Maternal factors implicated in fetal bradycardia after combined spinal epidural for labour pain.
OBJECTIVE
Combined spinal epidural analgesia is effective for fast relief of severe labour pain but has been associated with worrisome decreases in fetal heart rate. Since the reasons for this phenomenon remain elusive, some anaesthesiologists may abstain from using this technique. We postulated that factors unrelated to the neuraxial technique could play a role in the decrease in fetal heart rate. To our knowledge, no prospective study has previously looked into this possibility.


METHODS
We collected prospective data on 223 consecutive patients who received combined spinal epidural analgesia (123) or epidural analgesia (100). Maternal blood pressure, analogue pain scores, exogenous infusion of oxytocin, cervical dilatation, maternal age, parity and ethnicity were collected and correlated with the occurrence of decreases in fetal heart rate post combined spinal epidural.


RESULTS
Univariate analysis showed a correlation between the incidence of fetal bradycardia and higher maternal pain scores, older maternal age, and combined spinal epidural analgesia. Multivariate analysis revealed that only pain scores and maternal age were independent predictors of fetal bradycardia post neuraxial blockade.


CONCLUSIONS
Maternal pain scores and older maternal age are factors unrelated to the neuraxial technique that are independent predictors of fetal bradycardia after neuraxial analgesia for labour.
Nicolet
J
J
McGill University Health Centre, Royal Victoria Hospital, Department of Anesthesiology, Montreal, Quebec, Canada.
Miller
A
A
Kaufman
I
I
Guertin
M C
MC
Deschamps
A
A
D000328:Adult; D000367:Age Factors; D015360:Analgesia, Epidural / Q000009:adverse effects*; D000773:Anesthesia, Obstetrical / Q000009:adverse effects*; D000775:Anesthesia, Spinal / Q000009:adverse effects*; D001794:Blood Pressure / Q000187:drug effects; D001919:Bradycardia / Q000209:etiology*; D005260:Female; D006340:Heart Rate, Fetal / Q000187:drug effects; D006801:Humans; D048949:Labor Pain / Q000188:drug therapy / Q000503:physiopathology*; D009035:Mothers; D010147:Pain Measurement; D011247:Pregnancy; D011446:Prospective Studies; D016896:Treatment Outcome