Objective: To determine whether skin and subcutaneous blood flow measurements using a novel laser Doppler flow meter are useful for evaluating the cardiovascular status of very low birth weight (VLBW) infants during the early postnatal period.
Methods: In eight VLBW infants and eight non-VLBW infants born at Tokyo University Hospital between May 2007 and April 2008, forehead and lower limb skin blood flows were measured continuously for 72 h. Data were averaged every 8 h, and the t-test was used for analysis.
Results: In VLBW infants, forehead blood flow started to increase from the start of measurement to 32 h (16.6 +/- 3.9 ml/min vs. 24.1 +/- 2.1 ml/min; p = 0.002 compared with 8 h) and remained constant thereafter. Lower limb blood flow increased rapidly after 24 h (22.2 +/- 5.5 ml/min vs. 29.5 +/- 5.0 ml/min; p = 0.002 compared with 8 h) and continued increasing thereafter. In contrast, blood flows remained constant in non-VLBW infants.
Conclusions: The results showed that skin and subcutaneous perfusion in VLBW infants increased spontaneously at around 24 h. Differences in blood flow changes between VLBW and non-VLBW infants demonstrate that these parameters successfully identified physiological changes in tissue perfusion in VLBW infants.