title: Effects of epidural injection on spinal block during combined spinal and epidural anesthesia for cesarean delivery.
abstract: OBJECTIVE
  Epidural injection has been known to enhance spinal anesthesia in combined spinal and epidural (CSE) anesthesia. Saline and local anesthetics have been reported to have a volume effect, elevating sensory level when supplementing a volume into the epidural space. We evaluated the effects of epidural injection when using the CSE technique for cesarean delivery.
  
  
  METHODS
  Sixty-six parturients were allocated randomly into group C (control, n = 21), S (saline, n = 21), or B (bupivacaine, n = 24): epidural injections of 10 mL saline and 0.25% bupivacaine were given in groups S and B, respectively, 10 minutes after they received 8 mg of 0.5% hyperbaric bupivacaine intrathecally, and no injection was given in group C. The sensory level at 10 minutes, the maximal level and the time to reach it, and degree of motor block and muscle relaxation were compared. We also investigated intraoperative side effects and postoperative findings in the postanesthesia care unit.
  
  
  RESULTS
  Epidural injection raised the sensory level significantly in groups S and B, but the maximal height of sensory block and degree of muscle relaxation did not differ among the groups. Fewer patients complained of intraoperative pain in group B than in the other groups (P <.001).
  
  
  CONCLUSIONS
  We could not achieve satisfactory surgical analgesia with 8 mg of hyperbaric bupivacaine injected into the subarachnoid space using the needle-through-needle technique in cesarean deliveries. An epidural saline injection elevated the sensory level, which did not improve the spinal block, whereas an epidural injection of 10 mL of 0.25% bupivacaine enhanced the spinal block and sustained the block postoperatively.
authors.affiliation: Department of Anesthesiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-Dong, Kangnam-Ku, 135-710 Seoul, Korea. dhchoi@smc.samsung.co.kr
authors.forename: D H
authors.initials: DH
authors.lastname: Choi
authors.forename: N K
authors.initials: NK
authors.lastname: Park
authors.forename: H S
authors.initials: HS
authors.lastname: Cho
authors.forename: T S
authors.initials: TS
authors.lastname: Hahm
authors.forename: I S
authors.initials: IS
authors.lastname: Chung
mesh_terms: D000328:Adult; D000767:Anesthesia, Epidural; D000773:Anesthesia, Obstetrical; D000775:Anesthesia, Spinal; D000779:Anesthetics, Local / Q000008:administration & dosage*; D002045:Bupivacaine / Q000008:administration & dosage* / Q000009:adverse effects; D002585:Cesarean Section; D005260:Female; D006801:Humans; D007267:Injections; D011247:Pregnancy
chemical_list: D000779:Anesthetics, Local; D002045:Bupivacaine