I had many many surgeries. Around 20 in the 6 months after my first episode. The surgeries were a consequence of my compartment syndrome, and they were quite big (1-3 hrs), with general anesthesia. There were always problems with wound infections.
I did not get Ivig in these days. In fact, the doctors that treated me for a long time in hospital could have known that I have SCLS, but did not react adequately (what caused many troubles on the long run). No SCLS related problems.
Since 2 1/2 years I get Ivig. Since then I had two other, smaller surgeries: arthrodesis at the toes of my feet, left and right. No problems related to SCLS.
If the surgery is medically indicated, I would do it and take extra care. Of course all your doctors should be informed about the signs of an episode and what to do then.