Book contents
- Frontmatter
- Contents
- List of contributors
- Preface
- Part I Basic principles
- 1 Cardiac function, monitoring, oxygen transport
- 2 Shock
- 3 Oxygen therapy
- 4 Central venous access
- 5 Fluid therapy in ICU
- 6 Anaemia and blood transfusion
- 7 Nutrition
- 8 Non-invasive mechanical ventilation
- 9 Principles of IPPV
- 10 Modes of ventilation and ventilatory strategies
- 11 Weaning and tracheostomy
- 12 Vasoactive drugs
- 13 Infection and infection control
- 14 Sedation, analgesia and neuromuscular blockade
- 15 Continuous renal replacement therapy
- 16 Withholding and withdrawing therapy in the ICU
- Part II Specific problems
- Index
7 - Nutrition
Published online by Cambridge University Press: 24 August 2009
- Frontmatter
- Contents
- List of contributors
- Preface
- Part I Basic principles
- 1 Cardiac function, monitoring, oxygen transport
- 2 Shock
- 3 Oxygen therapy
- 4 Central venous access
- 5 Fluid therapy in ICU
- 6 Anaemia and blood transfusion
- 7 Nutrition
- 8 Non-invasive mechanical ventilation
- 9 Principles of IPPV
- 10 Modes of ventilation and ventilatory strategies
- 11 Weaning and tracheostomy
- 12 Vasoactive drugs
- 13 Infection and infection control
- 14 Sedation, analgesia and neuromuscular blockade
- 15 Continuous renal replacement therapy
- 16 Withholding and withdrawing therapy in the ICU
- Part II Specific problems
- Index
Summary
Nutrition
Appropriate nutrition is vital in the critically ill patient. In its absence there will be:
Muscle atrophy and weakness.
Decrease in immune function.
Decrease in wound healing.
Impaired weaning off intermittent positive pressure ventilation (IPPV).
Gut mucosal atrophy.
In the critically ill patient who is markedly catabolic the above may occur in a few days. Nutritional support improves nutritional status but there is little concrete evidence for a beneficial effect on survival. However, promoting ongoing malnourishment must be detrimental to the patient. Certainly more than 10,000 kcal negative caloric balance is associated with a poor outcome in intensive care unit (ICU) patients [1]. There is little evidence that nutritional support can reverse the negative nitrogen balance or catabolism which occurs in the critically ill patient. In which case the purpose of support is to minimise the negative nitrogen balance.
In simple starvation (i.e. non-physiologically stressed), the energy requirements in the first week are chiefly met by protein breakdown to amino acids and subsequent glucose formation via gluconeogenesis. The body adapts to a protein sparing metabolism in starvation, but these changes are absent or opposed in the ICU patient.
In addition:
Sepsis results in a preferential metabolism of fat rather than glucose partly due to inhibition of the enzyme complex pyruvate dehydrogenase.
[…]
- Type
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- Information
- Handbook of ICU Therapy , pp. 80 - 92Publisher: Cambridge University PressPrint publication year: 2006