Acute Pain Burden and Opioid Dose Requirements after Cesarean Delivery in Parturients with Preexisting Chronic Back Pain and Migraine.

INTRODUCTION: Preexisting chronic pain has been reported to be a consistent risk factor for severe acute postoperative pain. However, each specific chronic pain condition has unique pathophysiology, and it is possible that the effect of each condition on postoperative pain is different. METHODS: This is a retrospective cohort study of pregnant women with preexisting chronic pain conditions (i.e., migraine, chronic back pain, and the combination of migraine + chronic back pain), who underwent cesarean delivery. The effects of the three chronic pain conditions on time-weighted average (TWA) pain score (primary outcome) and opioid dose requirements in morphine milligram equivalents (MME) during postoperative 48 hours were compared. RESULTS: The TWA pain score was similar in preexisting migraine and chronic back pain. Chronic back pain was associated with significantly greater opioid dose requirements than migraine (12.92 MME, 95% CI: 0.41 to 25.43, P=0.041). Preoperative opioid use (P < 0.001) was associated with a greater TWA pain score. Preoperative opioid use (P < 0.001), smoking (P=0.004), and lower postoperative ibuprofen dose (P=0.002) were associated with greater opioid dose requirements. CONCLUSIONS: Findings suggest women with chronic back pain and migraine do not report different postpartum pain intensities; however, women with preexisting chronic back pain required 13 MME greater opioid dose than those with migraine during 48 hours after cesarean delivery.

Williams Syndrome Transcription Factor is critical for neural crest cell function in Xenopus laevis.

Williams Syndrome Transcription Factor (WSTF) is one of ∼25 haplodeficient genes in patients with the complex developmental disorder Williams Syndrome (WS). WS results in visual/spatial processing defects, cognitive impairment, unique behavioral phenotypes, characteristic "elfin" facial features, low muscle tone and heart defects. WSTF exists in several chromatin remodeling complexes and has roles in transcription, replication, and repair. Chromatin remodeling is essential during embryogenesis, but WSTF's role in vertebrate development is poorly characterized. To investigate the developmental role of WSTF, we knocked down WSTF in Xenopus laevis embryos using a morpholino that targets WSTF mRNA. BMP4 shows markedly increased and spatially aberrant expression in WSTF-deficient embryos, while SHH, MRF4, PAX2, EPHA4 and SOX2 expression are severely reduced, coupled with defects in a number of developing embryonic structures and organs. WSTF-deficient embryos display defects in anterior neural development. Induction of the neural crest, measured by expression of the neural crest-specific genes SNAIL and SLUG, is unaffected by WSTF depletion. However, at subsequent stages WSTF knockdown results in a severe defect in neural crest migration and/or maintenance. Consistent with a maintenance defect, WSTF knockdowns display a specific pattern of increased apoptosis at the tailbud stage in regions corresponding to the path of cranial neural crest migration. Our work is the first to describe a role for WSTF in proper neural crest function, and suggests that neural crest defects resulting from WSTF haploinsufficiency may be a major contributor to the pathoembryology of WS.