Enteral Nutrition vs. Total Parenteral Nutrition

Author/Year/ Country/Study design/PEDro Score/N





Mousavi et al. (2014)

Population: TBI; Gender: Male=26, Female=0. Intervention Group (n=13): Mean age=31yr; Mean GCS Score=7.3. Conventional Group (n=13): Mean age=36.6yr; Mean GCS Score=8.4.
Treatment: Patients on parenteral nutrition were randomly allocated to receive continuous infusion of 50 IU insulin (IIT; intervention) or conventional glucose treatment (CGC; control). ITT group had blood glucose (BG) levels maintained at 80 mg/dl – 120 mg/dl. Patients were followed up on day 7 and 14.
Outcome Measures:
Frequency of hypoglycemic episodes, BG concentration. Secondary outcome measures: mid-upper arm circumference (MAC), C-reactive protein (CRP), lipid profile, blood electrolytes, and liver function tests.

  1. Mean BG concentration was significantly lower in the IIT group compared to the CGC group (118±28mg/dl vs. 210±31mg/dl; p<0.01). The CGC group had more hyperglycemic episodes.
  2. There were no significant between group differences in any of the  secondary outcome measures on day 7 follow-up (p>0.05).
  3.  On day 14, patients receiving IIT had significantly lower levels of CRP (p=0.0001), triglycerides (p=0.02), magnesium (p=0.03), and phosphorus (p=0.01). Chloride levels were significantly elevated in IIT patients compared to CGC patients (p=0.02). These changes were largely in accordance with the hormonal effects of insulin.


Dhandapani et al. (2012)


Population: TBI; Time Post-Injury ≤24hr; Total enteral feeding (≤3d) Group: Mean Age=31.7yr. Total enteral feeding (4-7d) Group: Mean Age=34.4yr. Total enteral feeding (>7d) Group: Mean Age=37.2yr.
Treatment:  Participants were administered enteral feeding through nasogastric tube or orally. Feeding began as early as possible. The volume of feed was increased gradually in keeping with an individual’s gastric tolerance.
Outcome Measure: Glasgow Outcome Scale (GOS), mid-arm circumference (MAC), mid-arm muscle circumference (MAMC), and serum total protein.

  1. Those receiving total enteral feeding >7 d post-injury lost significantly more MAC and MAMC compared to those in the earlier fed groups (p≤0.001).
  2. Analysis of total serum protein revealed that more malnutrition was seen in those who received total enteral feeding >7 days post-injury (p≤0.005).
  3. At the 3 and 6 mo follow-up, those receiving total enteral feeding within the first 7 d were more likely to have favorable outcomes on the GOS.

Meirelles and de-Aguilar-Nascimento (2011)


Population: TBI; Enteral Nutrition (EN) Group: Mean Age=31; Gender: Male=11, Female=1; Mean GCS Score=9. Parenteral Nutrition (TPN) Group: Mean Age=31; Gender: Male=9, Female=1; Mean GCS Score=9.
Treatment: Patients were randomized to receive either EN or TPN. Both groups received a 25-30kcal/kg/day and 1.5g/kg/day of protein. EN was administered via 8 or 10F oro- or naso-enteral feeding tube in gastric position with pump infusion. TPN was administered via central venous access. Patients assessed daily for 5d.
Outcome Measure: Mortality, morbidity, Length of stay (LOS) in ICU, days of mechanical ventilation, amount of calories and protein received/d, blood samples of glucose, albumin, urea, creatinine, C-reactive protein (CRP), urinary urea (N).

  1. No significant differences were found in morbidity and mean ICU LOS between the EN and TPN group.
  2. Although the amount of calories increased significantly (p<0.01) each day of the study, there was a progressive caloric deficit (p=0.001) in the two groups without any significant difference between them.
  3. Those in the TPN group received significantly more (p<0.006) nitrogen than the EN group.
  4. Despite the increased loss of nitrogen, all patients showed significant improvement (p=0.001) in the nitrogen balance as a result of nutritional therapy.
  5. Even though each nutritional therapy offered increasing quantities of nitrogen and calories, the TPN therapy delivered nitrogen more efficiently compared to the EN therapy.

Ott et al. (1999)
Case Control


Population: Head Injury; Mean Age=31yr; Gender: Male=44, Female=13.
Treatment: Patients received enteral nutrition (EN; n=30) or total parenteral nutrition (TPN; n=27).
Outcome Measure: Cost of delivering care.

  1. Overall cost of EN was $170/patient/d.
  2. Overall cost of TPN was $308/patient/d.

Nataloni et al. (1999)


Population: Head injury; Mean Age=28yr; Gender: Male=31, Female=14. Group A (n=15): Mean GCS Score=6. Group B (n=15): Mean GCS Score=6. Group C (n=15): Mean GCS Score=5.
Treatment:  Patients were randomly administered one of the following feeding conditions: enteral (Group A), parenteral (Group B), or both enteral and parenteral (Group C). Those who participated were expected to stay in ICU for ≥3 d. Feeding began within 2 d of ICU admission and continued for the length of stay.
Outcome Measure: Serum pre-albumin, retinol-binding protein (RBP), nitrogen balance. Assessments were made at baseline and after (day 3, 7 and 11).

  1. Nitrogen balance, which was negative for all groups, improved over the course of treatment; however it only significantly improved in Group A by day 11 (p<0.0001).
  2. Plasma albumin levels remained unchanged in all groups.
  3. A closer look at the data revealed pre-albumin and RBP significantly increased in Group A compared to both Group B (p<0.001) and Group C (p<0.01). Significant differences in the level of pre-albumin began at day 3 (p<0.01) while the differences in the level of RBP began at day 7 (p<0.01).

Borzotta et al. (1994)


Population: Closed Head Injury; Gender: Male=40, Female=9; Early Parenteral Nutrition (TPN) Group (n=21): Mean Age=28.9yr; Mean GCS Score=5.4. Enteral Feeding (ENT) Group (n=28): Mean Age=26.2yr; Mean GCS Score=5.2.
Treatment: Patients in the TPN group were treated with early parenteral nutrition which at day 5 began conversion to gastric feeding with tapering of TPN. The ENT group had enteral feeding through jejunal tubes. Assessments made daily for 10 d and weekly for 5 wk thereafter.
Outcome Measure: Measured Energy Expenditure (MREE), nitrogen excretion, complications.

  1. No significant differences noted for nitrogen excretion or balance, energy expenditures, meeting nutritional goals, and frequency of infections.
  2. Patient complications such as hyperglycemia (p<0.05) and diarrhea (p<0.05) were more common among patients receiving TPN.
  3. Efficiency of feeding, measured by ratio of calories to MREE, showed an advantage for TPN at day 3, but none after.
  4. There were no differences in mortality at the end of follow-up.

Young et al. (1987)


Population: Severe Head Injury. Parenteral nutrition (TPN) Group: Mean Age=29.9yr. Enteral feeding (EN) Group: Mean Age=33.8yr.
Treatment:  Patients were randomly assigned to receive either TPN or EN. TPN was initiated within 48 hr post-injury. EN was initiated when tolerated by patients. Study went from admission to day 18. Assessments made every 6 hr in the ICU, or 1×/d in the hospital ward.
Outcome Measure: Intracranial pressure (ICP), nutrition.

  1. No significant differences were found between groups in peak daily ICP; ICP was >20mmHG in 75% of the TPN patients and 73% of the EN patients.
  2. Standard therapy was ineffective in controlling elevated ICP in 36% of the TPN and in 38% of the EN group.
  3. There were no significant between-group differences in serum osmolality.
  4. For the first 12 d, the TPN group received more calories and protein than the EN group (p=0.0001).
  5. There was a significant day × nutrition group interaction (p<0.0001); serum glucose levels were higher in the TPN group for the first 13 d post-injury than EN group who had increased mean serum glucose content after 13 d.

Hadley et al. (1986)


Population: TBI; Median Age=28yr; Gender: Male=40, Female=5; Mean GCS Score=5.8; Time Post Injury=6hr.
Treatment: Patients were randomly assigned to receive either total parenteral nutrition (TPN; n=24) or enteral nutrition (NG; n=21). Patients received high nitrogen and calorie feedings for a 14 d period of the study to try to obtain a positive nitrogen and calorie balance. Nitrogen loss was measured every other day.
Outcome Measure: Urinary nitrogen levels.

  1. Patients who received TPN achieved significantly higher mean daily nitrogen intakes (p<0.01) and losses (p<0.001) compared to those who received NG. 
  2. There was no significant between-group difference in nitrogen balance.

Hausmann et al. (1985)

Population: ABI; Mean Age=28.65yr; Gender: Male=20; GCS Range=5-7. 
Treatment:  Patients were randomly assigned to one of the following feeding regimes: total parenteral nutrition (TPN; n=10) or the combined enteral-parenteral nutrition (CN; n=10). All received maximal glucose intake of 500g/d and sorbitol of 100g/d. Parenteral nutrition  was administered continuously via a central venous line over 24 hr. Enteral feeding was administered through a nasogastric tube at 2 hr intervals. Daily fluid balance was corrected with electrolyte solutions or through the use of diuretics. Patients were assessed up to 8 d post-injury.
Outcome Measure: Nitrogen Balance, protein concentration.

  1. In the CN group, 4 (40%) patients died, whereas in the TPN group, 2 (20%) patients died. The difference in mortality was not significant.
  2. Regurgitated gastric fluid was lower in the TPN group compared to the CN group going into day 7 (p<0.05).
  3. Protein concentration of the reflux fluid in the CN group (1.1-4.2g/dl) was significantly elevated compared to the TPN group (0.53-0.84 g/dl) (p<0.05).
  4. Regardless of the feeding regime, nitrogen balance (NB) could not be reached.

Rapp et al. (1983)


Population: Head injury; Standard enteral nutrition (SEN) Group (n=18): Mean Age=34.9yr; Mean GCS Score= 7.2. Total Parenteral nutrition (TPN) Group (n=20): Mean Age=29.2yr; Mean GCS Score=7.7.
Treatment: Patients were randomly assigned to either the SEN or TPN group. TPN therapy was initiated within 48 hr of admission. EN was given via nasogastric tubes and initiated when tolerated.
Outcome Measure: Nutritional status (serum albumin, nitrogen balance, and daily calorie and nitrogen intake). 

  1. No baseline between group differences with the exception of mean peak temperature during the first 24 hr of hospitalization; TPN group had a higher mean temperature than SEN group (38.6ºC vs. 38.0ºC; p=0.02).
  2. Within the 18 d period, 8 of the 18 patients died in the SEN group compared to 0 deaths in the TPN group (p<0.0001).
  3. The TPN group had a significantly greater mean intake in nitrogen/d then the SEN group (10.2gm vs. 4.0gm; p=0.002); the overall nitrogen balance was also significantly different between groups (p=0.002).
  4. No significant between group difference was found in serum albumin levels over time.

PEDro = Physiotherapy Evidence Database rating scale score (Moseley, Herbert, Sherrington, & Maher, 2002).