INTRODUCTION: We examined whether the bedside SensiCath Blood Gas Monitoring System could reduce both blood loss and the time needed to make ventilator-setting changes in a population of very low birth weight (VLBW; <1,500 g) infants. MATERIAL AND METHODS: A prospective, group sample trial was conducted on ventilator-dependent newly born VLBW infants. The trial was unblinded due to the nature of the device and parental consent was obtained before study enrollment. A total of 44 patients were studied. RESULTS: There was no difference (mean +/- SD) between the SensiCath group and controls with respect to birth weight, gestational age, pH, PCO(2), PO(2) or Apgar at 5 min (median 6, both groups). The amount of blood loss for arterial blood gas (ABG) measurement alone was less in the SensiCath group compared to the control group (1.2 +/- 0 ml vs. 6.7 +/- 2.4 ml, p < 0.001) and the total blood loss was also less in the SensiCath group (8.1 +/- 5 ml vs. 10.5 +/- 6.3 ml, p < 0.001), but there was no significant difference between each group in the amount of blood transfused. The time to obtain ABG results and to make a ventilator change was shorter in the SensiCath group compared to control (2 +/- 0 vs. 26 +/- 21 min, p < 0.001). DISCUSSION: Use of the modified SensiCath monitoring system permits near zero blood loss for ABG assessment and greatly reduces the time needed to make ventilator management decisions.