Epidural volume extension with saline in combined spinal epidural anesthesia for dynamic hip screw surgeries using low dose of intrathecal hyperbaric bupivacaine

Background Combined spinal epidural (CSE) anesthesia is the preferred and widely used method for lower limb orthopedic surgeries. The epidural volume extension ( EVE) technique is a modification of CSE in which the level of sensory analgesia obtained by subarachnoid block is increased by a small volume of saline administered through the epidural catheter. Patients and methods Fifty patients of both sexes, aged between 50 and 70 years scheduled for dynamic hip screw surgery were enrolled in the study. Patients were divided into two groups: group I (the CSEEVE group) included 25 patients who were anesthetized using CSE with EVE and group II (the CSE group) included patients who were anesthetized using CSE without EVE, using the same technique and the same dose of intrathecal hyperbaric bupivacaine and fentanyl. Results Regarding all demographic data (age, height, weight, sex, and duration of operation), there were no statistically significant differences between the studied groups (P = 0.248, 0.901, 0.064, 0.564, and 0.967, respectively). Regarding the block profile, there was a statistically significant difference between the two groups regarding the level of maximal sensory block (P 0.02), as five patients (20%) of group I showed sensory block level extended to T1–T2 and 20 patients (80%) showed sensory block below T2, whereas in group II, the sensory block level in all patients was limited below T2. The time required for reaching the maximal sensory block level was faster in group I, ranging from 8 to 15 min (mean ± SD: 10.7 ± 1.7), whereas in group II the time ranged from 9 to 16 min (mean ± SD: 13.4 ± 2.4; P 0.001). Two-segment regression was faster in group II, ranging from 60 to 80 min (mean ± SD: 67.9 ± 5.1), whereas in group I it ranged from 70 to 95 min (mean ± SD: 81.0 ± 7.3; P 0.001). The time required to reach the maximum motor block was faster in group I, ranging from 3 to 5 min (mean ± SD: 3.8 ± 0.5), whereas in group II the time ranged from 4.5 to 7.5 min (mean ± SD: 6.1 ± 0.8; P 0.001). A volume of 10 ml bupivacaine 0.5% was injected by epidural catheter in 16 patients (64%) in group II, whereas only four patients (16%) in group I required activation of epidural anesthesia (P 0.001). The systolic blood pressure and heart rate showed no significant changes between the two groups. Conclusion It can be concluded that low dose of intrathecal hyperbaric bupivacaine with EVE (10 ml saline) is associated with early onset of motor and sensory block, high level of sensory block, and shorter time of two-segment regression while maintaining hemodynamic stability.