942 CONGENITAL CARDIOGENIC SHOCK AS A RESULT OF PERINATAL ASPHYXIA

Effective treatment of cardiogenic shock (CS) as a result of severe perinatal asphyxia (PA) in preterm infants is dependent on its early recognition and differentiation from RDS. Four preterm infants weighing 1240-2300 g., G.A. 32-34 wks., who had abnormal fetal heart rate pattern and acidosis, developed CS shortly after birth. All were severely depressed at birth and required prolonged resuscitation. ECG, heart rate (HR) and variability, aortic pressure (ABP), right atrial pressure (RAP), core and toe-skin temperatures, arterial blood gases, glucose, calcium, and lactic acid (LA) were measured in all. Respiratory failure requiring assisted ventilation, tachycardia, decreased HR variability, hypotension, elevated RAP, decreased toe and core temperatures, markedly elevated LA and alveolo-arterial oxygen gradients were noted in each shortly after birth. Initial chest radiographs revealed cardiomegaly and diffuse alveolar and interstitial edema. One infant improved spontaneously while 3 infants required iso-proterenol infusion in the first 6 hours. One infant died of persistent CS while 2 infants responded dramatically showing reversal of abnormal findings listed above, enabling discontinuation of assisted ventilation within 24 hours. This data suggests that severe PA may result in myocardial dysfunction leading to CS in preterm infants. Although presentation of CS resembles HMD, it can be differentiated by chest X-rays, elevated RAP and markedly elevated LA. Early use of isoproterenol can reverse severe heart failure leading to rapid recovery.