Alice French Andrews

Venovenous perfusion in ECMO for newborn respiratory insufficiency. A clinical comparison with venoarterial perfusion

Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) has been successful in the treatment of newborns less than 1 week of age and greater than 2000 gm birthweight with respiratory failure resistant to current medical and surgical management. While VA ECMO supports the heart as well as the lungs, it has the disadvantage of requiring carotid artery ligation and the possibility of perfusing air bubbles or particles into the arterial tree. We have treated 11 newborns with respiratory failure with venovenous (VV) ECMO returning the oxygenated blood to a cannula in the distal iliac vein. We compared these patients with 16 patients treated during the same period of time with VA ECMO. Three of the 11 VV patients required conversion to VA ECMO because of inadequate oxygenation and unstable hemodynamic situations. Ten of the 11 VV patients survived. Eleven of the 16 VA patients survived. The better survival in these patients treated with VV ECMO is attributed to their more favorable initial condition compared to patients treated with VA ECMO. The disadvantages of VV ECMO include a longer operative time to place the cannulas, groin wound problems, and persistent leg swelling along with the necessity to convert some patients to VA ECMO. Although this experience demonstrates that newborns with severe respiratory failure can be supported with VV ECMO, the complications and lack of practical advantages over VA lead us to recommend VA ECMO for routine clinical use at present.

Venovenous extracorporeal membrane oxygenation in neonates with respiratory failure

Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) has been successful in support of neonates with respiratory failure but requires right common carotid artery ligation. While no short-term neurologic complications have resulted from neonatal carotid ligation, late complications may occur. For both VA ECMO and venovenous (VV) ECMO, blood is drained from the right atrium via a right internal jugular cannula, oxygenated by a membrane lung, and returned to the patient. VV ECMO spares the carotid by perfusing the oxygenated blood into a vein. VV ECMO gave total respiratory support to three neonates with respiratory failure and each infant survived. In comparison with three similar VA ECMO patients, the VV patients required higher ECMO circuit flow rates and had lower systemic arterial Po2s. Length of time on ECMO, length of hospital stay, and neurologic outcome were similar in the VV and VA patients. Differences among the patients were related to their primary disease rather than to the mode of ECMO support. The VV patients had cannulation of the femoral vein for perfusion of oxygenated blood. Late complications may occur from femoral vein ligation as well as from carotid ligation so long-term follow-up is needed to assess these two ECMO techniques.

Complete resolution of life-threatening hemangioma by embolization and corticosteroids.

A case is presented in which congestive heart failure and thrombocytopenia were complications of an inoperable hemangioma in a neonate. Selective embolization of the hemangioma in the patient achieved significant diminution in the congestive failure and tided this infant through the first few days of life while awaiting positive effects from the steroids and external compression. The combined treatment modalities of selective embolization, external compression, and short course of low-dose systemic steroids resulted in a rapid and complete resolution of this life-threatening problem.

Extracorporeal membrane oxygenation for newborn respiratory failure: Forty-five cases

Abstracts Respiratory failure is a common cause of death in newborn infants. The standard treatment for this condition (oxygen and airway pressure) can cause lung damage and is itself a major contributor to morbidity and death among the newborn. Extracorporeal membrane oxygenation involves the use of a modified heart-lung machine to support gas exchange for a period of days or weeks until the lung has recovered. In the past 8 years, the present authors have used the method in the treatment of 45 newborn infants with respiratory failure. This report describes their total experience and updates previous publications on the subject. The patients were selected and referred by neonatologists, who pronounced them unresponsive to maximum therapy. They were said to have less than a 10 per cent chance to survive before entering the study. In all cases, venoarterial cardiopulmonary bypass was established by cannulating the right atrium via the right jugular vein and the aortic arch via the right common carotid artery. The extracorporeal circuit included polyvinylchloride tubing, a membrane lung, a pump with a 10-ml venous reservoir bladder, and a heat exchange to maintain temperature (Fig. 1). The priming volume of the circuit was approximately 450 ml. During priming, care was taken to ever, the patients were returned to maximal ventilatory support without extracorporeal membrane oxygenation. Four such patients suffered cardiac arrest, brain damage, or intracranial hemorrhage in the process. Of 25 survivors, 20 are apparently normal, healthy children with normal growth and development. Two patients had mild spasticity of the lower extremities, which has since improved almost to the normal state. One child developed hydrocephalus in the newborn period and has a functioning ventriculoarterial shunt. One child has a large right encephalic cyst with severe neurological impairment at 2 years of age. Another child, treated for right-sided diaphragmatic hernia, regained sufficient pulmonary function to permit discontinuation of extracorporeal membrane oxygenation. This child was discharged briefly from the hospital but died of chronic respiratory failure at the age of 1 year and 6 months.

BILIRUBIN ALBUMIN BINDING (BAB) ASSAY IN NEWBORN INFANTS BEFORE, DURING AND AFTER EXTRACORPOREAL MEMBRANE OXYGENATION (ECMO)

Red blood cell destruction during ECMO may increase the risk for hyperbilirubinemia and bilirubin neurotoxicity. For this reason we performed bilirubin binding studies on 12 newborn infants (mean ± SD, gestational age 37.6±3.6 wks, birth wt 2889±706 gms) managed with ECMO for respiratory failure. The mean duration of ECMO was 91.1±37.2 hrs. Bilirubin binding studies including reserve bilirubin binding capacity (RBBC), and saturation index (SI) were performed using a bilirubin fluorometer.No significant changes pre, on, or post ECMO were noted on the hemoglobin and fibrinogen levels. The bilirubin levels were not significantly different pre and on ECMO and were lower post ECMO. As shown in the table, there were significant changes pre, on, and post ECMO plasma hemoglobin values. Significant changes between pre and on ECMO values only were noted on the infants platelet, fibrin split products and SGOT levels. Thus, the hemolysis that occurs during ECMO does not adversely effect the RBBC and SI from any alterations in the bilirubin load or in the BAB sites. ECMO would not predispose an infant to bilirubin neurotoxicity because of the normal BAB values pre, on, and post ECMO.