A Comparative Study between Chloroprocaine and Chloroprocaine with Fentanyl in Diagnostic Knee Arthroscopies under Spinal Anesthesia

Background: Spinal anesthesia is a reliable and safe technique for Diagnostic knee arthroscopies. Due to its short duration of action, Chloroprocaine has earlier regression of sensory block and shorter duration of analgesia. Opioids along with LA,given intrathecally prolong the duration of analgesia without prolonging motor block and time to void. We compared intrathecal use of 1% Chloroprocaine (35 mg) with 1% Chloroprocaine (35 mg) plus Fentanyl (25mcg) in terms of sensory,motor block, duration of analgesia, time to ambulation, time to void, hemodynamic parameters and side effects. Methodology: 60 patients of age group 18-60 years of either sex, belonging to ASA physical status 1 and 2 undergoing diagnostic knee arthroscopies were randomly divided into two groups, 1% Chloroprocaine with normal saline Group C (n=30) and 1% Chloroprocaine with Fentanyl Group F (n=30). Each group received intrathecally either 35 mg(3.5ml) of 1% Chloroprocaine with 0.5ml normal saline or 35mg (3.5ml) of 1% Chloroprocaine with 0.5ml Fentanyl (25mcg). For statistical analysis, unpaired-t-test and chi-square tests were used. Results: The onset of sensory block was earlier in group F when compared to group C (group C-5min vs. group F-3min). Peak block height was higher in group F (T6) when compared to group C (T8). The onset of motor block, duration of motor block, time to unassisted ambulation, and time to void were similar between the groups (p larger than 0.05). Duration of sensory block (85min vs. 65 min) and time to first rescue analgesia (115min vs. 85 min) was prolonged in group F when compared to group C respectively. Pruritus was significantly high in group F (33%) when compared to group C (0%). Conclusion:The addition of Fentanyl to Chloroprocaine resulted in the early onset of sensory block and prolonged analgesia compared to Chloroprocaine alone. This makes the combination of 1%Chloroprocaine (35 mg) with Fentanyl (25 mcg) a better choice for arthroscopic knee surgeries.