YaNuCa

YaNuCa is a web-tool to support the calculation of artificial nutrition for intensive care patients.

YaNuCa was originally released by nursix.org.

Current online version (for use directly from the WWW):

YaNuCa is free software. You are welcome to redistribute and/or modify it under the terms of the GNU Affero General Public License.

More information about YaNuCa can be found on YaNuCa Wiki.

The YaNuCa "Nutrition Model"

YaNuCa does not provide a formal model for artificial nutrition of ICU patients, but is simply a calculation tool. However, YaNuCa supports a certain method of building up enteral nutrition, which shall be described here in short.

General

YaNuCa calculates a nutrition plan on 5 levels - one level is for total parenteral nutrition (TPN) and four levels (1-4) for building up an enteral (tube-)nutrition.

To build up the enteral nutrition you usually start with level 1 and then step up one level per day.

For each level YaNuCa shows supply rates for enteral and parenteral nutrition solutions. The particular product for tube feeding can be chosen from the built-in database, while the parenteral nutrition is always assembled of 10% amino acid, 40% glucose and 20% lipid emulsion (however, no particular products named or recommended here).

Enteral Nutrition

Enteral nutrition is assumed to be supplied over a gastric tube in intervals of 4 hours on the given rate, each followed by a pause intended for tolerance checks and enteral medication.

Depending on how many of these 4-hour-cycles per 24 hours are neccessary to supply the calculated daily amount of enteral nutrients, the pause intervals may last for 1 or 2 hours (4 cycles/d=2h pause, 5 cycles/d=1h pause). The neccessary number of cycles per day is shown on the supply rates table.

Maximum Rate of Enteral Nutrition

YaNuCa allows a maximum enteral supply rate of only 150 ml/h, which is recommendable for the most products on the market. However, you may choose a lower maximum rate as necessary.

Passage Problems in Enteral Nutrition

If the patient shows passage problems in the enteral nutrition, you may consider to suspend one 4-hour-cycle, while clearing the cause. If the problem cannot be solved or persists despite appropriate counter measures, it is recommendable to suspend the whole enteral nutrition for the rest of the day - thus stepping down to TPN. In some cases, a lower maximum supply rate might help.

NOTE: in worst case (unluckily often) persistent severe passage problems indicate an enteral ischaemia, which may prohibit further enteral nutrition (increased risk for septic complications).

Water Balance

To support water balance calculation, the hourly water partition of the enteral nutrition is shown in the supply rates table (for parenteral solutions usually the full rate is used for the water balance). If you rather calculate the full volume of enteral nutrition for water balance, just ignore this line.

Parenteral Nutrition

For parenteral nutrition it is assumed that you supply the solutions continously 24 hours per day. The parenteral supply rates are calculated to complement the enteral nutrition to the full nutrition requirements of the patient. It is at your option whether to apply these parenteral complements or not, however, it is recommended to add them in patients with high risk for critical malnutrition.

At level 4 of enteral nutrition, YaNuCa tries to fulfill the calculated requirements solely from enteral nutrition. However, this may fail due to either the maximum supply rate for enteral nutrition (which is 150 ml/h or less if you set it) or due to unsuitable composition of macronutrients in the chosen formula (e.g., most products lack a sufficient protein quota). In these cases you will get parenteral complements calculated even at level 4. In anabolic phase, or if artificial nutrition applied longer than 5 days, is recommendable to supply these complements in any case, especially Amino Acids.

How to use YaNuCa

Overview

The YaNuCa front end is structured into four sections which shall be handled from top to bottom.

The upper (grey) section is used to declare the patient data.

In the middle (red) section you can choose the enteral formula, set a maximum enteral supply rate and declare possible oral intake of the patient.

The middle (yellow) section shows the calculated requirements and a desirable composition of macro nutrients. Within this section (on the right) you may choose ranges and set goals for this calculation manually. If you leave them on automatic, YaNuCa calculates them from built-in defaults.

The bottom (grey and blue) section shows the calculated supply rates for each level.

The whole document can simply be printed on one A4 sheet. Just press the "Print"-button of your browser.

Patient Data

These input fields explain themselves very well.

If the initial weight of the patient is unknown or cannot be measured properly, you can leave this field on "unkown". YaNuCa will then calculate a standard weight based on the other data you provided (the actually used weight is shown in the yellow section). If you choose a particular weight, the "Shape"-field will be ignored instead.

The assignment of an illness stress factor might be difficult. Moreover, stress factors are dynamic - they might vary for the same patient from day to day, therefore you should re-calculate the nutrition plan daily. The illness stress factor and the thermal stress factor below scale the requirements from 70 up to 200% of the estimated basal metabolic rate.

Enteral Formula and Oral Intake

In the middle (red) section you can choose a particular enteral formula.

The nutrient composition of the selected formula will guide YaNuCa in the calculation of the desired nutrient composition even for parenteral nutrition, i.e. if you choose a low-glucose formula, the calculated parenteral glucose supply rates will be lower as well.

Which product you should choose depends on the availability of this product as well as on the individual compatibility and needs of the patient. Therefore, the pre-selected product does not represent any recommendation at all.

If the patient can eat normally (an amount worth mentioning) then YaNuCa can include this into the calculation. To use this function, you just have to estimate the amount of orally assimilated food (in terms of energy) and make the appropriate selection in the "Oral Nutrition"-field.

That way you may also calculate a supportive (additional) parenteral nutrition, if the patient can eat normally but does not meet his requirements with it.

The Requirements Table

The requirements table shows the calculated requirements for the patient, and a desirable composition of macro nutrients that would fulfill these. The amounts of the particular macro nutrients and total energy supply are detailed as absolute (total daily amount) and relative (daily amount related to the patient weight) values.

The "Options" fields on the right enable you to manually influence the nutrient composition calculation. Your influence is limited to built-in supply limits as well as overall possibilities, hence you may set goals rather than precepts. So, sometimes your choices here might have no significant effect - mostly in cases where you operate at the outer edge of possibilities, anyway.