Investigating the Effects of Adding Fentanyl to Bupivacaine in Spinal Anesthesia of Opium-addicted Patients

Spinal anesthesia in opium-addicted patients can be associated with many complications. Hence, this study aimed to investigate sensory and motor block characteristics, duration of postoperative analgesia, hemodynamic and side effects by adding Fentanyl to bupivacaine in spinal Anesthesia of opium-addicted patients.

In a double-blind randomized clinical trial, 60 American society of Anesthesiology (ASA) class I and II opium-addicted patients under spinal anesthesia in lower abdominal and lower limb operations were randomly classified into two groups of spinal anesthesia with bupivacaine and bupivacaine-fentanyl. Clinical symptoms, side effects, the duration of sensory and motor block, initiation of analgesia requirement and sensory block were assessed.

The study results indicated no significant difference between bupivacaine and bupivacaine-fentanyl groups in regard with demographic, side effects, blood pressure and heart rate, though a significant difference was observed in respiratory rate 5min, 10min, 45min, 75min and 90 min after block. Duration of sensory (100.33 to 138.83) and motor block (93.43 to 107.66) and, initiation of analgesia requirement (165.33 to 187.76) was significantly longer in bupivacaine-fentanyl, though initiation of sensory block (8.83 to 4.93) was significantly longer in bupivacaine.

Addition of fentanyl to bupivacaine in spinal anesthesia increases the duration of sensory and motor block and initiation of analgesia requirement in opium-addicted patients and also decreases initiation of sensory block in these patients.