Background: Dexmedetomidine, a highly selective
agonist has been studied in the past for its use as adjuvant to local anesthetics
for spinal anesthesia. Fentanyl has also been used as a spinally administered
adjuvant to various local anesthetics. The aim of this study was to investigate
the duration of motor and sensory block along with the hemodynamic
parameters, neonatal Apgar scores, postoperative analgesia and maternal
satisfaction of overall anesthetic/analgesic regimen in parturients under
ropivacaine 0.75% plus dexmedetomidine or fentanyl spinal anesthesia.
Methods: Forty patients American Society Of Anesthesiology (ASA) I or
II, scheduled for elective cesarean section were studied. Patients were randomly
allocated to receive ropivacaine 0.75% 1.6–2 mL plus 10 g fentanyl
(Group F, n = 20) or ropivacaine 0.75% 1.6–2 mL plus 10 g
dexmedetomidine (Group D, n = 20), intrathecally. The primary outcome was
duration of motor and sensory block. Secondary outcomes were:neonatal Apgar
scores in the first and fifth minute, additional postoperative analgesia, time to
first postoperative analgesic dose and maternal satisfaction of overall
anesthesia and analgesia. Results: Patients in dexmedetomidine group
(Group D) had prolonged duration of motor and sensory block when compared to
patients in fentanyl group (Group F). Mean duration of motor block was
significantly higher in Group D than in Group F (163.75 min versus 124.75 min
respectively, p = 0.013). Regression of the sensory block to T was
significantly prolonged for Group D (158.50 min Group D versus 114.25 min in Group
F, p = 0.021). Neonatal Apgar scores, additional postoperative
analgesia, time to first postoperative analgesic dose and maternal satisfaction
of overall anesthesia/analgesia process, did not statistically differ between the
groups. Conclusions: Intrathecal dexmedetomidine is associated with
prolonged motor and sensory block. Its profile is similar to fentanyl in terms of
cardiovascular stability, sedation, Apgar scores, patient satisfaction and
postoperative analgesia.