TPN BLOOD MONITORING GUIDELINES IN PICU 
                                                                                                                                                                                                                                   
                                                                  
                                                                  
                                                                  
                                                                  
                                                                  
                                                                 PURPOSE  
                                                                 The purpose of this document is to describe the laboratory samples to be drawn for children on total 
                                                                 parenteral nutrition (TPN) admitted to PICU. 
                                                                 POLICY STATEMENTS 
                                                                 TPN may be indicated in children who cannot meet their nutritional requirements by the oral/enteral route, 
                                                                 because either the gastrointestinal tract is non-functional or enteral access cannot be achieved and 
                                                                 maintained. 
                                                                  
                                                                 In PICU, TPN is generally run as a continuous 24-hour infusion of the amino 
                                                                 acid/dextrose/electrolyte solution.  This allows for: 
                                                                                                           Closer management of electrolytes, acid-base balance and fluid status 
                                                                                                           Provision of a consistent glucose infusion rate which may help with impaired glucose metabolism 
                                                                                                            often seen in stressed or critically ill patients 
                                                                                                           Less frequent handling of the equipment than with cyclic infusions, which may reduce the risk of 
                                                                                                            infection 
                                                                                                           Less frequent manipulation of the pump rate, thereby reducing the risk of infusion errors. 
                                                                 In PICU, lipids are generally run as a 20-hour infusion.  This allows lipids to be held for 4 hours before 
                                                                 drawing blood work for a fasting triglyceride level. 
                                                                  
                                                                 There are many potential complications of TPN including:  macronutrient-related (i.e. over- or under-
                                                                 feeding dextrose, amino acids, lipids); metabolic-related (i.e. excess or insufficient delivery of sodium, 
                                                                 potassium, magnesium, calcium, phosphate); GI/hepatobiliary-related (i.e. cholestasis, villus atrophy, 
                                                                 steatosis); and, infection-related (i.e. contamination of peripheral or central line).  Therefore, all patients 
                                                                 receiving TPN are to have blood monitored regularly to help assess tolerance to initiation, advancement 
                                                                 and discontinuation of TPN.  The frequency of monitoring depends on the child’s clinical condition and may 
                                                                 be program-specific (e.g. PICU, NICU, Oncology). 
                                                                 SITE APPLICABILITY 
                                                                 BCCH – Pediatric Critical Care Program (PICU) 
                                                                 PRACTICE LEVEL/COMPETENCIES 
                                                                 Only qualified prescribers may order TPN. 
                                                                 DEFINITIONS 
                                                                 Total Parenteral Nutrition (TPN) – an intravenous solution consisting of dextrose, amino acids, lipids, 
                                                                 sodium, potassium, magnesium, calcium, phosphate, acetate, chloride, vitamins and trace elements. 
                                                                 PROCEDURES  
                                                                  
                                                                 1.  TPN solutions are to be infused over 24-hours in PICU, unless otherwise ordered. 
                                                                 2.  Lipids are to be infused over 20-hours in PICU from 0600h to 0200h, unless otherwise ordered. 
                                                                 3.  TPN blood work is to be drawn at 0600h, after lipids have been held for 4-hours and before restarting 
                                                                                       the lipid infusion. 
                                                                 4.  Peripheral/central lines are to be accessed for blood work as per BCCH Nursing Policies and 
                                                                                       Procedures.  
                                                                 5.  In PICU, TPN blood samples are to be drawn on Thursdays at 0600h, unless otherwise ordered. 
                                                                 Policy #                                                                         PICU Manual                                                             Page 1 of 3 
                                                                                                                                                                                                                 Refer to online version – Print copy may not be current – Discard after use 
                                                                  
                                                                                                                                                                                                                                                                                                                                                                                                                         
                                                                                                                                                                                                                                                                        TPN BLOOD MONITORING GUIDELINES IN PICU 
                                                                                                                                                                                                      
                                                          
                                                          
                                                          
                                                          
                                                          
                                                         Below are the typical blood monitoring guidelines for PICU.  Additional labs may be ordered based on 
                                                         patient’s clinical condition or physician discretion. 
                                                          
                                                         For patients starting on TPN:  “BASELINE TPN BLOOD WORK” 
                                                         Do the following blood work daily for 3 days @ 0600h (starting the morning after TPN is initiated): 
                                                                                                                                                          Parameter                                                                                                                                                      Minimum Blood Volume 
                                                                                                                                                          1.  Sodium                                                                                                                                                     Lithium heparin microtainer:  0.7 mL 
                                                                                                                                                          2.  Potassium 
                                                                                                                                                          3.  Magnesium 
                                                                                                                                                          4.  Phosphate 
                                                                                                                                                          5.  Urea 
                                                                                                                                                          6.  Creatinine 
                                                                                                                                                          7.  Blood Glucose 
                                                                                                                                                          8.  Triglycerides 
                                                                                                                                                          9.  Bicarbonate 
                                                                                                                                                          10. Chloride  
                                                                                                                                                          1.  Ionized calcium                                                                                                                                            Heparinized blood gas syringe:  0.2 mL  
                                                                                                                                                          2.  pH                                                                                                                                                         (NOTE:  Only draw this sample if blood 
                                                                                                                                                                                                                                                                                                                         gases are not already being checked) 
                                                          
                                                         For all patients on TPN:  “STANDARD TPN BLOOD WORK” 
                                                         Do the following blood work on Thursdays @ 0600h, unless otherwise ordered: 
                                                                                      Parameter                                                                                                                                                                       Frequency                                                                                                            Minimum Blood Volume 
                                                                                      1.  Sodium                                                                                                                                                                      Every Thursday                                                                                                       Lithium heparin microtainer:  0.7 mL 
                                                                                      2.  Potassium 
                                                                                      3.  Magnesium 
                                                                                      4.  Phosphate 
                                                                                      5.  Urea 
                                                                                      6.  Creatinine 
                                                                                      7.  Blood Glucose 
                                                                                      8.  Triglycerides 
                                                                                      9.  Bicarbonate 
                                                                                      10. Chloride 
                                                                                      1.  Ionized calcium                                                                                                                                                             Every Thursday                                                                                                       Heparinized blood gas syringe:  0.2 mL  
                                                                                      2.  pH                                                                                                                                                                                                                                                                                               (NOTE:  Only draw this sample if blood 
                                                                                                                                                                                                                                                                                                                                                                                           gases are not already being checked) 
                                                                                      1.  CBC with differential                                                                                                                                                       Every 2nd Thursday                                                                                                   Lavender EDTA microtainer:  0.3 mL 
                                                                                      1.  Albumin                                                                                                                                                                     Every 2nd Thursday                                                                                                   Lithium heparin microtainer:  0.5 mL 
                                                                                      2.  ALT 
                                                                                      3.  AST 
                                                                                      4.  Alkaline phosphatase 
                                                                                      5.  Conjugated bilirubin 
                                                                                      6.  Unconjugated bilirubin 
                                                                                                                                                                                                                                                                                                         th
                                                                                      1.  Zinc                                                                                                                                                                        Every 4  Thursday                                                                                                    Dark blue tube no additives:  1 mL 
                                                                                      2.  Selenium 
                                                                                      3.  Copper 
                                                                                      4.  Manganese (NOT magnesium) 
                                                         Policy #                                                                         PICU Manual                                                             Page 2 of 3 
                                                                                                                                                                                      Refer to online version – Print copy may not be current – Discard after use 
                                                          
                                                                                                                                                                                                                                                                                                                                                                                                                         
                                                                                                                                                                                                                                                                        TPN BLOOD MONITORING GUIDELINES IN PICU 
                                                                                                                                                                                                      
                                                          
                                                          
                                                          
                                                          
                                                          
                                                          
                                                         DOCUMENTATION 
                                                         A copy of TPN orders will remain in the patient’s chart. 
                                                         REFERENCES 
                                                         Corkins MR, Griggs KC, Groh-Wargo S, Han-Markey TL, Helmes RA, Muir LV, Szeszycki EE, Task Force 
                                                         on Standards for Nutrition Support:  Pediatric Hospitalized Patients, and American Society for Parenteral 
                                                         and Enteral Nutrition Board of Directors.  Standards for Nutrition Support:  Pediatric Hospitalized Patients.  
                                                         JPEN J Parenter Enteral Nutr.  2013;28:263-276. 
                                                          
                                                         Crook MA.  Lipid clearance and total parenteral nutrition:  the importance of monitoring plasma lipids.  
                                                         Nutrition.  2000;16:774-775. 
                                                          
                                                         Mirtallo JM.  Overview of Parenteral Nutrition.  In:  Gottschlich MM, ed.  The A.S.P.E.N. Nutrition Support 
                                                         Core Curriculum:  A case-based approach – the adult patient.  Silver Spring, MD:  American Society for 
                                                         Parenteral and Enteral Nutrition; 2007;264-276. 
                                                          
                                                         Mehta NM, Compher C, A.S.P.E.N. Board of Directors.  A.S.P.E.N. clinical guidelines:  nutrition support of 
                                                         the critically ill child.  JPEN J Parenter Enteral Nutr.  2009;33:260-276. 
                                                          
                                                         Policy #                                                                         PICU Manual                                                             Page 3 of 3 
                                                                                                                                                                                      Refer to online version – Print copy may not be current – Discard after use