Background
To compare the analgesic effects of thoracic paravertebral block versus lidocaine infusion for management of post-thoracotomy pain.
Methods
60 patients who were scheduled for thoracotomy were randomly divided into two equal groups: IV group received 1.5 mg/kg of 1% lidocaine over 10 min then infusion of 1.5 mg/kg/h, and thoracic paravertebral group (PVB) received 10 ml lidocaine 1% over 30 s then infusion of 1.5 mg/kg/h through catheter was inserted under ultrasound guidance. Hemodynamic and respiratory variables, frequency and duration of postoperative mechanical ventilation, duration of ICU stay, time till start of respiratory exercise and till chest tube removal, analgesia was assessed using 100-point visual analogue scale and defined as VAS <30 mm at rest, and in case of inadequate analgesia, IV morphine 2 mg bolus was given. Frequencies of complications and postoperative hospital stay were also recorded.
Results
17 patients of both groups were maintained on MV for mean duration of 1.5 ± 0.5 days. PVB group was successfully weaned from MV and extubated after significantly shorter duration. Mean duration of ICU stay, time till start of respiratory exercise, and till removal of chest tube were significantly shorter in PVB group. All patients requested analgesia, but the frequency of consumption and mean number of requests were significantly higher in IV group. VAS scores determined at 1, 2, 12, 36 and cumulative 48 hours were significantly lower in PVB group compared to IV group.
Conclusion
Ultrasound guidance allowed safe paravertebral space catheterization. PVB using continuous lidocaine infusion provided adequate analgesia for post-thoracotomy pain with significant reduction of rescue analgesia, shorter time till respiratory exercises start, minimal complications and shorter hospital stay.