact of intraoperative duodenal feeding on the oxygen balance of the splanchnic region in severely burned patients

Enteral feeding causes an increase of intestinal oxygen demand depending on the amount administered. The aim of this study presented was to evaluate, whether intraoperative duodenal feeding might put patients at risk developing splanchnic O(2)-imbalance due to an intraoperatively compromised intestinal perfusion based on stress and unrecognized hypovolemia. In 18 severely burned patients, the CO(2)-gap between the arterial and gastric CO(2), as a parameter for the intestinal O(2)-balance, was measured during the first operation. All operations were performed on day 3-5 after admission and lasted for 4-5h. Half of the patients (nine patients) were fed intraoperatively, whereas in the other nine patients feeding was suspended beginning 1h prior to surgery until 6h after surgery. CO(2)-gap measurements were carried out prior to surgery, hourly during the operation and 5h postoperatively. Measurements 3 and 4h after beginning of the operation revealed significantly higher CO(2)-gap values in the fasting group. All other measurements showed no significant difference between both groups. Therefore, intraoperative enteral nutrition, at least in the early postburn phase, is not only necessary for reducing caloric deficits, but also seems to have a protective effect on gut oxygen balance.

Nutrition and anabolic agents in burned patients

PURPOSE OF REVIEW

Much of the morbidity and mortality of severely burned patients is connected with hypermetabolism and catabolism with its accompanying impairment of wound healing and increased infection risks. In order to prevent the erosion of body mass, nutritional support and other strategies to prevent catabolism have become a major focus in the care of severely burned patients.

RECENT FINDINGS

Major themes discussed in recent literature are dealing with enteral versus parenteral nutrition and gastric versus duodenal feeding. The possibility of overfeeding is another important aspect of high calorie nutrition as commonly used in burned patients. Specific formulas for enteral nutrition for specific metabolic abnormalities are under evaluation as well as the role of anabolic and anticatabolic agents.

SUMMARY

From the clinical literature, total enteral nutrition starting as early as possible without any supplemental parenteral nutrition is the preferred feeding method for burned patients. Using a duodenal approach, especially in the early postburn phase, seems to be superior to gastric feeding. Administration of high calorie total enteral nutrition in any later septic phase should be critically reviewed due to possible impairment of splanchnic oxygen balance. Therefore, measurement of CO(2)-gap should be considered as a monitoring method during small bowel nutrition. The impact on the course of disease of supplements such as arginine, glutamine and vitamins as well as the impact of the use of anabolic and anticatabolic agents is not yet evident. Furthermore, the effect of insulin administration and low blood sugar regimes on wound healing and outcome in burned patients should be evaluated in future studies.

Enteral feeding

In this review, topics with scientific strength, topical interest, and controversy were selected. Over the past 50 years, malnutrition has become increasingly recognized as a cause of increased morbidity and mortality in hospital patients. From 1970 to 1980, parenteral nutrition was advocated as the most appropriate form of nutritional therapy for hospital patients. Since then, parenteral nutrition has been replaced by enteral nutrition as the best way of delivering nutrients to hospital patients. The timing of enteral nutrition has been debated. Should it be instituted early, within the first 24 hours? In addition, enteral nutrition containing immune-enhancing nutrients such as arginine, omega-3 fatty acids, glutamine, and nucleotides has been advocated for critically ill patients. The relative merits of enteral versus total parenteral nutrition continue to be debated. Questions about possible complications related to enteral nutrition have been raised. Patients are at risk of nosocomial pneumonia from aspiration and at risk of bowel ischemia because enteral nutrition increases intestinal oxygen consumption. Steroids are often used to treat Crohn disease, but because of undesirable side effects, various techniques have been used to reduce steroid dependency. Enteral nutrition has been advocated as a way of reducing steroid dependency. Finally, enteral nutrition is routinely used to feed demented patients and those in a vegetative state. It is not clear whether this practice alters outcome or quality of life.

Enteral feeding

In this review, topics with scientific strength, topical interest, and controversy were selected. Over the past 50 years, malnutrition has become increasingly recognized as a cause of increased morbidity and mortality in hospital patients. From 1970 to 1980, parenteral nutrition was advocated as the most appropriate form of nutritional therapy for hospital patients. Since then, parenteral nutrition has been replaced by enteral nutrition as the best way of delivering nutrients to hospital patients. The timing of enteral nutrition has been debated. Should it be instituted early, within the first 24 hours? In addition, enteral nutrition containing immune-enhancing nutrients such as arginine, omega-3 fatty acids, glutamine, and nucleotides has been advocated for critically ill patients. The relative merits of enteral versus total parenteral nutrition continue to be debated. Questions about possible complications related to enteral nutrition have been raised. Patients are at risk of nosocomial pneumonia from aspiration and at risk of bowel ischemia because enteral nutrition increases intestinal oxygen consumption. Steroids are often used to treat Crohn disease, but because of undesirable side effects, various techniques have been used to reduce steroid dependency. Enteral nutrition has been advocated as a way of reducing steroid dependency. Finally, enteral nutrition is routinely used to feed demented patients and those in a vegetative state. It is not clear whether this practice alters outcome or quality of life.

Impact of duodenal feeding on the oxygen balance of the splanchnic region during different phases of severe burn injury

Enteral nutrition is recommended in burned patients. Depending on the amount administered, enteral feeding causes an increase of intestinal oxygen-demand. Since intestinal perfusion is decreased after major burns the aim of this study was to evaluate, whether duodenal feeding might be a cofactor for the development of a splanchnic O(2)-imbalance. In 15 severely burned patients during duodenal feeding starting within 6 h after injury the assessment of the CO(2)-gap between arterial and gastric CO(2), as a parameter for the measurement of intestinal O(2)-balance was performed. Beginning prior to enteral nutrition CO(2)-gap measurements were carried out to show when the CO(2)-gap increased above 30 mmHg during the whole critical illness phase of the patients. When the CO(2)-gap increased above 30 mmHg enteral nutrition was reduced by 50% and the CO(2)-gap was measured 1 h later. In none of the patients the CO(2)-gap increased during increase of enteral nutrition. In seven patients, the CO(2)-gap increased between the 6th and 13th day above 30 mmHg and fell significantly 1 h after reduction of enteral nutrition. Contrary to the early postburn phase, enteral feeding might have adverse effects on the oxygen balance of the intestine in the later stages of the critical illness phase.