Neonatal TPN

Earlier in the week, I presented a patient case on a neonate who had undergone cardiac surgery to repair his transposition of the great arteries.  In his postoperative management, the patient developed a chylothorax, at which point the patient was placed on NPO until the fluid drainage from her chest tubes resolve.  To provide adequate nutrients to this growing baby during this time, TPN was administered.  

Since I was following this patient, I attached an addendum to my case presentation that included a SOAP of the TPN regimen given.  As my references, I looked at both NTUH's guidelines as well as Neonatal and Pediatric Parenteral Nutrition Support Guidelines from the University of Illinois at Chicago Medical Center.  

Neonatal TPN
S/O	1.      Patient is NPO due to a chlyothorax.
A	1.      Patient is NPO, and therefore, requires TPN to supply essential nutrients crucial to promote normal growth and development. 2.      Current TPN regimen: Concentration Rate Dextrose 17% 48.96 gm Aminosteril Infant 2.20% 2.64 gm/kg/day Na 30 mEq/L 3.60 mEq/kg/day K 30 mEq/L 3.60 mEq/kg/day Cl 30 mEq/L 3.60 mEq/kg/day Ca 25 mEq/L 3 mEq/kg/day P 10 mmol/L 1.2 mEq/kg/day Mg 5 mEq/L 0.6 mEq/kg/day Infuvita 5 mL Zn 188 ug Trace Element 50 uL Rate=340 mL @ 0.2 mL/min 3.      Calculations 　 Calculation Assessment Dextrose 48.96 gm/day x 1/2.4 kg x 1 day/24h x 1h/60 min x 1000 mg/g = 14.2 mg/kg/min Goal:  11-14 mg/kg/min; patient's dextrose rate is approximately the within the normal range Amino Acid 2.2%=2.2 gm/100 mL/day x 288 ml x 1/2.4 kg=2.64 gm/kg/day Goal:  ~3 gm/kg/day for preterm infant; patient's rate is appropriate Lipids 5 mL of 20% emulsion-->20gm/100mL x 5mL/2.4 kg=0.42 mg/kg/day Goal: start at 1gm/kg/day, max: 3gm/kg/day; slightly below goal Total Calories dextrose:  48.96 gm x 3.4 kcal/gm = 166.5 kcal; AA:  6.336 gm x 4 kcal/gm = 25.3444 kcal; lipid:  1 gm x 9kcal/gm = 9 kcal; Total=83.69 kcal/kg/day Goal:  40-50% of total caloric intake; dextrose consists of 83%; dextrose is above normal range Total Fluid 12 mL/h x 24 H = 288 mL; 288 mL/2.4 kg = 120 mL/kg/day Max:  140-150 mL/kg/day; total fluid is appropriate
P	Goal	·         Provide adequate nutrition while the patient is NPO ·         Fluid ·         Sodium ·         Protein ·         Carbohydrates ·         Fat ·         Electrolytes ·         Caloric intake ·         Increase lipids to at least 1gm/kg/day ·         Increase amino acids to ~ 3 gm/kg/day ·         Increase concentration of dextrose, may go up to 20-25% ·         Decrease percentage of dextrose to goal of 40-50%
	Monitoring	·      Ca, Cl, Mg, P, K, Na ·      Fluid overload ie edema, renal function ·      Total caloric intake ·      Dextrose ·      Amino Acids ·      Lipid

Similar to medication dosing for the pediatric population, the estimated energy needs, dextrose, protein, lipid, electrolyte and maintenance fluid requirements are based on patient weight.  The normal and goal ranges for each of the components are listed in my assessment above.  

In our schooling, we did not extensively go over TPN, let alone neonatal TPN.  We spent one lecture going over a case with Dr. Ferrone, and that was the end of it.  At NTU, the students are well trained in TPN and seem to have a relatively solid grasp on management of TPN components.  This may be because TPN is considered a very specialized sector of pharmacy in the US.  At NTUH, the TPN orders are done by different individuals, depending on which department of the hospital they are in.  On the PSICU service, the nurses did the TPN orders.  Once the orders are processed on their computer system, the TPN pharmacy verifies the order.  In certain departments, the TPN pharmacy does the order as well as the verification.  At UCDMC, the TPN pharmacy is a consult service, and thus, only the services that call for a consultation have the orders done by the TPN pharmacist.