How Fever,Illness,Infections,Injury affects the BMR?
Any illness or fever caused by an illness influences the metabolic rate. Fevers increase the metabolic rate by about 7% for each degree increase in body temperature above 98.G°F or in other words 13% for each degree above 37°C. During injury or infections there is an increased BMR, and this increase is dependent on the severity of the injury. For example, the BMR may even double with bums of more than 40% of the body sui-face, in severe sepsis, multiple traumas, whereas it may only increase by about 25% in patients with long bone fractures and even less after surgery. But we need to understand that in sick patients who are likely to be in bed, the increase in the BMR due to the stress imposed by the disease may be offset by the decrease in physical activity, such that the total daily energy expenditure may not change drastically.