The use of recombinant tissue-type plasminogen activator in a newborn with an intracardiac thrombus developed during extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation (ECMO) support is often used to support infants and children with hemodynamic or respiratory failure. One of the major obstacles of safely treating a child with ECMO is balancing the risk of hemorrhage with the potential for thrombus development. Managing thrombosis in the setting of ECMO is challenging and has no defined algorithm. The use of recombinant tissue-type plasminogen activator (tPA) for thrombolysis has been previously described in cases where thrombi have developed despite adequate anticoagulation. In such situations, the risk of hemorrhage must be carefully balanced with the benefit of dissolving the clot and reestablishing flow. We present a case of an infant who required ECMO because of severe primary pulmonary hypertension and subsequently developed a right atrial thrombus adjacent to the ECMO cannula. The patient was treated with tPA with immediate improvement but had fatal intracranial hemorrhage almost 3 days after the tPA was administered. In this report, we review the current literature on tPA use during ECMO support and suggest a rational approach.

Pulmonary hypoplasia with an unusual prenatal history.

We describe a monochorionic, diamniotic twin with renal agenesis who received amniotic fluid from his normal co-twin by spontaneous rupture of the amniotic septum between them. By 16 weeks of gestation the presence of severe oligohydramnios in one twin had resulted in renal agenesis, but not in the other twin, who did not have oligohydramnios. By 20 weeks of gestation, the two amniotic fluid volumes had become the same in both twins. At 33 weeks, the twins were delivered by cesarean section. Despite intensive respiratory care, the twin with renal agenesis died from severe pneumomediastinum on day 3. At autopsy, pulmonary hypoplasia was demonstrated in that twin. This experiment of nature demonstrates that oligohydramnios during the early canalicular stage of pulmonary development (gestational age, 16-20 weeks) may be pathogenically important in pulmonary hypoplasia.

Primary congenital pulmonary hypoplasia--genetic component to aetiology.

Primary congenital pulmonary hypoplasia, defined as congenital pulmonary hypoplasia occurring in the absence of other congenital anomalies, is an exceedingly rare condition of unknown aetiology. We report on two cases that presented as severe progressive respiratory failure immediately after birth in siblings of a consanguinous marriage, and we postulate that a genetic aetiology may be responsible for the arrest of lung maturation in utero. The possibility of a genetic component to the aetiology has not been previously documented in the literature.

High-frequency oscillatory ventilation (HFOV) in the treatment of neonatal respiratory disturbances: case reports of two infants.

The technique of high-frequency oscillatory ventilation (HFOV) was successfully used in a preterm infant with severe hyaline membrane disease and in a term neonate presenting with intrauterine pneumonia and associated severe pneumomediastinum. None of the infants could adequately be ventilated by conventional ventilation; both of them deteriorated owing to severe hypoxaemia and hypercapnia. In the preterm infant with HMD a rapid and progressive improvement of oxygenation had been observed immediately after the beginning of HFOV, and he was successfully weaned off the ventilator after 71 hours on HFOV. His recovery was uncomplicated and definitive. In the term neonate presenting with IUP and associated severe PM, an improvement in oxygenation was detected, whereas the retention of paCO2 remained unaltered. On leaving the MAP unchanged but doubling the flow rate, paCO2 and arterial pH also normalised. No sign of PM was seen on the X-ray picture 17.5 hours after the start of HFOV. This patient was weaned off the ventilator after 29 hours on HFOV and his recovery was also uncomplicated. It is believed that recovery of the PM was secondary to the low MAP and to the higher arterial pO2 levels, and that HFOV may also have a direct role in the treatment of preexisting air leaks and perhaps also in their prevention. In our patients HFOV resulted in a definitive recovery, while no improvement had occurred on using conventional ventilation. To determine the exact mechanism of action, the clear cut fields of indications and the possible side effects of HFOV, further investigations are needed.