NUTRITIONAL SUPPORT IN SURGICAL PATIENTS M K ALAM MS ; FRCS Professor of Surgery.
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Transcript of NUTRITIONAL SUPPORT IN SURGICAL PATIENTS M K ALAM MS ; FRCS Professor of Surgery.
ObjectivesThis presentation will explain:
•The need for nutritional support
•Consequences of malnutrition
•Methods of assessing malnutrition
•Types of nutritional support & its indications
• Routes of providing nutritional support
•Complications
Definition
Nutritional support is adjuvant therapy used to
support the surgical patients until they are able
to sustain themselves with adequate spontaneous
nutrition by mouth.
• Malnutrition in hospitalized patients is common
• Up to 50% may have moderate malnutrition
• Malnutrition increases morbidity and mortality
• Damaging effects on psychological status, activity level and appearance
• Prolongs hospital stay
ENDOGENOUS ENERGY STORES CARBOHYDRATE - GLYCOGEN
• Just enough to last one day
• Liver- 400 kcal
• Muscle- 1600 kcal -- not readily available • Essential for RBC, WBC, bone marrow, eye , renal medulla &
peripheral nerves
• Brain- normally uses glucose, switches to fat in starvation • 1 Gm. = 4 kcal
ENDOGENOUS ENERGY STORES FAT- ADIPOSE TISSUE
• Largest fuel reserve
• 120,000 kcal in a 70-kg man
• 1 Gm. = 9kcal
• Survival during starvation depends upon the amount of endogenous fat reserve
ENDOGENOUS ENERGY STORES PROTEIN
• Lean body mass- 13 Kg in a 70 Kg man
• 30,000 kcal energy store
• Inefficient source of energy
• Used for essential nitrogenous substances for maintenance and growth
• Synthesis requires non protein calorie source
SIMPLE STARVATION
↓ energy expenditure
↑ use of fat for fuel
↑ lipolysis
↓ nitrogen loss
↓ glucose use by brain*
* RBC, WBC, renal medulla, neurons, muscles & intestinal
mucosa supply maintained
POST-SURGERY STARVATION
↑ hormonal stimulation
↑ cellular activity
↑ metabolic rate
↑ energy expenditure
↑ gluconeogenesis
↑ protein breakdown
↑ nitrogen loss
↑Lipolysis
Aim of nutritional support measures
• The provision of nutrients with therapeutic intent
(prevent / reverse the catabolic effects of disease or injury).
• Identify in a timely manner patients in need of nutritional support
• Provide nutritional requirements by most appropriate route to minimise complications
MAIN CONSIDERATIONS IN NUTRITIONAL SUPPORT
• Which patient requires nutritional support
• Select the appropriate substrate
• Obtain and maintain access for delivery
ASSESSMENT OF NUTRITIONAL STATUS
• History :
Altered oral intake
Unintentional weight loss ( 10-15% in 4-6 months)
• Physical examination:
Body weight / BMI = wt. in kg/ height in m² ( normal- 18.5-24.9)
Mid arm muscle circumference <60% ( M 25.5 cm, F 23 cm )
Triceps skin fold <60% ( M 12.5mm, F 16.5mm )
ASSESSMENT OF NUTRITIONAL STATUS
Laboratory evaluation: Complete blood count Lymphocyte count < 1800/cmm Serum albumin < 30G/L
Immune competence: Delayed cutaneous hypersensitivity to intra-dermal antigens
Functional evaluation: Ability to do daily functions, hand grip
PREOPERATIVE NUTRITIONAL SUPPORT
Improves outcome in severely malnourished
If possible, delay surgery
5-7 days nutritional support
Avoid tumor feeding: limit calorie & protein to match need
Continue nutritional support postoperatively
ASSESSMENT OF NUTRITIONAL REQUIREMENTS
Optimal nutrition should provide adequate requirements of :
Calories- Carbohydrate & fat
Protein
Water
Electrolytes
Trace elements
Vitamins
Energy requirements in adults
Energy : Uncomplicated patients- 25 Kcal/ kg/ day
Complicated/ stressed pts. 30-35 Kcal/kg/day
Energy source : Carbohydrates 70- 80 %
Lipids 20 %
• Carbohydrates: Predominant form used- dextrose
Optimal oxidation @ 4-5mg/kg/min.
• Lipids: 20% of total calories
Lipid emulsion mixed with other element “3 in 1”
Electrolytes:*
Sodium - 1 - 1.5 mEq / kg /day
Potassium 0.7 - 1 mEq/ kg/ day
Calcium 0.2-0.3 mEq/ kg/ day
Magnesium 0.35-0.45 mEq /kg /day
* adjusted daily
Trace elements Vitamins
Fluid requirements
100 ml/kg/day – first 10 kg body wt.
50 ml / kg /day- for next 10 kg
20 ml / kg /day- for each additional kg
1 ml of water / cal. / day
Adjust in patients :
- who cannot tolerate large volume
- additional fluid loss
- febrile or septic
ROUTES USED FOR NUTRITIONAL SUPPORT
Enteral nutrition:
Providing liquid formula diet in to a functioning
GIT to maintain or improve nutritional status
Parenteral nutrition:
Delivering predigested nutrients directly to venous system
Mixed ( enteral + parenteral ):
Tolerate low amount of enteral, weaning from parenteral
Routes of enteral feeding
Nasogastric tube feeding – for short periods
Fine bore nasoenteric tube- positioned in stomach, duodenum, jejunum, better tolerated
Gastrostomy/ jejunostomy– surgical/ endoscopic / radiologic, neurological diseases,
head/ neck carcinoma,
major upper GIT surgery
Enteral feeding
Intermittent bolus- suitable for stomach feeding
Continuous - suitable for duodenum/ jejunum feeding
Initiate at a slow rate, advance as tolerated
Initially dilute feeds, gradually advance to full strength
Feeding in semi-upright position particularly for stomach feeds
Maintain this position for 2 hours after feeds
Aspirate (stomach feeding) before next feeding.
If >150ml, delay next feed.
Advantages of enteral feeding
Simplicity Greater availability Lower cost Well tolerated Maintains gut integrity Fewer complications
Contraindications to enteral feeding
Intestinal obstruction Paralytic ileus High output entero-cutaneous fistula Short bowel syndrome Severe acute pancreatitis Malabsorption
Complications of enteral feeding
Mechanical: tracheobronchial intubation, erosion
blockage, displacement, bowel perforation
Metabolic: Fluid/ electrolyte imbalance, hyperglycemia
Refeeding / overfeeding syndromes
Gastrointestinal: Diarrhea, vomiting, pain
Pulmonary: Aspiration
Infection: Tube site
Total parenteral nutrition- TPN
Delivering predigested nutrients via hyperosmolarsolution into venous system
CVN ( central venous nutrition ) : Subclavian / Internal jugular,
Catheter tip in SVC Most commonly used
PVN ( peripheral venous nutrition ): Solution of lower calorie, lower dextrose and higher lipid Suitable for 7-10 days feeding
TPN - Indications
Non-functioning GIT
Short bowel syndrome
Intestinal fistula
Severe pancreatitis
Intractable vomiting/ diarrhea
Severe inflammatory bowel disease
Developmental anomalies
Multiple organ failure
Sever malnutrition ( unable to take orally )
TPN - Administration
Check all laboratory values before starting
Nutrients given as 3in1 or 2+1
Vitamin k given separately
Heparin & insulin can be added
Start with 1 L , increasing to desired level as tolerated
Monitor- CBC, electrolytes, glucose , urea, creatinine, Ca., Mg., phosphorus, bilirubin, coagulation profile, ALP, ALT,AST
Best managed by nutritional support team
Home TPN
Long term nutritional support
Majority have malignancy
Special catheter- e.g. Hickman
Subclavian vein through subcutaneous tunnel
Support system
Complications of TPN
Catheter related: Vessel injury, thrombosis,
Haemo/ pneumothorax,
Brachial plexus injury, air embolism, sepsis
Metabolic: Hyperglycemia, hypoglycemia, Hypertriglyceridemia, fluid & electrolyte disturbance, Hyperosmolar syndrome, steatohepatitis,
Refeeding and overfeeding syndromes
Others: Cirrhosis, acalcular cholecystitis,
Gallstone, osteomalacia