1.          Calculation of maintenance fluids based on wt in kg.

        a) Over 24 hours:

                    i)  100 ml/kg for first 10 kg

ii) 50 ml/kg for next 10 kg

                    iii) 20 ml/kg for every kg above 20 kg.

                    iv) Divide by 24 for ml/hr or use 4 ml/kg for first 10 kg, 2 ml/kg for next 10 kg, and then 1 ml/kg for every kg above 20 kg.

            * If mechanically ventilated, the patient has minimal respiratory insensible losses due to the heated/humidified circuit. Thus, maintenance fluid requirements are generally ~80% of that calculated above.

2.          Fluids should be adjusted to take into account extra losses, fever, dehydration,additional volume from drips and other medications, fluid restriction, etc. Also paralyzed, 

            sedated, intubated patients have decreased insensible losses and thus decreased maintenance fluid requirements.

3.          Basic Nutrition Goals: for the critically ill intensive care patients:

a)  Energy Needs (Maintenance + Growth) 

                                                  Term Infant                                90‐120 kcal/kg/day

1‐3 yrs                                       75‐90  kcal/kg/day

4‐6 yrs                                       65‐75  kcal/kg/day

7‐10 yrs                                     55‐75  kcal/kg/day

11‐18 yrs                                   40‐45  kcal/kg/day

>18 yrs                                      20‐35  kcal/kg/day

b)          Protein Needs (Maintenance + Growth)

                                                            <1 yr                                         2‐4 gm/kg/day

1‐10 yrs                                     1‐1.2 gm/kg/day

Adolescent                               0.8‐0.9 gm/kg/day

> 1 yr Critically ill               1.5 times normal


Timing: Fivez et al, NEJM 2016, found in a RCT of 1440 PICU patients, improved clinical outcomes (shorter ICU stay (6.5 vs 9.2 days), less new infections (10.7 vs 18.5%), shorter hospital stay, less renal replacement therapy, and shorter duration of mechanical ventilation in patients started "late" (day 8 of ICU stay) vs early (within 24 hours of PICU admission). Basically, in general, starting TPN later is preferable based on the available evidence.

Reserved to patients in which enteral nutrition is contraindicated.

    1. Total needs and blood chemistry levels largely determine tolerance to parenteral 

    nutrition solutions. (Refer to TPN sheets for monitoring)

    a) Renal panel, Magnesium and Triglyceride should be checked daily until the patient is on 

        stable TPN.

    b) Blood sugars should be followed closely when on high GIR’s especially when weaning off 

        TPN in infants.

    2. Carbohydrates: GIR (glucose infusion rate) is the milligrams of dextrose delivered per 

        kilogram weight per minute:

            i) GIR = dextrose (gm/ml) x 1000 (mg/gm) x infusion rate (ml/hour)

               60 min/hour x wt (kg)

            ii)          Initial GIR needs

                                        Neonates                   6‐8 mg/kg/min   

                                        Infants                     5‐7 Mg/kg/min

Children                     3‐4 mg/kg/min

Adults                       1‐2 mg/kg/min

            iii)         Maximum GIR

                                        Infant/Pediatric Range  12‐14 mg/kg/min 

                                        Adult range         7 mg/kg/min

        a)          Increase by 20‐50%/day until at goal of total kcal

        b)          Should be up to 60‐70% of total calories

        c)          Excessive dextrose associated with fatty liver and increased VCO2

        d)          Calculate calories:

                (1)         grams of dextrose = total volume of TPN * Dextrose %

                (2)         Kcals from dextrose = grams of dextrose * 3.4 kcal/gm

    3. Amino Acids: Start at 1 gram protein/kg/day and advance by 0.5‐1 gm /kg/day until you 

        reach the goal unless contraindicated by alterations in protein metabolism, (ie. renal or liver 

        disease, inborn error of metabolism,...etc.).

              a)      Calculate calories

                    i)           gm/day AA = gm /kg/day * kg

                    ii)          kcal AA/day = gm/day AA * 4.3 kcal/gm

4.          Lipids: use the 20% solution at 0.5‐1gm/kg/day ...may increase to maximum of 3gm/kg/day

              a)    Calculate Calories: (25‐30% of total calories) There are 20 gms of lipid per 100 ml of 

                       20% lipid with 2 kcals/ml.

i)           ml of fat/day = total grams of fat/day * 5 ml/gm

ii)          kcal fat/day = ml/day x 2 kcal/ml

                b)    Lipids can be run over 12‐18 hours (in this institution). In neonates not to exceed 

                     0.15 gm/ml/hr.

                c)   Rapid infusion of lipids may be associated with a decreased lipid clearance &/or 

                       respiratory &/or platelet aggregation complications.

        Peripheral Parenteral Nutrition (PPN): may be use to support blood glucose levels &/or supply short 

        term nutrition support and may be use in transition to TPN (while waiting for central access).

        1.  Dextrose is usually not greater than 10% (final concentration) but can be maximized at 

             12.5 %.

        2.  The total osmotic limits of peripheral parenteral nutrition is near 800‐900 mOsm:

                a)          250 mOsm per 5% dextrose

                b)          100 mOsm per 1% amino acids

                c)          Pharmacy will determine if the components of the PPN affect the osmolality

Enteral Nutrition: 


    First choice whenever possible as it is associated with better patient tolerance 

    and outcomes. Significantly reduced risks. (Srinivasan et al, PCCM 2020)

1.          Feeding tubes may be placed in the stomach when the risk of aspiration or reflux is 

             relatively low

        a)          Transpyloric feeding tubes can be if there is altered G.I. function with delayed 

                     gastric emptying, (duodenal trophic feeding can be initiated even in the absence of bowel sounds).

        b)          Continuous delivery tube feedings are usually tolerated better that bolus feeding in 

                     the intensive care patients as this allows for slower delivery and minimal gastric distention.

        c)          When initiating tube feeds in the PICU please use the Gastric feeding protocol unless 

                     special circumstances (i.e. only giving trophic feeds, patients with known feeding issues)

2.          Formula Selection:

        a)          Most standard formulas are isotonic and appropriate for the majority of patients. 

                     Specialized formulas are indicated for problems of intolerance or special patient needs.

        b)          Hyperosmotic solutions can be used to reduce volume loads, yet some patients may 

                     occasionally develop diarrhea or delayed gastric emptying with these formulas, so individualized 

                     feeding rates may be necessary in these circumstances

3.          Infant formulas: are usually 20 kcal/oz (0.67 kcal/cc) in isotonic, starting solutions.

        a)           Breast milk is by far the best tolerated formula and should be utilized when ever 

                      possible. Powdered formula or fortifiers may be combined with pumped breast milk to increase the 

                 nutrient delivery in smaller volumes.

     b)          Cow milk based formulas such as: Enfamil & Similac are similar in composition to breast 

                 milk and are usually well tolerated.

     c)          Soy based formulas such as: Isomil & Prosobee are used for lactose intolerance or milk 

                     protein allergies (both are rare in infants).

        d)         Hypoallergenic formulas such as: Pregestimil, Nutramagen & Alimentum contain protein 

                     hydrolysates. Formulas such as Neocate and EleCare contain free amino acids and are indicated for 

                 infants sensitive to intact proteins, malabsorption and/or allergies.

        e)          Fat malabsorption due to damage to the lymphatic system or thoracic duct may require 

                     use of medium chain triglyceride containing formulas, such as: Portagen.

4.          Pediatric Formulas for 1‐10 years of age: are usually 1 kcal/ml (30 kcal/oz) in 

         isotonic, starting solutions

        a)          Pediasure & Nutren Jr. with fiber are lactose free and nutritionally complete in 1000 

                 ml for kids 1‐10 years of age.

       b)          Specialized Pediatric Formulas: Peptamen Jr., EleCare may be indicated for 

                     malabsorption, short bowel syndrome, and allergies.

5.           Adult Formulas (>10 yrs): are usually 1 kcal/ml & isotonic in the starting solutions.

        a)          Standard: Osmolite, Jevity contain fiber

        b)          Specialized formulas: i.e. high protein, low protein, high calorie may be used in 

                 special circumstances.

Source: Akron Children's PICU Resident Curriculum:, accessed 3/8/2016.

Benefits of EN

So we now know why it's important to start EN as soon as possible. But...

Gastric vs. Postpyloric Feeds

Theoretical benefit of reduced risk of aspiration with postpyloric feeds

Vasoactives and Enteral Nutrition

Complications with EN While on Vasopressor/Inotropic Agents

Overall, literature evaluating complications with EN + hemodynamic instability lacking and basically non-existent in the pediatric population. What are our current recommendations from the experts?


2009 Adult Guideline for Nutrition in the ICU

2009 Pediatric Guideline for Nutrition in the PICU

They're not very clear on whether EN should be started while on vasopressor/inotropic agents. What are the evidence behind starting vs. withholding EN in hemodynamically unstable pts?


2000 - EN in Adult Post-Cardiac Surgery Pts

2001 - Splanchnic Response to EN in Adult Post-Cardiac Surgery Pts on Pressors

2004 - Enteral Nutrition and CV Meds in the PICU (JPEN), attached

2010 - Early EN in Adult Pts with Pressors and Mechanical Ventilation (AJCC), attached

Bottom Line

Respiratory Quotient

Resting Energy Expenditure (REE)

Reference for  general review (Sion-Sarid et al, Nutrition 2013)

One model of REE on ECMO (have to essentially treat the membrane oxygenator/sweep as another lung): (DeWaele et al, Acta Anesthesiologica Scand 2015)


1) Kamat P, Favaloro-Sabatier J, Rogers K, Stockwell JA. Use of methylene blue spectrophotometry to detect subclinical aspiration in enterally fed intubatedpediatric patients. Pediatr Crit Care Med. 2008 May;9(3):299-303.

2) Meert KL, Daphtary KM, Metheny NA: Gastric vs small bowel feeding in critically ill children receiving mechanical ventilation: A randomized control trial.Chest 2004; 126:872–878

3) Fivez T, Kerklaan D, Mesotten D, Verbruggen S, Wouters PJ, Vanhorebeek I,Debaveye Y, Vlasselaers D, Desmet L, Casaer MP, Garcia Guerra G, Hanot J, JoffeA, Tibboel D, Joosten K, Van den Berghe G. Early versus Late Parenteral Nutritionin Critically Ill Children. N Engl J Med. 2016 Mar 15.

4)  Srinivasan V, Hasbani NR, Mehta NM, Irving SY, Kandil SB, Allen HC, Typpo KV, Cvijanovich NZ, Faustino EVS, Wypij D, Agus MSD, Nadkarni VM; Heart and Lung Failure-Pediatric Insulin Titration (HALF-PINT) Study Investigators. Early Enteral Nutrition Is Associated With Improved Clinical Outcomes in Critically Ill Children: A Secondary Analysis of Nutrition Support in the Heart and Lung Failure-Pediatric Insulin Titration Trial. Pediatr Crit Care Med. 2020 Mar;21(3):213-221.