Intrathecal hyperbaric or isobaric bupivacaine and ropivacaine with fentanyl for elective caesarean section.

Objective: We aimed to investigate the efficacy of either plain or hyperbaric solutions of intrathecal bupivacaine and ropivacaine on maternal block characteristics, complications, side effects and neonatal parameters to find out which is superior in a single study.

Methods: One hundred and three term parturients were randomly assigned to receive intrathecal 10 mg hyperbaric bupivacaine (Group Bh), 10 mg plain bupivacaine (Group Bp), 15 mg hyperbaric ropivacaine prepared with dextrose 30% (Group Rh) or 15 mg plain ropivacaine (Group Rp) coadministered with fentanyl 20 μg. Sensory and motor block characteristics, analgesia duration, ephedrine consumption, and neonatal and maternal parameters were recorded.

Results: Time to maximum cephalad spread of sensory block was longer in Group Rp than both bupivacaine groups. Time to achieve sensory block at T6 dermatome was similar between both hyperbaric groups (Group Bh:4.5 ± 1.6, Group Rh:4.6 ± 1.1, p>0.05) but Group Rp needed significantly longer time (7.5 ± 5.5 min, p=0.003) than both hyperbaric groups. Duration of motor block was shorter in ropivacaine groups (Group Rh: 90.6 ± 17.3, Group Rp 121.6 ± 33.7) vs. bupivacaine groups (Group Bh: 140.2 ± 33.3, Group Bp: 149.7 ± 46.0); Group Rh being shorter than Group Rp (p<0.05). Ephedrine consumption was less in Groups Rh (20.0 ± 11.9 mg) and Rp (18.3 ± 12.4 mg) vs. Groups Bh (30.0 ± 14.9 mg) and Bp (27.8 ± 15.4 mg) (p=0.006).

Conclusions: Intrathecal hyperbaric ropivacaine 15 mg with fentanyl 20 μg for CSE is suitable since it provides early motor recovery leading to faster patient ambulation, rapid onset of sensory block with less ephedrine.