Anaesthesia for posterior fossa surgery

Surgery on the posterior fossa is technically challenging and requires surgical skill and judgement. The anaesthetist through an understanding of the surgeon's problems, the provision of ideal operating conditions, the meticulous monitoring for changes in vital signs and good communication with the surgeon can make a crucial contribution to successful outcome for the patient. The positioning of patients poses particular problems. The prone and lateral positions, together with the supine for transoral surgery, can provide for appropriate access to all parts of the posterior fossa. Traditionally it has been argued that the sitting position offers specific advantages although it creates additional problems for the anaesthetist. In recent years the potential risks of sitting patients up have been extensively investigated and concern has focused in particular on the danger of paradoxical air embolism. Although its safety in recognized centres has been demonstrated, it is clear that this position is now falling out of favour.