Comparison of Duration of Spinal Anesthesia with Lidocaine or Lidocaine plus Epinephrine between Addicts and Non-addicts

BACKGROUND Duration of spinal anesthesia depends on the type of anesthetic agent, dosage and additive materials such as epinephrine, ephedrine and opioid. We compared the duration of spinal anesthesia with lidocaine 5% with or without epinephrine in addict and non-addict patients undergoing inferior limb fracture surgery. METHODS This single blinded randomized clinical trial was performed on 201 males (height ranged 150-180 cm) who referred to the Shahid Bahonar Hospital of Kerman for the inferior limb fracture. Their physical class was matched to the American association standard class 1 and 2, and they were appropriate candidates for the spinal anesthesia. The addict or non-addict groups were each divided into two subgroups. 75 mg of 5% lidocaine was prescribed for one subgroup, and the other subgroup received 75 mg of 5% lidocaine plus 0.2 mg epinephrine. The level of primary anesthesia was elevated to T6. Duration of returning to the 4 primary sensory levels was measured since baseline. FINDINGS A significant increase in the duration of anesthesia level in both addict and non-addict patients receiving lidocaine plus epinephrine was observed compared to the subgroups receiving lidocaine alone (P < 0.01). Duration of decrease in sensory level in addict subgroups receiving lidocaine or lidocaine plus epinephrine was lower compared to non-addict patients (P < 0.001). In addict subgroup receiving lidocaine alone, a significant decrease was observed in the time needed for decrease in sensory level (P < 0.01). CONCLUSION According to the results of this study, regardless of the anesthetic agent being used, duration of spinal anesthesia was shorter in addict patients compared to non-addict ones. Addition of epinephrine to lidocaine 5% increased the duration of spinal anesthesia in both addict and non-addict patients.