Rest energy

Matter itself has energy, called rest energy. Wliat distinguishes matter-energy from other forms of energy is that all matter has inertia and is subject to the force of gravity when at rest as well as when in motion. Inertia measures the resistance of an object to being accelerated by a force, and the inertia of an object at rest is proportional to its mass. 

Wlieii very heavy nuclei, such as those of uranium and plutonium, are split into lighter nuclei having less total mass than the very heavy nuclei, energy is released. The process is called nuclear fission. In either nuclear fission or nuclear fusion, much of the convened rest energy emerges as kinetic energy, heat, and light. 

Pair production, in which the photon is annihilated in a nuclear interaction giving rise to an electron-positron pair, which carries the energy of the photon less twice the rest energy of the electron. 

Equations are available to estimate resting energy expenditure (Table 57-6). The result should be multiplied by a factor to correct for stress or activity level based on clinical judgment. 

The present chapter deals with calculations associated with calories, nitrogen, protein-calorie percentage, parenteral hyperalimentation, and resting energy expenditure (REE) calculations including REE assessments for geriatric and pediatric populations. 

Note The resting energy expenditure (REE) is also referred to as basal energy expenditure and abbreviated as BEE. 

TABLE 11.2. Formulae for Resting Energy Expenditure (REE) Calculations. 

Table 2.4 Empirical formulae for the calculation of resting energy expenditure of men and women with worked examples Harris Benedict (1919) for adults...

Table 2.7 Percentage increase in resting energy expenditure in trauma, fracture, sepsis, burns or fever...

Condition Percentage increase in resting energy expenditnre... 

Table 2.8 Metabolic rate of different organs or tissues in an adult human and contribution of the different organs and tissues to whole-body resting energy expenditure, (REE) in an adult male, female and a six month old child...

The Na ion concentration within the cell is maintained low, due to activity of an enzyme known as the Na+/K+ ATPase. This enzyme/carrier is present in the plasma membrane. It is an antiport system that transports three Na+ ions out of the cell and two K+ ions into the cell, for each molecule of ATP that is hydrolysed (Figure 5.10). It is responsible for maintaining a low Na+ ion concentration but a high K+ ion concentration within the ceU. Its constant activity in many it not all cells requires constant ATP hydrolysis, which accounts for more than 10% of the resting energy expenditure of an adult. 

The quantitative importance of each pathway varies from one tissue to another and from one protein to another. Although hydrolysis of the peptide bonds does not involve ATP, the various processes of protein degradation require considerable expenditure of energy, possibly more than is required for protein synthesis. It is not suprising, therefore, that protein turnover contributes at least 20% to resting energy expenditure (basal metabolic rate). 

MJ - the highest level that has ever been reported. It is Peripheral fatigue about seven times the resting energy expenditure of normal adult males (see Table 2.4). 

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