Parenteral Nutrition

By Dr Kaleem Ullah Bhatti House Surgeon

What is Nutrition?

The taking in and metabolism of nutrients so that life is maintained and growth can take place.

Malnutrition

Definition A disorder of nutrition it may be due

to unbalanced or insufficient diet or to defective assimilation or utilization of foods.

Types Of Nutrition

Following are the types of nutrition Enteral Nutrition Parenteral Nutrition

Parenteral Nutrition

Definition It is administration of nutrition

exclusively through intravenous route bypassing gastrointestinal tract

Indications for parenteral nutrition

Either who are malnourished

Have the potential for developing malnutrition

Are not candidates for enteral support

Indications for Parenteral Nutrition

Parenteral nutrition is usually indicated in the following situations:

Documented inability to absorb adequate nutrients via the gastrointestinal tract; this may be due to:

Massive small-bowel resection / Short bowel syndrome (at least initially)

Radiation enteritis Severe diarrhea ,Steatorrhea Complete bowel obstruction, or

intestinal pseudo-obstruction Severe catabolism with or without

malnutrition when gastrointestinal tract is not usable within 5-7 days

Inability to provide sufficient nutrients/fluids enterally

Persistent GI hemorrhage Acute abdomen/ileus Lengthy GI work-

up requiring NPO status for several days in a malnourished patient

High output enterocutaneous fistula and EN access cannot be obtained distal

to the site.

Parenteral nutrition maybe indicated in the following situations:

Inflammatory bowel disease unresponsive to medical therapy

Hyperemesis gravidarum when nausea and vomiting persist longer than 5 -7

days and enteral nutrition is not possible

Partial small bowel obstruction Intensive chemotherapy / severe

mucositis Major surgery/stress when enteral

nutrition not expected to resume within 7-10 days

Intractable vomiting and jejunal access is not possible

Chylous ascites or chylothorax when EN(with a very low fat formula) does

not adequately decrease output

Assessment Of Nutrition

History Physical ExaminationAnthropometric MeasurementsLaboratory Investigations

Dietary History

It should include: Food habits Quality and quantity of ingested nutrients Appetite and changes in appetite Food intolerance and allergies Chewing or swallowing problems Significant weight loss within last 6 months▪ > 15% loss of body weight▪ compare with ideal weight▪ Beware the patient with ascites/

oedema/amputations

Physical Examination

We will proceed step by step General Appereance Skin and appendages Eyes,Mouth Neurological

Anthropomeric Measures

• Weight for Height comparison• Body Mass Index (<19, or >10%

decrease)• Triceps-skinfold • Mid arm muscle circumference• Bioelectric impedance• Hand grip dynamometry• Urinary creatinine / height index

Biochemical Parameters

Serum Albumins can provide useful information

Low Level Serum Albumin+ raised C-reactive protein

Low level of Serum Albumins+ normal C-reactive

proteins

Rising serum albumins levels

BODY REQUIREMENTS

Caloric Requirement

TEE = REE + Stress Factor + Activity Factor

Rest Energy Expenditure Adults (18-65) 20-30 kcal/kg Elderly (65+) 25 kcal/kg For burns Patients 30-35kcal/kgOther factors: Pregnancy: Add 300 kcal/day Lactation: Add 500 kcal/day Obese or Super obese 15-20 kcal/kg

Stress factor

peritonitis + 15%

• soft tissue trauma + 15%

• fracture + 20%

• fever (per oC rise) + 13%

• Moderate infection + 20%

• Severe infection + 40%

• <20% BSA Burns + 50%

• 20-40% BSA Burns + 80%

• >40% BSA Burns + 100%

Activity Factor

Fluid Requirments

ESTIMATING ADULT FLUID REQUIREMENTS

1. By caloric intake : 1ml/calorie Ex: 1800 calorie diet = 1800 calories x

1ml= 1800ml 2. By body weight and age : Age Fluid requirements 16-55 years 35 ml/kg/day 56-65 years 30 ml/kg/day > 65 years 25 ml/kg/day

COMPONENTS OF PARENTERAL NUTRITION

Macronutrients Micronutrients

Carbohydrate Requirement

Requirement 2g/kg/day 1grams=5kcal/g 40-50 percent of total nutrition

Fat Requirements

Requirement 3 g/kg/day 1 gram= 9kcal/g 30-40 percent of nutrition

Carbohydrate and fat,usually in lipid:carbohydrate ratio of 60:40 or vice versa

Protein/Nitrogen Requirements

Requirement 0.2-0.5g/kg/day 1 gram= 4kcal/g 15-20 percent of nutrition Mild stress 1.0 -1.2 g/kg Moderate stress (most ICU patients)

1.5-2.0 g/kg Severe Obesity 1.5 g – 2.0 g/kg IBW Severe stress, catabolic, burns 2.0

–2.5 g/kg

Nitrogen Balance

Nitrogen Balance = N input - N output

6.25 g protein provides 1 g of nitrogen,as 100grams contains 16 g nitrogen

N input = (protein in g / 6.25) N output = 24h urinary urea nitrogen + non-

urinary N losses

+4 to + 6: Net anabolism +1 to - 1: Homeostasis -2 to – 1: Net catabolism

Electrolyte Daily Requirements

Sodium 70 – 100 mEq/day Chloride 70 – 100 mEq/day Potassium 70 – 100 mEq/day Calcium 10 – 20 mEq/day Magnesium 15 – 20 mEq/day Phosphorus 40-60 mEq/day Acetate 0 – 60 mEq/day

Daily Parenteral Vitamins Supplementation

Vitamin A 3300 IU Vitamin D 200 IU Vitamin E 10 IU Vitamin K - 150 mcg Ascorbic acid 100 mg Folic Acid 0.4 mg Niacin 40 mg Riboflavin (B2) 3.6 mg Thiamin (B1) 3 mg Pyridoxine (B6) 4 mg Cyanocobalamin (B12) 5 mcg Pantothenic acid 15 mg Biotin 60 mcg

Daily Parenteral Trace Element Supplementation

Zinc 2.5-4 mg Copper 0.5-1.5mg Chromium 10-15 mcg Selenium 20-60 mcg Manganese 150-800 mcg

Central Venous Access

It can be achieved either by peripheral line indirectly or central line directly

Every route have its own advantages and disadvantages

Decide either for short time or long time

Short term PN may be provided centrally via the subclavian or internal jugular vein.

Long term access can be achieved by

Peripheral Peripherally Inserted Central CatheterLine (PICC line), which is passed via the antecubital vein

Non Cannulated catheters(Hickman and Groshong line)

PICC line

ADVANTAGES

Bed side technique Avoids complications

of central venous catheter

Avoid multiple venous cannulations

Hyperonic solutions can be given

DISADVANTAGES

Trained personnel is needed

Line blockage Mal position Phlebitis Line sepsis thrombosis

Central Catheter(Non Tunneled)

ADVANTAGES

Central access needed

Multiple lumina can be used in acute emergency

Hypertonic solutions can be given

Can be placed for than 6 weeks

DISADVANTAGES

Inserted in theatre Increase infection rate Multiple complications

Central catheter (Tunneled)

ADVANTAGES

Convenient exit site Long lasting than non

tunnels Hypertonic solutions

can be given

DISADVANTAGES

Removal needs surgical dissection

Catheter related sepsis

Other complications

Once the route is decided then we will calculate daily requirements and proceed

Determine Total Fluid Volume

Determine Non- Caloric needs

Determine Protein requirements

Determine Electrolyte and Trace element requirements

Determine need for additives

Lab Investigations

Full Blood Count Renal Function

Test Ca++, Mg++, PO4

2- Liver Function

Test Iron Panel Lipid Panel Nitrogen Balance

weekly, unless indicated daily until stable, then

2x/wk

daily until stable, then

2x/wk weekly weekly 1-2x/wk

weekly

Complications Of TPN

Mechanical

metabolic

infectious

Mechanical Complications

Related to vascular Access• Pneumothorax• Air embolism• Bleeding• Brachial plexus injury• Catheter malplacement• Catheter embolism• Thoracic duct injury

Related to catheter in situ• Venous thrombosis• catheter occlusion

Metabolic Complications

Electrolyte imbalance

•Hypo/hyperglycemia•Hyponatremia,hypokalemia etc

Hepatic •Hepatic steatosis•Acalculous cholecystitis

Acid Base Disorders

Infectious Complications

Insertion site Contamination

Catheter Contamination

•improper insertion technique•use of catheter for non-feeding purposes•contaminated TPN solution •contaminated tubing

Secondary Contamination

•septicemia

References

Adult Enteral and Parenteral Nutrition Handbook, 5th Ed

Oxford Handbook Of Critical Care Internet