Improving Nutrition in Mechanically Ventilated Patients

BACKGROUND

Although proper diet has been found to play an important role in patient outcomes, studies have shown that intensive care unit patients often receive inadequate nutrition. Moreover, it has been found that critically ill patients who are mechanically ventilated regularly receive even less nutrition. Inadequate nutrition has been associated with impaired immune response, increased susceptibility to infection, poor wound healing, and neuromuscular impairment. These factors lead to prolonged dependence on ventilators, protracted length of stay, and increased morbidity and mortality. This study investigates the use of an enteral nutrition (EN) protocol and its ability to prompt earlier initiation of feedings and more complete nutrition in mechanically ventilated patients to minimize such complications.

METHODS

In a sample of 51 mechanically ventilated patients admitted to an intensive care unit, percentage of prescribed calories received and percentage of feedings initiated with 24-48 hours of intubation were calculated before and after the initiation of an EN protocol.

RESULTS

In the postintervention group (n = 18), 83.3% received EN with the first 24-48 hours after intubation, compared with 54.5% in the preintervention group (n = 33). In the postintervention group, 77.8% received at least 60% of their prescribed feeding goal compared with 63.6% of the preintervention group.

CONCLUSION

Findings show that the use of an EN protocol when caring for mechanically ventilated patients leads to earlier initiation of feedings as well as more complete nutrition.

Hypocaloric compared with eucaloric nutritional support and its effect on infection rates in a surgical intensive care unit: a randomized controlled trial

BACKGROUND

Proper caloric intake goals in critically ill surgical patients are unclear. It is possible that overnutrition can lead to hyperglycemia and an increased risk of infection.

OBJECTIVE

This study was conducted to determine whether surgical infection outcomes in the intensive care unit (ICU) could be improved with the use of hypocaloric nutritional support.

DESIGN

Eighty-three critically ill patients were randomly allocated to receive either the standard calculated daily caloric requirement of 25-30 kcal · kg(-1) · d(-1) (eucaloric) or 50% of that value (hypocaloric) via enteral tube feeds or parenteral nutrition, with an equal protein allocation in each group (1.5 g · kg(-1) · d(-1)).

RESULTS

There were 82 infections in the hypocaloric group and 66 in the eucaloric group, with no significant difference in the mean (± SE) number of infections per patient (2.0 ± 0.6 and 1.6 ± 0.2, respectively; P = 0.50), percentage of patients acquiring infection [70.7% (29 of 41) and 76.2% (32 of 42), respectively; P = 0.57], mean ICU length of stay (16.7 ± 2.7 and 13.5 ± 1.1 d, respectively; P = 0.28), mean hospital length of stay (35.2 ± 4.9 and 31.0 ± 2.5 d, respectively; P = 0.45), mean 0600 glucose concentration (132 ± 2.9 and 135 ± 3.1 mg/dL, respectively; P = 0.63), or number of mortalities [3 (7.3%) and 4 (9.5%), respectively; P = 0.72]. Further analyses revealed no differences when analyzed by sex, admission diagnosis, site of infection, or causative organism.

CONCLUSIONS

Among critically ill surgical patients, caloric provision across a wide acceptable range does not appear to be associated with major outcomes, including infectious complications. The optimum target for caloric provision remains elusive.

A double-blind, randomized clinical trial comparing soybean oil-based versus olive oil-based lipid emulsions in adult medical-surgical intensive care unit patients requiring parenteral nutrition

OBJECTIVE

Parenteral nutrition has been associated with metabolic and infectious complications in intensive care unit patients. The underlying mechanism for the high risk of complications is not known but may relate to the proinflammatory effects of soybean oil-based lipid emulsions, the only Food and Drug Administration-approved lipid formulation for clinical use.

DESIGN

Prospective, double-blind, randomized, controlled trial.

SETTING

Medical-surgical intensive care units from a major urban teaching hospital and a tertiary referral university hospital.

PATIENTS

Adult medical-surgical intensive care unit patients.

INTERVENTION

Parenteral nutrition containing soybean oil-based (Intralipid) or olive oil-based (ClinOleic) lipid emulsions.

MEASUREMENTS

Differences in hospital clinical outcomes (nosocomial infections and noninfectious complications), hospital length of stay, glycemic control, inflammatory and oxidative stress markers, and granulocyte and monocyte functions between study groups.

RESULTS

A total of 100 patients were randomized to either soybean oil-based parenteral nutrition or olive oil-based parenteral nutrition for up to 28 days. A total of 49 patients received soybean oil-based parenteral nutrition (age 51 ± 15 yrs, body mass index 27 ± 6 kg/m2, and Acute Physiology and Chronic Health Evaluation II score 15.5 ± 7 [±SD]), and a total of 51 patients received olive oil-based lipid emulsion in parenteral nutrition (age 46 ± 19 yrs, body mass index 27 ± 8 kg/m2, and Acute Physiology and Chronic Health Evaluation II score 15.1 ± 6 [±SD]) for a mean duration of 12.9 ± 8 days. The mean hospital blood glucose concentration during parenteral nutrition was 129 ± 14 mg/dL, without differences between groups. Patients treated with soybean oil-based and olive oil-based parenteral nutrition had a similar length of stay (47 ± 47 days and 41 ± 36 days, p = .49), mortality (16.3% and 9.8%, p = .38), nosocomial infections (43% vs. 57%, p = .16), and acute renal failure (26% vs. 18%, p = .34). In addition, there were no differences in inflammatory and oxidative stress markers or in granulocyte and monocyte functions between groups.

CONCLUSION

The administration of parenteral nutrition containing soybean oil-based and olive oil-based lipid emulsion resulted in similar rates of infectious and noninfectious complications and no differences in glycemic control, inflammatory and oxidative stress markers, and immune function in critically ill adults.

Grasping the nutritional situation: a grounded theory study of patients' experiences in intensive care

AIM AND OBJECTIVES

The aim of this study was to provide a theoretical understanding of nutritional experiences for patients with enteral nutrition (EN) during their stay in the intensive care unit (ICU).

BACKGROUND

It is well known that EN can result in underfeeding for patients in ICUs. How the patients experience their nutritional care during their stay in the ICU remains somewhat unclear.

DESIGN AND METHODS

In this study, a grounded theory approach was chosen to conduct and analyse 14 interviews with patients and 21 observations of nutritional care during the patients' stay in an ICU.

FINDINGS

The core category 'grasping nutrition during the recovery process' was reflected in, and related to, the categories 'facing nutritional changes', 'making sense of the nutritional situation' and 'being involved with nutritional care'. While grasping the nutrition, the patients were emotionally shifting between worry, fear and failure, and relief and hope. Turning points were having the appetite back, getting rid of the feeding tube and regaining a functioning gut.

CONCLUSIONS

The patients' views of nutritional care during their stay in the ICU may contribute to understanding of how patients make sense of their nutritional changes and how they are involved in their nutritional care. This study shows that grasping the nutrition can be a way to regain some control in a situation where the patients are highly dependent on professional care. Further research is needed to develop this substantive theory in other intensive care settings to support patients' nutritional journey in intensive care.

RELEVANCE TO CLINICAL PRACTICE

Nurses can promote patients' abilities to grasp their nutritional situation during their recovery process. There is a need to focus not only on the patients' physical needs but also on their emotional and social needs.

Factors predicting adherence to the Canadian Clinical Practice Guidelines for nutrition support in mechanically ventilated, critically ill adult patients

PURPOSE

The aim of this study was to determine factors that are associated with adherence to the Canadian nutrition support clinical practice guidelines (CPGs).

MATERIALS AND METHODS

We conducted a secondary analysis of data from a prospective observational cohort study of nutrition support practices in 58 intensive care units (ICUs) across Canada, grouped into 50 clusters. Adequacy of enteral nutrition (EN) (energy received from EN / energy prescribed by the dietitian x 100), was used as a marker of adherence to the guidelines. We applied hierarchical modeling techniques to examine the impact of various hospital, ICU, and patient factors on EN adequacy.

RESULTS

The overall average EN adequacy was 51.3% (SE, 1.8%). In a multiple regression analysis, after adjusting for varying days of observation, hospital type (academic 54.3% vs community 45.2%, P < .001), admission category of the patient (medical 60.2% vs surgical 39.2%, P < .001), and sex of the patient (male 46.5% vs female 52.8%, P < .001) were found to be significant predictors of EN adequacy and adherence to the Canadian nutrition support CPGs.

CONCLUSIONS

Specific hospital, ICU, and patient characteristics influence adherence to the Canadian nutrition support CPGs. Further research is required to illuminate the mechanisms by which female and surgical patients and community hospitals lead to lower guideline adherence.

Preliminary Evidence for a Medical Nutrition Therapy Protocol: Enteral Feedings for Critically Ill Patients

The objective of this study was to evaluate the evidence behind specific but common patient care decisions in support of enteral feedings for patients admitted to intensive care units. Six specific questions were developed and refined to address clinical outcomes specific to clinical practice decisions pertinent to enteral feeding of critically ill patients. The data sources consisted of an intensive literature review from five databases, using standardized search terms. Randomized controlled clinical trials, meta-analyses, consensus statements, reviews, US Food and Drug Administration alerts, and case reports were selected for study. Research reports were abstracted in detail and evaluated for research quality using the criteria developed by the American Dietetic Association. Consensus statements regarding the influence of specific enteral feeding methods on key clinical outcomes (ie, infectious complications, cost, length of hospital stay, and mortality) were developed and graded based on the quality of the available evidence. The data support the use of enteral over parenteral nutrition to reduce infectious complications and cost, and the initiation of enteral feedings within 24 to 48 hours of injury or admission to an intensive care unit to reduce infectious complications and length of hospital stay in head injury and trauma patients. Postpyloric tube placement is associated with reduced gastric residual volume and reflux, but adequately powered trials are not available to support prevention of aspiration pneumonia. Acceptance of gastric residual volumes of up to 250 mL may increase volume of formula delivered. Promotility agents are associated with reduced gastric residual volume. Feeding patients in the semirecumbent rather than supine position is associated with reduced aspiration pneumonia and pharyngoesophageal formula reflux. Actual delivery of 14 to 18 kcal/kg/day or 60% to 70% of goal is associated with improved outcomes, whereas greater intake may not be in some populations. Blue food coloring should not be used with enteral feedings due to its limited sensitivity for aspiration and some risk of mortality. Well-designed, adequately powered, randomized controlled clinical trials are needed to evaluate any benefit of tube tip position on aspiration pneumonia or mortality, and of early enteral feedings on mortality.

Nutrition of the critically ill patient and effects of implementing a nutritional support algorithm in ICU

AIM

To test whether a feeding algorithm could improve the nutritional support of intensive care patients.

BACKGROUND

Numerous factors may impede delivery of both enteral and parenteral nutrition to patients in the intensive care unit. Often there is a discrepancy between what is prescribed and actual delivery of nutrients. The purpose of this study was to test the effect of a nutritional support algorithm in an intensive care unit mainly by using the enteral route and if necessary by combining enteral and parenteral nutrition.

METHODS

In this prospective study, nutritional data were collected from routinely fed critically ill patients (controls, n=21) during the first three days following admission to the intensive care unit. A nutritional support algorithm was then implemented and nutritional data were collected from critically ill patients who participated in this intervention (intervention group, n=21). Data collected included the total amount of calories prescribed vs. received, onset of delivery of enteral nutrition, enteral vs. parenteral nutrition, and the use and size of enteral feeding tubes.

RESULTS

Patients in the intervention group were both prescribed and actually received significantly larger amounts of nutrients than patients in the control group. They also received a larger proportion of their nutrients in the form of enteral nutrition. In addition, the nutritional support algorithm led to greater consistency in nursing practices with respect to aspiration of gastric content and rate of increment in enteral feeding.

CONCLUSION

The study confirms that a nutritional support algorithm improved the delivery of nutrients to critically ill patients. The algorithm was most effective with respect to the delivery of enteral nutrition. The effect was primarily because of early and more rapid increment in the delivery of enteral nutrition administered by nurses based on improved physician orders. The combination of enteral and parenteral nutrition may contribute to meeting adequate nutritional requirements.

RELEVANCE TO CLINICAL PRACTICE

By using a nutritional algorithm focused on enteral nutrition, but including parenteral nutrition as a supplement, it is possible to improve the delivery of clinical nutrition in the intensive care unit patients.

Does enteral nutrition compared to parenteral nutrition result in better outcomes in critically ill adult patients? A systematic review of the literature

OBJECTIVE

Nutritional support is part of the standard of care for the critically ill adult patient. In the average patient in the intensive care unit who has no contraindications to enteral nutrition (EN) or parenteral nutrition (PN), the choice of route for nutritional support may be influenced by several factors. Because EN and PN are associated with risks and benefits, we systematically reviewed and critically appraised the literature to compare EN with PN the critically ill patient.

METHODS

We searched computerized bibliographic databases, personal files, and relevant reference lists to identify potentially eligible studies. Only randomized clinical trials that compared EN with PN in critically ill patients with respect to clinically important outcomes were included in this review. In an independent fashion, relevant data on the methodology and outcomes of primary studies were abstracted in duplicate. The studies were subsequently aggregated statistically.

RESULTS

There were 13 studies that met the inclusion criteria and, hence, were included in our meta-analysis. The use of EN as opposed to PN was associated with a significant decrease in infectious complications (relative risk = 0.64, 95% confidence interval = 0.47 to 0.87, P = 0.004) but not with any difference in mortality rate (relative risk = 1.08, 95% confidence interval = 0.70 to 1.65, P = 0.7). There was no difference in the number of days on a ventilator or length of stay in the hospital between groups receiving EN or PN (Standardized Mean Difference [SMD] = 0.07, 95% confidence interval = -0.2 to 0.33, P = 0.6). PN was associated with a higher incidence of hyperglycemia. Data that compared days on a ventilator and the development of diarrhea in patients who received EN versus PN were inconclusive. In the EN and PN groups, complications with enteral and parenteral access were seen. Four studies documented cost savings with EN as opposed to PN.

CONCLUSION

The use of EN as opposed to PN results in an important decrease in the incidence of infectious complications in the critically ill and may be less costly. EN should be the first choice for nutritional support in the critically ill.

Outcomes in critically ill patients before and after the implementation of an evidence-based nutritional management protocol

OBJECTIVE

To determine whether the implementation of a nutritional management protocol in the ICU leads to the increased use of enteral nutrition, earlier feeding, and improved clinical outcomes in patients.

DESIGN

Prospective evaluation of critically ill patients before and after the introduction of an evidence-based guideline for providing nutritional support in the ICU.

SETTING

The medical-surgical ICUs of two teaching hospitals.

PATIENTS

Two hundred critically ill adult patients who remained npo > 48 h after their admission to the ICU. One hundred patients were enrolled into the preimplementation group, and 100 patients were enrolled in the postimplementation group.

INTERVENTION

Implementation of an evidence-based ICU nutritional management protocol.

MEASUREMENT AND RESULTS

Nutritional outcome measures included the number of patients who received enteral nutrition, the time to initiate nutritional support, and the percent caloric target administered on day 4 of nutritional support. Clinical outcomes included the duration of mechanical ventilation, ICU and in-hospital length of stay (LOS), and in-hospital mortality rates. Patients in the postimplementation group were fed more frequently via the enteral route (78% vs 68%, respectively; p = 0.08), and this difference was statistically significant after adjusting for severity of illness, baseline nutritional status, and other factors (odds ratio, 2.4; 95% confidence interval [CI], 1.2 to 5.0; p = 0.009). The time to feeding and the caloric intake on day 4 of nutritional support were not different between the groups. The mean (+/- SD) duration of mechanical ventilation was shorter in the postimplementation group (17.9 +/- 31.3 vs 11.2 +/- 19.5 days, respectively; p = 0.11), and this difference was statistically significant after adjusting for age, gender, severity of illness, type of admission, baseline nutritional status, and type of nutritional support (p = 0.03). There was no difference in ICU or hospital LOS between the two groups. The risk of death was 56% lower in patients who received enteral nutrition (hazard ratio, 0.44; 95% CI, 0.24 to 0.80; p = 0.007).

CONCLUSION

An evidence-based nutritional management protocol increased the likelihood that ICU patients would receive enteral nutrition, and shortened their duration of mechanical ventilation. Enteral nutrition was associated with a reduced risk of death in those patients studied.

Nutritional intake in the critically ill: Improving practice through research

Enteral feeding is the preferred method of nutritional support in the critically ill; however, evidence suggests that many critically ill patients do not meet their nutritional goals. The implementation of enteral feeding protocols has improved nutritional delivery, although protocols can be widely variable. Similarly, enteral feeding related nursing practice is also inconsistent within and between intensive care units (ICUs). These variations in enteral feeding practice can be linked to the shortage of reliable and valid research into the many issues associated with the effective delivery of enteral nutrition. In the absence of a strong research tradition and practice, rituals are embraced and rarely challenged, further contributing to the wide variations in enteral feeding practice. Of particular importance are practice issues related to the commencement of enteral feeding and the assessment of feeding tolerance. This article seeks to review the literature related to commencing enteral feeding, with particular reference to the suitability of enteral nutrition, methods of enteral feeding and adjustment of enteral feeding rates. Issues relating to feeding intolerance, including the assessment of gastric residual volume and the development of diarrhoea, will also be explored.

Parenteral nutrition in the critically-ill patient: more harm than good?

While many studies have reported that providing parenteral nutrition (PN) can change nutritional outcomes, there are limited data that demonstrate that PN influences clinically-important end points in critically-ill patients. The purpose of the present paper is to systematically review and critically appraise the literature to examine the relationship between PN and morbidity and mortality in the critically-ill patient. Studies comparing enteral nutrition (EN) with PN and studies comparing PN with no PN were reviewed. The results suggest that EN is associated with reduced infectious complications in some critically-ill subgroups. PN, on the other hand, is associated with increased morbidity and mortality in critically-ill patients. When nutritional support is indicated, EN should be used preferentially over PN. Further studies are needed to define the optimal timing and composition of PN in patients not tolerating sufficient EN. Strategies to optimize EN delivery and minimize PN utilization in critically-ill patients are indicated.

Enteral nutrition access devices

During the past decade a concerted effort has been made to use enteral nutrition instead of parenteral nutrition for hospitalized patients. Enteral nutrition has major advantages over parenteral nutrition in terms of cost and fewer serious complications. A clinician interested in initiating enteral nutrition may be limited by a lack of familiarity with the variety of options for enteral access and the difficulty of choosing among them. This paper reviews the different enteral access routes and devices available to the clinician.

Nutritional support in the critically ill patients. A critical review of the evidence

Providing nutritional support has become a standard component of managing critically ill patients. While many studies have documented that providing nutritional support can change nutritional outcomes (e.g., amino acid profile, weight gain, nitrogen balance), data are lacking that demonstrate that nutrition actually influences clinically importance endpoints. This article systematically reviews and critically appraises the literature, examining the relationship between nutritional support and infectious morbidity and mortality in the critically ill patient. In addition, evidence-based recommendations are made.

Effect of Acid Feeds on Feeding System Contamination

BACKGROUND AND OBJECTIVE

Bacterial contamination of the enteral nutrition delivery system (FS) has been well described. Case reports and prospective cohort studies suggest that bacterial contamination is a cause of morbidity and mortality in the critically ill patient. Because bacterial growth and replication is pH dependent, we hypothesized that acidified enteral feedings would lower incidence of bacterial contamination of the FS and potentially infectious morbidity and mortality of critically ill patients. Our objective was to evaluate the effect of acidified enteral feedings on bacterial growth in the FS and subsequent gastric and tracheal bacterial growth.

DESIGN

Randomized, double-blind, placebo-controlled, multicenter study.

SETTING

Eight mixed intensive care units at tertiary care hospitals.

PATIENTS

We recruited mechanically ventilated critically ill patients expected to remain ventilated ≥48 hours. We excluded patients with overt gastrointestinal bleeding, persistent acidemia, and renal failure requiring dialysis. We enrolled 120 patients: women, 38%; age, 57.6 ± 19.3 years, and mean APACHE II score, 21.6 ± 7.6.

INTERVENTIONS

Vital High Nitrogen (Abbott Laboratories, Ross Products Division, Columbus, OH) was used as the standard feeding formula for the control group. Hydrochloric acid was added to achieve a pH to 3.5 in the experimental group.

MAIN OUTCOME MEASURES

Microbial growth in the FS, stomach, and trachea.

RESULTS

Compared with patients in the control group, patients who received acid feedings were less likely to have potentially pathogenic microorganisms in their FSs (19% versus 80% of patients [p ≤ .001] and 0.1 versus 0.8 organisms per specimen [p ≤ .001]). There were 151 organisms that were cultured in two or more sites. Of the 146 organisms cultured from the stomach, 22 (15%) were first cultured in the feeding system and 32 (22%) were cultured simultaneously in the feeding system and the stomach. Of the 58 organisms cultured in the trachea, 19 (33%) were first cultured in the feeding system and 6 (10%) were cultured simultaneously in the feeding system and the trachea.

CONCLUSIONS

The feeding system is a frequent source of gastric and tracheal contamination. Acidified enteral feedings reduces contamination of the feeding system and therefore may have an impact on subsequent colonization and infection. Larger studies of acidified enteral feedings are needed to examine their effect on infectious morbidity and mortality.

Nutritional assessment in the critically ill

Essentially, there have not been any outstanding recent developments in nutritional assessment techniques. However, it would appear that the acceptance that there is no absolute gold standard for nutritional assessment has led to the development of disease specific and clinically relevant subjective global type-assessments, which are user-friendly and effective tools. The further development of dual frequency bioelectrical impedance models may allow for greater accuracy in the differentiation of alterations in body composition.

Nasal bridle revisited: an improvement in the technique to prevent unintentional removal of small-bore nasoenteric feeding tubes

OBJECTIVE

To demonstrate the efficacy and safety of an updated version of the nasal "bridle," which is used to prevent the accidental removal of small-bore nasoenteric feeding tubes.

DESIGN

A descriptive study.

SETTING

Surgical intensive care unit in a tertiary care hospital.

PATIENTS

Twenty-six critically ill patients without nasotracheal tubes or facial trauma or fractures who received enteral nutrition and either had removed or were at risk for removing their properly positioned nasoenteric feeding tubes.

INTERVENTIONS

A length of one-eighth inch (3.2 mm) umbilical tape is looped around the nasal septum and vomer by serially attaching the ends of the umbilical tape to a suction catheter, passing the catheter through the nostrils, into the oropharynx, and retrieving the ends from the oropharynx. The properly positioned umbilical tape loops into one nostril around the vomer, and out the other nostril. The feeding tube is then anchored to the umbilical tape with a central venous catheter fastener clamp.

MEASUREMENTS AND RESULTS

Communicative patients denied discomfort, and there were no episodes of bleeding, infection, sinusitis, or nasal septal trauma caused by the umbilical tape bridle. Five patients had the bridle in place >30 days. There were only two cases in which the bridle failed to prevent removal of a feeding tube. One of these cases occurred because the fastener clamp anchor failed, but this patient had had the same bridle and feeding tube for 170 consecutive days.

CONCLUSIONS

An umbilical tape bridle with a central venous catheter fastener clamp anchor is a safe and effective method to prevent the accidental removal of nasoenteric feeding tubes in critically ill patients. We recommend its use in confused or uncooperative patients, or when the risk of unintentional feeding tube removal is high.