Dōsys
Parenteral Nutrition

Dōsys clinical workspace

Evaluation release

Parenteral nutrition calculator

Dōsys Adult Parenteral Nutrition Initiation and Formulation Review Protocol · Draft by Mario Cardenas, PharmD, MBA

Explore a regimen. See the arithmetic. Change an input and inspect the consequences.

Evaluation only · Synthetic adult cases · Not for patient care

This working prototype has software tests but has not completed independent clinical validation. It offers draft starting recommendations for eligible synthetic cases and calculates quantities from entered targets; it does not confirm clinical safety. Do not enter patient information.

01 · Case & administration

User-selected weight. No ideal or adjusted weight is chosen automatically.

Switching units converts the entered weight.

Exclude the separate lipid volume. Include all other additives in the final volume.

Constant rate only. Tapered/cyclic schedules with changing rates are not supported.

Clinical pathway & current labs

ASPEN-based reference guidance for synthetic adult cases. Record laboratory values without patient identifiers. Maintenance nutrients and urgent electrolyte replacement are separate decisions.

Electrolytes, glucose & triglycerides

Use the displayed units. Enter the reporting laboratory’s lower and upper reference limits; blank values never count as normal. Reference intervals are not treatment thresholds. Ionized calcium is required; total calcium cannot be substituted.

Sodium (mEq/L) · missing

Potassium (mEq/L) · missing

Magnesium (mg/dL) · missing

Phosphorus (mg/dL) · missing

Ionized calcium (mmol/L) · missing

Chloride (mEq/L) · missing

Bicarbonate / total CO₂ (mEq/L) · missing

Glucose (mg/dL) · missing

Triglycerides (mg/dL) · missing

Draft starting recommendation

Stable reference: 20–30 kcal/kg/day and 0.8–1.5 g protein/kg/day. ICU reference: 12–25 kcal/kg/day in the first 7–10 days and 1.2–2 g protein/kg/day. Ranges guide assessment; they are not mandates to deliver full targets immediately.

The Dōsys evaluation template selects the lower energy/protein endpoints, lipid 0.5 g/kg/day and remaining energy as dextrose after other calories. Its specific combination is a draft protocol choice, not an ASPEN-prescribed formula.

Maintenance reference: Na/K 1–2 mEq/kg/day each; Ca 10–15 mEq/day; Mg 8–20 mEq/day; phosphorus 20–40 mmol/day. The template selects lower endpoints, Infuvite Adult 10 mL and Tralement 1 mL. Individualize chloride/acetate, losses, other intake and micronutrients.

Why automatic starting doses are unavailable (17)
  • Enter an adult age (18–120 years); pediatric cases are outside scope.
  • Enter a valid clinician-selected calculation weight.
  • Complete acuity, renal and refeeding assessments.
  • Hours since lab collection: enter the age of the oldest result in hours.
  • Laboratory acknowledgment outstanding: confirm that values, units, reference intervals and collection time have been checked.
  • Sodium: enter a result and the reporting laboratory’s reference interval.
  • Potassium: enter a result and the reporting laboratory’s reference interval.
  • Magnesium: enter a result and the reporting laboratory’s reference interval.
  • Phosphorus: enter a result and the reporting laboratory’s reference interval.
  • Ionized calcium: enter a result and the reporting laboratory’s reference interval.
  • Chloride: enter a result and the reporting laboratory’s reference interval.
  • Bicarbonate / total CO₂: enter a result and the reporting laboratory’s reference interval.
  • Glucose: enter a result and the reporting laboratory’s reference interval.
  • Triglycerides: enter a result and the reporting laboratory’s reference interval.
  • Creatinine (mg/dL): enter a result. Renal status requires clinical assessment, not creatinine alone.
  • Urine output (mL): enter the measured volume, including 0 if none.
  • Urine collection period (hours): enter the observation period, from 6 to 24 hours. Shorter periods cannot be compared with the 6-hour KDIGO urine criterion.

For individualized plans, enter the energy target, amino-acid grams and lipid grams below. The target must include all energy sources. The button calculates the remaining dextrose; it does not choose clinical targets.

Clinical sources & limitations

ASPEN guidance does not supply a universal serum-level-to-PN-dose algorithm. This draft requires local clinical validation. No automated diagnosis of renal failure, refeeding syndrome or PN indication. Renal consistency checks only flag entries that contradict the selected pathway. KDIGO 2012 AKI recommendation 2.1.1 (urine volume <0.5 mL/kg/h for 6 hours). Creatinine is compared only with the reporting laboratory's entered reference interval, because KDIGO creatinine criteria need a baseline that a single value cannot supply.

Laboratory recency policy 2026-09-18.1: One daily monitoring interval (baseline, then daily until stable: NICE CG32; K/Mg/P before initiation: ASPEN refeeding consensus 2020). No guideline states a universal hour cutoff.

02 · Entered macronutrients
US ingredient catalog · Product strengths describe the stock solution, not the final bag. Entered grams determine nutrient totals and the selected stock strengths determine product volumes.

No product preselected.

No product preselected.

Enter 0 explicitly if no lipid is included.

May differ from the aqueous bag duration.

No product preselected.

03 · Energy accounting

Combined oral, enteral, propofol and other IV calories. Count each source once; enter 0 if none.

Includes PN and other sources. May be populated by the draft recommendation or entered by the specialist.

04 · Formulation products

Record the products used in the synthetic case. Calcium–phosphate model eligibility uses these selections; enter their total amounts in the next section. The daily quantity worksheet uses these exact products and the entered doses. Osmolarity still requires independent verification.

No product preselected.

No product preselected.

The calcium–phosphate section below evaluates supported formulations against a published empirical model. Exact product selection alone does not establish compatibility.

Other electrolytes, micronutrients & diluent

No product preselected.

No product preselected.

No product preselected.

No product preselected.

No product preselected.

No product preselected.

No product preselected.

No product preselected.

Catalog 2026-09-17.1 · Labels checked 2026-09-17. Selected US formulations, not a utilization ranking or inventory feed. Confirm the exact label and local availability. Premixed multi-chamber bags are outside this ingredient workspace.

Daily additive doses

Enter 0 explicitly for an omitted dose and select “not included” or its exact product. Calcium and phosphorus doses in the next section also drive this worksheet. Sodium/potassium targets include the phosphate salt contribution; the remainder after acetate is supplied as chloride.

Choose acetate using the acid–base assessment; amino-acid solutions also contribute acetate (and Travasol contributes chloride). Quantities are PN maintenance inputs, not bolus replacement orders. Account separately for non-PN electrolytes and fluid.

05 · Calcium–phosphate compatibility

Published-model prediction for Clinisol or Travasol with calcium gluconate and inorganic phosphate. Evaluation with synthetic cases only; independent clinical validation is pending.

Elemental calcium equivalents, not mg of calcium gluconate or serum calcium. 1 mmol calcium = 2 mEq.

Include inorganic phosphate from all sources in this PN bag. Do not enter a serum concentration.

Complete the regimen and evaluation acknowledgment to assess

Calculation, evidence & limits

Solution factor = calcium (mEq/L)^0.863 × phosphate (mmol/L)^1.19 ÷ final amino acids (%). The paper assigns an amino-acid factor of 100 to Clinisol and Travasol. This implementation supports no added cysteine.

The limit is 100 for aqueous PN with lipid on a separate line. For a combined bag or Y-site lipid, the limit is 100 − (lipid g × 100) ÷ (amino-acid g × 10). A solution factor strictly below the limit meets the model. Equality does not pass.

Separate lipid volume is not included in aqueous calcium/phosphate concentrations. The empirical model does not measure pH, particles or solubility in the actual bag, and does not verify exact manufacturer lots or Y-site compatibility with medications. Plenamine, Prosol, custom products, added cysteine, nonstandard storage and dextrose above 30% are not assessed. Neither central nor peripheral access changes this prediction.

Anderson et al., Hospital Pharmacy (2022), equations 1–4 and Table 1 · anderson-2022-adult-evaluation-v1

SMOFlipid manufacturer stability reference is separate supporting material; it is not used as a universal calcium–phosphate solubility curve.

06 · Central & peripheral access

Classify by catheter tip location. A midline is peripheral; a PICC requires appropriate central tip confirmation.

Select central or peripheral access.

Access selection does not change the calcium–phosphate prediction. Central administration does not resolve precipitation risk.

After the first calculation, results update as you edit. Calculator inputs stay in page memory and are cleared on reload; they are not sent to Dōsys or included in analytics events.

Regimen arithmetic

Awaiting inputs

Your calculation will appear here

Enter a synthetic regimen or load the example. No clinical doses are preselected.

Clinical review still required

The calcium–phosphate result is an empirical prediction for supported formulations, not confirmation of actual bag compatibility. Clinical pathways flag review needs but do not validate treatment. Lipid label checks cover only the configured dose, rate and duration statements. Other product limits, allergies, individualized micronutrients, stability, compounding technique and complete access suitability still require independent assessment. Osmolarity is not calculated. Results are not a safety clearance.

Methods & sources

Dextrose energy = g × 3.4 kcal/g. Amino-acid energy = g × 4 kcal/g (conventional accounting assumption).

Lipid volume = g ÷ (concentration % ÷ 100). Lipid energy = mL × labeled kcal/mL.

GIR = dextrose g × 1,000 ÷ (weight kg × bag hours × 60). This is a constant-rate value, not a peak value for a tapered infusion.

Lipid rate = g ÷ (weight kg × lipid hours). In a combined bag, lipid and bag hours are identical. Fluid rate = bag mL ÷ bag hours.

Concentration % w/v = grams × 100 ÷ final bag mL. Weight conversion: lb × 0.45359237 = kg. No intermediate rounding; displayed precision is not a compounding instruction.

Separate lipid volume is added to the aqueous bag volume once. Combined-bag volume already includes lipid. Other-source energy is user-entered and does not contribute to PN-specific GIR or protein results.

Source review: September 18, 2026. Arithmetic unchanged from 0.4.0; version 0.5.0-evaluation. Independent clinical review pending.