Definition: is a nutritionally adequate hypertonic solution consisting of three primary macronutrients and some micronutrients that is called “mixed fuel source”.
The 3 Macronutrients:
1.Carbohydrates – the primary source of energy in the body – 40 to 60% of daily caloric requirements & is essential to Central Nervous System function. The most common source is Dextrose and based on metabolic needs of the patients.
2. Lipids – or Fat Emulsions – are long chain triglycerides from vegetable oil (satflower or soy beans oils) are rich in essential & non essential amino acids which is important in the maintenance of connective tissue integrity and prevention of fatty acid deficiency. They are available in 10%, 20%, 30%, solutions. The dose is 0.5 to 1gm./kg/day up to 30% of patients caloric intake.
3. Amino Acids – to maintain structure & facilitate wound healing. Protein is provided as a mixture of essential and non essential crystalline acids with concentration ranging from 5% to 15% standard approximately 505 amino acids & 50% non essential plus semi essential amino acids. Hepatic failure or hyper catabolic condition with formulas that will reduce the incidence of hepatic encephalopathy.
1. Vitamins – unfortunately the US recommended dietary allowance requirements do not apply to parenteral nutrition for the following reason.
a. Liver & GI – absorption process are passed which is eliminated thru the urine without being utilized.
b. Many diseases after the guts ability to absorb fat soluble vitamins & Vit. B12.
c. many nutrients adhere to the plastic tubing & IV solution bags or are destroyed by light & O2 exposure like Vit. A. before reaching the blood stream.
Only Vit. K can be added unless contraindicated.
2. Trace Elements
3. Electrolytes contain Na, Cl2, K, Mg. Ca, & PO4.
When oral or enteral nutrition is not possible or when absorption or function of the gastrointestinal tract is not sufficient to meet the nutritional needs of the patients.
The following diseases are:
1. Severe hemorrhagic pancreatitis
2. Necrotizing entero colitis
3. Prolonged ileus 7 distal bowel obstruction
Other diseases that doesn’t warrant aggressive nutrition support an alternative form of nutritional therapy is suggested because enteral nutrition is recommended to maintain gut integrity & function.
1. Assess nutritional needs of the patient.
2. Check pattern of weight loss or gain & I & O.
3. Check physicians order for TPN, noting additives & rate of infusion.
4. Compare container of TPN against physicians order to ensure that it is correct.
5. Assess patient knowledge of TPN & need for patient teaching.
1. TPN solution (prepared by the pharmacy)
2. IV tubing’s with filter
3. Infusion pump
4. TPN dressing kit as per hospital protocol.
5. Sterile gloves & mask
6. Blood glucose monitoring equipment.
PARENTERAL NUTRITION PROCEDURE
1. Central Venous Line – is the route of choice because it allows the patient the greatest freedom of movement without disturbing the insertion site. It should be in correct position as seen in the CXR & whether pneumothorax occurred during insertion.
2. Confirm correct solution is running at ordered rate. Check expiration date of solution. Use infusion pump and regulate the flow rate.
3. Inspect tubing & catheter connector for leaks or kinks. Tape all connections.
a. Leaks – patient will not received prescribed volume & entry site of bacteria.
b. Kinks – can cause obstruction & clotting the catheter.
4. Inspect insertion site of infiltration , thrombophlebitis or drainage. If present notify physician.
a. Physician may order to remove
b. If suspected infection catheter tip
send for C/S.
5. Monitor V/S – elevated temperature may indicate catheter related sepsis.
6. Assess for symptoms of air embolism:
a. decreased level of consciousness
d. chest pain
NOTE: if suspected – lay patient on left side with head in trendelenburg position – lying on the left side may prevent air from flowing into pulmonary vein. Lying in trendelenburg increases intrathoracic pressure which decreases the amount of blood pulled into vena cava during inhalation.
7. Use TPN line only for administration of TPN & lipids. Do not use the line for any reasons. To minimize breaks in integrity of line to prevent infection.
8. Perform test for glucose every 6hrs. Notify physician for abnormal. Hyperglycemia patient may need insulin to help metabolize glucose or maybe an early indication of sepsis.
9. Monitor lab test of electrolytes BUN, B.S. as ordered & report abnormal findings to prevent complications & to treat them immediately.
10. Maintain accurate record of I & O to monitor fluid balance.
11. Weigh the patient daily & record.
12. Inspect dressing every shift for drainage & intactness. Change whenever loose or moist at least every 48hrs. To prevent infection & patient comfort.
CHANGING OF TUBINGS & DRESSINGS
1. Wash your hands
2. Cross check new solution with Drs’ order., expiration date. TPN should be used with in 24hrs. of preparation .
3. Attach sterile tubing & filter.
4. Prime tubing to avoid air.
5. Place patient in supine to decrease pressure in vena cava to reduce the risk of embolism when catheter disconnected.
6. Don a mask. Ask the patient to turn head facing opposite direction of insertion site & not to cough or talk during dressing changed.
NOTE: Place mask on patient if he/she cannot cooperate because insertion site must be protected from microorganism from the nurse or patients nose & mouth.
7. Don gloves to protect nurse from secretion.
8. Remove old dressing & discard carefully.
9. Inspect insertion site for redness, drainage & swelling.
10. Remove gloves.
11. Wash your hands
12. Open sterile supplies & place on the table.
13. Put on sterile gloves
14. Cleanse insertion site aseptically for 2 mins. With betadine. Allow to air to dry.
15. Cleanse connection catheter & tubing’s with betadine.
16. Loosen tubing at catheter hub.
17. Ask patient to hold breath & bear down (valsava) while you quickly disconnect old tubing & attach new tubing to catheter hub.
18. Tape all connection to prevent accidental connection of tubing.
19. Place transparent semi permeable dressing over insertion – opsite. So you can assess easily without manipulating the dressing.
20. Label dressing & tubing with date & name.
21. Adjust flow rate per Dr’s order.
22. Document amount infused on I & O record.
Note: Lipid solutions are isotonic which helps reduce the osmolality of high Dextrose concentration when mix in 3 in 1 admixture because of the expense of the equipment needed to compound lipids into TPN solution they are infuse separately.
1. Check the solution against Dr’s order – inspect solution for separation of emulsion into layer or forth. Do not use if present may contaminated or spoiled.
2. Wash hands – to prevent spread of microorganism .
3. Use filter no smaller that 1.2um, which can reduce the incidence of particles & air being transfused can cause pulmonary embolism.
4. Cannula g. 18 or 20
5. Identify patient – correct patient is important for medication administration.
6. Adjust flow rate to infuse 1.0ml/min. for children. Monitor V/S watch for adverse reaction.
7. If no adverse reaction occur adjust the flow rate – adult 500ml. 4 to 6 hrs., children up to 1gr. / kg. over 4 hrs.
COMPLICATION OF PARENTERAL NUTRITIONS
Divided in 4 Main Categories:
1. Gastrointestinal – with lipid infusion related to the infusion amount & flow rate.
a. Hepatic steatosis (fatty liver)
b. Intrahepatic & extrahepatic cholestasis. (suggestion of bile flow)
c. Cholelithiasis (formation of gall)
d. Gastrointestinal atrophy
NOTE: that’s why if not contraindicated oral & enteral feeding should be started ASAP.
2. Mechanical Complication:
a. CVP insertion – trauma to the vessels- Pneumothorax.
b. Catheter occlusion – clots, breakage,
Signs and symptoms
a. Vague head
b. Eye swelling on affected site
c. Thrombosis – traumatic catheter insertion.
d. Venous air embolism – usually during line connection changes.
a. Chest pain
Note: CXR should be taken.
3. Metabolic Complications
a. Check each bag of TPN solution for accuracy
b. Infusion pump
c. Monitoring patients response to therapy to prevent metabolic complication, such as hypoglycemia, hypokalemia, hyperglycemia , hypomagnesium, hypocalcemia & hypo many of metabolic disturbances with fluid imbalance may lead to re – feeding syndrome
– slightly elevated BS – can impairthe function of lymphocytes – immuno suppression & risk of infection.
– Can reduce neutrophil chemotaxis & pagocytosis for short term infection
– In kidney – osmotic diuresis used to dehydration & electrolyte imbalance.
NOTE: When new TPN solution is temporarily unavailable, administration of 10% Dextrose in H2O to prevent rebound hypoglycemia. In addition , if a solution is behind schedule it is not recommended that the infusion rate be increased to make up time; this may cause sudden metabolic fluctuations & fluid overload.
b. Re- feeding Syndrome – Where a patient may be severely malnourished characterized by:
1. rapid changes in electrolytes, PO4, K, Mg, Ca, BS.
2. Volume status with in hours to days.
1. Correction of pre – existing glucose & electrolytes abnormalities before initiation of nutritional therapy.
2. Total volume & rate are titrated overload & potential cardiac decompensation.
3. I & O
4. Daily weight
a. Solutions, indwelling CVP- prime sites of infection.
b. Break – Indus of infection then progress to systemic infection if unchecked.
c. TPN – prepared by pharmacist under a lunar film hood to insure a particle – free environment.
d. Hubs should be covered with tape as a reminder no additional solutions or medications are to be added.
6. External tubing should be changed every 24hrs. With the first bag of the day.
7. Dressing should be changed 48hrs. Using opsite adhesive for easier observation of catheter site.
Terminating Parenteral Nutrition
-Taping or cycling the TPN to those patient who are able safely to resume oral & enteral nutrition that the caloric count is ascertain that the patients’ nutritional needs are being met.
– infusion rate is decreased by half for 30 to 60 min. to allow the plasma glucose response & prevent of rebound hypoglycemia.
NOTE: Check BS with in 30 to 60min. To identify the BS level of the patient.