Intrathecal ropivacaine with or without tramadol for lower limb orthopedic surgeries

Preservative free tramadol has been used as an adjuvant to intrathecal bupivacaine. However, the effect of the addition of tramadol on intrathecal isobaric ropivacaine has never been studied.

This prospective, randomized, double-blind study was conducted in 50 adult male American Society of Anesthesiologists grade I or II patients, aged 18-60 years, being operated for unilateral femur fractures. An epidural catheter was inserted in L2-L3 interspace and subarachnoid block was given in L3-L4 space. The patients were randomized to receive 0.5 mL normal saline (group R) or 0.5 mL (25 mg) preservative free tramadol (group RT) with 2.5 mL of 0.75% intrathecal ropivacaine. Hemodynamic parameters, sensory level, motor block, sedation and side-effects were recorded. Statistical analysis was done using Student's t-test, Chi-square test, Fischer's exact test and repeated measures ANOVA.

The time of sensory block onset was 9.2 ± 4.9 min and 8.6 ± 5.3 min (P = 0.714) in group R and group RT, respectively. The motor block onset was also comparable in both the groups (P = 0.112). The duration of sensory block was 147.2 ± 37.4 min in group R and 160.4 ± 40.9 min in group RT (P = 0.252). The median maximum block height achieved in both the groups was T6 and the time to achieve the maximum block was also comparable statistically (P = 0.301).

The addition of intrathecal tramadol 25 mg to the isobaric ropivacaine does not alter the block characteristics produced by intrathecal ropivacaine alone.