Increased O2 consumption and energy loss in premature infants following medical care procedures.

Oxygen consumption (VO2) and CO2 production (VCO2) were measured continuously for 24 h in 10 premature infants during their ongoing nursing care. Using a flow-through technique, the total VO2 and VCO2 over a given period of time were determined from the area under the O2-and CO2-concentration-time curve of the mixed expired gas. Following chest physiotherapy, heel stick and i.v. needle insertion, there was a significant (p less than 0.01) increase in VO2 and VCO2. When measured for 24 h, the total daily increase of VO2 attributed to these procedures ranged from 2.1 to 11.7% of total daily VO2, equivalent to an estimated energy loss of 0.6-4.1 kcal/kg/day.