Comparing Effects of Intrathecal Adjuvants Fentanyl and Dexmedetomidine with Hyperbaric Ropivacaine in Patients Undergoing Elective Infraumbilical Surgeries: A Prospective, Double-Blind, Clinical Study.

Background: Spinal anesthesia is most commonly used anesthesia technique for infraumbilical surgeries, and it is cost-effective with decreased hospital stay. Intrathecal isobaric ropivacaine has shorter duration of anesthesia than bupivacaine. By making, ropivacaine hyperbaric will help to achieve dense block with good postoperative analgesia.

Materials and Methods: Ninety patients with American Society of Anesthesiologists physical status Classes I and II, aged between 18 and 60 years of either sex, undergoing for elective infraumbilical surgeries were randomly allocated into three groups 30 each ( n = 30). Group Ropivacaine + Dexmedetomidine (RD) received 2.5 ml of 0.5% hyperbaric ropivacaine (15 mg) + dexmedetomidine 10 μg (0.5 ml), Group Ropivacaine + Fentanyl (RF) received 2.5 ml of 0.5% hyperbaric ropivacaine (15 mg) + fentanyl 25 μg (0.5 ml), and Group Ropivacaine + Normal saline (RC) received 2.5 ml of 0.5% hyperbaric ropivacaine (15 mg) +0.5 ml of normal saline. The onset, extent, and duration of sensory and motor block, duration of rescue analgesia, hemodynamic parameters, and side effects such as nausea, vomiting, pruritus, and shivering were recorded.

Results: Time of onset early in RD (1.673 ± 0.567), in RF (1.73 ± 0.520), and in RC (1.763 ± 0.420) min ( P = 0.783). Time to achieve maximum level of sensory block in RD (5.94 ± 1.88), in RF (3.86 ± 1.22), and RC (5.99 ± 0.46) min ( P < 0.001). The total duration of analgesia in Group RD (356.67 ± 63.022), in RF (255.10 ± 35.626), and in RC (197.67 ± 37.605) min ( P < 0.001). The time onset and duration of motor block in Group RD (1.59 ± 0.59, 319.57 ± 64.752), Group RF (1.59 ± 0.53, 236.83 ± 33.797), and Group RC (2.07 ± 0.20, 183.93 ± 35.252) min both are statistically highly significant ( P < 0.001).

Conclusion: Addition of glucose to ropivacaine makes the block dense. Addition of adjuvants such as dexmedetomidine and fentanyl further hastens the onset; prolong the postoperative analgesia with minimal hemodynamic and other side effects.