[Energy metabolism of ALS patients under mechanical ventilation and tube feeding]

We studied the energy metabolism of ALS patients under mechanical ventilation and tube feeding. Gas exchanges (O2 and CO2 content in expiratory and inspiratory gas) were measured all day long by DELTATRAC (Datex, Finland) in 11 ALS patients, and energy metabolism during 24 hours was calculated according to the next formula; 5.67 VO2 + 1.60 VCO2-2.17 UN (VO2; O2 consumption l/min, VCO2; CO2 production l/min, UN; urea nitrogen excretion in urine g/day). All patients were clinically stable under continuous mechanical ventilation and tube feeding, and did not have any infection such as pneumonia. The patients were 23-70 years old (mean 49.3), and had total clinical courses of 3-12 years (mean 7.1), and 2-8 year-long courses under mechanical ventilation (mean 4.6). They were classified into the next 3 groups: group I; totally locked-in state (2 patients), group II; complete tetraplegia (6 patients), group III; incomplete tetraparesis (3 patients). Basal metabolic rate (BMR) of each patient was also calculated from Harris-Benedict's formula; male = 66.47 + 13.75W + 5.0H - 6.76A, female = 665.10 + 0.567W + 1.85H - 4.68A (W; weight kg, H; height cm, A; body surface area m2). And the changes of the body weight by month were examined retrospectively in 26 ALS patients with at least 2 year-duration under mechanical ventilation, which include the previous 11 patients. The calorie consumption of 24 hours were 783.3 kcal (group I), 875.3 (group II), 974.9 (group III), which were all lower than BMR (I; -26.8%, II; -17.6%, III; -11.3%).(ABSTRACT TRUNCATED AT 250 WORDS)