Persistently low cardiac output predicts high mortality in newborns with cardiogenic shock

Cardiogenic shock is an acute "unstable" state of circulatory dysfunction.

To evaluate the haemodynamic aspects of 45 newborn infants affected by cardiogenic shock, in relation to etiologies and the mortality rate.

Retrospective, correlation study of etiologies, mortality rate and haemodynamic measurements by Doppler ultrasound parameters.

45 newborn infants with cardiogenic shock, Gestational Age (GA) 37 (34-41), Birth Weight (BW) 2750 (1600-3600) g and and a control group of 20 neonates [GA 38 (34-40) wks, BW 2960 (1750-3800) g].

Left ventricular Cardiac Output (CO) was measured by a duplex scanner with pulsed Doppler and color flow mapping echocardiography in the first 48 hours of life.

In healthy newborns CO was 240 mL/min/kg (210-280), in newborns with cardiogenic shock CO was 170 mL/min/kg (f130-200), p < 0.01. The Stroke Volume was 1.80 mL/kg (1.70-1.90) in the control group and 1.20 (1.15-1.80) in the shocked group (p < 0.05); Heart Rate was 146 beats/min (130-160) and 160 beats/mm (140-194), (p < 0.01) respectively. Twenty-nine infants with cardiogenic shock had CO < or = 150 mL/min/kg and 5 of them (17.2%) died; 16 neonates had CO > 150 mL/min/kg and only one (6.2%) died (p < .01). Twenty-six of 36 newborns with perinatal asphyxia had CO < or = mL/min/kg and 5 of them died, while only one of 10 infants with CO > 150 mL/min/kg died.

Our results show that persistently low CO (< or = mL/min/kg) during the first 48 hours life, in newborns with cardiogenic shock due to perinatal asphyxia is associated with a significantly higher mortality.