AUTOPSY IN A NEONATAL INTENSIVE-CARE UNIT - UTILIZATION PATTERNS AND ASSOCIATIONS OF CLINICOPATHOLOGICAL DISCORDANCES

Objectives: (1) To develop methods to describe autopsy utilization pat terns in a neonatal intensive care unit. (2) To identify classes of pa tients likely to have clinicopathologic concordance or discordance. Me thods: Five hundred forty-five consecutive neonatal intensive care uni t deaths (338 autopsied, rate 62%) in a regional tertiary/quaternary c are neonatal intensive care unit for referred infants (65,000 annual b irths) were classified in six clinical diagnostic groups (anomalies, c ardiac anomalies, hypoxic ischemic encephalopathy, prematurity and its complications, infections, and other) and rated in three levels of ce rtainty of clinical diagnosis as ''gold standard'' certainty almost co mplete certainty, and less certain than the latter. Clinicopathologic discordances were rated in three classes using clinical, pathologic, a nd multidisciplinary mortality conference records. The proportions of autopsied cases, cases with major discordances, and cases with no disc ordances were compared and analyzed in relation to diagnostic group an d level of certainty. Results: Performance of autopsy was associated w ith clinical diagnostic uncertainty (p = 0.008). Major discordances wi th implications for outcome (Class I) were found in 3%, and without im plications for outcome (Class II) in 15% of cases; 42% of cases had no discordances. Major discordance rate varied inversely with the degree of diagnostic certainty (p = 0.000) and varied among clinical groups. Conclusions: (1) Autopsy was used most for cases with potential for h igh yields. (2) Clinicopathologic discordances were more frequent and important in certain clinical diagnostic groups (prematurity, other) a nd with high levels of diagnostic uncertainty. When the diagnostic ''g old standard'' is available during life, autopsy will provide little i nformation.