The lounging position for posterior fossa surgery: anesthesiological considerations regarding air embolism.

The sitting position for operations in the posterior fossa remains controversial in both adults and children, primarily because of the risk of air embolism. The reports on the incidence of this complication are varied. We retrospectively reviewed the data on 704 patients (age range 1-82 years) operated on in a lounging position for varied posterior fossa pathology from January 1984 up to December 1989. As diagnostic monitoring, we uniformly employed a Doppler ultrasound device, an atrial catheter, and capnometry. In 37 adults (5.5%) and 9 children (9/34) air embolism was diagnosed, without either morbidity or mortality. A lounging position, together with adequate infusion therapy and ventilation with PEEP, considerably reduces the risk of air embolism.