Early nutrition support in the intensive care unit: a US perspective

Initial nutritional management during noninvasive ventilation and outcomes: a retrospective cohort study

Background

Patients starting noninvasive ventilation (NIV) to treat acute respiratory failure are often unable to eat and therefore remain in the fasting state or receive nutritional support. Maintaining a good nutritional status has been reported to improve patient outcomes. In the present study, our primary objective was to describe the nutritional management of patients starting first-line NIV, and our secondary objectives were to assess potential associations between nutritional management and outcomes.

Methods

Observational retrospective cohort study of a prospective database fed by 20 French intensive care units. Adult medical patients receiving NIV for more than 2 consecutive days were included and divided into four groups on the basis of nutritional support received during the first 2 days of NIV: no nutrition, enteral nutrition, parenteral nutrition only, and oral nutrition only.

Results

Of the 16,594 patients admitted during the study period, 1075 met the inclusion criteria; of these, 622 (57.9%) received no nutrition, 28 (2.6%) received enteral nutrition, 74 (6.9%) received parenteral nutrition only, and 351 (32.7%) received oral nutrition only. After adjustment for confounders, enteral nutrition (vs. no nutrition) was associated with higher 28-day mortality (adjusted HR, 2.3; 95% CI, 1.2–4.4) and invasive mechanical ventilation needs (adjusted HR, 2.1; 95% CI, 1.1–4.2), as well as with fewer ventilator-free days by day 28 (adjusted relative risk, 0.7; 95% CI, 0.5–0.9).

Conclusions

Nearly three-fifths of patients receiving NIV fasted for the first 2 days. Lack of feeding or underfeeding was not associated with mortality. The optimal route of nutrition for these patients needs to be investigated.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1867-y) contains supplementary material, which is available to authorized users.

Early enteral nutrition compared with parenteral nutrition for esophageal cancer patients after esophagectomy: a meta-analysis

Early postoperative enteral nutrition (EN) after esophagectomy in esophageal cancer patient has been reported to be correlated with a better rehabilitation than parenteral nutrition (PN). However, a robust conclusion has not been achieved. Therefore, we performed a meta-analysis to compare the postoperative EN and PN in patients with esophageal cancer undergoing esophagectomy. Three electronic databases were searched for eligible studies to be included in the meta-analysis. The summary relative risk/weighted mean difference (RR/WMD) estimates and corresponding 95% confidence interval (CI) were calculated using fixed- and random-effects models. Ten studies met the inclusion criteria. The analysis demonstrated that the early postoperative EN could significantly decrease the pulmonary complications (RR = 0.37, 95% CI = 0.22-0.62, P = 0.00, test for heterogeneity: I(2) = 0.0%, P = 0.89) and anastomotic leakage (RR = 0.46, 95% CI = 0.22-0.96, P = 0.04, test for heterogeneity: I(2) = 0.0%, P = 0.66) compared with PN. On the eighth postoperative day, the EN group had a higher levels of albumin (WMD = 1.84, 95% CI = 0.47-3.21, P = 0.01, test for heterogeneity: I(2) = 84.5%, P = 0.00) and prealbumin (WMD = 12.96, 95% CI = 3.63-22.29, P = 0.01, test for heterogeneity: I(2) = 0.0%, P = 0.63) compared with the PN group. However, there was no difference in digestive complications between these two approaches (RR = 1.30, 95% CI = 0.79-2.13, P = 0.30, test for heterogeneity: I(2) = 0.0%, P = 0.97). For patients with esophageal cancer following esophagectomy, the early postoperative EN support could decrease the morbidity of severe complications, such as pulmonary complications and anastomotic leakage, and maintain patients at a better nutritional status than parenteral nutrion support.

Cilostazol administration with combination enteral and parenteral nutrition therapy remarkably improves outcome after subarachnoid hemorrhage

OBJECTIVE

In order to prevent cerebral vasospasm (VS) following aneurysmal subarachnoid hemorrhage (SAH), we introduced combined enteral nutrition (EN) and parenteral nutrition (PN) with oral cilostazol administration to the postoperative patient after SAH and investigated the effect on VS.

METHODS

After aneurysmal SAH, 130 postoperative patients were enrolled in this study between April 2008 and March 2012. The patients enrolled before April 2010 were treated by conventional therapy (control group). The patients enrolled after April 2010 were administrated cilostazol 200 mg/day and received EN and PN simultaneously (combined group).

RESULTS

The combined group consisted of 62 patients and the control group of 68 patients. Angiographic VS occurred in 33.9 % (n = 21) of the combined group and in 51.5 % (n = 35) of the control group (p = 0.051, Fisher exact test). The incidence of symptomatic VS was significantly lower in the combined group (p = 0.001). The incidence of new cerebral infarctions was also significantly lower in the combined group (p = 0.0006). Clinical outcome at discharge was also significantly better in the combined group than in control group (p = 0.031).

CONCLUSIONS

Cilostazol administration with combination EN and PN is remarkably effective in preventing cerebral VS after aneurysmal SAH.

Is enteral feeding tolerated during therapeutic hypothermia?

OBJECTIVE

To determine whether patients undergoing therapeutic hypothermia following cardiac arrest tolerate early enteral nutrition.

METHODS

We undertook a single-centre longitudinal cohort analysis of the tolerance of enteral feeding by 55 patients treated with therapeutic hypothermia following resuscitation from cardiac arrest. The observation period was divided into three phases: (1) 24h at target temperature (32-34 °C); (2) 24h rewarming to 36.5 °C; and (3) 24h maintained at a core temperature below 37.5 °C.

RESULTS

During period 1, patients tolerated a median of 72% (interquartile range (IQR) 68.7%; range 31.3-100%) of administered feed. During period 2 (rewarming phase), a median of 95% (IQR 66.2%; range 33.77-100%) of administered feed was tolerated. During period 3 (normothermia) a median of 100% (IQR 4.75%; range 95.25-100%) of administered feed was tolerated. The highest incidence of vomiting or regurgitation of feed (19% of patients) occurred between 24 and 48 h of therapy.

CONCLUSIONS

Patients undergoing therapeutic hypothermia following cardiac arrest may be able to tolerate a substantial proportion of their daily nutritional requirements. It is possible that routine use of prokinetic drugs during this period may increase the success of feed delivery enterally and this could usefully be explored.

[Guidelines for specialized nutritional and metabolic support in the critically-ill patient. Update. Consensus of the Spanish Society of Intensive Care Medicine and Coronary Units-Spanish Society of Parenteral and Enteral Nutrition (SEMICYUC-SENPE): acute renal failure]

Nutritional support in acute renal failure must take into account the patient's catabolism and the treatment of the renal failure. Hypermetabolic failure is common in these patients, requiring continuous renal replacement therapy or daily hemodialysis. In patients with normal catabolism (urea nitrogen below 10 g/day) and preserved diuresis, conservative treatment can be attempted. In these patients, relatively hypoproteic nutritional support is essential, using proteins with high biological value and limiting fluid and electrolyte intake according to the patient's individual requirements. Micronutrient intake should be adjusted, the only buffering agent used being bicarbonate. Limitations on fluid, electrolyte and nitrogen intake no longer apply when extrarenal clearance techniques are used but intake of these substances should be modified according to the type of clearance. Depending on their hemofiltration flow, continuous renal replacement systems require high daily nitrogen intake, which can sometimes reach 2.5 g protein/kg. The amount of volume replacement can induce energy overload and therefore the use of glucose-free replacement fluids and glucose-free dialysis or a glucose concentration of 1 g/L, with bicarbonate as a buffer, is recommended. Monitoring of electrolyte levels (especially those of phosphorus, potassium and magnesium) and of micronutrients is essential and administration of these substances should be individually-tailored.

Perioperative nutritional support: immunonutrition, probiotics, and anabolic steroids

Nutritional support in surgical patients has evolved from simple provision of adequate calories to retard loss of lean body mass to the provision of specific nutrients in an attempt to manipulate metabolic and immune responses. Although still limited, the current understanding of this complex subject indicates that the type, route, amount, and composition of nutritional support provided to patients can affect their outcome. Further studies are, however, needed to better characterize the exact nutritional support that is most beneficial for a specific disease state and a specific patient.

Post-PEG feeding time: a web based national survey amongst gastroenterologists

BACKGROUND

Literature suggests early post-percutaneous endoscopic gastrostomy (PEG) feeding is as safe as delayed feeding. No consensus exists regarding feeding initiation after PEG placement. We performed a national survey to assess current practice regarding feeding initiation after PEG placement as well as clinical and practitioner based factors associated with early or delayed feeding.

METHODS

A survey assessing feeding initiation in general ward and intensive care unit patients, current literature knowledge, motility agent use, number of PEG placed per year, along with physician demographics was emailed to 5256 gastroenterologists. Statistical analysis was done using SAS software (V.9).

RESULTS

28% of gastroenterologists responded. Amongst respondents, 59% were private consultants, 25% academic physicians and 16% trainees. Private gastroenterologists initiated feeding earlier (≤12 h) compared to academic gastroenterologists in general ward and intensive care unit patients (p<0.0001). Amongst respondents, 41% of physicians were aware of current literature on post-PEG feeding times. Physicians aware of current literature started feeding earlier (<12h) compared to those not aware in general ward and intensive care unit patients (p=0.0002). Male physicians instituted feeding earlier than females (p<0.0001).

CONCLUSIONS

Feeding initiation after PEG placement varies amongst gastroenterologists. Further studies are required to explore obstacles in standardizing post-PEG feeding practices.

Computer-assisted glucose regulation during rapid step-wise increases of parenteral nutrition in critically ill patients: a proof of concept study

BACKGROUND

Early delivery of calories is important in critically ill patients, and the administration of parenteral nutrition (PN) is sometimes required to achieve this goal. However, PN can induce acute hyperglycemia, which is associated with adverse outcome. We hypothesized that initiation of PN using a rapid "step-up" approach, coupled with a computerized insulin-dosing protocol, would result in a desirable caloric intake within 24 hours without causing hyperglycemia.

METHODS

In our surgical intensive care unit (ICU), glucose is regulated by a nurse-centered computerized glucose regulation program. When adequate enteral feeding was not possible, PN was initiated according to a simple step-up rule at an infusion rate of 10 mL/h (approximately 10 kcal/h) and subsequently increased by steps of 10 mL/h every 4 hours, provided glucose was <10 mmol/L, until the target caloric intake (1 kcal/kg/h) was reached. All glucose levels and insulin doses were collected during the step-up period and for 24 hours after achieving target feeding.

RESULTS

In all 23 consecutive patients requiring PN, mean intake was 1 kcal/kg/h within 24 hours. Of the 280 glucose samples during the 48-hour study period, mean ± standard deviation glucose level was 7.4 ± 1.4 mmol/L. Only 4.5% of glucose measurements during the step-up period were transiently ≥10 mmol/L. After initiating PN, the insulin requirement rose from 1.1 ± 1.5 units/h to 2.9 ± 2.5 units/h (P < .001).

CONCLUSIONS

This proof of concept study shows that rapid initiation of PN using a step-up approach coupled with computerized glucose control resulted in adequate caloric intake within 24 hours while maintaining adequate glycemic control.

Nutritional support for critically ill patients: does duration correlate with mortality?

BACKGROUND

Few investigations have correlated long-term nutritional support (NS) with outcome in the intensive care unit, in comparison with NS for shorter periods.

OBJECTIVE

In a retrospective protocol, duration of enteral and/or parenteral nutrition was analyzed in the light of severity of illness, targeting hospital mortality.

RESULTS

Seriously ill patients (n = 100), nearly all (94/100) receiving enteral nutrition (51/100), parenteral nutrition (22/100), or both (21/100), were investigated. Mean age ± SD was 60.0 ± 19.5 years (54.0% males), 56.0% were in the trauma or surgery diagnostic category, Mean Acute Physiologic and Chronic Health Evaluation II ± SD was 14.2 ± 6.7, mechanical ventilation was necessary in 41.0%, and hospital mortality was 14.0%. Nutritional support of any modality administered for 18 days or less (mean ± SD, 4.3 ± 3.6 days) was associated with favorable survival rate, whereas for longer periods (mean ± SD, 48.5 ± 29.4 days), mortality substantially increased (7.7% vs 50.0%, P = .004). Results were confirmed when long-term patients were propensity matched regarding age, Acute Physiologic and Chronic Health Evaluation II, Glasgow scale, and mechanical ventilation (6.3% vs 50.0%, P = 04).

CONCLUSIONS

Nutritional support of more than 18 days was associated with higher mortality. This finding persisted after adjustment for major risk factors, in agreement with the hypothesis that prolonged impossibility of oral alimentation is a marker of mortality in the intensive care unit setting.

A retrospective study about the influence of early nutritional support on mortality and nosocomial infection in the critical care setting

BACKGROUND & AIMS

To determine whether early nutritional support reduces mortality and the incidence of nosocomial infection, in critically ill patients in the current practice.

METHODS

A retrospective observational study was conducted in all critically ill patients who had been prescribed nutritional support, throughout one year, in an Intensive Care Unit. The time to start and the route of delivery of nutritional support were determined by the attending clinician's assessment of gastrointestinal function and hemodynamic stability. Age, gender, severity of illness, start time and route of nutritional support, prescribed and delivered daily caloric intake for the first 7 days, whether they were a medical or surgical patient, length of stay in ICU, incidence rate of nosocomial infections and ICU mortality were recorded. Patients were classified according to whether or not they received nutritional support within 48 h of their admission to ICU and Binary Logistic Regression was performed to assess the effect of early nutritional support on ICU mortality and ICU nosocomial infections after controlling for confounders.

RESULTS

Ninety-two consecutive patients were included in the study. Start time of nutritional support showed a mean of 3.1 ± 1.9 days. Patients in the early nutritional support group had a lower ICU mortality in an unadjusted analysis (20% vs. 40.4%, p = 0.033). Early nutritional support was found to be an independent predictor of mortality in the regression analysis model (OR 0,28; 95% confidence interval, 0.09 to 0,84; p = 0.023). Our study did not demonstrate any association between early nutritional support and the incidence of nosocomial infection (OR 0.77; 95%. confidence interval, 0.26 to 2,24; p = 0.63), which was related to the route of nutritional support and the caloric intake. The delayed nutritional support group showed a longer length of stay and nosocomial infections than the early group, although these differences were not statistically significant.

CONCLUSIONS

Our study shows that early nutrition support reduces ICU mortality in critically ill patients, although it does not demonstrate any influence over nosocomial infection in the current practice in intensive care.

The evolutionary role of nutrition and metabolic support in critical illness

Maintenance of nutritional status is particularly challenging during critical illness. There is a common perception of a race against the clock to adequately feed the patient to prevent or minimize the sometimes catastrophic muscle wasting and general catabolic state that can result in the patient's deterioration. However, the course of critical illness may be separated into 3 phases, each with highly differing metabolic needs. The initial phase, in which the body attempts to fight the acute insult, is generally hypermetabolic. When the body fails to overcome the insult, it enters into a second phase, which is akin to hibernation. This stage is characterized by a functional metabolic shutdown triggered either by a lack of adequate energy supply or perhaps by the direct switching off of metabolism to spare excess use of a dwindling substrate and energy resource. Those strong enough to survive this phase enter into a period of recovery during which appetite returns, anabolism recommences, and organ function is restored. Nutrition should perhaps closely follow these nonlinear requirements, so as to avoid deleterious under- or overnutrition during the appropriate phase. This approach fits a teleologic argument that enabled many sick people to survive well before the advent of modern medicine and explains why catabolism still occurs despite adequate feeding.

An Update on Nutrition Support in the Critically Ill

Nutrition support in the critically ill patient has shifted from adjunctive toward fundamental therapy with the publication of high-grade evidence. Early enteral nutrition (EN) is recommended because it is associated with decreased infectious complications and use of EN is associated with decreased mortality and infections compared with parenteral nutrition (PN). EN is not without risks, such as diarrhea or aspiration, but use of prokinetic agents, head of bed elevation, and use of feeding protocols can maximize benefits and minimize risks. Although recently high-grade evidence on nutrition support in the critically ill population has been published, many controversies still exist. In obese patients, use of hypocaloric feedings with increased protein has been demonstrated to promote weight loss and improved glucose management. In nonobese patients, small studies have demonstrated that providing more than 70% or less than 30% of goal caloric intake may be associated with worse outcomes, but more studies are needed. Additional research is also needed to conclude whether withholding intravenous fat emulsions for the first 7 to 10 days of PN reduces infectious complications. Finally, more high-quality studies are needed to define the role of immune-enhancing nutrients such as arginine, glutamine, omega-3 fatty acids, zinc, and selenium.

Intensive metabolic support: evolution and revolution

OBJECTIVE

To describe a new aspect of critical care termed intensive metabolic support.

METHODS

We performed a MEDLINE search of the English-language literature published between 1995 and 2008 for studies regarding the metabolic stages of critical illness, intensive insulin treatment, and intensive metabolic support in the intensive care unit, and we summarize the clinical data.

RESULTS

Intensive metabolic support is a 3-component model involving metabolic control and intensive insulin therapy, early nutrition support, and nutritional pharmacology aimed at preventing allostatic overload and the development of chronic critical illness. To improve clinical outcome and prevent mortality, intensive metabolic support should start on arrival to the intensive care unit and should end only when patients are in the recovery phase of their illness.

CONCLUSIONS

Intensive metabolic support should be an essential part of the daily treatment strategy in critical care medicine. This will involve a newfound and extensive collaboration between the endocrinologist and the intensivist. We call for well-designed future studies involving implementation of this protocol to decrease the burden of chronic critical illness.

Impact of new technologies on metabolic care in the intensive care unit

PURPOSE OF REVIEW

Technological innovations in the ICU have lead to extraordinary advances in modern critical care. Renal replacement therapy (RRT) innovations and ventricular assist devices (VAD) are now becoming common interventions in the ICU environment. The purpose of this article is to describe the impact of RRT and VAD on critical care medicine with particular reference to metabolic care.

RECENT FINDINGS

Continuous venovenous hemofiltration and slow low efficient daily dialysis are effective modalities of RRT in hemodynamically unstable patients. These continuous forms of RRT can result in accentuated protein and nutrient losses but also provide an opportunity for intradialytic parenteral nutrition support. VAD patients typically have cardiac cachexia and develop chronic critical illness syndrome. Intensive metabolic support, incorporating trophic, concentrated, semielemental enteral nutrition, supplemental parenteral nutrition, and intensive insulin therapy is a rational strategy to implement in VAD patients. Unfortunately, there is insufficient evidence at this time to support the routine use of these nutritional interventions with RRT and VAD.

SUMMARY

Patients requiring RRT or VAD are at high nutritional risk, which negatively affects ICU outcome. Prompt nutritional risk assessment and early optimization of metabolic care is crucial in this patient population.

Special commentary: a call for intensive metabolic support

PURPOSE OF REVIEW

This special commentary addresses recent clinical reviews regarding appropriate nutrition and metabolic support in the critical care setting.

RECENT FINDINGS

There are divergent approaches between North America and Europe for the use of early nutrition support and combined enteral nutrition and parenteral nutrition support possibly due to the commercial availability of specific parenteral nutrients. The advent of intensive insulin therapy has changed the landscape of metabolic support in the intensive care unit, and previous notions about infective risk of parenteral nutrition will need to be re-addressed. Patients with brain failure may benefit from an intensive insulin therapy with a blood glucose target that is higher than that used in patients without brain failure. Patients with heart failure may benefit from the addition of nutritional pharmacology that targets proximate oxidative pathophysiological pathways. Intradialytic parenteral nutrition may be viewed as another form of supplemental parenteral nutrition when enteral nutrition is insufficient in patients on hemodialysis in the intensive care unit.

SUMMARY

It is proposed that intensive metabolic support be routinely implemented in the intensive care unit based on the following steps: intensive insulin therapy with an appropriate blood glucose target, nutrition risk assessment, early and if needed combined enteral nutrition and parenteral nutrition to target 20-25 kcal/kg/day and 1.2-1.5 g protein/kg/day, and nutritional and metabolic monitoring.