Oops, my mistake, I thought you were talking about labor epidurals, even though your post clearly says post c-section pain. I always (barring allergy) give epidural or intrathecal morphine for that.
I'm actually doing my MOCA-required practice assessment/improvement bit now, looking at changing my spinal narcotic dose for c-cection pain.
That's exactly what I settled on as a CA2 and have done ever since - 0.75% hyperbaric bupivacaine (usually 1.6 mL) + 15 mcg fentanyl + 200 mcg morphine for scheduled c-sections. Then periopdoc put a thought in my head in
this recent Duramorph/Bupiv Spinals thread about dropping the fentanyl and using just 100 mcg of morphine ... There is published data supporting the notion that 100 mcg is just as good as 200 mcg for pain control, with fewer side effects.
So I decided to try it. I dug up charts for my last 20 scheduled sections and mined the postop pain scores, postop PRN pain nausea and pruritis meds given. Since then I've done 11 out of 20 planned sections with just the 100 mcg morphine dose. (Our OB census is very dry right now so god only knows how much longer it'll take me to do another 9.)
I'm unimpressed with 100 mcg morphine instead of 200 mcg + 15 fentanyl so far. Comparing the two groups, there 100 mcg group has had more pain for the entirety of the first 24 hours postop (edging toward statistical significance in the 8-12 and 12-16 hour postop time periods), more pain meds requested, and similar rates of nausea and pruritis. Caveats - small sample size, not prospective/randomized/blinded/etc, but it looks like I'll go back to the 200 + 15 dosing when I'm done with this project.