TPN(total parentral nutrition) and its role in cardiac surgery will be expolred in this presentation.

1. TPN
(TOTAL PARENTAL
NUTRITION)
DR. DHAVAL A. BHIMANI

2. DEFINITION
• PARENTERAL NUTRITION (PN) IS PHARMACOLOGICAL THERAPIES WHERE
NUTRIENTS, VITAMINS, ELECTROLYTES AND MEDICATIONS ARE DELIVERED VIA
THE VENOUS ROUTE TO THOSE PATIENTS WHOSE GASTROINTESTINAL TRACT IS
NOT FUNCTIONING AND ARE UNABLE TO TOLERATE ENTERAL NUTRITION.
• PN IS AN EFFECTIVE MEANS OF SUSTAINING LIFE AND PROMOTING RECOVERY IN
CRITICALLY ILL PATIENT INCAPABLE OF INGESTING, ABSORBING, OR
ASSIMILATING NUTRIENTS.
• SIMILARLY PN IS A LIFE SUPPORTING THERAPY EVEN FOR NON-CRITICALLY ILL
PATIENTS WHO HAVE PRE-EXISTING MALNUTRITION AND FOR NON-STRESSED
BUT HOSPITALIZED PATIENTS WHO ARE UNABLE TO TAKE ORAL INTAKE FOR 5
TO 7 OR MORE DAYS.

3. BASIC PRINCIPAL OF NUTRITION
• AVOID MALNUTRITION. THERE IS NO DISEASE PROCESS THAT BENEFITS FROM
STARVATION.
• IF THE BOWEL WORKS, USE IT. WHENEVER FEASIBLE, ENTERAL NUTRITION (EN)IS
PREFERRED OVER PARENTERAL NUTRITION BUT SAFE AND ADEQUATE
ADMINISTRATION OF NUTRITION IS MORE IMPORTANT THAN THE ROUTE OF
ADMINISTRATION.
• AVOID OVERFEEDING: OVERFEEDING THE PATIENT IS ASSOCIATED WITH
SIGNIFICANT COMPLICATIONS INCLUDING HYPERGLYCEMIA, HEPATIC STEATOSIS
(FATTY INFILTRATION OF LIVER) WITH HEPATIC DYSFUNCTION, ELEVATED
BLOOD UREA NITROGEN, AND EXCESSIVE C02 PRODUCTION.

4. • THE ROUTE, TIMING AND TYPE OF NUTRITIONAL FORMULATION ARE MORE·
IMPORTANT THAN THE SPECIFIC AMOUNTS OF NUTRIENTS SUPPLIED.
• DURING ACUTE STRESS, THE BODY MOBILIZES ENDOGENOUS AMINO ACID AND
ENERGY STORES.
• IT IS NOT POSSIBLE TO MAKE CATABOLIC PATIENTS ANABOLIC. THE ROLE OF
NUTRITIONAL SUPPORT IS TO LIMIT PROTEIN WASTING AND TO SUPPLY
ESSENTIAL AND CONDITIONALLY ESSENTIAL NUTRIENTS.

5. WHY IT IS IMPORTANT TO AVOID
MALNUTRITION?
• MALNUTRITION LEADS TO INCREASED SUSCEPTIBILITY TO INFECTION, POOR
WOUND HEALING, FISTULA FORMATIONS, DELAYED CALLUS FORMATIONS,
PULMONARY COMPLICATIONS (IMPAIRMENT OF RESPIRATORY MUSCLES LEADING
TO REDUCTION OF VITAL CAPACITY AND HYPOXIC VENTILATORY RESPONSE)
DECREASED TOLERANCE TO RADIOTHERAPY AND CHEMOTHERAPY, REDUCE
ENZYME SYNTHESIS, AND IMPAIRED OXIDATION OF DRUGS BY THE LIVER.
• A LONGER RECOVERY PERIOD AND INCREASED DURATION OF HOSPITALIZATION
• POOR QUALITY OF LIFE.

6. GOAL OF PARENTERAL THERAPY
• TO MAINTAIN OR IMPROVE THE NUTRITIONAL STATUS BY PROVIDING ALL
NUTRIENTS (PROTEINS, CARBOHYDRATES, LIPIDS, ELECTROLYTES, MINERALS,
TRACE ELEMENTS AND VITAMINS) FOR ONGOING METABOLIC FUNCTIONS.
• TO MINIMIZE THE DELETERIOUS EFFECTS OF CATABOLISM BY MAXIMIZING
PROTEIN SYNTHESIS, LIMITING BODY PROTEIN BREAKDOWN AND REDUCING THE
RATE OF WEIGHT LOSS.
• TO BOOST UP THE IMMUNE FUNCTION AND TO IMPROVE WOUND HEALING.

7. • TO IMPROVE THE CARDIAC AND RESPIRATORY FUNCTION BY RESTORING THE
GLYCOGEN STORAGE IN CARDIAC AND DIAPHRAGMATIC MUSCLES.
• TO MAINTAIN OR CORRECT ACID-BASE AND ELECTROLYTE DISTURBANCES.
• TO ACCELERATE REHABILITATION AND IMPROVE THE QUALITY OF LIFE.

8. INDICATION FOR TPN
• A. GENERAL INDICATIONS
• INADEQUATE ORAL OR ENTERAL NUTRITION FOR AT LEAST 7-1 O DAYS
• PRE EXISTING SEVERE MALNUTRITION WITH INADEQUATE ORAL OR ENTERAL
NUTRITION
• B. ANTICIPATED OR ACTUAL INADEQUATE ORAL OR ENTERAL INTAKE
• GIT INDICATION LIKE SHORT BOWEL SYNDROME, ENTEROCUTANEOUS FISTULA,
ACUTE PANCREATITIS, ISCHEMIC BOWEL, SMALL BOWEL OBSTRUCTION, PERITONITIS
• MOTILITY DISORDER- PARALYTIC ILEUS
• INABILITY TO MAINTAIN INTEGRITY OF INTESTINAL TRACT- MASSIVE GI BLEED.

9. • C. SIGNIFICANT MULTIORGAN SYSTEM DISEASE
• SIGNIFICANT RENAL, HEPATIC, AND PULMONARY DISEASES OR CRITICAL ILLNESS
(MULTI-ORGAN FAILURE, SEVERE HEAD INJURY, BURNS ETC.), WHICH PREVENTS
ADEQUATE ORAL OR ENTERAL NUTRITION.

10. CONTRAINDICATION FOR PN
• A. GENERAL CONTRAINDICATIONS
• IF ENTERAL NUTRITION MEETS OR EXCEEDS THE CALCULATED NUTRITIONAL
REQUIREMENTS.
• PATIENT WITH GOOD NUTRITIONAL STATUS WHO REQUIRES SHORT-TERM SUPPORT.
• SEVERE LIVER FAILURE, CARDIAC FAILURE, SHOCK AND BLOOD DYSCRASIAS.
• FLUID-ELECTROLYTE IMBALANCES

11. • B. DISEASE SPECIFIC CONTRAINDICATIONS
• AVOID EXCESS USE OF CARBOHYDRATES IN PATIENTS WITH COMPROMISED
PULMONARY FUNCTION AND IN PATIENTS WITH VENTILATOR SUPPORT DURING
WEANING PERIOD, AS IT MAY RESULT IN PRODUCTION OF LARGE AMOUNT OF
CARBON DIOXIDE.
• AVOID LIPID ADMINISTRATION, IF THE TRIGLYCERIDE LEVEL IS MORE THAN 350
MG/DL OR IN PATIENTS WITH SEVERE SEPSIS, MODERATE DEGREE OF JAUNDICE, LOW
PLATELET COUNT ( < 50,000 TO 60,000/ MM) AND ARDS OR SEVERE RESPIRATORY
DISEASE.
• IN PATIENTS WITH HEPATIC ENCEPHALOPATHY AND SEVERE RENAL FAILURE
MODIFIED AMINO ACIDS ARE PREFERRED OVER STANDARD AMINO ACIDS.It is important to remember that parenteral nutrition is not to be
undertaken lightly. It is potentially hazardous and can be dangerous
in inexperienced hands.

12. HOW TO PLAN TPN
• SELECTION OF PATIENT
• CALCULATIONS OF NUTRITIONAL REQUIREMENTS.
• SELECT AND ESTABLISH APPROPRIATE ROUTE OF ADMINISTRATION
• ADMINISTRATION, MONITORING AND AVOIDING COMPLICATIONS PARENTERAL
NUTRITION

13. • SELECTION OF PATIENT:
• NUTRITIONAL SUPPORT IS RECOMMENDED ONLY WHEN POTENTIAL BENEFITS
(IMPROVEMENT IN PROGNOSIS AND QUALITY OF-LIFE) EXCEED THE RISKS.
• ENTERAL NUTRITION (EN) IS PREFERRED OVER PARENTERAL NUTRITION (PN)

14. WHY ??
• MAINTAINS MUCOSAL PROTECTION
• EN SUPPLIES GUT-PREFERRED FUELS (GLUTAMINE, GLUTAMATE AND SHORT
CHAIN FATTY ACIDS) UNLIKE STANDARD PN.
• MORE PHYSIOLOGICAL THE LIVER IS NOT BY-PASSED. SO HEPATIC ABILITY TO
TAKEUP, PROCESS AND STORE THE VARIOUS NUTRIENTS FOR LATER RELEASE ON
NEURAL OR HORMONAL COMMAND IS MAINTAINED.
• PREVENTS CHOLELITHIASIS BY STIMULATING GALL BLADDER MOTILITY.
• LESS COSTLY AND EASIER TO MAINTAIN THAN PN.

15. WHEN IS ENTERAL NUTRITION
CONTRAINDICATED?
• GI CAUSES: SEVERE DIARRHOEA, PARALYTIC ILEUS, INTESTINAL OBSTRUCTION,
SEVERE GI BLEEDING, SEVERE ACUTE PANCREATITIS AND HIGH OUTPUT EXTERNAL
FISTULA.
• CARDIAC CAUSES: HAEMODYNAMIC INSTABILITY, LOW CARDIAC OUTPUT,
HYPOTENSIVE PATIENTS ON MODERATE TO LARGE DOSE OF ALPHA AGONISTS OR IN
CIRCULATORY SHOCK. ENTERAL FEEDING IN HAEMODYNAMICALLY UNSTABLE
PATIENTS CARRIES POTENTIAL RISK OF GASTROINTESTINAL ISCHEMIA.
• LACK OF ACCESS: UNOBTAINABLE SAFE ACCESS TO GASTROINTESTINAL TRACT.
• THE PATIENTS WITH COMPLICATIONS OF ENTERAL FEEDING (I.E. PULMONARY
ASPIRATION, SEVERE DIARRHOEA, AND INTESTINAL LSCHEMIA OR INFARCT
PRECIPITATED BY ENTERAL FEEDING IN PATIENTS WITH ISCHEMIC BOWEL SYNDROME)
SHOULD NOT BE FED BY ENTERAL ROUTE.

16. ADVANTAGES OF PARENTERAL NUTRITION
OVER ENTERAL NUTRITION
• ENSURED, DESIRED VOLUME DELIVERY OF NUTRIENTS WITHOUT THE CONCERNS
OF GASTROINTESTINAL INTOLERANCE OR COMPLIANCE WITH TRANSNASAL
FEEDING TUBES.
• IMPROVED METABOLIC, ELECTROLYTE, AND MICRONUTRIENT MANAGEMENT.
• BETTER ACID-BASE MANIPULATION.
• DRUG DELIVERY CAPABILITIES (HISTAMINE H2 BLOCKERS, METOCLOPRAMIDE,
INSULIN, HEPARIN ETC).
• SO, PN NOT ONLY DELIVERS NUTRITION BUT ALSO REGULATES FLUID,
ELECTROLYTE AND ACID-BASE HOMEOSTASIS.

17. CALCULATIONS OF NUTRITIONAL
REQUIREMENTS.
• ENERGY REQUIREMENTS:-
1. SIMPLE BODY WEIGHT BASED CALCULATION:
REE (KCAL/DAY) = 25 X WEIGHT
2. HARRIS-BENEDICT EQUATION:
REE (MAN) = 66 + (13.7 X W) + (5.0 X H) - (6.7 X A)
REE (WOMEN) = 655 + (9.6 X W) + (1.8 X H) - (4.7 X A)
• W = WEIGHT IN KG H = HEIGHT IN CM A = AGE IN YEARS.

18. SO, TEE = REE X AF X DF X TF
• GUIDELINES FOR ADJUSTMENT IN ENERGY REQUIREMENTS
• AF=ACTIVITY FACTOR
• 1.2 - BED REST , 1.3 - OUT OF BED
• DF=DISEASE FACTOR
• 1.25 GENERAL SURGERY
• 1.3 SEPSIS
• 1.6 MULTIORGAN FAILURE
• 1.7- 1.8- 1.9 - 30-50%, 50-70%,70-90% BURNS, RESPECTIVELY
• TF= THERMAL FACTOR.
• 1.1 - 38°C, 1.2 - 39°C , 1.3 – 40 °C , 1.4 - 41 °C

19. HOW TO PROVIDE ENERGY REQUIREMENTS TO
A PATIENT ON PN?
• APPROXIMATE PROPORTION OF DIFFERENT MACRONUTRIENTS (CARBOHYDRATE,
FAT AND PROTEIN) IN PARENTERAL SOLUTION FOR ENERGY SUPPLEMENTATION
IS AS FOLLOWS:
• 50 - 70% CARBOHYDRATE (1 GRAM DEXTROSE = 3.4 KCAL)
• 20 -30% FAT (1 GRAM LIPID = 9 KCAL)
• 15 - 20% PROTEIN (1 GRAM PROTEIN = 4 KCAL)

20. IMPORTANT NOTE
• USUALLY ONLY NON PROTEIN CALORIES ARE UTILIZED FOR ENERGY CONTENT
OF PN, APPLYING THE THEORY THAT PROTEIN WILL BE USED FOR ANABOLIC
PROCESS RATHER THAN AS AN ENERGY SOURCE.
• IN CLINICAL PRACTICE, USUALLY A MIXTURE OF GLUCOSE AND TRIGLYCERIDES
IS GIVEN IN A RATIO OF APPROXIMATELY 60 TO 70% GLUCOSE AND 30-40% OF
FAT.
• THIS MIXED FUEL NUTRIENT IN STRESSED PATIENTS SIGNIFICANTLY REDUCES
C02 PRODUCTION AND THEREFORE, REDUCES THE RESPIRATORY WORK OF
BREATHING.

21. MONITORING OF PN
• RECORD VITAL SIGNS AT LEAST EVERY 4 HOURS. TEMPERATURE ELEVATION IS ONE
OF THE EARLIEST SIGNS OF CATHETER RELATED SEPSIS.
• PATIENTS SHOULD BE WEIGHED DAILY AT THE SAME TIME EACH MORNING AFTER
VOIDING, ON THE SAME SCALE WEIGHT GAIN MAY INDICATE FLUID OVERLOAD.
• PERFORM SITE CARE AND DRESSING CHANGE AT LEAST THREE TIMES A WEEK, OR
WHENEVER THE DRESSING BECOMES WET.
• PATIENTS RECEIVING PN SHOULD BE MONITORED CAREFULLY TO DE.TECT EARLY
SIGNS OF COMPLICATIONS SUCH AS FLUID OVERLOAD, ELECTROLYTES IMBALANCE,
NUTRITIONAL PROBLEMS OR ALLERGIC REACTIONS.

22. • MONITOR SERUM GLUCOSE LEVELS EVERY 6 HOURS INITIALLY, THEN ONCE A
DAY . WATCH FOR THE SYMPTOMS OF HYPERGLYCEMIA SUCH AS THIRST AND
POLYURIA.
• MONITOR ELECTROLYTE AND PROTEIN LEVELS DAILY AT FIRST, AND THEN
TWICE A WEEK. ALBUMIN LEVELS MAY DROP INITIALLY AS TREATMENT RESTORES
HYDRATION.
• ASSESS LIVER FUNCTION WITH LIVER FUNCTION TESTS, BILIRUBIN, SGPT,
TRIGLYCERIDE, AND CHOLESTEROL LEVELS. ABNORMAL VALUES MAY INDICATE
INTOLERANCE.
• MONITORING RESPONSE TO NUTRITIONAL THERAPY. THERE IS NO SINGLE
CRITERION . WHICH CAN RELIABLY INDICATE EFFECTIVENESS OF PN.
IMPROVEMENT IN CLINICAL STATUS AND VISCERAL PROTEIN CONCENTRATIONS
(E.G. ALBUMIN, PREALBUMIN AND TRANSFERRIN) ARE MOST COMMONLY USED
TO MONITOR NUTRITIONAL STATUS.

23. TERMINATION OF PN
• PN IS THE TEMPORARY METHOD OF NUTRITIONAL SUPPLEMENTATION. THE
ULTIMATE GOAL IS TO RESTART ORAL/ENTERAL FOOD INTAKE AS SOON AS·
GASTROINTESTINAL FUNCTION RETURNS.
• THE TRANSITION FROM PN TO ORAL OR ENTERAL NUTRITION SHOULD BE DONE
GRADUALLY TO AVOID THE DETERIORATION IN NUTRITIONAL STATUS WHEN PN IS
DISCONTINUED.
• PN SHOULD NOT BE DISCONTINUED ABRUPTLY. REDUCE INFUSION RATE TO 50% FOR
1 TO 2 HOURS BEFORE DISCONTINUING PN. SUCH REDUCTION WILL MINIMIZE THE
RISK OF REBOUND HYPOGLYCEMIA.
• IF THERE IS A NEED TO DISCONTINUE PN ABRUPTLY, A 10% DEXTROSE SOLUTION
MAY BE ADMINISTERED FOR A FEW HOURS AND THEN DISCONTINUED TO PREVENT
HYPOGLYCEMIA. ONCE PATIENT IS ABLE TO TAKE 60% OF THE TOTAL ENERGY AND
PROTEIN REQUIREMENTS ORALLY OR ENTERA!LY,. PN MAY BE STOPPED.

24. COMPLICATIONS
Mechanical Metabolic/GI Infectious
First 48 hours Malposition,
hemothorax,
pneumothorax, air
embolism, blood
loss, puncture of
subclavian or carotid
artery
Fluid overload
Hyperglycemia
Hypophosphatemia
Hypokalemia
Hypomagnesemia
Refeeding syndrome
------
First 2 weeks Catheter
displacement
Catheter thrombosis
Catheter occlusion
Air embolism
Hyperglycemic coma
Acid base imbalance
Electrolyte imbalance
Catheter induce
sepsis
3 month onwards Fracture or tear of
catheter,
Air embolism
Essential fatty acid
deficiency,
Vitamin deficiency,
PN metabolic bone
and liver disease.
Tunnel infection
Catheter site sepsis.

25. THANK YOU