Epinephrine reduces the sedative side effects of epidural sufentanil for labour analgesia.
OBJECTIVE
The use of opioids in labour analgesia has primarily been as an adjuvant to local anesthetics. For early labour, satisfactory analgesia with epidural sufentanil alone is possible. This study evaluates the impact of epinephrine on sedative side effects and analgesia related to the latter technique.


METHODS
After Institutional Review Board approval and informed consent this prospective, randomized, double-blind study evaluated 43 nulliparous subjects requesting epidural analgesia. The study site, a tertiary care obstetric unit, accommodates 3500-4500 deliveries annually. Group selection was randomized and blinded by selection of a sealed envelope containing a number which corresponded to a premixed labelled syringe of saline or epinephrine (100 microg/mL). An epidural catheter was placed in a standardized fashion. All subjects received 40 microg of sufentanil and 0.5 mL from the premixed syringe, diluted to 10 mL with NaCl. A blinded observer collected data on maternal sedation, lightheadedness, hemodynamics, oxygenation, and fetal heart rate over a one-hour period following sufentanil injection.


RESULTS
The addition of epinephrine significantly (P <0.05) reduced the incidence of sedation and lightheadedness after epidural sufentanil at all data collection points, except two. Analgesic duration was also significantly prolonged by this addition (120 +/- 56 vs 84 +/- 32 min). Maternal satisfaction was high regardless of solution.


CONCLUSIONS
Forty micrograms of epidural sufentanil produces satisfactory analgesia in early labour. The addition of epinephrine improves the side effect profile of this technique while prolonging the duration of analgesia. Epidural sufentanil requires attention to maternal monitoring of oxygenation as maternal desaturation occurred in both groups.
Armstrong
Kevin P
KP
Department of Anesthesiology, St. Joseph's Health Care London, London, Ontario, Canada. Kevin.armstrong2@sympatico.ca
Kennedy
Brent
B
Watson
James T
JT
Morley-Forster
Patricia K
PK
Yee
Irvan
I
Butler
Ronald
R
D000322:Adrenergic Agonists / Q000627:therapeutic use*; D000328:Adult; D015360:Analgesia, Epidural / Q000009:adverse effects*; D016362:Analgesia, Obstetrical / Q000009:adverse effects*; D000701:Analgesics, Opioid / Q000009:adverse effects* / Q000493:pharmacokinetics; D016292:Procedural Sedation / Q000009:adverse effects*; D004311:Double-Blind Method; D004837:Epinephrine / Q000627:therapeutic use*; D005260:Female; D005323:Fetal Monitoring; D006340:Heart Rate, Fetal / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D010101:Oxygen Consumption / Q000187:drug effects; D010147:Pain Measurement / Q000187:drug effects; D017060:Patient Satisfaction; D011247:Pregnancy; D017409:Sufentanil / Q000009:adverse effects* / Q000493:pharmacokinetics; D011795:Surveys and Questionnaires
D000322:Adrenergic Agonists; D000701:Analgesics, Opioid; D017409:Sufentanil; D004837:Epinephrine