The effects of a pressure relief mattress on postnatal head molding in very low birth weight infants.

: Very low birth weight (VLBW) infants often develop postnatal head molding (PHM)--an elongation of the skull--when a standard, firm mattress is used. This study was undertaken to determine if a pressure relief mattress (PRM) might reduce the severity of PHM. One hundred twenty-eight infants (birth weight range 567-1,490 gm, mean 1,084; gestational age range 24-36 weeks, mean 28.5) with no congenital or acquired anomalies affecting head growth were randomly assigned to a control group (standard, firm mattress) or a study group (PRM). Study infants were placed on the PRM within 72 hours of birth. Occipitofrontal circumference (OFC) and anterior-posterior (AP) and biparietal (BP) diameters were measured at day four, seven, and then at one week intervals of life until the infant reached 2,000 gm or was discharged. An electronic digital caliper with an accuracy of 0.025 mm was used to obtain the AP and BP measurements. T-tests revealed no significant differences in head shape between the two groups. In conclusion, the pressure relief mattress did not reduce PHM in VLBW infants.