Comparison between oscillometric and invasive blood pressure measurements in critically ill premature infants

Blood pressure (BP) measurement techniques in neonates generally involve noninvasive measurements with a cuff (oscillometric) or invasive measurements through an arterial catheter. The aim of this study was to determine the reliability of the noninvasive oscillometric method in critically ill preterm infants when results were compared with the invasive technique.

Twenty-seven premature infants with a mean birth weight of 1138 ± 552 g were enrolled in the prospective study. Invasive and noninvasive mean arterial pressure (MAP) levels were recorded simultaneously at each measurement in all patients. Low or lower range mean invasive MAP values (MAP ≤30) were evaluated separately as we aimed to assess the value of noninvasive measurements in hypotensive sick premature infants.

Totally, 431 paired BP measurements were taken during the first week of life. There was no statistically significant difference between invasive and noninvasive readings. However, noninvasive measurements were found significantly higher compared with invasive measurements in the presence of hypotension (p < 0.05).

This study showed good agreement between oscillometric and invasive readings in critically ill premature infants, and further, comparable mean MAP values were found with the two methods. However, the accuracy of the oscillometric BP measurement technique fails in preterm infants with BP within the lower limits.