Comparison between ultrasound-guided paravertebral nerve block and subarachnoid block for elderly male patients under unilateral-opened inguinal hernia repair operation: A randomised controlled trial

Background: Paravertebral block (PVB) as a sole anesthetic technique is difficult even in experienced hands. Hence, this study was undertaken to study the safety and efficacy of PVB and to compare with subarachnoid block (SAB) for inguinal hernia repair surgery (IHRS) in elderly male patients. Materials and methods: Sixty-five male patients aged 65 to 89 scheduled for IHRS were allocated randomly by computer-generated randomisation sequence into two groups. They underwent PVB (Group PVB: 33 patients were injected with 10 ml ropivacaine 0.5% at each level from T12 to L1) or SAB (Group SAB: 32 patients were injected with 15 mg ropivacaine 0.5% at L3-L4 level). Primary outcomes were hemodynamic changes and duration of postoperative analgesia. Secondary outcomes were dosage of remedial analgesics, time to perform the block, side effects and satisfaction of patients. Results: The hemodynamics in the Group PVB were more stable than those in the Group SAB during surgery (P < 0.05). The duration of post-operative analgesia was significantly longer in the Group PVB (P < 0.001). The total dose of fentanyl was smaller in the Group PVB in the first 24 h (P < 0.001). The time to perform the block was significantly longer in the Group PVB (P < 0.001). There was a significant difference in the visual analogue scales (VAS) scores between the two groups at 4 h, 6 h, 8 h and 10 h (P < 0.05) but not at 2 h, 12 h and 24 h (P > 0.05). The VAS scores were lowest at 2 h for both the 2 groups, highest at 12 h for Group PVB and at 8 h for Group SAB respectively. The Group PVB had fewer adverse effects (P < 0.05) and higher satisfaction of patients (P < 0.05). Conclusion: Ultrasound-guided PVB can ensure the anesthetic effects of unilateral-opened IHRS in elderly male patients. It has a small impact on hemodynamics, a longer postoperative analgesia time and less complications.