Oxygen (O2) consumption as measure of cell number in intrauterine growth failure (IUGF)

Abstract

O2-cons. in the basal state is a measure of the metabolically active tissue mass and, as such, may reflect cell number rather than cell mass. This was tested by comparing conditions which have a different ratio between cell number and cell mass (CNo). 24 patients with IUGF and persistent linear growth failure after birth (PIUGF) were assumed to have a low CNo. 31 patients with growth failure of postnatal onset due to undernutrition, group A, were assumed to have a higher CNo than PIUGF because undernutrition in not rapidly multiplying tissues decreases cell size. 24 patients with growth failure of postnatal onset and congenital anomalies were placed in group B, with unkown relative CNo. Age were 4/12–10 years and height ages <3 years. 37 normal control were <3 years old.O2-cons. for age and height age was significantly lower in PIUGF than all other groups. O2-cons. of groups A and B was not different, i.e. significantly lower than the normal for age and similar to the normal for height age. O2-cons. per body weight was normal in PIUGF and elevated in groups A and B. O2-cons. per weight predicted from height was negatively related to height in per cent of the normal height for age. The regression for PPIUGF was significantly lower than in group A and B. A good correlation was evident only in group A (r = .723). This suggests an increase in metabolically active tissue with increasing degrees of linear growth failure due to undernutrition, which compatible with the known effect of chronic undernutrition on cell size. In concluding therefore that changes in CNo were responsible for this observation, it is suggested that the lower patients with persistent growth failure after birth we apparently singled out cases with “hypoplastic” IUGF.