Nutrition in Surgery Flashcards
What is nutrition and nutrient?
Nutrition – The process of utilizing exogenous substances for the production of energy and the synthesis of new tissues.
Nutrient is a substance that is consumed as part of the diet to provide a source of energy, material for growth or their regulation e.g CHO, protein, fat, vitamins & minerals
NUTRITION is an essential component for peri-operative care of surgical patients
Resting energy expenditure (REE)
the energy expended by a person at rest in a thermoneutral environment.
REE in newborn 55Kcal/kg/day, in adult 20-30Kcal/kg/day
What is the Difference between REE and BMR?
REE and BMR usually differs by less than 10% but REE is higher because it include energy expenditure at mental activity and other expenditure
What is the Basal Requirement?
50% - CHO(1g of CHO -4kcal)
35% - Fats(1g of fat -9kcal)
15% - Proteins(1g of protein-4kcal)
These requirements are altered after surgery, trauma or
during infections
What is the daily nuritional requirement?
Daily Requirement
Calories:
Adult: 25-35kcal/kg: 2200-2500kcal/day.
Newborn/infants: 90-120kcal/kg/day
Protein 1-1.5g/kg/day
Nitrogen -0.2g/Kg/day
Vitamins:
Vit A – 5000iu wkly
Vit k – 5-10mg wkly
Vit C – 60-80mg/day
Vit B12 – 500mcg wkly
Folic acid 3-6mg/day
What is the daily requirement for Minerals and Trace elements?
Zinc – 5mg/day
Cu – 0.5-2.00mg/day
Mn – 70-150mcg/day
Cr – 40mcg/day
Se – 70-150mcg/day
What are the fat solcuble and water soluble vitamins?
Where is Vit. B12 absorbed?
Where is Folic acid absorbed?
Fat soluble vitamins –A,D,E,K
Water soluble vitamins –B and C
Vit B12 absorbed in the terminal ileum
Folic acid is absorbed in the duodenum
What are the RISKS ASSOCIATED WITH MALNUTRITION?
-impaired wound healing
Impaired immunity
Wound infection
Impaired coagulation
Reduced muscle strength, respiratory function
Post op fatigue
Pathophysiology of Starvation
The energy requirement is increased in catabolic states such as surgery, trauma
Major elective abdominal surgeries or trauma by 10-30%, generalized peritonitis 15-50%, sepsis 50-80% and burns 80-200%
If these requirements are not met by exogenous supplement, they will be provided from endogenous alternative ways to the deterrent of the body
In Starvation- 1st 12hrs previous meal utilized and within 24 hrs body glucose store is depleted. after 24hrs fatty acids and amino acids are being broken down (gluconeogenesis)
Obligate use of glucose (the CNS others; rbc, wbc, fibroblast, proximal convulated tubules)
Brain and nervous tissue requires 120g of glucose /day while other obligatory users require 40g of glucose/day
What is malnutrition?
There is lack of nutrient in appropriate proportions
Important determinant of surgical outcome
What are causes of malnutrition?
Decreased intake
Decreased absorption
Increased losses
Increased utilization
What are the causes of malnutrition via decreased intake?
- Anorexia: liver dx, cancer
- Neurological disorders
- Brain surgery
- Head injury
- Coma
- Maxillofacial surgery
What are the causes of malnutrition via decreased absorption?
- Malabsorption syndrome-biliary or pancreatic dx
- Massive bowel resection
- Short bowel syndrome
- GIT fistula (High output
- GI obstruction (Oesophageal tumour,
- Oesophageal stricture, Achalasia Cardia,
- Gastric tumour, Pyloric stenosis)
- Ulcerative Colitis, Crohn’s disease
- GIT anomalies in infants
- Acute radiation enteritis
- prolonged ileus after major surgery
Causes Hypercatabolic state (increase utilization):
- Major burns
- Polytrauma patient
- Sepsis
Nutritional Assessment
- Clinical
- anthropometry
- Laboratory evaluation
ASSESSMENT OF NUTRITIONAL STATUS: History
Weight loss
History to suggest inadequate intake
Lack of food: 24-hr dietary recall
Eating pattern, dietary restrictions
Anorexia: liver disease, sepsis, cancer
History to suggest increased losses
Persistent vomiting
Chronic diarrhoea
Enterocutaneous fistula e.t.c
How is Nutritional Status assessed?
Physical Examination:
- Skin and fluffy hair/hair loss , loose flabby skin, oedema.
- Pallor, muscle wasting (eg loss of thenar muscle)
- peripheral oedema
- peripheral neuropathy
* CVS; displaced apex beat , haemic murmurs
* Abdomen; stomas, fistula, abdominal masses, hepatomegaly
* Rectal examination; perineal fistula, pale stools
* Nervous system; neuropathies
Normal Anthropometric measurement
- weight, Height
- BMI (19-24.9kg/m2)
- Skin fold thickness (using skin fold caliper) – M-10mm,F – 13mm
- Mid upper arm circumference - M ->25cm ,F- >23cm
- waist –hip ratio –M – <0.94 , F- <0.8
How to measure organ function?
- handgrip dynamometry
- test of respiratory function
Investigations to measure nutriotional status
- Full Blood Count-reduced Hb, reduced total lymphocytes count(<1500/mm3)
- Mantoux test (anergy)
Normal Serum Protein Concentration
- Albumin(g/dl) - < 35g/L (t1/2 -14-21 days),assess nutrition over previous 21 days
- Transferrin (mg/dl)- t1/2 – 7days
- Thyroxin-binding pre-albumin-t1/2 -3-5days
- Retinol-binding protein – assess nutritional status over 12hrs
What are the INDICATIONS FOR NUTRITION SUPPORT IN MALNUTRITION?
- Resent unintentional loss of weight more than 15%.
- Unable to eat for ˃5days (e.g. post abdominal surgery)
- Significant deficit in hand dynamometry
- Serum albumin less than 3g/dl.
- Serum transferrin less than 200mg/dl.
- Skin anergy.
What are Protein Requirements for surgery?
Number of non-protein (kcal) given should be a ratio of nitrogen intake 150 - 200kcal:1nitrogen.
1g nitrogen = 6.25g protein.
* Malnourished (not stressed)
1-2g protein/kg/day.
* Postop – no organ failure
1.2-1.5g/kg/day.
* Severely catabolic – no organ failure
1.5-2g/kg/day.
What are the various routes of administration
- Enteral
- Parenteral
