Although acute chest syndrome (ACS) is a common complication of sickle cell anemia, there are few date on how it is managed. We reviewed the medical records of 20 children with a total of 43 episodes of ACS at the University of Rochester from 1980-1995 and examined the outcome of these children based on whether they were simply observed, received a straight transfusion or a partial volume exchange transfusion. In 18 episodes of ACS, initial therapy was observation without blood transfusion. The mean temperature (T) of these children was 38.8° C, respiratory rate (RR) 32, room air O2 saturation (O2 sat) 93%, Hct 23. In 7 of these cases (39%) the children were subsequently transfused due to deterioration of their respiratory status. All 18 patients recovered; their mean hospital stay was 3.8 days. Initial management of another 7 cases of ACS included simple transfusion. The mean T of these children was 38.4° C, RR 42, O2 sat 89%, Hct 21. In one case (14%) the child required an additional transfusion due to no clinical improvement. All children recovered; their mean hospital stay was 5.7 days. Partial volume exchange transfusion was used in the initial management of another 18 episodes of ACS. The mean T of these children was 38.8° C, RR 45, O2 sat 88%, Hct 20. One child died, the remaining children recovered; their mean hospital stay was 5.1 days. In conclusion, there is a subset of children with ACS who can be safely observed or managed with straight transfusion only.