Source: Campbell et al. Anesth Analg 2001; 93: 1006-11

Reviewer:  R. Prasad, MD

Summary:

• Addition of 0.1mg MSO4 to 60mg hyperbaric lidocaine SAB
• 24 hr follow-up and evaluation:
• Decreased pain VAS, PCA MSO4 use
• Increased satisfaction (96.6/100 vs. 39.6/100)
• Similar adverse effect profile
• Delayed ambulation: better pain control so able to rest? motor strength not tested, simply recorded time of first ambulation.

• Their study protocol req'd. all women to remain in hosp 24 hrs ... improved analgesia may allow earlier discharge (although a few hours may not be very significant)
• Mean pain VAS in NS group not terribly high, but the standard deviation was large - i.e., many pts did have significant (VAS>40) pain. So, this may be a useful addition to spinals for postpartum BTLs
• We often use epidurals already in place ... wonder if adverse effect profile any different with epidural MSO4?
• They had no TNS in either group despite using hyperbaric lidocaine. Sample size was not large, but this is a pretty low risk group, anyway.

• 66 ASA I-II for BTL within 72h vaginal delivery, BTL 7am-4pm
• Naproxen 500mg 60min preop
• Randomized to addition of 0.2ml saline or duramorph (0.1mg) to 60mg 5% lido for SAB (blinded)
• Postop pain by PCA (IV MSO4) only

• 6 excluded for protocol violations
• Demographics, gestational age, parity, preop pain VAS, birth weights all similar
• Intraop hypotnesion, nausea, sensory level also similar
• Postop VAS  pain higher in NS group at 4, 8, 12, and 24hrs
• Crampy abd pain: ~25mm vs. ~2mm
• Incisional pain at rest: ~10mm vs. ~2mm
• Incisional pain with mbmt: 20-30mm vs. ~4mm
• Time to first PCA: 238min NS vs. 720min MS
• Cumulative MSO4: 39.6mg NS vs. 1.1mg MS
• Adverse effects (nausea, pruritus, urinary retention, resp depression, PDPH, TRI): no significant difference (although incidence of pruritus 77% MS vs. 57% NS, p>0.05, and only 3% NS vs. 10% MS patients reqd tx)