Given your limited presentation, LMA nearly always at the top of my list in this patient with this problem. That is a small hernia sac and should be about a 30 min case.
I have done a handful of umbilicals/inguinals in cripples with copious old school surgeon placed local and sh*tty MAC.
a lot of the approach is going to depend on how reasonable the surgeon and patient are.
there is nothing in your presentation that suggests difficult airway other than she is small, brittle, and old. If she isn’t kyphotic with a frozen neck and a reassuring airway exam then throw a tube in.
I’ve never spinaled an umbilical hernia, not that would never but plenty of other options for a small hernia so her scoliosis doesn’t mean much to me assuming she can lie flat and bend her neck.
Why was your attending so against a LMA? He must keyed in on something. so what am I missing? clearly you had some fireworks.