This experience with strokes induced by hyperventilation during repose in patients with SS is presented to caution against its use in patients with SS. We have discontinued hyperventilation during EEC in all of our patients with SS. Cheatham and Brackett12 and Richards and Nulsen13 state that the risks of angiography in patients with SS are significant. However, Stockman et al. have recently demonstrated that with repeated exchange transfusion preparation, angiography can be carried out without incident. Even so, we did not feel these patients were surgical candidates; therefore, angiography was not performed.
If further experience with hypertransfusion should prove effective in producing clinical and functional neurological improvement, angiography would be a useful tool in following the course of the vascular disease. Certainly, the angiographic reversal of the vascular disease would suggest that hypertransfusion may be helpful in patients with SS who have had transient cerebral episodes.