Low cerebral blood flow velocity and head circumference in infants with severe hypoxic ischemic encephalopathy and poor outcome.

AIMS: To evaluate long-term changes in cerebral blood flow velocity (CBFV) and head circumference in asphyxiated infants. METHODS: CBFV was measured in 83 asphyxiated and 115 healthy term infants in anterior and middle cerebral, basilar and internal carotid artery (ICA) up to the age of 60-149 days. The psychomotor development and head circumference was followed for 18 months. RESULTS. Mean CBFV was increased (p < 0.05) during the first days after asphyxia in infants with severe hypoxic-ischemic encephalopathy (HIE) (n = 25) compared to control group or infants with mild to moderate HIE (n = 58) with maximum values found at the age of 36-71.9 h: in ICA (mean [95% CI]) 31.2 (25.5-36.6) cm/s in severe HIE infants compared to 13.0 (12.2-13.9) cm/s in controls. Decreased (p < 0.0001) mean CBFV developed in severe HIE infants by the age of 21-59 days: in ICA 14.1 (11.5-16.8) cm/s compared to 22.9 (21.4-24.4) cm/s in controls. Infants with severe HIE had similar mean height but lower head circumferences compared to controls (p < 0.05) at the age of 21-59 days. CONCLUSION: The high mean CBFV found in infants with severe HIE during the first days after asphyxia is temporary and low CBFV and head circumference develops by the age of 21-59 days.

Changes in cerebral and visceral blood flow velocities in asphyxiated term neonates with hypoxic-ischemic encephalopathy.

OBJECTIVE: The purpose of this study was to evaluate changes in the Doppler blood flow velocity (BFV) in the cerebral and visceral arteries in asphyxiated term neonates. METHODS: The BFV was measured in 47 asphyxiated and 37 healthy term neonates in the anterior cerebral artery, middle cerebral artery, basilar artery, internal carotid artery, celiac artery (CA), superior mesenteric artery (SMA), and renal artery (RA) up to the age of 60 to 149 days. RESULTS: At the age of 12 to 120 hours after asphyxia, the mean BFV had increased, and the resistive index (RI) had decreased (P < .05) in all cerebral arteries in neonates with severe hypoxic-ischemic encephalopathy (HIE) compared with the control group. In neonates with severe HIE, the mean BFV in the RA had significantly decreased at the age of 3 to 240 hours, and the RI had increased at the age of 24 to 240 hours, normalizing by the age of 21 to 59 days compared with the control group (P < .05). In the SMA, a decreased mean BFV was found in neonates with severe HIE compared with those with mild to moderate HIE only at the age of 24 to 36 hours. In neonates with mild to moderate HIE, the mean BFV had increased in the SMA and CA compared with the control group at the age of 2 to 11.9 hours. CONCLUSIONS: A severe alteration of the cerebral and visceral BFV takes place during the first days after asphyxia in neonates with different severities of HIE.

Developmental changes in cerebral and visceral blood flow velocity in healthy neonates and infants.

OBJECTIVE: The purpose of this study was to evaluate the changes in Doppler blood flow velocity (BFV) in cerebral and visceral arteries during infancy. METHODS: The BFV was measured in 37 healthy term neonates in the anterior cerebral artery (ACA), middle cerebral artery (MCA), basilar artery, internal carotid artery (ICA), celiac artery (CA), superior mesenteric artery (SMA), and renal artery (RA). RESULTS: The mean BFV increased and the resistive index decreased (P < .05) in all cerebral arteries, SMA, and CA by the age of 12 to 23.9 hours and in the RA by the age of 24 to 35.9 hours compared with 2 to 11.9 hours. A further significant increase (P < .05) of the mean BFV occurred in all arteries except the ICA and CA by the age of 72 to 120 hours compared with 12 to 23.9 hours. By the age of 21 to 59 days, the mean BVF doubled in all investigated arteries compared with 2 to 11.9 hours, with a further significant increase (P < .05) by the age of 150 to 240 days in cerebral and renal arteries. There was no correlation between the mean blood pressure (BP) and mean BFV in the ACA and MCA. However, there was a positive correlation (r > or = 0.5; P < .05) between the BP and BFV in the RA and SMA at the age of 12 to 23.9 hours. CONCLUSIONS: A significant increase in the cerebral and visceral BFV occurs normally throughout infancy, with the visceral BFV affected by BP changes during the first day of life.