Evaluation of post extracorporeal membrane oxygenation follow-up testing

The purpose of this study was to evaluate all post extracorporeal membrane oxygenation (ECMO) tests for their ability to detect any change in the incidence of unanticipated medical problems, and their charge to the patient. The current post ECMO protocol consists of the following tests: brain stem auditory evoked response, head computed tomography, cerebral blood flow, head ultrasonography, electroencephalography, eye examination for retinopathy of prematurity, and pneumocardiography. A retrospective review was conducted for all surviving neonatal ECMO patients treated from January, 1985, to December, 1994. The results of each test were classified as either normal, having a minor abnormality, or having a major abnormality. Statistical analyses were performed on each test comparing the incidence of minor and major abnormalities to all neonates in the neonatal intensive care nursery. Two hundred ninety-six infants survived their course on ECMO, and composed the study population. There were no significant differences between the incidence of abnormal results compared with the expected values for the following tests: cerebral blood flow (p=0.13), the eye examination (p=0.54), and pneumocardiography (p=0.22). The analyses for the brain stem auditory response, head computed tomography, head ultrasonography, and electroencephalography showed higher than expected incidences of abnormal results (p < 0.01). The data also were evaluated for major abnormalities on computed tomography and head ultrasonography. Of 161 infants who had both tests performed, 11 (6.8%) had normal head ultrasonography results, yet had a major abnormality noted on computed tomography (p < 0.01). This study is the first to review the current post ECMO protocol comprehensively, and the results suggest excluding the cerebral blood flow, eye, and pneumocardiography tests. This would result in a significant savings of $1,400 without compromising patient care. In addition, comparisons of neuroradiographic studies indicate that computed tomography of the head is sensitive enough to detect all central nervous system abnormalities that were found by ultrasonography. Excluding the post ECMO head ultrasonography, an additional savings of $300 would occur. These recommended changes reflect the current post ECMO protocol at Kosair Children's Hospital.