A few other factors may be important to make that decision. Degree of illness, underlying pathology, Gestational age, BW and postnatal age of the baby. Of course the Threshold for ET will change based on these factors. For example we recently had a full term baby with liver failure due to GALD in which case ET will be needed.
However for an otherwise healthy baby with those numbers ET may not be needed. We had a similar vcase of a baby with inspissated bile syndrome. The direct Bili was elevated for over a month!