///2010 Abstract Details
2010 Abstract Details2018-05-01T17:52:49+00:00

Prediction of acute post-cesarean pain: preliminary data from a multicenter project on the prediction of post-operative pain (PPOP)

Abstract Number: 69
Abstract Type: Original Research

Ruth Landau MD1 ; Monica MSC Cardoso MD, PhD2; Patricia Lavandhomme MD, PhD3; Michal Granot PhD4; Philippe Richeb MD, PhD5; John C Kraft BSc6

Background

Acute severe post-CS pain occurs more often than was thought⑴ and 10% of women develop persistent pain⑵. Individual variability in severity of pain after CS is influenced by genetics, ethnicity, sensitivity to pain, and psychological variables. A recent approach to study pain perception focuses on mechanisms that influence pain modulation via Diffuse Noxious Inhibitory Control (DNIC) and temporal summation (mTs)⑶. mTs has been shown to predict wound hyperalgesia⑷. We hypothesized that pre-CS DNIC, mTs, psychosocial questionnaires along with genetic testing will predict the subset of women at risk for severe acute pain and wound hyperalgesia.

Methods

In an ongoing multicenter study, 800 elective CS under a standardized spinal anesthetic (fentanyl 25μg+morphine 100μg) and multimodal post-op analgesia will be studied. Pre-op tests include: DNIC (contact heat pain with a TSA Pathway and a hot water bath for conditioning stimulus), mTs and psychosocial questionnaires (Spielbergers STAI and Pain Catastrophizing Scale). Post-op pain scores and analgesic requirement are recorded, along with 48h wound mapping with von Frey filament. Persistent pain at 2, 6 and 12m are recorded with self-report questionnaires (e.g. Short-form McGill Pain Questionnaire). DNA is collected and stored for genetic analysis. Hierarchical linear regressions will be used to predict pain severity. Stratification according to recruiting site will be performed to account for ethnic/genetic differences.

Results

183 women are enrolled. Preliminary analysis shows that some degree of wound hyperalgesia is present in 56% of women. Post-op pain scores are correlated with extent of hyperalgesia (r=0.478, p<0.001). DNIC score and mTs are associated with presence or absence of hyperalgesia (Figure).

Discussion

Our preliminary data show that the extent of wound hyperalgesia is correlated with the severity of post-op pain. In addition, pre-op mTs was associated with hyperalgesia. DNIC score was only modestly associated with acute post-op pain and hyperalgesia, which is consistent with a study in thoracic patients⑶. If mTs can predict individual susceptibility to develop severe post-op pain and wound hyperalgesia, women may be stratified to different risk groups. Targeted multi-modal analgesia in women at risk may then reduce their likelihood to develop chronic pain.

References

1. Pain 2008;140:87-94

2. Anaesth Inten Care 2009;5:748-52

3. Current Opin Anesth 2009;3:425-30

4. SOAP 2009:A-258



SOAP 2010