How long are burn patients really NPO in the perioperative period and can we effectively correct the caloric deficit using an enteral feeding "Catch-up" protocol?

Association Between Nil Per Os Status and Intubated Patients Undergoing Surgery

INTRODUCTION

Patient outcomes heavily rely on nutritional support. However, holding enteric feeds prior to surgical operations in critically ill patients is still a common practice in intensive critical units. Our objective is to describe the relationship between duration of nil per os (NPO) and respiratory outcomes in intubated, critically ill patients requiring operative intervention.

METHODS

We conducted a retrospective analysis on intubated, critically ill patients who underwent operative intervention between January 1, 2016, and December 31, 2018, to investigate how the duration of NPO status may affect respiratory outcomes. We compared adverse respiratory events among patients who maintain NPO ≥6 h (NPO group) versus those who were NPO <6 h (non-NPO group) prior to surgery.

RESULTS

Two hundred patients met inclusion criteria: 104 for NPO and 96 for non-NPO. Aspiration event was found in 5.8% of NPO patients and 7.3% in non-NPO patients, P = 0.66. Desaturation event was found in 16.3% for NPO and 14.6% in non-NPO, P = 0.73. Pneumonia was found in 18.3% of NPO patients and 19.8% in non-NPO patients, P = 0.78. Reintubated rates were 13.5% for NPO and 16.7% for non-NPO, P = 0.57. Median (range) hours of NPO for non-NPO was 1.0 h (0-3.0) and 13.0 h (6.0-20.0) for NPO, P < 0.05.

CONCLUSIONS

For intubated, critically ill patients requiring operative intervention, there was no difference observed in adverse respiratory events between those kept NPO for 6 h or greater compared to those kept NPO for less than 6 h. Patients were commonly without enteric nutrition for periods of time much greater than the American Society of Anesthesia's recommended 6-h period.

Nutrition after severe burn injury

PURPOSE OF REVIEW

Severe burn injury causes significant metabolic changes and demands that make nutritional support particularly important. Feeding the severe burn patient is a real challenge in regard to the specific needs and the clinical constraints. This review aims to challenge the existing recommendations in the light of the few recently published data on nutritional support in burn patients.

RECENT FINDINGS

Some key macro- and micro-nutrients have been recently studied in severe burn patients. Repletion, complementation or supplementation of omega-3 fatty acids, vitamin C, vitamin D, antioxidant micronutrients may be promising from a physiologic perspective, but evidence of benefits on hard outcomes is still weak due to the studies' design. On the contrary, the anticipated positive effects of glutamine on the time to discharge, mortality and bacteremias have been disproved in the largest randomized controlled trial investigating glutamine supplementation in burns. An individualized approach in term of nutrients quantity and quality may proof highly valuable and needs to be validated in adequate trials. The combination of nutrition and physical exercises is another studied strategy that could improve muscle outcomes.

SUMMARY

Due to the low number of clinical trials focused on severe burn injury, most often including limited number of patients, developing new evidence-based guidelines is challenging. More high-quality trials are needed to improve the existing recommendations in the very next future.

Safety and benefits of intraoperative enteral nutrition in critically ill pediatric burn patients: A systematic review and pooled analysis

Burn injuries significantly increase a patient's metabolic demand. Adequate nutrition is essential as an adjunct to recovery and reducing morbidity and mortality. In contrast to adults, this is especially important for pediatric patients who have limited reserves and are in a period of growth. Burn patients often require multiple anesthetic procedures that are accompanied by standard perioperative fasting periods that result in substantial nutritional interruptions. Continuous intraoperative feeding has been proposed as a solution, but there is no current consensus on its role and safety, particularly in the pediatric population. Thus, the goal of this study was to examine the safety and benefits of intraoperative nutrition in critically-ill pediatric burn injured patients. A systematic review of MEDLINE, PubMed, Scopus, and Web of Science was conducted using the following terms: feeding or enteral or nutrition or fasting and adolescent or youth or pediatric or child or teen and burn or thermal injury or fire. The primary outcome was incidence of aspiration. Secondary outcomes included patient nutritional status (caloric deficit and weight), wound healing, days spent in the intensive care unit, ventilator days, pneumonia, number of surgeries, length of hospital stay, and mortality. Pooled analyses of binary outcomes were computed. Four studies consisting of 496 patients, met inclusion criteria. All studies were level IV evidence, but had high methodological quality. The median burn total body surface area (TBSA) was 43.8% (IQR 33.4-58.8%), with a median of 30% of patients having an inhalational injury. Patients underwent a median of 4.2 surgeries (IQR 1.8-7.4). Intraoperative feeding was conducted through nasoduodenal tubes. There were no aspiration events. Pooled analysis demonstrated that there were no differences in rates of aspiration, pneumonia, or wound infection (p>0.05) between patients who were intraoperatively fed and those who were not. Those fed intraoperatively had significantly more surgeries, ventilator days, longer hospital stays, but lower mortality (p<0.05). There was large heterogeneity in nutritional assessment methods. Intraoperatively fed patients had an average gain of 144.4 kcal/kg,1.7 days of exclusive enteral nutrition (vs. loss of -119.1 kcal/kg and -1.4 days), and a cumulative positive caloric balance of +2673kcal ±2147 (vs. loss of -7899kcal ±3123) compared to those with interrupted feeding. Continuous intraoperative duodenal feeding during burn surgery appears to be safe in the pediatric burn population, with no reported episodes of aspiration. Uninterrupted feeding was also associated with weight maintenance and reduced caloric deficit. It may also have a survival benefit, as continuously fed patients needed more surgeries and intensive/hospital care, but had decreased mortality.

How long are mechanically ventilated patients fasted prior to surgery? An exploratory study examining preoperative fasting practices across trauma centres

For mechanically ventilated patients undergoing surgery, interrupting enteral feeding to prevent pulmonary aspiration is common; however, there are no published preoperative fasting guidelines for these patients, resulting in fasting practices that often vary greatly between hospitals. This retrospective study described fasting practices and surgical outcomes of mechanically ventilated patients across five trauma centres. The primary exposure was hours nil per os before surgery and was stratified into short (<6h) and moderate (≥6h) fasting duration. Shared frailty models assessed the relationship between time to perioperative complication and nil per os category. Three of the five hospitals had preoperative fasting guidelines, and those most compliant required patients to be fed up until surgery. Most patients were fasted ≥6h prior to surgery and no increased risk of complication was found for patients who were fasted <6h. Future studies are needed to establish appropriate preoperative fasting thresholds for mechanically ventilated patients.

Challenges in anaesthesia and pain management for burn injuries

Burn-injured patients provide unique challenges to those providing anaesthesia and pain management. This review aims to update both the regular burn anaesthetist and the anaesthetist only occasionally involved with burn patients in emergency settings. It addresses some aspects of care that are perhaps contentious in terms of airway management, fluid resuscitation, transfusion practices and pharmacology. Recognition of pain management failures and the lack of mechanism-specific analgesics are discussed along with the opioid crisis as it relates to burns and nonpharmacological methods in the management of distressed patients.

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.

[Nutritional aspects of the management of the severely burned patient]

The nutrition of the severely burned patient is one of the pillars of his or her care, from the first few hours after the accident to rehabilitation. When properly conducted, there is a recognized beneficial effect on morbidity and even mortality.

Interrupted Nutrition Support in Patients With Burn Injuries: A Single-Centre Observational Study

Background

Enteral nutrition (EN) is essential to meet the increased metabolic requirements of burn-injured patients. However, feeds are often suspended for care. This study examines the interruptions in EN (IEN).

Objective

To determine the frequency and duration of IEN and whether these interruptions are predictable or unpredictable.

Design

This retrospective chart review of 27 adult burn patients examined age, sex, body mass index, percentage of total body surface area, length of hospital stay, predicted energy requirements from equations and indirect calorimetry, EN start time, time EN reached goal rate, and interruptions to EN.

Results

Predictable interruptions accounted for 74.5% (frequency) and 81.6% (duration) of total interruptions. The most frequent and time-consuming interruptions were perioperative period, extubation, and tests/procedures (predictable) versus high gastric residual volume, emesis/nausea, and feeding tube displacement (unpredictable).

Conclusions

Most IEN were due to predictable events. Based on these findings, compensating for predictable interruptions to meet nutritional requirements in burn patients is recommended.