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

Abstract

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

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

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

Patients: 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].

Measurements: 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.

Results: 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.

Conclusions: 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.