This document discusses nutrition and nutritional support for patients. It notes that malnutrition is common in hospitalized patients, especially those with gastrointestinal diseases or postoperative complications, and that malnourished patients have higher risks of complications and death. The aim of nutritional support is to identify at-risk patients and meet their nutritional needs through the most appropriate route to minimize complications. Methods of assessment and artificial nutritional support through enteral or parenteral means are described, along with their potential complications.
2. • Malnutrition is common. It occurs in about
30% of surgical patients with gastrointestinal
disease and in up to 60% of those in whom
hospital stay has been prolonged because of
postoperative complications
• patients who suffer starvation or have signs of
malnutrition have a higher risk of
complications and an increased risk of death
3. The aim of nutritional support is
to identify those patients at risk
of malnutrition and to ensure
that their nutritional
requirements are met by the
most appropriate route and in a
way that minimizes
complications.
5. NUTRITIONAL ASSESSMENT
1. Laboratory techniques:
• serum albumin
• Lymphocyte account ( immune deficiency)
2. Body weight and anthropometry
BMI – defined as body weight in kilograms
divided by height in meters squared
A BMI of less than 18.5 indicates nutritional
impairment and a BMI below 15 is associated
with significant hospital mortality
3. Clinical: subjective global assessment
7. Macronutrient requirements
• Energy :
in the majority of hospitalized patients in whom
energy demands from activity are minimal, total
energy requirements are approximately 1300–1800
kcal day.
• Carbohydrate:
• glucose requirement is about 2 g kg day
• physiological maximum amount of glucose that
can be oxidized, which is approximately 4 mg kg
min, with the non-oxidized glucose being primarily
converted to fat.
8. Macronutrient requirements
• Energy during parenteral nutrition should
be given as a mixture of fat together with
glucose. There is no evidence to suggest
that any particular ratio of glucose to fat
is optimal as long as under all conditions
• the basal requirements for glucose (100–
200 g day) and essential fatty acids (100–
200 g week) are met.’
9. Macronutrient requirements
This ‘dual energy is :
1. minimizes metabolic complications
during parenteral nutrition,
2. reduces fluid retention,
3. associated with reduced carbon dioxide
production
10. Vitamins, minerals and trace elements
• Whatever the method of feeding these are all
essential components of nutritional regimens.
The water-soluble vitamins B and C act as
coenzymes in collagen formation and wound
healing. Postoperatively, the vitamin C
requirement increases to 60–80 mg day.
Supplemental vitamin B12 is often indicated in
patients who have undergone intestinal
resection or gastric surgery
11. ARTIFICIAL NUTRITIONAL SUPPORT
• The indications for nutritional support
are simple any patient who has sustained
5–7 days of inadequate intake or who is
anticipated to have no intake for this
period should be considered for
nutritional support.
• The provision of nutritional support is
not specific to certain conditions or
diseases.
12. Enteral nutrition
• The term ‘enteral feeding’ means
delivery of nutrients into the
gastrointestinal tract. The alimentary
tract should be used whenever possible.
• This can be achieved with oral
supplements (sip feeding) or with a
variety of tube-feeding techniques
delivering food into the stomach,
duodenum or jejunum
13. Sip feeding
Commercially available supplementary sip
feeds are used in patients who can drink
but whose appetites are impaired or in
whom adequate intakes cannot be
maintained with ad libitum intakes. These
feeds typically provide 200 kcal and 2 g of
nitrogen per 200 ml carton
14.
15.
16. Tube-feeding techniques
• Enteral nutrition can be achieved using
conventional nasogastric tubes (Ryle’s), fine-
bore feeding tubes inserted into the stomach,
surgical or percutaneous endoscopic
gastrostomy (PEG) or, finally, post-pyloric
feeding utilizing nasojejunal tubes or various
types of jejunostomy
• Conventionally, 20–30 ml are administered
per hour initially, gradually increasing to goal
rates within 48–72 hours.
17. Tube-feeding techniques
• In most units feeding is discontinued for
4–5 hours overnight to allow gastric pH
to return to normal. There is some
evidence that this might reduce the
incidence of nosocomial pneumonia and
aspiration.
• Tube blockage is common. All tubes
should be flushed with water at least
twice daily
18. Complications of enteral nutrition
1. Tube-related
■ Malposition
■ Displacement
■ Blockage
■ Breakage/leakage
■ Local complications (e.g. erosion of
skin/mucosa)
20. Complications of enteral nutrition
3. Metabolic/biochemical
■ Electrolyte disorders
■ Vitamin, mineral, trace element
deficiencies
■ Drug interactions
4. Infective
■ Exogenous (handling contamination)
■ Endogenous (patient)
21. Parenteral nutrition
• Total parenteral nutrition (TPN) is defined as
the provision of all nutritional requirements
by means of the intravenous route and
without the use of the gastrointestinal tract.
• The most frequent clinical indications relate to
those patients who have undergone massive
resection of the small intestine, who have
intestinal fistula or who have prolonged
intestinal failure for other reasons.
23. Complications of parenteral nutrition
1. Related to nutrient deficiency
■hypoglycaemia/hypocalcaemia/hypophosphat
aemia/hypomagnesaemia (refeeding syndrome)
■ Chronic deficiency syndromes (essential fatty
acids, zinc,mineral and trace elements)
Related to overfeeding
■ Excess glucose
■ Excess fat:
■ Excess amino acids:
24. Complications of parenteral nutrition
2. Catheter-related sepsis
■ Possible increased predisposition to systemic
sepsis Related to line
■ On insertion: pneumothorax, damage to
adjacent artery, air embolism, thoracic duct
damage, cardiac perforation or tamponade,
pleural effusion, hydromediastinum
■ Long-term use: occlusion, venous thrombosis