Enteral Nutrition Support Therapy for Adults
Manual of Clinical Nutrition Management B- 46 Copyright © 2013 Compass Group, Inc.
Requirements or Section III: Burns.)
In critically ill adult patients the promotion of glucose levels between 140 and 180 mg/dL is currently
recommended by the Academy of Nutrition and Dietetics (Grade II) (3). Tight blood glucose control (80 to 110 mg
per dL) is not associated with reduced hospital length of stay (LOS), infectious complications, cost of medical
care, days on mechanical ventilation or mortality and increases risk of hypoglycemia as previously suggested
(Grade II) (3). However, glucose level > 180 mg/dL is associated with increased mortality in the critically ill adult
patients (Grade II) (3). In surgical (primarily cardiac) patients, tight control of blood glucose reduces the risk of
some types of infectious complications. However, this effect has not been consistently demonstrated in other
types of ICU patients (Grade II) (3). ASPEN guidelines recommend a target range of 100 to 150 mg/dL when
providing nutrition support therapy to critically ill patients (5). In addition, specific recommendations are
also provided for critically ill patients with diabetes. Dietitians should be involved in promoting the
attainment of blood glucose control when providing nutrition support therapies and should refer to emerging
evidence, practice guidelines, and facility-specific protocols for recommendations (3,5). Refer to Section C:
Medical Nutrition Therapy for Diabetes Mellitus for specific glycemic goals in managing hospitalized patients
with diabetes mellitus.
Suggested laboratory monitoring guidelines include:
daily measurements of sodium, potassium, chloride, CO 2 , blood urea nitrogen, creatinine, and glucose
levels until stable, then biweekly to weekly measurements
baseline measurements of prealbumin or albumin for patients, such as chronic kidney disease patients, to
determine the morbidity, mortality, or severity of disease or inflammatory status (not reliable in critically
ill patients)
baseline measurements of liver function tests
daily measurements of calcium, magnesium, and phosphorus until stable, then weekly measurements
baseline complete blood cell count, then measured as needed
a 24-hour urine analysis for urine urea nitrogen (or total urea nitrogen) once the goal rate of tube feeding
is attained, then weekly measurements until stable
Other patient monitoring guidelines:
Weigh the patient at least once per week.
Maintain daily records of intake, output, and bowel movements.
Monitor vital signs to determine whether a systemic inflammatory response is present ( 5 ). The systemic
inflammatory response syndrome is nonspecific and common in critical care patients. Its presence on the
second day after ICU admission prognosticates morbidity (organ failure) and mortality and therefore
might be one criterion in identifying the patient at higher risk for complications and who might benefit
from early initiation of enteral feeding (64). Signs of systemic inflammatory response syndrome include
the following (65):
body temperature of >38.0°C or <36.0°C
heart rate of >90 beats/minute
breathing rate of >20 breaths/minute (often obscured by mechanical ventilation)
leukocyte count of >12,000 mm^3 or <4,000 mm^3 , or a left shift (>10% bands)
Medications via enteral feeding tubes: Feeding tubes should be irrigated with at least 15 mL of warm
purified or sterile water (or saline) before and immediately after the administration of medications (52). Since
crushed medications can clog tubes, liquid medications should be used when possible. Many oral medicines
formulated for slow release may be surrounded by an enteric coating and should not be crushed and
administered through the feeding tube. Multiple types of medication should be administered separately (52).
Temporary cessation of enteral feeding may be indicated for 1 hour before and 1 hour after the
administration of phenytoin sodium (Dilantin), a commonly used anticonvulsant medication, because
components of the enteral formula, such as calcium, decrease the bioavailability of this drug (15,6 6 - 68 ).
Transitional feedings, enteral to oral or supplemental parenteral nutrition: Depending on the
swallowing function of the patient, oral intake should begin with liquids and advance to appropriate foods as
tolerated. When oral intake reaches 500 kcal or more, the dosage of tube feedings may be proportionately
tapered. Switching the patient from a continuous tube feeding to night tube feeding only or discontinuing
tube feeding 1 to 2 hours before meals will often stimulate the appetite and speed transition to adequate oral
intake. When oral intake consistently meets or exceeds 60% of the patient’s energy requirements and 100%