EVALUATION OF NUTRITIONAL ADEQUACY OF A VOLUME BASED ENTERAL FEEDING
PROTOCOL IN A SINGLE CENTER TRAUMA/SURGICAL ICU
Ashley McCusker MD, Martha Betts MS, B M. Msall MS, Heather A. Prentice PhD, Anna N. Bradford PhD, Jeffrey
Wright MS, Elena Lita, and Erik Teicher MD.
Inova Fairfax Medical Campus, Falls Church, VA 22042
Background. The traditional protocol for intensive care unit (ICU) enteral feeding has been based on hourly goals.
Numerous studies have demonstrated that, when receiving feeding based on an hourly protocol, ICU patients receive
between 50-70 percent of recommended nutritional goals (1, 2). This can be detrimental while they are in a
hypercatabolic state. Volume based feeding has been shown to be a feasible alternative to hourly based feeding in
ICU and improve the delivery of the prescribed nutritional goal (3). We tested the hypothesis that patients will
receive on average at least 80 percent of their prescribed nutritional goals after the implementation of a volume
based tube feeding protocol, as compared to a historical hourly feeding protocol (4,5).
Methods. A daily volume based feeding goal was calculated based on the patient’s ideal body weight and daily
caloric needs. All patients received a standard bowel regimen and protein supplements. Gastric volume residuals
were liberalized to 500cc, with tube feeds held for one hour after a high residual, and promotility agents were
initiated with the first feed intolerance. Interruptions in tube feeds were minimized and reasons were documented.
Volume delivered was recorded for each morning and night shift to determine the daily volume received. The
average percentage of daily volume received over goal volume was calculated for patients and compared to the previous
hourly feeding protocol, as well as to published rates of delivery of enteral nutrition in the ICU population (1, 2).
Results. In a five month period, 85 patients received enteral feeding using a volume based protocol. Patients
received on average 82.8 percent of the prescribed nutritional goal using the volume-based protocol. In comparison,
only 66 percent of the prescribed nutritional goal was met using hourly feedings.
Conclusions. Preliminary data shows that the volume based enteral feeding protocol is feasible for a large level I
trauma/surgical ICU. The implementation of the volume based protocol improved the delivery of the prescribed
amount of enteral feeds while also calling attention to avoidable interruptions to enteral feeding.
Table. Patient Characteristics
Variable
Age, in years
Mean ± SD
Gender
Female
Male
Weight, in kg
Mean ± SD
Height, in cm
Mean ± SD
BMI, in kg/m2
Mean ± SD
<25
25 to <30
≥30
Goal Energy Prescribed, in kcals
Mean ± SD
Goal Volume Prescribed
Mean ± SD
Days from Admission to TF Initiation
Median (Min-Max)
Days from Admission to Discharge
Median (Min-Max)
Days on tube feeds
Median (Min-Max)
Times AM or PM tube feed reporting missed
Median (Min-Max)
Times patient received more than 100% volume prescribed
Median (Min-Max)
After (N=85)
58.4 ± 22.7
23 (27.1%)
62 (72.9%)
81.5 ± 23.2
172.5 ± 10.0
27.3 ± 6.8
39 (45.9%)
27 (31.8%)
19 (22.3%)
1796.5 ± 296.1
1197.7 ± 202.1
3 (0-57)
22 (4-72)
8 (1-50)
1 (0-8)
1 (0-12)
Table. Nutritional Adequacy
Variable
1. Excluding data where AM/PM missing
Mean ± SD
Median (IQR)
Hourly-Based
(N=37)
Volume-Based
(N=831)
p-value
66.3 ± 24.3
74.3 (62.7-82.8)
82.8 ± 0.19
83.6 (73.7-93.7)
0.0001
0.0004
Table. Sensitivity Numbers
Variable
2. Complete information recorded
Mean ± SD
3. Doubling data where AM/PM missing
Mean ± SD
Volume-Based
(N=85)
76.6 ± 19.1
85.1 ± 21.1
References:
1. Cahill et al, Nutritional Therapy in the critical care setting: What is “best achievable”
practice? An international multicenter observational study. Crit Care Med 2010, 38: 395-401.
2. McClave et al, Enteral Tube feeding in the intensive care unit: factors impeding adequate
delivery. Crit Care Med 1999, 27(7) 1252-1256.
3. Heyland et al, Enhanced protein-energy provision via the enteral route in critically ill patients:
a single center feasibility trial of the PEP uP protocol. Critical Care 2010, 14: R78
4. Albreda et al. The relationship between nutritional intake and clinical outcomes in critically
ill patients: results of an international multicenter observational study. Intensive Care Med 2009,
35: 1728-1737.
5. Heyland DK, et al. Optimal amount of calories for critically ill patients: depends on how you
slice the cake! Crit Care Med. 2011;39(12):2619-26.