The use of neuraxial adjuvant drugs (neostigmine, clonidine) in obstetrics.
OBJECTIVE
Neuraxial adjuvant drugs are used to improve analgesia and to decrease complications associated with a high dose of a single drug. Opioids are used in routinely, but alpha2-agonists, such as clonidine or cholinesterase inhibitors (neostigmine), have also been used for labour analgesia or to relieve pain following caesarean section. Both drugs possess a common mechanism of action that can be beneficial.


RESULTS
Small doses of intrathecal clonidine (30 microg), combined with local anaesthetics and opioids, prolong labour analgesia. Hypotension can occur and must be promptly treated by ephedrine to avoid fetal side effects. Epidural clonidine (60 to 75 microg) produces prolonged analgesia from local anaesthetics and opioids and allows a ropivacaine sparing effect. Intrathecal neostigmine has analgesic properties, but its gastro-intestinal side effects contraindicate its clinical use. Epidural neostigmine, combined with sufentanil or clonidine, initiates labour analgesia (minimum 6 to 7 microg/kg; 500 microg) without side effects, however, and allows a 'mobile epidural'. Epidural and spinal clonidine can be used to improve postcaesarean section analgesia. Epidural neostigmine at the doses studied produces modest analgesia following caesarean section.


CONCLUSIONS
Co-administration of neuraxial drugs may enhance analgesia and reduce the side effects of each drug. Clonidine and neostigmine may be used in obstetrics, under some conditions.
Roelants
Fabienne
F
Department of Anaesthesiology, Cliniques Universitaires Saint-Luc, Brussels, Belgium. fabienne.roelants@anes.ucl.ac.be
D016362:Analgesia, Obstetrical / Q000379:methods*; D000700:Analgesics / Q000009:adverse effects / Q000627:therapeutic use*; D002585:Cesarean Section / Q000009:adverse effects; D002800:Cholinesterase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D003000:Clonidine / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007743:Labor, Obstetric / Q000187:drug effects; D009388:Neostigmine / Q000009:adverse effects / Q000627:therapeutic use*; D010146:Pain / Q000517:prevention & control*; D010149:Postoperative Pain / Q000517:prevention & control; D011247:Pregnancy
D000700:Analgesics; D002800:Cholinesterase Inhibitors; D009388:Neostigmine; D003000:Clonidine