Clinical observation of regular intermittent epidural injection combined with different puncture points in suppressing breakthrough pain in labour analgesia.

The aim of the current study was to evaluate the clinical effects of the regular intermittent epidural injection combined with different puncture points (RIEI-dPP) in suppressing breakthrough pain during a labour analgesia. A total of 90 primipara were randomly divided into three groups (n = 30): Group L2-3 (A), Group L3-4 (B) and Group L4-5 (C). The analgesic pump parameters were set as: impact dose 8 mL, locking time 15 minutes, background dose 0, and the additional impact dose 8 mL after each hour intermittence. The pain's visual analogue scale (VAS), breakthrough pain, maximum block segment, modified Bromage score, labour duration and the neonatal Apgar score were recorded and compared. Compared with the pre-analgesia time, the VAS scores were found to be significantly decreased in the three groups (p < .05), but there were significant differences among the three groups (p > .05). During analgesia, the maximum block segment in Group C was more significantly reduced than in the other two groups (p > .05), but there was no significant difference in the breakthrough pain among the three groups (p > .05). The comparison of other indexes among the three groups showed there was no significant difference (p > .05). RIEI-dPP at L2-3, L3-4 and L4-5 during labour analgesia can effectively inhibit breakthrough pain. Impact Statement What is already known on this subject? According to human anatomical features, the injection speed and capacity are the prerequisite for obtaining the ideal block range. Experiments confirm that a more uniform and wider drug distribution can be achieved by epidural intermittent rapid infusion with higher injection pressure than a continuous infusion with low injection pressure. Compared with the continuous epidural administration mode, the regular intermittent epidural injection mode can better inhibit breakthrough pain with a lower amount of anaesthetic. What the results of this study add? Similar labour analgesic effects can be achieved by regular intermittent epidural injection mode with different puncture points. What the implications are of these findings for clinical practice and/or further research? Compared with a continuous infusion, a regular intermittent epidural injection can achieve a more uniform drug distribution in the epidural space, so the block range can be more extensive, which can not only reduce the amount of anaesthetic but also effectively reduce the incidence of breakthrough pain. However, the selection of an intervertebral puncture site still lacks a uniform standard. The outcomes of this study can directly verify that regular intermittent epidural injection at L2-3, L3-4 and L4-5 can effectively inhibit breakthrough pain and achieve good analgesic effects, so selecting the intervertebral space with clear anatomical structure positioning and easier puncture pathway can benefit a labour analgesia.