Purpose: To ascertain whether the methods of prone positioning we use have any influence on the incidence of perioperative critical incidents and development of postoperative liver dysfunction in our scoliosis patients.

Methods: A retrospective review of 72 patients undergoing posterior correction and fusion for scoliosis from August 2006 to November 2007. Details were recorded from anaesthetic charts, operation notes, blood results and cell salvage data.

Results: Patients ranged in age from 2 to 24 years. The methods of prone positioning were Transverse Bolsters (23), Allen Frame 4-point support (25), Lateral Bolsters (11) and the Knight Table (13). Perioperative haemodynamic instability was noted in 8% of patients on the Allen Frame, 43% on transverse bolsters, 15% on the Knight Table and 55% on lateral bolsters. Two cardiac arrests, one fatal and one with good recovery, both occurred on transverse bolsters. Of 22 other complications attributable to mechanical effects of prone positioning, 16 occurred on transverse bolsters, 4 on the Allen Frame, 1 on lateral bolsters and 1 on the Knight Table. 34% of patients had liver dysfunction postoperatively. None had been positioned on the Knight Table or lateral bolsters. There was no significant difference between the incidence of liver dysfunction associated with the Allen Frame or transverse bolsters.

Conclusion: Transverse bolsters are associated with a high number of critical incidents and should be avoided if possible.

Ethics approval – not required

Interest Statement - none