CAPILLARY REFILLING TIME AND HEMODYNAMICS IN NEONATES - A DOPPLER-ECHOCARDIOGRAPHIC EVALUATION

Objective: To evaluate the correlation of the capillary refilling time measured in neonates with the hemodynamic parameters obtained by Dopp ler echocardiography. Design: Prospective study. Setting: Neonatal int ensive care unit (ICU) in a university hospital. Patients: Neonates wi thout congenital cardiac disease admitted to the neonatal ICU (n = 100 ), interventions: None. Measurements and Main Results: The clinical pa rameters obtained were: heart rate; blood pressure; mean airway pressu re; cutaneous temperature; and capillary refilling time. The echocardi ographic data included the measurement of aortic diameter, left atrial diameter, and shortening fraction. Pulsed-Doppler echocardiography wa s used to measure flow velocity values in the ascending aorta, in the pulmonary artery trunk, and in the patent ductus arteriosus. Cardiac i ndex was calculated secondarily from the volumetric equation, includin g measured flow velocity in the ascending aorta, aortic diameter, and body weight. Shunt severity at this level was measured by analysis of the descending aortic flow. Thereafter, three groups were defined for analysis: group 1 with obliterated ductus arteriosus; group 2 with pat ent ductus arteriosus without a retrograde flow in the subdiaphragmati c aorta; and group 3 with patent ductus arteriosus and a retrograde fl ow in the subdiaphragmatic aorta. There was no correlation between the capillary refilling time and the following parameters: shortening fra ction; mean airway pressure; body weight; left atrial diameter/aortic diameter ratio; blood pressure; and heart rate. In group 1,the capilla ry refilling time was significantly linked to cardiac index (r(2) = .5 4, p < .001). A lower correlation coefficient between capillary refill ing time and cardiac index was found in groups 2 (r(2) = .31, p < .001 ) and 3 (r(2) = .41, p < .001). Conclusion: The capillary refilling ti me was significantly linked to cardiac index in neonates.