Survival of Infants With Persistent Pulmonary Hypertension Without Extracorporeal Membrane Oxygenation

Abstract

A retrospective evaluation was performed of the survival after conservative therapy of infants with persistent pulmonary hypertension who met the published criteria of Bartlett et al (Pediatrics. 1985;76:479-487) or Short et al (Clinics in Perinatology. 1987;14:737-748) for extracorporeal membrane oxygenation (ECMO) therapy. An 80% to 90% mortality rate can be predicted with these criteria, which are based on historical data, if ECMO is not used. The records of infants with the diagnosis of persistent pulmonary hypertension, weighing > 2 kg at birth and who were treated during two time periods, January 1980 to December 1981 [23 patients] and January 1986 to December 1988 [17 patients], were reviewed. During the earlier period, hyperventilation was the mainstay of our therapy, whereas during the later period, a more conservative approach (avoidance of hyperventilation) was adopted. In 1980 to 1981, 1 of the 6 patients (17%) who were eligible for ECMO by criteria of Bartlett et al survived, which is consistent with the published data. However, in 1986 to 1988, 9 of 10 ECMO-eligible patients (90%) survived (P < .02). The corresponding survival figures using the alveolar-arterial oxygen difference criteria of Short et al were 0 of 5 survivors (0%) in 1980 to 1981 and 8 of 9 (89%) in 1986 to 1988 (P < .006). These data indicate that approximately 90% of patients who are candidates for ECMO now survive in our institution without the use of that therapy. Because this was a retrospective analysis, it is not known whether the improved survival is related primarily to the change in ventilator therapy. Because the prognosis of persistent pulmonary hypertension is changing with time, indications for alternative modes of therapy, such as ECMO, and assessment of the effectiveness of such therapy should not be based on historical data. A randomized clinical trial in which conservative ventilation is compared to hyperventilation and to ECMO in the management of persistent pulmonary hypertension should be undertaken before further expenditures on ECMO centers are made. The focus of such a study should be on morbidity as well as mortality.