To investigate the changes in systemic and cerebral haemodynamics between supine and prone sleep in healthy term infants during the early postnatal period.Design/methods
Healthy term infants without congenital anomalies, patent ductus arteriosus and/or small for gestational age status were enrolled. Infants were placed in supine (SP1), prone (PP) and back in supine (SP2) position for 15 min each while asleep. Cardiac output (CO) and stroke volume (SV) were assessed by electrical velocimetry (EV) and echocardiography (echo), and cerebral regional oxygen saturation (CrSO2) in the frontal lobes was monitored by near-infrared spectroscopy. Heart rate (HR) and SpO2 were continuously monitored by conventional monitoring.Results
In 34 healthy term infants (mean age 3.7±1.2 days; 16 females), 66 sets of serial CO measurements (34 EV and 32 echo) in three sleep positions were obtained. Mean COEV and COecho were 182±57 (SP1), 170±50 (PP) and 177±54 (SP2), and 193±48 (SP1), 174±40 (PP) and 192±50 (SP2) mL/kg/min, respectively. Mean SVEV and SVecho were 1.46±0.47 (SP1), 1.36±0.38 (PP) and 1.37±0.39 (SP2), and 1.54±40 (SP1), 1.38±0.38 (PP) and 1.51±0.41 (SP2) mL/kg, respectively. Repeated measures analysis of variance revealed a decrease in CO and SV during prone positions by both EV and echo, while HR, SpO2 and CrSO2 did not change. Thirty-eight per cent of the CO measurements decreased≥10% during prone positioning.Conclusions
In healthy term infants, CO decreases in prone position due to a decrease in SV and not HR. CO recovers when placed back in supine. However, frontal lobe CrSO2 does not change in the different positions.